Khabat Thermal Power Plant Units 1&2 and Bazyan 400kV Substation
EPC/TURNKEY BIDDING PACKAGE Bidding No. :
PART 3 Volume I Technical Specification for Power Plant
CONTENTS LIST OF ABBREVIATIONS VOLUME I 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.
TECHNICAL SPECIFICATION
PROJECT DESCRIPTION PLANT DESIGN CRITERIA SCOPE OF WORK GENERAL REQUIREMENTS SITE DETAILS AND SAFETY REQUIREMENTS MECHANICAL PLANT AND SYSTEMS ELECTRICAL CONTROL, INSTRUMENTATION AND COMMUNICATIONS CIVIL WORKS QUALITY CONTROL, INSPECTION AND TESTING COMMISSIONING, START-UP AND TESTING
VOLUME II
SCHEDULES
A. B. C1. C2. C3. C4. D.
Site Particulars Dates of Despatch, Delivery to Site and Completion Manufacturers Guarantee Particulars Mechanical Schedules Electrical Schedules Control and Instrumentation Schedules Suppliers of Materials, Manufacturers, Places of Manufacture Testing and Inspection E. Drawings and Documentation F. Variations from Specification G1. General Tests and Inspections G2. Tests in Manufacturer’s Works G3. Site Tests H. List of Spare Parts and Consumables J. List of Special Tools and Equipment VOLUME III APPENDICES 1. PLOT PLAN 2. GENERAL ARRANGEMENT 3. SYSBOL & LEGEND 4. FLOW DIAGRAM 5. SINGLE LINE DIAGRAM 6. CONTROL SYSTEM CONFIGURATION DRAWING 7. BASIC PLANT OPERATION SCHEME ON PCS
(i)
LIST OF ABBREVIATIONS %
per cent
°C
degrees Celsius
A
ampere
ac
alternating current
AFFF
aqueous film forming foam
AGI
above ground installation
AGMA
American Gear Manufacturers Association
ANSI
American National Standards Institute
API
American Petroleum Institute
ASME
American Society of Mechanical Engineers
ASTM
American Society for Testing of Materials
AVR
automatic voltage regulator
AWS
American Welding Society
AWWA
American Water Works Association
barg
bar gauge
BCSA
British Construction Steelwork Association
BMS
Building Management System
BoP
balance of plant
BS
British Standards
C&I
control and instrumentation
C/H
(C/H ratio)
CCCW
closed circuit cooling water
CCGT
combined cycle gas turbine
CCR
central control room
CCTV
closed circuit television
CCW
closed cooling water
CD
compact disc
CD Rom
compact disc read-only memory
CEMS
continuous emissions monitoring system
CFD
Computational Fluid Dynamics
CO
carbon monoxide
CPU
central processor unit
Cr
chromium
CT
current transformer
( ii )
CV
flow coefficient
CV
curriculum vitae
CW
circulating water
dB
decibel
dB(A)
decibel (A weighted)
dc
direct current
DEH
digital electro-hydraulic
demin
demineralization
DFR
design flow rate
DGP
data gathering panels
DLT
digital linear type
EHV
extra high voltage
EMC
electromagnetic compatibility
EN
Euro Norme
EPA
Environment Public Authority
EPC
engineer, procure, construct
EPR
ethylene propylene rubber
EWS
engineer’s workstation
FAT
Factory Acceptance Test
FCAW
flux-cored arc welding
FD
Fire Department
FGD
flue gas desulphurization
FM GMAW
gas metal arc welding
GMT
Greenwich mean time
GPS
global positioning system
GRP
glass reinforced plastic
GSC
gland steam condenser
GT
gas turbine
GTAW
gas tungsten arc welding
H&S
health and safety
HAZID
hazard identification
HAZOP
hazard and operability
HCFC
single hydrochlorofluorocarbon compound
HEI
Heat Exchange Institute
HMI
human machine interface
( iii )
HP
high pressure
HRSG
heat recovery steam generator
HV
high voltage
HVAC
heating ventilation and air-conditioning
Hz
hertz
I/O
input/output
I/P
input
IBC
intermediate bulk containers
IBM
International Business Machines
IEC
International Electrotechnical Commission
IEEE
Institute of Electrical and Electronics Engineers
IP
intermediate pressure
IP
International Protection
IPB
isolated phase busbar
ISDN
integrated service digital network
ISO
International Standards Organisation
kg
kilogram
KKS
Kraftwerk Kennzeichen System
km
kilometre
kN
kiloNewtons
kV
kilovolt
kW
kilowatt
LAeq
equivalent steady sound level in dB (a) containing the same acoustic energy as the actual fluctuating sound level over a given period
LAN
local area network
lb
pound
LCV
lower calorific value
LP
low pressure
LSF
low smoke and fume
lub
lubrication
LV
low voltage
m
metre
m
metre
m/s
metres per second
m2
metres squared
( iv )
m3
metres cubed
mA
milliampere
mb
millibar
MCB
miniature circuit breaker
MCC
motor control centre
MCC
motor control centre
MCR
maximum continuous rating
MED
multiple effect distillation
mg
milligram
mg/l
milligram per litre
MI
mineral insulated
MIG
metal inert gas
mm
millimetre
mm2
millimetre squared
MMA
manual metal arc
MOV
Motor Operated Valve
MPI
Magnetic Particle Inspection
MSS
Manufacturers Standard Society
MTBF
mean time between failure
MTTR
mean time to repair
MV
medium voltage
MVA
megavolt ampere
MVAr
megavolt-ampere reactive
MVArh
megavolt-ampere hours
MW
megawatt
MWe
megawatts electrical
MWh
megawatt-hour
NB
nominal bore
NDE
non-destructive examination
NDT
non-destructive testing
NFPA
National Fire Protection Agency
Nm3
normal metres cubed
NOx
oxides of nitrogen
NPHR
net plant heat rate
NPO
net power output
NPSH
net positive suction head
(v)
O&M
operation and maintenance
O/P
output
O2
oxygen
OCGT
open cycle gas turbine
ONAF
oil natural air forced
ONAN
oil natural air natural
P&ID
piping and instrumentation diagram
PA
public address
PABX
private automatic branch exchange
PCS
plant control system
PD
Pressure Directive
pH
index of acid concentration
PLC
programmable logic controller
PN
nominal pressure
ppm
parts per million
PSS
power system stabilizer
PSTN
public switched telephone network
PTFE
polytetrafluoroethylene
PTZ
pan-tilt-zoom
PVC
polyvinyl chloride
QC
Quality Control
QCC
Quality Control Certificate
QCR
Quality Control Record
RH
relative humidity
rms
root mean square
rpm
revolutions per minute
RSO
recurrent surge oscillogram
RTD
resistance thermometer detector
SAW
submerged arc welding
SCADA
Supervisory Control and Data Acquisition
SF6
sulphur hexafluoride
SFC
static frequency converter
SMACNA
Sheet Metal and Air Conditioning Contractor National Association
SMAW
shielded metal arc welding
SO2
sulphur dioxide
( vi )
SOE
sequence of events
SPN
single phase neutral
ST
steam turbine
TEMA
Tubular Exchanger Manufacturers Association
TEWAC
totally enclosed water cooled
TIG
tungsten inert gas
TPN
three phase neutral
TV
television
UHF
ultra high frequency
ULSS
stainless steel
UPS
uninterruptible power supply
UV
ultra violet
V
volt
VCR
video cassette recorder
VDE
Verband Der Elektrotechnik Elektronik Informationstechnik e.V
VDU
visual display unit
VOC
volatile organic compounds
VT
voltage transformer
VWO
valve wide open
WB
World Bank
WHO
World Health Organization
WTP
water treatment plant
XLPE
cross linked polyethylene
( vii )
VOLUME I
TECHNICAL SPECIFICATIONI
1. PROJECT DESCRIPTION 1.1 1.2 1.3
General Site Description Target Project Start and Completion
2. PLANT DESIGN CRITERIA 2.1 2.2 2.3
General Unit Rating Site Layout
2.4
Plant Operating Philosophy 2.4.1 2.4.2 2.4.3 2.4.4
2.5 2.6
Seismic Design Performance Criteria 2.6.1 2.6.2
2.7
Condition of Service Site Conditions Fuel/Water Supplies Grid Conditions
Output and Heat rate Plant Start -Up
Environmental criteria 2.7.1 2.7.2 2.7.3 2.7.4 2.7.5
Noise Emissions to Air
Ambient Air Quality Aqueous Emissions Visual Impact
3. SCOPE OF WORK 3.1 3.2
Summary of Main Scope and Services Terminal Points 3.2.1 3.2.2 3.2.3 3.2.4 3.2.5 3.2.6 3.2.7
Fuel Supplies Water Supplies Cooling Water System Electrical Connections Communications Drainage Security Fencing and Access Roads
(i)
4. GENERAL REQUIREMENTS 4.1
Project Management 4.1.1 4.1.2 4.1.3 4.1.4 4.1.5 4.1.6 4.1.7 4.1.8 4.1.9
4.2
Programs and Progress 4.2.1 4.2.2
4.3 4.4
Drawings Enclosed with the Specification Schedules Drawings and documents to be submitted by the Tender Drawings and documents to be submitted by the Bidder Drawings and document format Drawing sheet numbers Drawing and document revision Drawing and document status
Operating and maintenance instructions HAZOP studies Places of manufacture, testing and inspection Packing and marking on packages Training 4.9.1 4.9.2
4.10 4.11 4.12
Program Requirements Progress Reporting
Design and Standardization Drawings and Documents 4.4.1 4.4.2 4.4.3 4.4.4 4.4.5 4.4.6 4.4.7 4.4.8
4.5 4.6 4.7 4.8 4.9
Overall Scope Organization Operation of Computer system for project management Project Management Plan Health, Safety and Environmental Management Plan Environmental Protection Project Quality Plan Training Plan for MOE personnel Project Control Procedures
General Content of training
Spare parts Special tools and lifting devices Warranty engineer
5. SITE DETAILS AND SAFETY REQUIREMENTS 5.1 5.2 5.3
Location of Site, access and use of Site Site facilities Site services during construction period 5.3.1 5.3.2 5.3.3
5.4
Site construction electricity supplies Water supplies Other services
Health and safety at work
( ii )
5.4.1 5.4.2 5.4.3 5.4.4 5.4.5 5.4.6 5.4.7 5.4.8 5.4.9 5.4.10 5.4.11 5.4.12 5.4.13 5.4.14 5.4.15 5.4.16 5.4.17 5.4.18 5.4.19 6.
Risk assessment Specific risks produced by Bidder activities Documents Bidder 's safe systems of working Training Safety equipment Assistance to Owner Confined spaces Land owned by third parties Temporary electricity supply Fire precautions Compressed gases Access, fencing and safety barriers Site rules First aid and medical facilities Emergency evacuation of the Site Safety management Cranes, hoists, lifting equipment and scaffolds, etc Electrical safety conditions
MECHANICAL PLANT AND SYSTEMS 6.1 6.2 6.3 6.4 6.5 6.6 6.7 6.8 6.9 6.10 6.11 6.12 6.13 6.14 6.15 6.16 6.17 6.18 6.19 6.20 6.21 6.22 6.23 6.24 6.25 6.26 6.27 6.28 6.29 6.30 6.31
Boiler and its accessories Fuel Supply and Storage System Electrostatic Precipitator Ash Handling System Turbine Generator and Accessaries Condensate System Feedwater System Main and Reheat System Feedwater Heater, Extraction , Drain and Vent System Auxiliary Steam System Closed Cooling Water System Circulating Water System Compressed Air System Water Supply and Treatment System Chemical Feed and Sampling System Auxiliary Boiler Diesel Generators Service Gas System Fire Protection and Detection System Crane and Lifting Equipment Laboratory Equipment Workshop and stores Equipment General Plant Requirements Painting and Protection against Corrosion Packing and marking on packages Flue gas Desulfurization system Waste water treatment system Sewage water treatment system Sump pump Piping Elevators
( iii )
7.
ELECTRICAL 7.1
General 7.1.1 7.1.2 7.1.3 7.1.4 7.1.5 7.1.6 7.1.7 7.1.8
7.2
Generators 7.2.1 7.2.2 7.2.3 7.2.4 7.2.5 7.2.6 7.2.7 7.2.8
7.3
Function Major components Design criteria
Transformers 7.6.1 7.6.2 7.6.3
7.7
Function Major components Design criteria
Generator circuit breaker 7.5.1 7.5.2 7.5.3
7.6
Rectifier Excitation transformer Control equipment Field suppression Connections Monitoring and protection
Generator main connections and neutral earthing 7.4.1 7.4.2 7.4.3
7.5
General Rating and capability Generator cooling Gas systems Demineralized water system Terminals Sliprings and brushgear Instrumentation and metering
Excitation system and equipment 7.3.1 7.3.2 7.3.3 7.3.4 7.3.5 7.3.6
7.4
Nominal voltage ratings Electrical equipment enclosure Control and selector switches Switchboards, panels and cubicles Indicating lamps and fittings Panel wiring and terminal boards Current transformers Voltage transformers
Function Major components Design criteria
Switchgear 7.7.1 7.7.2 7.7.3
Function Major components Design criteria
( iv )
7.8
DC supplies system 7.8.1 7.8.2 7.8.3
7.9
Uninterruptible power supply equipment 7.9.1 7.9.2 7.9.3
7.10
Function Major components Design criteria
Function Major components Design criteria
Electrical control system 7.10.1 General 7.10.2 Design criteria
7.11
Electrical protection 7.11.1 General 7.11.2 Design criteria
7.12
Synchronizing
7.13
Motors 7.13.1 General 7.13.2 Design criteria
7.14
Earthing and Lightning Protection 7.14.1 General 7.14.2 Design criteria
7.15
Cabling 7.15.1 7.15.2 7.15.3 7.15.4 7.15.5 7.15.6 7.15.7 7.15.8 7.15.9 7.15.10 7.15.11
General Medium voltage cables Low voltage cables Control and instrumentation cables Optical fiber cables Telephone cables High temperature cables Thermocouple and compensating cables Intrinsically safe cables Mineral insulated cables Cable installation
7.16
Cathodic Protection System
7.17
Variable speed drives
7.18
Electrical equipment for hazardous areas
(v)
8. CONTROL, INSTRUMENTATION AND COMMUNICATIONS 8.1
Introduction
8.2
Scope of supply
8.3
Objectives
8.4
Operational philosophy
8.5
Control and monitoring of plant 8.5.1 8.5.2 8.5.3 8.5.4
8.6
Steam generator Steam turbine Generator Auxiliary plant
Plant control system 8.6.1 8.6.2 8.6.3 8.6.4 8.6.5 8.6.6
General system design Operator’s facilities Engineer’s workstation System response times Spare capacity Software
8.7
Metering
8.8
Condition monitoring
8.9
Plant performance monitoring
8.10
Emissions monitoring
8.11
Station clock system
8.12
Load dispatch
8.13
Fire detection and alarm system
8.14
Gas detection system
8.15
Private automatic branch exchange (PABX)
8.16
Public address system (PA)
8.17
Closed circuit television, intruder detection and site access control Systems
8.18
Weather station
8.19
General requirements 8.19.1 Introduction 8.19.2 Environmental requirements 8.19.3 Hazardous areas
( vi )
8.19.4 8.19.5 8.19.6 8.19.7 8.19.8 8.19.9 8.19.10 8.19.11 8.19.12 8.19.13 8.19.14 8.19.15 8.19.16 8.19.17 8.19.18 8.19.19 8.19.20 8.19.21 8.19.22 8.19.23 8.19.24 8.19.25
Insulation and isolation Electromagnetic compatibility (EMC) Identification Installation Flow measurements Level measurements Pressure measurements Temperature measurements Position measurements Quality measurements Vibration measurements Control valves and actuators Motorized valves Manual valves Pneumatic actuators/positioners Cubicles and racks Testing Training Documentation Support tools and calibration equipment Spare parts Instrument and electrical test equipment
9. CIVIL WORKS 9.1
General requirements for civil works 9.1.1 9.1.2 9.1.3 9.1.4 9.1.5 9.1.6
9.2
The site specific data 9.2.1
9.3
General The Bidder’s enabling works Scope of main civil engineering and building works
Design of the works 9.4.1 9.4.2 9.4.3 9.4.4
9.5
General
Scope of civil engineering and building works 9.3.1 9.3.2 9.3.3
9.4
General Civil program and method statements Planning and building permits/approvals Site investigations Ground contamination Design and construction
General Preferred structural design concept Materials Civil design parameters
Specific building and architectural requirements 9.5.1 9.5.2
Cladding and decking Metal doors and frames
( vii )
9.5.3 9.5.4 9.5.5 9.5.6 9.5.7 9.5.8 9.5.9 9.5.10 9.5.11 9.5.12 9.6
Materials and workmanship 9.6.1 9.6.2 9.6.3 9.6.4 9.6.5 9.6.6 9.6.7 9.6.8 9.6.9 9.6.10 9.6.11 9.6.12 9.6.13 9.6.14 9.6.15 9.6.16 9.6.17 9.6.18 9.6.19
9.7
Scope of works Lighting systems Small power installation Distribution system Cables and wiring Lightning protection system
Mechanical building services 9.8.1 9.8.2 9.8.3 9.8.4 9.8.5
9.9 9.10 9.11
Codes and Standards Materials Certification of materials Storage of materials Construction plant and equipment Concrete Setting out and monitoring Earthworks Roads, hardstandings, car parks and paths Piling Structural steelwork Surface water drainage and buried pressure pipelines Building drainage Brickwork and blockwork Builder’s work Access Fencing Landscaping Laydown area
Electrical building services 9.7.1 9.7.2 9.7.3 9.7.4 9.7.5 9.7.6
9.8
Internal doors and frames Internal vision panels External walling Internal masonry walling Suspended ceilings Damp proofing Stairs Sanitary ware Finishes Flat roof waterproofing systems (if required)
Scope of works Design information Quality control Domestic hot and cold water services HVAC systems
Sub-bidders Functional requirements Record drawings
( viii )
10. QUALITY CONTROL, INSPECTION AND TESTING
10.1 10.2 10.3 10.4 10.5 10.6 10.7 10.8
General Extent of work Document submission Inspection notification and right of access Inspection and tests Non-conformances Quality control records, certificates and certificates of conformance Specific tests and inspections
11. COMMISSIONING, START-UP AND TESTING 11.1
General 11.1.1 Staffing
11.2
Pre-commissioning 11.2.1 11.2.2 11.2.3 11.2.4 11.2.5 11.2.6 11.2.7 11.2.8 11.2.9 11.2.10 11.2.11 11.2.12 11.2.13
11.3
Commissioning 11.3.1 11.3.2 11.3.3 11.3.4 11.3.5 11.3.6 11.3.7 11.3.8 11.3.9 11.3.10 11.3.11 11.3.12
11.4
Boiler Turbine Generator Condenser Control and instrumentation installation and pre-commissioning Turbine governing equipment Protective relaying Switchboards, cubicles, relay panels, marshalling boxes, enclosures and ancillary electrical equipment Low voltage switchgear Motors Electrical equipment for hazardous areas 1-30 kV XLPE cable and accessories Auxiliary multicore cables
Oil supply systems Boiler Generator Excitation system Generator main and neutral earthing connections Current transformers Voltage transformers Control and instrumentation installation and Commissioning Turbine governing equipment Turbine Pumps Site acceptance tests
Testing 11.4.1 11.4.2 11.4.3 11.4.4
Tests on completion Performance guarantee tests Reliability tests Environmental tests
( ix )
11.4.5 11.4.6 11.4.7 11.4.8 11.4.9 11.4.10
Reporting of test results Performance worse than guaranteed Rejection of plant Liquidated damages Taking over Defects after taking over
(x)
1
PROJECT DESCRIPTION
1.1
General This Specification is intended to assist the Bidder for the design, manufacture, delivery, off-loading at Site, erection, painting, setting to work, testing and attention to defects of the Khabat oil fired power plant units 1&2, to be located in Kurdistan region, which is 30km west of Erbil, Iraq. The station will be constructed on a turnkey basis and shall include all equipment, work and services in order to render the power plant fully complete and functional for safe, reliable and commercial operation under all conditions and respects.
1.2
Site Description The site is in a hilly area in the Khabat District, about 30km west of Erbil, 3.5km north of the village of Khabat, about 1.7km from the Great Zab River. Heavy and large equipment will be unloaded in harbor (if available) and transported through the national highway to site by trailer. Light weight equipment and construction materials can be unloaded on site by truck or trailer. In case that the bridge or underground facility on access way has insufficient strength to bear heavy load, it shall be reinforced for the protection of the existing facilities under Bidder’s responsibility. The Bidder shall be responsible for surveying all routes and obtaining any necessary permits to ensure that all equipment, particularly oversized and heavy loads, can be transported to their required destination.
1.3
Target Project Start and Completion The Works are expected to commence on April 16, 2010, and the plant shall be complete and ready for Operational Acceptance having successfully completed all the tests on completion as defined in Section 11 by December 31, 2012 for Unit 1 and April 30, 2013 for Unit 2.
1-1 KHABAT TPP UNITS 1&2 - VOLUME I
2
PLANT DESIGN CRITERIA
2.1
General This Specification requires a steam generation power plant design that is modern, well proven, safe, and economically attractive both in capital cost and running cost and offering a high availability with low forced outage rate. The plant shall be fully automated and require minimum operator intervention for normal operation. The Bid shall comply with the Specification unless compliance would for any reason put at risk safety, reliability and economy due to deviation from standard practice of the Bid. However, the intent of the Specification shall always be complied with. Any deviations from the Specification shall be clearly identified in Schedule [F], which shall be completed and returned as part of the Bid. The meaning of all terms is as defined in the [EPC Contract Document]. Equipment shall be designed and selected to ensure high reliability and availability of the complete plant with low forced outage rates and minimal maintenance over the lifetime of the power station, which shall be defined as 25 years. An appropriate level of redundancy shall be included in each system; the Works shall be designed so that no single auxiliary plant failure shall result in the total loss of the unit generating capability. In this context, it is required that with agreed exceptions, all unit auxiliaries will be provided with at least one installed spare (N+1). For the station auxiliaries, no single equipment failure shall result in any loss of station generating capability. Prototype plant will not be acceptable, and plant that is offered with limited operating experience must be fully supported by manufacturer’s warranties and indemnities.
2-1 KHABAT TPP UNITS 1&2 - VOLUME I
2.2
Plant performance guarantees The Bidder shall meet the followings plant performance guarantees associated with Khabat Thermal Power Plant.
2.2.1
Plant output and heat rate guarantees Description
Fuel oil Operation
Guaranteed Steam Generation Base load 150,000 < Net plant output [GNPO] (kW) Guaranteed Steam Generation Base Load Net plant heat rate [GNPHR] (kJ/kWh)
38% <
[based on LHV of the fuel] Net plant output is measured at the tariff meter on the HV side of the main transformers The net plant heat rate is defined as: mf [LHV15 + (tf − 15) *cp ] GNPHR = 3600 --------------------------kJ/kWh GNPO where
Description average specific heat capacity of fuel in the temperature range
Cp= 15°C to tf (kJ/kg°C) LHV15=
lower heating value of fuel at 15°C,
mf =
mass flow of fuel (kg/s)
tf =
fuel temperature at delivery point (°C)
2.3
Unit Rating
2.3.1
Maximum guaranteed rating (MGR) Maximum guaranteed rating is a maximum continuous rating guaranteed by the Bidder. The turbine generator shall be designed for an Net Plant Output 2-2 KHABAT TPP UNITS 1&2 - VOLUME I
no less than 150MW measured at the tariff meter, located on the HV side of the step up transformers. The MGR is based on the following condition ; A.
Generator terminal output, kW
[160,000]
2
B.
Main steam pressure, kg/cm gage
169
C.
Main steam temperature, ℃
538
D.
Reheat steam temperature, ℃
538
E.
Number of extraction stage
7
F.
Design Wet Bulb temperature, ℃
25
G. Approach temperature at cooling tower, ℃
[5]
H.
Circulating water temperature rise, ℃
[12]
I.
Exhaust Pressure, mmHgA
[81]
J.
Feedwater makeup, %
0.0
K.
Turbine speed
3,000
L.
Generator rated power factor, lagging
0.85
leading
0.95
M. Generator rated voltage, kV N.
[15]
Short circuit ratio
not less than 0.5
O. Excitation system response ratio * Note : [
2.3.2
not less than 1.0
] value shall be decided by Bidder.
Capability rating (CR) Capability rating is a continuous capable rating at the worst cycle condition. The turbine generator shall be designed for an output not less than that of MGR under the following conditions : A.
Design Wet Bulb temperature, ℃
30
B.
Feedwater makeup, %
3.0
Other conditions such as steam conditions, design wet bulb temp, etc. shall be the same as MGR conditions.
2-3 KHABAT TPP UNITS 1&2 - VOLUME I
2.3.3
Valve wide open (VWO) Valve Wide Open rating is a maximum continuous rating calculated with all steam control valves wide open. At the inlet, boundary conditions specified in paragraph 2.2.1, the turbine generator shall be designed for an output with no less than 105% main steam flow rate at MGR or no less than main steam flow rate at CR, which is bigger.
2.3.4
Boiler maximum continuous rating (BMCR) Boiler Maximum Continuous Rating is a maximum rating specified and guaranteed by Bidder. It shall be designed on the basis of main steam flow at HP turbine stop valve inlet at VWO plus auxiliary steam flow including minimum 20 % margin.
2.3.5
Maximum continuous rating with top heater out-of-service(MCR & THO) MCR & THO is a maximum continuous rating with top heater out-of-service. At the conditions specified in paragraph 2.2.2, the turbine shall be designed for continuous operation, with an output equal to that of Bidder's MGR at the generator terminals and top heater out of service.
2.4
Site Layout The Bidder shall provide a layout generally in accordance with the conceptual site layout provided in Volume 3, conversant with good operating practice, so that maintenance access is fully available to any part of the plant. The layout shall be based on an ‘outdoor’ type boiler installation. The site layout, including plant, buildings, roads, gates, laydown areas, etc. shall take into consideration the requirement for heavy vehicles and cranes required for installation and future maintenance of the plant to access to carry out the necessary work. The site layout shall be subject to approval of the KNOC.
2.5
Plant Operating Philosophy The Plant shall be designed for base load and two shifting operation. The intended operating regime for the immediate future will be base load, operating 8000 to 8150 hours per annum equating to a typical annual availability of 91 to 93 per cent. In addition, the plant shall also be capable of operating on a two-shift operating regime, based on one start per day. Plant normal start-up and shutdown will be initiated from the central control 2-4 KHABAT TPP UNITS 1&2 - VOLUME I
room. All the works shall be operated primarily from the PCS in the central control room. The plant shall be automated to reduce the manual intervention required by operations staff. The boilers shall be capable of start-up, shutdown and continuous operation on the fuels as defined in Schedule A, and each block shall have cold and hot start up capability and be able to operate either individually or in parallel with the other blocks. The plant shall be provided with a black start capability. 2.5.1
Condition of Service
2.5.1.1 Operation capability The Boiler and steam turbine-generator shall be capable of ; A.
Achieving the peak load of valve wide open rating at rated steam temperatures of 538℃/538℃(Turbine) and operate at this overload capacity without any time limitation when as required.
B.
Start up Time Light off~ Steam to turbine
Steam to Turbine ~ MGR
Cold Start Warm Start Hot Start C.
When supplied with steam at the temperature stated in the Contract, the load variations at a rate of minimum 10% of MGR per minute between 50% and 100% MGR, and at a rate of minimum 3% of MGR per minute between 30% and 50% MGR.
D.
Operating at no load. Any time limitation, if applicable, shall be stated by the Bidder.
E.
Accepting 10% MGR load step change within 10 seconds when the unit is operating in the load range of 50% to 100% MGR. After each occurrence of load step change, the turbine shall enter a stabilizing period for the power plant.
2.5.1.2 Normal operation The steam turbine-generator shall be designed to be operated as follows ; A.
Constant pressure operation
2-5 KHABAT TPP UNITS 1&2 - VOLUME I
The main steam pressure remains constant at the rated condition, through all of the operation range, while the load is controlled by either throttling main steam flow with the designed control valve(s). B.
Governor Regulating Operation Between 50% and 100% MGR, the load is regulated by governor within ±5% instantaneous load variation with response to the network frequency fluctuation.
2.5.1.3
Abnormal operation The steam turbine-generator shall be capable of uninterrupted continuous operation under the following conditions ; A. With circulating water shut off from one section of the condenser. B. When the circulating water flow to condenser is reduced to 1/2 normal flow due to pump limitations. C. With full load when one of high pressure feedwater heaters trips out of service. D. With one Air or Hydrogen cooler out of service at 80% rated capacity. E. At approximately full load with system frequencies between [48.5] and [51.5] Hz.
2.5.2
Site conditions Equipment shall be designed and installed to enable safe and flexible operation of the Works over the entire range of operating modes and conditions as defined in this Specification and shall operate safely and reliably over the full range of site ambient conditions listed in this Specification. The Bidder shall be responsible for sourcing all site meteorological data to facilitate the design of the plant, including such air sampling on site as is necessary to ensure the correct design of the boiler air intake filters.
2.5.3
Fuel/water supplies Indicative analyses of the fuel and water supplies to the plant are provided in Schedule A for information. However, the Bidder is responsible for obtaining sufficient data regarding the fuel/water supply conditions, including analyses as
necessary
for
his
design
of
fuel/water
treatment
plant
and
handling/storage facilities, in order to ensure that the required quantity and 2-6 KHABAT TPP UNITS 1&2 - VOLUME I
quality of fuel/water is supplied to the Plant. 2.5.4
Grid conditions The voltage variation on the transmission system will normally remain within the limits stated in Volume 2, Schedule A. The frequency of the transmission system will be nominally 50 Hz, and will normally be controlled within the limits stated in Volume 2, Schedule A. Each generation unit shall have, as a minimum, the following capabilities:
operate continuously maintaining its active power pro rata to transmission system frequencies within the range [48.5] Hz to [51.5] Hz;
remain synchronized to the transmission system at transmission system frequencies within the range [47.5] Hz to [52] Hz for a duration of [60] minutes;
remain synchronized to the transmission system at transmission system frequencies within the range [47] Hz to [47.5] Hz for a duration of [5] seconds required each time the Frequency is below 47.5 Hz;
remain synchronized to the transmission system during rate of change of transmission system frequency of values up to and including [0.5] Hz per second;
sustained operation at the specified minimum stable generation within the range [49.8] Hz to [51] Hz.
For requirements regarding the design of the generators, refer to Section 7.2. 2.6
Seismic Design Iraq is an area of relatively high seismicity and all plant items shall therefore be designed to resist seismic loads. This Project site should be considered to be UBC Zone 3. The United Nations Development Program provides a seismic design code of UBC 97, Zone 3.
2.7
Performance Criteria
2.7.1
Output and heat rate 2-7 KHABAT TPP UNITS 1&2 - VOLUME I
The Bidder shall guarantee the corrected net electrical power output (NPO) and corrected net plant heat rate (NPHR) at the base reference conditions as specified in Volume 2, Schedule [C, Part 1], based on the following definitions: Net electrical power output:
The net plant output is the total plant net
output measured at the tariff meter, located on the HV side of the step up transformers, net of all site auxiliary loads, and transformer losses, corrected to base reference conditions. Net plant heat rate: shall be based on the lower heating value of the fuel and corrected to the base reference conditions The Bidder shall also provide the undernoted curves necessary for correcting power output and specific heat rate from the test conditions to the guarantee base reference conditions in his bid:
2.7.2
A.
Variation in ambient temperature
B.
Variation in barometric pressure
C.
Variation in relative humidity
D.
Variation in fuel LCV and C/H ratio
E.
Variation in grid frequency
F.
Variation in steam temperature and pressure to turbine
Plant start up The Bidder shall guarantee and demonstrate the time for each block to reach full load, and for the steam generator to reach full load from cold, warm and hot starting conditions. Start up curves for the plant shall be provided in the Bid.
2.8
Environmental Criteria The plant shall conform as a minimum with the current World Bank guidelines, the requirements of the local environment authorities in Iraq and with all other relevant consents and regulations.
2-8 KHABAT TPP UNITS 1&2 - VOLUME I
2.8.1
Noise
2.8.1.1 General The facility shall be designed and constructed such that construction workers and operators are exposed to a minimum level of noise. The Bidder shall take appropriate steps to minimize noise exposure through equipment attenuation and procurement of inherently quieter equipment. All noise limits specified in this document are to be evaluated as LAeq levels. This is the energy weighted average of measured noise level as averaged over a specified time period. All sound levels are expressed in terms of decibels as referenced to a sound pressure level of 20 micropascals. The absolute limit of any measured sound pressure level anywhere in the work area shall not exceed 85 dB(A). In locations where it is necessary for operational attendants to make routine examinations closer than 1 m to an accessible part of a running machine which is between 80 and 85 dB(A), the KNOC will wish to adopt hearing protection aids. Therefore the Bidder is required to draw specific attention to portions of the plant where this situation may be encountered and fix appropriate warning labels or signs. Noise within buildings shall comply with the limits specified in Section 9 Civil. 2.8.1.2 Construction noise The maximum noise level caused by construction noise outside the nearest window of the nearest occupied house shall be: Daytime
70 dB(A)
Evening
60 dB(A)
Night
40 dB(A).
Noise levels at all time periods during public holidays shall not exceed 40 dB(A). Noise levels shall be limited to 80 dB(A) or lower at a distance of 1 m from all 2-9 KHABAT TPP UNITS 1&2 - VOLUME I
construction equipment and activities to the fullest extent feasible. If a noise level exceeding 85 dB(A) is likely to occur in any area, warning signs shall be predominantly displayed in that area, indicating that a noise hazard exists and hearing protection must be worn. Any area where noise levels could exceed 90 dB(A) shall have controlled access to prevent unprotected personnel from entering the areas. Peak or intermittent noises such as those resulting from pile driving shall occur during daytime periods only and maximum noise levels shall not exceed 70 dB(A) at the nearest inhabited dwelling. 2.8.1.3 Far field noise during operation The Bidder shall identify the location of the nearest residential, institutional or educational location and establish the background noise level. The noise level including background and contribution from the plant during operation shall either (a) raise background noise level by a maximum of not more than 3 dB(A) at the nearest receptor location off-site or (b) not exceed the following limits, consistent with the new updated version of the EHS Guidelines, replacing the Pollution Prevention and Abatement Handbook 1998: One Hour LAeq (dB(A)) Receptor Residential, institutional,
Daytime
Night time
(07:00 to 22:00)
(22:00 to 07:00)
55
45
70
70
educational Industrial, commercial
A noise test procedure shall be submitted by the Bidder, outlining the proposed method of noise testing, to demonstrate compliance with the stated environmental noise limits. The on-site and environmental noise levels shall be assessed by the Bidder in order to comply with the site requirements relating to noise emissions. The noise level shall not exceed 85dB(A) of overall sound pressure level at a distance of one(1) meter from each equipment. And the maximum noise level at the plant boundary shall be maintained below 65dB(A). Parts of the boilers and the steam turbines shall be enclosed in acoustic enclosures to ensure noise limits are achieved. The Bidder shall ensure that
2-10 KHABAT TPP UNITS 1&2 - VOLUME I
noise emissions are minimized, not only for steam generation plant, but also for the balance of plant equipment. 2.8.2
Emissions to air
2.8.2.1 Emissions during construction The Bidder shall ensure that suitable site practices are employed to ensure that atmospheric dust contamination generated by the construction works do not exceed levels which could constitute a health hazard or nuisance to those persons working on the site or living nearby. 2.8.2.2 Emissions during operation The World Bank has set emission limit for NOx, SO2 and particulate matter from boiler of thermal power plant in July 1998. On April 30, 2007, IFC published new updated versions of the EHS Guidelines, replacing those previously published in the Pollutant Prevention and Abatement Handbook 1998. According to the updated version of the EHS Guidelines for thermal power plants (December 19, 2008), the maximum emission limits for each pollutant of boiler using the liquid fuel are as follows. Parameter
Maximum value 400 mg/Nm3
Nitrogen oxides *
1,500 mg/Nm3
Sulfur dioxide *
50 mg/Nm3
Particulate matter
* The emission limits are referenced to 3% O2, dry flue gas. (Plant > 50MWth to < 600MWth) Continuous monitoring of NOx, SO2, CO, O2 and H2O to correct to dry flue gases shall be made from the main stacks of each boiler and displayed on the PCS. Any exceedances of limit values shall be alarmed. Sampling points and safe access adjacent to the monitoring points shall be included. Any natural gas vent stacks required shall be at a height sufficient to ensure that the concentration of gas at ground level is significantly less than the explosive limit. Emissions of volatile organic compounds from the fuel oil tanks shall be 2-11 KHABAT TPP UNITS 1&2 - VOLUME I
limited by installation of appropriate VOC removal plant, such as active carbon filters. 2.8.3
Ambient air quality The World Bank (WB) has set ambient air quality guidelines for nitrogen dioxide (NO2) and SO2. The guide values from the WB are set out below. World bank air quality guide values (micrograms/cubic meter) Parameter
Reference period
Recommended ground level concentration guide value
Nitrogen dioxide
Sulfur dioxide
Short term exposure (24 hour mean)
150
Long term exposure (annual average)
100
Short term exposure (24 hour mean)
150
Long term exposure (annual average)
80
The plant shall not lead to either the airshed dropping into the category of poor air quality or an increase of more than 5 mg/m3 in the annual mean level of particulates and/or SO2 for the entire airshed. For the purposes of bidding, the minimum height for the main stacks shall be considered as 130 meters, however the Bidder shall be responsible for suitable stack design of sufficient height, temperature and velocity to ensure that the above ambient air quality guidelines are not exceeded in combination with all other contributing sources in the vicinity of the proposed plant. The Bidder shall be responsible for the assessment of the existing background air quality through monitoring data, or where none is available through a modeling exercise. 2.8.4
Aqueous emissions The discharge of any effluents during construction, including site drainage, shall be the responsibility of the Bidder who shall reach agreement with the regulatory authorities and the local sewerage authorities with regard to the detailed methods of disposal. Operational aqueous emissions from the plant shall be treated and 2-12 KHABAT TPP UNITS 1&2 - VOLUME I
discharged in accordance with the following quality limits, consistent with the new updated version of the EHS Guidelines, replacing the Pollution Prevention and Abatement Handbook 1998: Effluent guidelines of waste water Parameter
Maximum, mg/l (except pH and temperature)
pH
6
to 9
COD *
20
TSS
50
Oil and grease
10
Total residual chlorine
0.2
Chromium
0.5
Copper
0.5
Iron
1.0
Zinc
1.0
Lead
0.5
Cadmium
0.1
Mercury
0.005
Arsenic
0.5
Temperature increase at the edge of
3°C
the mixing zone * Not included in the EHS Guidelines Effluent guidelines of sewage water Parameter
Maximum, mg/l (except pH and total coliform bacteria)
pH
6 to 9
BOD
30
COD
125
Total nitrogen
10
Total phosphorus
2
Oil and grease
10
TSS
50
Total coliform bacteria
400 MPN/100ml
2-13 KHABAT TPP UNITS 1&2 - VOLUME I
Aqueous discharges shall be segregated into storm drains, process effluent and domestic sewage streams. Each shall be provided with an appropriate monitoring and treatment system to ensure that the discharge limits are not exceeded. The waste water originating from the power plant shall be treated by waste water treatment facility before discharge to the river. The water treated with physical and chemical method shall be suitable for the conditions of the effluent guidelines. Any areas of the plant that may be subject to oil spillage shall be drained to an oil interceptor and the clean water discharged with the surface water drainage system. A sewage treatment facility shall be installed for the operational phase, sized for the number of operating and maintenance personnel. All fuel oil lubricating storage tanks and chemical storage tanks shall be bunded to contain 110 per cent of the contents of the largest tank. 2.8.5
Visual impact All reasonable measures shall be taken to minimize visual impact of the plant. Structures and buildings shall meet the standards generally accepted for a facility of this type and shall be in accordance with all applicable local and national consents relating to appearance. Final architectural arrangements shall be submitted for approval to the KNOC.
2-14 KHABAT TPP UNITS 1&2 - VOLUME I
3
SCOPE OF WORK
3.1
Summary of Main Scope and Services This Contract provides for the design, manufacture, construction, supply, testing in works, packaging for export, shipping, transport, delivery to Site, unloading at Site, complete erection, health and safety management, painting, commissioning and putting into operation, performance and reliability testing on completion, instruction of the KNOC’s personnel and obligations for the defects liability period of the steam generation power plant. The station shall be constructed on a full design and build, turnkey basis, and it will be the responsibility of the Bidder to ensure that all equipment, scope of work and services are provided in order to render the power plant fully complete and functional for safe, reliable and commercial operation under all conditions and respects. All material, plant and equipment shall be new and fit for the purposes of a steam generation power station. Equipment shall be selected to ensure high reliability and availability of the complete plant with low forced outage rates and minimal maintenance. Permanent, safe access to all items of plant as necessary shall be provided for inspection, operation and maintenance activities. Unless specifically excluded from the scope of work, interconnecting cabling, pipework etc between items of equipment and plant described in this specification shall all be included under this contract, as shall the installation, testing and commissioning of the same. The quantity of equipment shall be based on one (1) unit unless otherwise specified as a common facility. All necessary auxiliary equipment and systems including, but not limited to, the following: Generally, the main supply will include but not be limited to the following (refer to specific sections for further details):
3-1 KHABAT TPP UNITS 1&2 - VOLUME I
3.2
Mechanical Plant and Systems
3.2.1
Boiler and its accessaries A.
Boiler proper and accessories
1) Furnace 2) Drum 3) Superheater 4) Reheater 5) Economizer 6) Structural steels 7) The following boiler proper accessories as required ; a) Attemperators b) Soot blowing system c) Two(2) long retractable furnace thermocouple probe assemblies including cooling system complete with electric operators and position transmitters d) Safety valves and power relief valves including one(1) set hydraulic jack with discharge pipe, common silencer, start-up vent with silencer. e) Refractories and brick. f) Casing. g) Buckstay, lugs and clevises and hanger rods. h) Blowdown tank and/or flash tank, miscellaneous tanks. i) HP bypass system and its attemperator system. j) All drain and vent piping. k) Connections for the required blanking off, hydrostatic testing and chemical cleaning including nozzles, double valves and caps. l) Required
thermocouples
for
monitoring
drum/tube
metal
temperatures brought out to, and including a common junction box covering steam drum, superheater and reheater tubes. m) Required measuring device for monitoring the thermal stress and life expenditure of superheater header, reheater header and other boiler pressure parts. n) Necessary furnace observation ports and/or access ports and/or doors for good direct viewing of all the fires, furnace interior, soot
3-2 KHABAT TPP UNITS 1&2 - VOLUME I
blowing, superheater and reheater, and economizer area and ducting, as well as access as required. o) Remote furnace flame and stack smoke monitoring system including cameras, color monitors and all accessories. p) Drum level monitoring system including electronic level indicators, level and pressure transmitters. B.
Draft system
1) Forced draft fans with inlet silencers and drivers. 2) Combined Induced draft fans and drivers. 3) Gas recirculation fans and drivers, if required. 4) Scanner cooling air fans and drivers. 5) Sealing air fans and drivers. 6) Regenerative air preheaters and drivers. 7) Steam coil air heaters, drain tank with accessories. 8) Required air and gas ducts complete with expansion joints, dampers and
actuators,
all
necessary
auxiliaries
and
associated
instrumentation and controls C.
Fuel burning system
1) Fuel oil burning system with accessories 2) Fuel oil burner atomizing steam system with accessories 3) Light oil burning system with accessories D.
Fuel oil supply system
1) In-line service tank suction heater, heavy oil heaters with accessories. 2) Fuel oil supply system including fuel oil burning pumps and motors, flow meter and integrator, accumulator, all required piping, valves and instrumentation. 3) Fuel oil return pipings including flow meter and integrator, all required valves. 4) Light oil supply system including light oil burning pumps and motors, flow meter and integrator, all required piping, valves, actuators and instrumentation. E.
The following miscellaneous items ;
1) All required thermal insulation and lagging materials. 2) Complete lubricating oil system and cooling water system, as required.
3-3 KHABAT TPP UNITS 1&2 - VOLUME I
3) Set of connections, orifice flanges, and all other items, required for the ASME Performance Test. F. 3.2.2
Instrumentation and controls
Fuel oil system Fuel oil supply system shall consist of the following equipment as a common facility for 2 units.
3.2.2.1
Fuel oil supply system A.
Fuel oil booster pumps and motors
B.
Fuel oil service pumps complete and motors
C.
Clean fuel oil sump pumps and motors
D.
Fuel oil storage tanks with its accessaries
E.
Fuel oil emergency storage tank with its accessaries
F.
Fuel oil in-line suction heaters, fuel oil heaters and fuel oil emergency inline suction heaters
G. Heating coil for fuel oil storage tanks and fuel oil emergency tank H.
Filtering systems
I.
Fuel oil supply system including heat tracing, flow meter and integrator, accumulator, all required piping, valves, drains, vents, fittings, and instrumentation etc.
3.2.2.2 Light oil supply system A.
Oil service pumps complete and motors
B.
Light oil storage tank with its accessaries
C.
Flow meter and integrator, all required piping, valves, actuators and instrumentation
3.2.2.3 Steam converter system A.
Steam converter with accessories
B.
Fuel oil heater converter feed tank with accessories
C.
Steam converter feed pumps and motors
D.
Drain receiver tank with accessories
E.
Drain cooler with accessories
F.
Blowdown tank with accessories
G. Steam converter system including all necessary piping, valves and instrumentations
3-4 KHABAT TPP UNITS 1&2 - VOLUME I
3.2.3
Electrostatic precipitator including A.
All mechanical equipment, structural components and accessories
1) Ash hoppers with vibrators and heaters on each hopper, and exterior siding for hopper area enclosure. 2) Precipitator roof including penthouse and handrail around entire precipitator roof. 3) Gas distribution plates or equivalent at the inlet and outlet sides of precipitator. 4) Collecting electrodes and discharge electrodes. 5) Automatic rapping system for collecting and discharge electrodes and for the gas inlet and the outlet distribution devices. 6) Permanent washing system including chemical(NaOH) tank, pumps, nozzles, pipe for drain between precipitator hopper and air lock valve, drain piping, gate valves and fitting, blinded dummy pipe, supports, expansion joints, spectacle flanges, gaskets, bolts, nuts, instruments and controls, etc. 7) Gas flow control devices in the upstream duct of EP inlet nozzle. 8) Access and inspection doors to precipitator shell, hoppers and top housing, hoisting facilities for maintenance on the roof, and access platforms, walkways, handrails, stairs and ladders 9) Support structures for all equipment, platforms, stairs, walkways and enclosure including bottom enclosure. 10) Access platforms and stairways for level switch, aeration pad and vibrator of hopper and air lock valve. B.
Complete set of electrical, instrumentation and control apparatus and control devices.
C.
The following miscellaneous items ;
1) Piping, valves, fittings and pipe support. 2) Drain pipe and gutter for roof drainage. 3) All flanges, gaskets, bolts and nuts including counter flanges for flanged connections. 4) Thermal insulation and lagging. 5) Hoisting facility to handle the equipment from EP roof to ground. 6) Instruments and test connections for conducting performance tests. 7) Dust concentration monitoring system.
3-5 KHABAT TPP UNITS 1&2 - VOLUME I
3.2.4
Ash handling system A.
The following ash transport system and accessories ;
1) Transport piping 2) Air intake valves 3) Ash intake valves 4) Line select valves 5) Unit select valves 6) Steam air heaters 7) Seal air fan and drivers 8) Electric heater for seal air fan 9) Non-return valves 10) Hot air select valves B.
The following vacuum system and accessories ;
1) Vacuum pumps with drivers, air-water separators, etc for 2 units. 2) Vacuum breakers. 3) Vacuum transmitters. C.
The following ash storage silo and accessories for 2units common facilities.
1) Ash storage silo. 2) Aeration air steam heaters. 3) Cyclone separators with air lock valves(upper and lower),
equalizing
valves, etc. 4) Pulse-jet bag filters with air lock valves(upper and lower), equalizing valves, etc. 5) Dust hopper with valves(upper and lower), equalizing valves, etc. D.
The following ash discharge devices and accessories for 2units common facilities ;
1) Dry unloaders. 2) Outlet hopper with gate dampers. 3) Rotary unloaders/table feeders. 4) Dustless unloaders. E.
Complete set of electrical equipment including related control equipment and accessories.
F.
All heaters, instruments and accessories.
G. All Instrumentation and controls
3-6 KHABAT TPP UNITS 1&2 - VOLUME I
3.2.5
Steam turbine/generator and auxiliaries A.
Tandem compound, single reheat, two(2) flow, regenerating and condensing steam turbine.
B.
The following turbine accessories:
1) Control and protective valve systems including main steam stop valves, reheat stop and intercept valves, and steam control valves. All actuators for these valves shall be supplied. 2) Gland steam sealing system including GSC. 3) Exhaust hood spray system. 4) Complete lubricating oil system including purification, storage and transfer, and fire protection. 5) Complete hydraulic and control oil system. 6) Rotor turning gear with manual and automatic engagement, complete with lubrication system and controls. 7) LP bypass system and devices for turbine startup and protection. 8) Complete prewarming system including piping and valve, if required by design. 9) Protective devices such as exhaust casing relief diaphragms, vacuum breaker, low vacuum alarm switches and transmitter, low oil pressure switches for alarm and trip, thrust bearing wear detector, exhaust hood alarm thermostat, and dump valve (blowdown valve). C.
The following miscellaneous items:
1) Piping and valves including power operated valves, safety valves and relief valves, root valves for instruments, motorized and control valves hangers and supports for all the systems. 2) HP turbine exhaust non-return valves. 3) Set of connections, orifice flanges, and all other items, required for the ASME Performance Test. 4) All pumps required for equipment. 5) A portable lube oil centrifuge (one common to four(4) units) 6) H2 and CO2 gas bottles, bottles rack and manifolds including connecting tube between manifolds and bottles 7) Drain and vent pipe relation with steam seal including connection with condenser for dump drain and lube oil system. 8) Special thermal insulation and lagging materials for turbine. 9) Embedded material (Fixators) 3-7 KHABAT TPP UNITS 1&2 - VOLUME I
10) Electro-hydraulic control oil for flushing until complete commissioning, initial fill, and two(2) years operation. 11) Lubricating oil and seal oil for flushing until complete commissioning, initial fill. 12) Strainer for EHC and lube oil flushing during commissioning. 13) Steam blowdown cover plate for MSV, CRV and HP turbine exhaust non-return valves. 14) Servo Motor mechanism 15) Special welding rods 3.2.6
Condensate system A.
Single shell type condensers
B.
Condensate pumps and motors
C.
Condenser vacuum pumps and motors, heat exchangers
D.
Heaters 1) Low pressure feedwater heaters (No. 1, 2, 3) and external drain cooler for heater No 1 2) The following miscellaneous items : a)
All heater supports including support rails
b)
Tube and shell side safety relief valves, and orifices, as specified herein.
c)
Orifices including gaskets, bolts and nuts, both flanges for pipe line.
d)
A sufficient number of plugs for each tube material and tube size furnished for unit as specified herein.
e)
All valves, level gauges, temperature and pressure instruments, thermowells including heater isolation MOV's
f)
Connections
for
gauge
glasses,
level
and
pressure
instrumentation, and for vents, drains, as required 3) Platform and stairway for the heaters(No. 1, 2, 3 feedwater heater) for inspection and operation 4) Two(2) test samples of tubing of each material, size and thickness supplied. Test pieces shall be 2m in length E.
Stand pipes for the drain of the HP/LP heater relief valves
F.
All associated piping, valves, instrumentation and controls between condenser and inlet deaerator, demi & condensate storage tank, makeup water line to miscellaneous systems, minimum flow recirculation line, condensate rejection line, deaerator level control. 3-8 KHABAT TPP UNITS 1&2 - VOLUME I
3.2.7
Feed water system A. Deaerator and accessories 1) Deaerator including vent condenser with internal spray distribution system and tray banks. 2) Horizontal feedwater storage tank. 3) Connecting downcomers and pressure equalizing pipe between deaerator and feedwater storage tank. 4) Deaerator/feedwater storage tank unit supports. 5) The following miscellaneous items: a) Safety relief valves and orifices b) Feedwater storage tank section with a vortex breaker c) Necessary manholes and access doors d) Pressure relief doors in the tray enclosure e) Platform and stairways around on deaerators/feedwater storage tanks necessary for operation, inspection, maintenance and access f)
Screen for pump suction
g) Deaerator pressure control valves and level control valves B. Boiler feed water pumps 1) Horizontal, centrifugal, double suction, barrel type boiler feed pumps with electric motors and completed with the following accessories: a) Complete Lube oil systems for each boiler feed pump and motor drive b) Shaft seals with complete external and internal cooling water system for each boiler feed water pump c) Vibration monitoring devices for each boiler feed water pump and motors d) Balance drum leak-off water system including pipe work and the relevant gauges e) Warm-up system including flow restriction orifices, piping and temperature measurements with terminal boxes(E-type, dual) f) Cone type flow measuring elements with all accessories, including root valves for each pump. The services of these elements are minimum flow control, pump protection and feedwater flow control g) Temperature detectors for the each boiler feed pumps and motor drives h) Flexible couplings and coupling guards i) Suction basket strainers including fine elements for start-up, coarse 3-9 KHABAT TPP UNITS 1&2 - VOLUME I
elements for normal operation, pressure differential indicating switches and five(5) way valve manifold for startup and normal operation. A five(5) way valve manifold shall be installed between the sensing lines and PDIT 2) The following miscellaneous items : a) Barrel blanking off plates b) Suction and discharge pressure gauges including root valves, pipes, etc c) Redundant pressure transmitters for pump discharge d) Complete reverse rotation detecting system with sensors and signal condition devices e) Instrumentation for boiler feed water pump C. HP Feedwater Heaters and accessories 1) Complete, 100% capacity, U-tube, high pressure, horizontal closed feedwater heaters with integral drain cooling zone and desuperheating zone for each No. 5, 6, 7 HP feedwater heater. 2) The following miscellaneous items : a)
All heater supports including support rails
b)
Tube and shell side safety relief valves, and orifices, as specified herein
c)
Orifices including gaskets, bolts and nuts, both flanges for pipe line
d)
A sufficient number of plugs for each tube material and tube size furnished for unit as specified herein
e)
All valves, level gauges, temperature and pressure instruments, thermowells including heater isolation MOV's
f)
Connections
for
gauge
glasses,
level
and
pressure
instrumentation, and for vents, drains, as required 3) Platform and stairway for the heaters(No. 5, 6, 7 feedwater heater) for inspection and operation 4) Two(2) test samples of tubing of each material, size and thickness supplied. Test pieces shall be 2m in length D. BFP minimum flow control valves and accessories E. Boiler feedwater control valves and accessories F. Instrumentation and controls for feedwater system G. All required complete piping and valves including hangers, supports for feedwater system 3-10 KHABAT TPP UNITS 1&2 - VOLUME I
3.2.8
Main and reheat system A.
Main and reheat steam system is composed with piping and accessories. The main steam system is from the steam generator superheater outlet to the turbine-generator main stop valves. The cold reheat steam system is from turbine exhaust steam to the steam generator reheater inlet. The hot reheat steam system is from the steam generator reheater outlet to the turbine-generator combined reheat valves.
B. The following miscellaneous items : 1) Dump drain and vent Automatic valves for operating and maintenance 2) Pressure and temperature instrument such as transmitter, thermowells, thermocouple 3) Blind flanges, special flanges, blanks and spacers for hydrostatic testing, cleaning and system flushing 4) PQR material for field welding 5) Access holes, half couplings and plugs for radiographic inspection of pipe field welds 3.2.9
Feedwater heater extraction, drain and vent system A. MOVs for extraction line B. One(1) non-return valve for each extraction heaters and two(2) non-return valve for deaerator C. Heater cascading and dump drain control valves D. Safety relief valves and blow off stand pipe for the drain of the HP/LP heater relief valves E. Pressure and temperature instruments such as transmitters, thermowells, thermocouples F. Automatized drain valve & piping for exdtraction line G. Instrumentation and controls H. All required complete piping and valves including hangers, supports for feedwater heater extraction, drain and vent system
3-11 KHABAT TPP UNITS 1&2 - VOLUME I
3.2.10
Auxiliary steam system A. Auxiliary steam headers B. Control valves and desuperheaters for Auxiliary steam C. Instrumentation and controsl
3.2.11
Closed cooling water system A. CCW heat exchangers B. CCW pumps and motors C. CCW header tank with its related pipe work, valves and fill water connection. D. Chemical pot feeders complete with inlet and outlet isolation valves, drain valve, vent valve and charging valve E. Instrumentation and controls F. CCW Sampling system
3.2.12
Circulating water system A. Circulating water pumps B. Cooling tower including blowdown system C. Circulating cooling water pumps D. CW sampling systems E. Condenser tube cleaning system F. All associated piping and valves G. Instrument and cntrols
3.2.13
Compressed air system A. Instrument air system B. Service air system C. Air compressors including intercoolers, aftercoolers, filters, sand seperators. etc D. Capacity Air dryers E. Instument air receivers and service air receivers 3-12 KHABAT TPP UNITS 1&2 - VOLUME I
3.2.14
Water treatment system The following raw water supply system shall consist of the following equipment as a common facilities for 2 units A. Raw supply system and accessories 1) Raw water pumps 2) One(1) 100% Raw water storage tank 3) Intake equipment a) Travelling screen b) Stop gate c) Trash rake d) Screen wash pumps 4) All associated piping, valves, instrumentation and controls B. Raw water system and accessories 1) Cooling tower make-up pumps 2) Raw water transfer pumps 3) Clarifier and agitator 4) Sludge transfer pumps 5) Gravity filters 6) Filter backwash pumps 7) Demi. water supply pumps 8) All internal facilities of clarifier 9) Chemical feed system a) Alum dissolving tank and agitator b) Alum feed tank c) Alum feed pumps d) Caustic mixing tank and agitator with electric heater e) Caustic feed pumps f)
Alum aid dissolving tank and agitator with electric heater
g) Alum aid feed tank h) Alum aid feed pumps C. The following potable water and service water systems and accessories: 1) Potable water pumps 2) Service water pumps 3) Potable water Hydropneumatic water tank 3-13 KHABAT TPP UNITS 1&2 - VOLUME I
4) Service water Hydropneumatic water tank 5) Sodium hypochlorite feed tank and agitator 6) Sodium hypochlorite feed pumps 7) Activated carbon filters for potable 8) Integrating flow meter D. The following makeup demineralizer systems and accessories: 1) Activated carbon filters 2) Cation exchangers 3) Degasifiers, air blowers and silencers 4) Degasified water transfer pumps 5) Anion exchangers 6) Mixed bed ion exchangers 7) Resin traps 8) Regeneration systems a) Acid day tank with visual indication of tank liquid level and acid injection pumps b) Caustic day tank with visual indication of tank liquid level and caustic injection pumps c) Gas scrubber and mixing tees d) Caustic and acid bulk storage tanks with visual indication of tank liquid level e) Caustic unloading & transfer pumps f)
Acid unloading & transfer pumps
g) Regeneration water pumps h) Steam water Heater i)
Electric heaters for caustic storage tanks and day tank
j)
Steam traps
E. The following demi. water transfer system and accessories 1) Demi. water make-up pump for 1 unit 2) Demi. water storage tank for 1 unit F. The following FGD make-up water system and accessories G. The followings shall be included in 1) Connections for sampling 2) Design and supply of piping, valves, fittings and pipe supports 3-14 KHABAT TPP UNITS 1&2 - VOLUME I
3) All piping for acid and caustic unloading and transfer 4) Design and supply of support accessories such as sole plates, sub-sole plates, shims, wedges, foundation anchor bolts and nuts 5) Initial charge of media and chemicals for all filters, exchangers and chemical tanks 6) All flanges, gaskets, bolts and nuts including counter flanges for flange connections. 7) Safety showers and eye washers. 8) Instrumentations and controls. 9) Steps, platforms, ladders or stairs for monitoring and maintenance. 10) Lube oil and/or grease for initial charge of rotating elements. 11) All control components such as current to pneumatic converters, air regulators with filters and gauges, impulse piping and fitting, air tubing and bulkheads, instrument box, tube raceway, etc., all instrument installation materials as required 3.2.15
Chemical feed and sampling system A. The following hydrazine injection system and accessories for main system 1) High density hydrazine tank 2) Low density hydrazine tank 3) Hydrazine feed pumps 4) Graduated gauge glass 5) Agitator and low level switch for each tank 6) Hydrazine metering cylinder 7) Air operated dispensing pump B. The following aqua-ammonia injection system and accessories for main system 1) Ammonia feed pumps 2) Ammonia tank 3) Fume scrubber for each tank 4) Graduated gauge glass 5) Agitator and low level switch for ammonia tank 6) Concentrated ammonia metering cylinder 7) Air operated dispensing pump C. The following phosphate injection system and accessories for main system 1) Phosphate tanks with basket strainer 2) Phosphate feed pumps 3-15 KHABAT TPP UNITS 1&2 - VOLUME I
3) Graduated gauge glass for each tank 4) Agitator and low level switch for each tank D. The following sulfuric acid system and accessories for cooling water system 1) Sulfuric acid tanks 2) Sulfuric acid feed pumps 3) Graduated gauge glass for each tank 4) Agitator and low level switch for each tank E. The following sodium hypochlorite system and accessories for cooling water system 1) Sodium hypochlorite tanks 2) Sodium hypochlorite feed pumps 3) Graduated gauge glass for each tank 4) Agitator and low level switch for each tank F. The following inhibiter system and accessories for cooling water system 1) Inhibiter tanks 2) Inhibiter feed pumps 3) Graduated gauge glass for each tank 4) Agitator and low level switch for each tank G. Instrumentation and controls H. All required complete piping and valves including hangers, supports for the chemical feed system 3.2.16
Auxiliary boiler Auxiliary boiler shall be of the following common facility for 2 units A. Auxiliary boiler feedwater pumps with electric motor drivers B. Auxiliary boiler deaerator and storage tank C. Condensate make-up pumps with electric motor drivers D. Light oil feed pumps with electric motor drivers E. Blowdown tank F. Forced draft fan with driver G. Firing system composed of oil burner and windbox, ignitor, scanners, and local panel H. Air duct with air foil type ventrt meter, flue gas outlet breeching and outlet I.
Long retractable sootblower and rotary sootblowers
J. All instrumentation, control and safeguards, including control panels and all installation materials and including instrumentation and control and sample line covering upto insulatio for freeze protection within Bidder scope 3-16 KHABAT TPP UNITS 1&2 - VOLUME I
K. Flow nozzles and root valves for water analyzing at boiler feed pump discharge, superheater outlet and boiler water L. Insulation of the pipes and equipment and place and steam bracing all feed oil line for freeze protection system within Bidder scope M. Steel stack N. Desuperheater O. Monorail with steel structure fot forced draft fan maintenance 3.2.17
Black start diesel generator including
3.2.17.1Black start diesel generator A. Diesel engine unit B. Combustible air intake system for diesel engine including filter, air cooler C. Exhaust gas system including turbo charger, silencer, expansion joint D. Fuel oil system including pumps, filter(s), day tank, level gage and switches for day tank E. Lubricating oil system including L.O cooler, filters, pumps, preheater, priming L.O pump with one(1) stand-by pump and potable electric L.O pump F. Cooling system including radiator, radiator fans, duct, expansion tank(s), jacket water heater, pump(s) G. Starting air system including air compressor with one(1) stand-by compressor, air receiver H. Small generator sets including cell motor starting device using battery starting I.
Generator unit including exciter
J. Generator neutral earthing resister cubicle K. Steel structure and support for all tanks L. All required instrumentation and accessories including local instruments, control panel, panel instruments and annunciators including motor starter(if required). M. All
required
electric
equipment
and
accessories
including
AVR,
synchronizing equipment with auto synchronizer, meters, control switches N. Programmable microprocessor type protection relay. O. Internal cables mounted on equipment 3.2.17.2The following miscellaneous items : A. Design and supply of measuring instruments within the terminal points as described herein 3-17 KHABAT TPP UNITS 1&2 - VOLUME I
B. Design and supply of support accessories such as base plates, shims, wedges, foundation bolts and nuts, grouting material for engine/generator C. All flanges, gaskets, bolts and nuts including counter flanges for flanged connections D. Grease for initial charge E. Consumable parts and/or materials required for storage, installation and startup testing F. Earthing pads with clamps or studs G. Lift lugs for equipment maintenance H. Fire fighting system for fuel oil day tank 3.2.18
Heating, ventilation and air conditioning systems Heating, ventilation and air conditioning systems for the complete plant and buildings, including air handling units, chiller system, split air conditioner(w/ humidifier), supply or exhaust fans, hot water generator and all equipment and accessories relevant HVAC system.
3.2.19
Fire protection and detection Fire protection and detection system shall consist of the following common facility for 2 units. Fire protection and detection systems for the complete plant and buildings, including fire pumps, buried hydrant system, hydrant outlets, sprinkler systems, deluge water spray system, foam/water deluge /spray systems, hose reel and equipment cabinets, portable extinguishers, alarm panels and control system. Electronic/electrical panel room shall be designed by fire protecting gas system
3.2.20
Cranes and lifting equipment.
3.2.20.1
Cranes
A. Steam turbine building overhead crane and auxiliary hoist, all necessary equipment and accessories B. Raw water pump house overhead crane and auxiliary hoist, all necessary equipment and accessories C. Workshop crane overhead crane with all necessary equipment and accessories D. Boiler Feed Pumps Underhung cranes with all necessary equipment and accessories E. FGD pump room per unit 3-18 KHABAT TPP UNITS 1&2 - VOLUME I
F. Cooling water pump house overhead crane and auxiliary hoist, all necessary equipment and accessories 3.2.20.2
Hoist
A. Monorail hoist as the common facility for the water/waste water treatment building B. Monorail hoist as the common facility for the air compressor C. Monorail hoist for Emergency Diesel Generator D. Monorail hoists for FD Fan E. Monorail hoist for CID Fan. F. Monorail hoist for Air preheater. G. Monorail hoist for Closed Cooling Water Pump H. Monorail hoist for Sealing Air Fan I.
Monorail hoist in absorber area
J. Monorail hoist in GGH area K. Monorail hoist for equipment of limestone slurry preparation building L. Monorail hoist for vacuum belt filter, pump and conveyor in gypsum dewatering building M. Monorail hoist for pump and dehydrator in FGD waste water treatment building N. All Monorail hoist shall be including trolley and lifting devices with all necessary accessories. 3.2.20.3
Miscellaneous item Each crane shall be supplied complete with all equipment and accessories necessary for safe, efficient and reliable operation including the following but not limited to, as applicable.
A. Crane bridge complete with cross travel rails, walkways and access ladders and stairs to operator's cab and to the walkways along the travel rails. B. The travel rails and their accessories C. Wireless remote pendant. Back up shall be hard wired pendant control. D. Automatic audible alarm, when crane is in operation. E. End stops. F. End carriages. G. Traversing cab incorporating the independently driven hoists and the cab traversing gear H. Maintenance platforms and access ladders, where applicable 3-19 KHABAT TPP UNITS 1&2 - VOLUME I
I.
The main lifting gear complete with ropes and hook fittings
J. The auxiliary lifting gear(where required) complete with ropes and hook fittings K. Slings and shackles 3.2.20.4
Electrical equipment
A. Electrically operated thrust or other type electro-magnetic brakes B. Slip-ring or other type variable speed hoist, long travel and traverse driving motors C. Speed control equipment for motions D. Crane electrical equipment protection panel E. Crane electrical equipment and control cubicles complete with contactors, timers, resistance, rotor acceleration relays, limit switches, cables, wiring, anti-condensation heaters, etc. F. Crane lighting, rood lights, warning lights, plugs and sockets complete 3.2.21
Laboratory equipment Laboratory equipment shall consist of the following common facility for 2 units. Refer to the Vol.1 Technical specification para. 6.21
3.2.22
Services gas system Service gas system shall consist of the following common facility for 2 units. A. Nitrogen Gas Cylinders B. H2 Gas Cylinders, if necessary C. CO2 Gas Cylinders, if necessary D. Pressure Regulators E. All necessary pipework and valves, including insulation, cladding and trace heating (if necessary) for all services.
3.2.23
Workshop equipment Workshop equipment shall consist of the following common facility for 2 units. A. Large Lathe B. Medium Lathe C. Radial Drill Machine D. Flore Drill Machine E. Universal Milling Machine F. Band Sawing Machine G. Metal Cutting Sawing Machine 3-20 KHABAT TPP UNITS 1&2 - VOLUME I
H. 1 x GTAW (200a), 1 x SMAW (150a) 1 x GMAW (300a) welding machines & accessories.
Standard tools sets of for all disciplines shall be supplied. (10
Sets for each discipline: welder, elect, inst, mech, controls). 3.2.24
Elevators A. Boiler area B. FGD absorber area
3.2.25
Flue gas desulfurization system A. Absorber system and accessories ; The following equipment shall consist per unit. 1) Absorbers with reaction tank including internal structure 2) Reaction tank agitators and drivers 3) Absorber recirculation pumps and motors 4) Spray headers and internals 5) Spray nozzles 6) Mist eliminators 7) Mist eliminator washing headers and nozzles 8) Gypsum bleed pumps and motors 9) Absorber slurry sump pumps and agitator 10) Density meter pumps and motors with accessories 11) Absorber off-load cleaning system The following equipment shall consist of the common facility for 2 units. 1) Mist eliminator washing water pumps and motors 2) Mist eliminator washing water tank 3) Oxidation air blowers and motors with humidifiers 4) Emergency storage tank with agitator 5) Emergency storage pumps and motors B. Flue gas system and accessories ; The flue gas system shall consist of the following equipment per unit. 1) Gas-gas heater(GGH)s with complete accessories 2) Flue gas ductworks 3) Expansion joints 4) Dampers with drivers and seal air systems 5) Emergency quenching system 6) Purge air fan 3-21 KHABAT TPP UNITS 1&2 - VOLUME I
7) GGH washing water sump agitator & pumps C. Limestone slurry preparation system and accessories The limestone slurry preparation system shall consist of the following equipment as a common facility for 2 units. 1) Limestone powder storage silos with bag filters 2) Screw feeder 3) Limestone solution tanks and agitators 4) Limestone slurry transfer pumps and motors 5) Limestone slurry storage tanks and agitators 6) Limestone slurry feed pumps and motors 7) Limestone slurry preparation area sump pumps and agitator 8) Limestone unloading air compressors with air dryer D. Gypsum dewatering system and accessories The gypsum dewatering system shall consist of the following equipment as a common facility for 2 units. 1) Gypsum dewatering feed tanks with agitators 2) Gypsum dewatering feed pumps and motors 3) 1st stage hydrocyclone 4) Vacuum belt filters with complete accessories 5) Filtrate tanks and agitators 6) Filtrate return pumps & motors 7) 2nd stage hydrocyclone feed pumps and motors 8) 2nd stage hydrocyclone 9) Gypsum dewatering area sump pumps and agitator 10) FGD wastewater blow down tank and agitator 11) FGD wastewater blow down pumps and motors E. FGD waste water treatment system and accessories The FGD waste water treatment system shall consist of the common facility for 2 units. 3.2.26
Waste water treatment system The waste water treatment system shall consist of the following equipment as a common facility for 2 units. A. Normal and abnormal waste water treatment systems and accessories 1) Neutralized water transfer pumps 2) Abnormal waste water pumps 3) Surface aerators for neutralization pond 3-22 KHABAT TPP UNITS 1&2 - VOLUME I
4) Surface aerators for abnormal waste water pond 5) lnternal facilities of clarifier 6) Clarified water pumps 7) Activated carbon filters 8) Filter backwash pumps 9) Sludge pumps 10) Internal facilities of thickener 11) Thickened sludge transfer pumps 12) Dehydrator package with cake hopper 13) Pump room sump pumps 14) Agitator for final pH adjust pond 15) Agitator for thickened sludge storage pond 16) Final disposal channel and accessories 17) Exhaust fan B. Oily waste water treatment system and accessories 1) Pipe skimmer for API oil separator 2) Oil separated water pumps 3) CPI C. Chemical injection system 1) C-Polymer injection tank for dehydrator with dissolving basket, electric heater and agitator 2) C-Polymer injection pumps for dehydrator 3.2.27
Sewage water treatment system The sewage water treatment system shall consist of the following equipment as a common facility for 2 units. A. Sewage water treatment system with accessories B. Final disposal pump C. All associated piping, valves, instrumentation and controls
3.2.28
Sump pump The sump pump shall consist of the following equipment as a common facility for 2 units. A. Sewage water sump pumps 1) Workshop BLDG. sump pumps 2) Administration BLDG. sump pumps 3) Security gate house sump pumps 3-23 KHABAT TPP UNITS 1&2 - VOLUME I
4) FGD control BLDG. sump pumps 5) Operation & maintenance management BLDG. sump pumps 6) Water & waste water treatment BLDG. sump pumps 7) FGD waste water treatment BLDG. sump pumps 8) Unloading entrance gate sump pumps 9) Chiller BLDG. sump pumps 10) Guard tower sump pumps for No. 1, 2, 3 B. Waste water sump pumps 1) Chemical Water Sump Pumps a)
Unit 1 boiler area sump pumps
b)
Unit 2 boiler area sump pumps
c)
Chemical storage area sump pumps
2) Oily water sump pumps a)
Unit 1 turbine BLDG. sump pumps
b)
Unit 2 turbine BLDG. sump pumps
c)
Unit 1 transformer area sump pumps
d)
Unit 2 transformer area sump pumps
e)
Fuel oil storage tank area sump pumps
f)
Fuel & light oil pump house sump pumps
g)
Fuel oil emergency tank sump pumps
h)
Light oil storage tank area sump pumps
i)
Workshop BLDG. sump pumps
j)
Emergency diesel BLDG. sump pumps
k)
Aux. boiler area sump pumps
3) Other sump pumps a) 3.2.29
Raw water intake canal area sump pumps
Plant design and pipings All required complete piping and valves including hangers, supports for Boiler, turbine-generator and all auxiliary system .
3.3
Electrical Equipment A. Totally enclosed, cylindrical rotor type, 3000 rpm synchronous generator B. Excitation system. C. 132 kV air insulated switchgear For specification of these devices, refer to Part 4 Volume 1 Section 4 D. Generator main connections 3-24 KHABAT TPP UNITS 1&2 - VOLUME I
E. Generator circuit breakers F. Main step up transformers G. Unit aux. transformers H. MV/LV transformers I.
Unit and station power supplies, including 6 kV switchgear, LV switchgear, MCCs and building services sub-distribution boards
J. DC supply system including batteries and UPS systems K. Electrical control system and protection L. Earthing and lightning protection M. MV and LV power, control and instrumentation, telephone and emergency cabling systems N. Lighting and small power systems O. Cathodic protection system 3.3.1
All Interface devices to SCADA system master station located at the national control centre (NCC) such as follows: -
Remote terminal unit of SCADA
-
Protection signaling equipment, if req.
-
Microwave radio link equipment
-
Optical Fibre Based PDH/SDH Equipment For specification of these devices, refer to Part 4 Volume 1 Section 10
3.4
Control and Instrumentation
3.4.1
Complete control, protection and monitoring systems for the steam turbine generator and auxiliary.
3.4.2
Complete control, protection and monitoring systems for the steam generator and auxiliary.
3.4.3
Control, monitoring and protection systems for the fuel supply and storage system, condensate system, feedwater system, main and reheat system, feedwater heater extraction, drain & vent system auxiliary steam system, closed cooling water system, circulating system , etc.
3.4.4
Control, monitoring and protection systems for the electrostatic precipitator, ash handling system, FGD system, sootblowing system, condenser tyube cleaning
system,
auxiliary
boiler,
compressed
air
system,
make-up
3-25 KHABAT TPP UNITS 1&2 - VOLUME I
demineralizer system, chemical feed system, water & waste water treatment system, chemical dosing system sampling system HVAC, etc. 3.4.5
Control, monitoring and protection systems for the station electrical systems Plant control system
3.4.6
Distributed Digital Control System(DCS) based Plant Control System (PCS)
3.4.7
Turbine Control System including Digital electronic governor systems, automatic run-up and loading system, turbine stress evaluator, turbine supervisory system, turbine trip system, generator control and monitoring system, generator gas systems.
3.4.8
PLC(Programmable Logic Controller) based the package control systems including LCD station
3.4.9
Central control room/computer room equipment including operator desks, chairs, printers, large screens, digital indicators, clock, CCTV monitors, furniture, etc.
3.4.10 Emergency shut down systems for safe plant running, shut-down and protection. 3.4.11 Interfaces between the PCS and packaged control systems including TCS via hardwired or redudant communication 3.4.12 Condition monitoring equipment for major plant and auxiliaries. 3.4.13 Plant performance system 3.4.14 Instrumentation with accuracy suitable for tariff metering 3.4.15 Gas and water emissions monitoring equipment 3.4.16 Water and steam sampling equipment 3.4.17 Local instrumentation 3.4.18 Instrument power and air distribution systems 3.4.19 Telecommunications systems 3.4.20 Closed circuit television and perimeter security system 3.4.21 Weather station 3.4.22 Fire and gas detection systems 3.4.23 Public address system 3-26 KHABAT TPP UNITS 1&2 - VOLUME I
3.4.24 Electrical and instrument test equipment 3.4.25 All required control and instrumentation for safe, reliable and efficient operation of the plant. 3.4.26 Others as specified in para. 8 “control, instrumentation and communication”.
3.5
Civil Works All civil works associated with the above equipment and facilities, including but not limited to:
3.5.1
Geo-technical and topographical surveys of the site, the raw water intake and discharge area including ground pollution report.
3.5.2
Hydraulic model study report and hydrological survey including water level data in consideration of the seasonal changes in Greater Zab River.
3.5.3
Route survey along the raw water pipe and discharge pipe.
3.5.4
Data collection including verification of design data provided in the tender documents
3.5.5
Enabling works with regard to existing services, earthworks, dewatering and demolitions
3.5.6
Access roads, site roads, paved hardstanding areas (for car parking, concrete slab laydown areas, gravel covered sterile areas, pathways, street lighting and landscaped areas
3.5.7
Utilities pipework
3.5.8
Acoustic attenuation where required to meet noise limits
3.5.9
Storm, sewage, oily and plant drainage systems
3.5.10 Utilities and underground services 3.5.11 Security works during construction and operational phases 3.5.12 Permanent Perimeter fence from concrete block wall with additional security camera system and security lighting. 3.5.13 Heavy duty, large rolling type security gate(s) for road access and small personnel access gate. 3.5.14 Hard landscaping 3-27 KHABAT TPP UNITS 1&2 - VOLUME I
3.5.15 Concrete slabs for miscellaneous pipe supports 3.5.16 Exterior & interior equipment support foundation and foundation accessories such as sole plates, counter flanges with bolts, nuts, gaskets, packing, channel base, sub-sole plates, shims, wedges, foundation anchor bolts, anchor frame and nuts, and grout and embedded materials 3.5.17 Piling works and/or ground improvement 3.5.18 Site services, (i.e., power, water, sewage and telephone,etc.) for the Bidder and KNOC office accommodation during the construction period 3.5.19 Building contents (ironmongery, fixtures and fittings, internal finishes, furniture, office computer equipment, fire and safety equipment) 3.5.20 Mechanical and electrical building services 3.5.21 Builder’s work associated with building services installation 3.5.22 Office accommodation during the construction period for the Bidder, and the KNOC Building works, foundations, structures and associated facilities: 3.5.23 Interfaces with associated contracts 3.5.24 Design, preparation of detailed construction drawings, bar bending schedules and all drawings and documents necessary for completion and maintenance of the works, 3.5.25 Preparation of as-built documentation 3.5.26 Buildings, structures, foundation and compounds to be included as a minimum, in the civil works as follows:
Turbine building
Central control building
Boiler and electrostatic precipitator
Stack
Absorber foundation
Fan foundation
Clean & dirty lube oil tank foundation with dike
Fuel oil & fuel oil emergency, light oil storage tank foundation and dike
Raw water storage tank foundation
Demi. water storage tank foundation 3-28 KHABAT TPP UNITS 1&2 - VOLUME I
Ash silo foundation
Limestone slurry storage & emergence storage tank foundation
Gypsum dewatering feed & filtrate tank foundation
Chemical storage tank and pump foundation with dike
Transformer foundations and compounds (with fire walls and bund walls)
Switch yard area facilities foundation
Raw water supply system complete with raw water intake canal and pump house, pump foundation and piping
Circulating water system structure complete with cooling tower and cooling water pump station
Discharge basin
Sewage treatment facilities foundation
Waste water treatment facilities foundation with pond
Truck scale foundation
Parking
Pipe rack foundation
Play ground
Aux boiler house
Electrical building
Administration building including toilets, small cafeteria
Operations & maintenance management building
Dining facility building
Prayer facility building
First aid center with 2 rooms
Raw water pump house included electrical facilities
Foam tank house
Fire brigade station
Fuel & light oil pump house
Service gas storage house
Workshop building
Warehouse building
Chiller building
Water & waste water treatment building
Security gate house with 2 rooms
Unloading entrance gate house with 2 rooms 3-29 KHABAT TPP UNITS 1&2 - VOLUME I
Sun shades and rain screens
Black start/emergency diesel generator building
Construction office
Gypsum dewatering building
Limestone slurry preparation building
FGD waste water treatment building
FGD pump rooms
FGD control building
Guard towers with personal amenities
Building services, including air conditioning of the local control rooms, central control building, special storage areas, toilets and mess rooms, prayer and cafeteria buildings. Foundations and associated works for:
All buildings, structures and compounds listed above
Steam turbine generators
Transformer compounds
Black start/emergency diesel generator
Fuel oil storage tanks and handling equipment
Service/fire water, potable and demineralized water storage tanks
Fire fighting foam equipment
Compressed air equipment
Miscellaneous plant and equipment
Service ways, silos, ducts and trenches, pipe racks and bridges
All necessary supports, access ladders, stairways, platforms, walkways, sunshades, handrails, etc., for the safety of personnel during plant operation and maintenance
Bunded areas for all lubricating and other oils and chemicals
Rain shelters over all bunded areas
Sump pumps
Sewage water treatment system
3.5.27 General services All necessary services associated with the above scope, including, but not limited to the following: A. Quality control inspection and testing Painting and finishing 3-30 KHABAT TPP UNITS 1&2 - VOLUME I
B. Spare parts C. Tools, lifting tackle and special appliances D. Contract documents and drawings E. Quality Control, inspection and testing F. Operation and maintenance manuals G. Training of the KNOC’s staff in the operation and maintenance of the Works H. Local lifting beams and manual hoists I.
Special tools and maintenance equipment for all plant and equipment
J. All flushing facilities and flushing oils K. All required insulation and lagging materials supply L. Welding rods required for the interconnecting piping and other parts within the Bidder's scope as well as welding specimens required for welder qualification tests and special welding rods M. All instrument nozzles, connections, root valves, sensing lines and their installation materials complete with instrumentation to measure and indicate all fluid conditions N. Enclosures for required systems. These include sound, personnel protection, weather and any other enclosures necessary to ensure a complete operating system O. Safety showers and eye washers P. Stairs and ladders, walkways, handrails, platforms and supports for monitoring, operation and maintenance of all equipment, and tanks, instrumentation, valves, etc. Q. Connections for sampling R. Sump and trench cover plate S. Strainers T. All accessories of concrete pond : walkway, stairway, ladder, polyethylene coated piping sleeve and handrail etc. U. First charge of all chemicals, lubricating oils, lubricants and filters V. Consumable spare parts up to end of the defects liability period The Contract shall include the whole of the aforementioned work which is described in or implied by the Specification and all matters omitted from the Specification which may be inferred to be necessary for the safe, reliable and efficient operation, stability and completion of the Works shall be deemed to be included in the Contract Price. All plant, equipment, materials and works shall
3-31 KHABAT TPP UNITS 1&2 - VOLUME I
be provided to complete the installation ready for commercial operation whether or not specifically called for herein.
3.6
Provision for KNOC Costs -
The Contractor shall provide Funitrue for Admin. Building, Operation & Maintenance Management Building. Furniture will be based on standard office equipment for the number of persons to be accommodated at the site.
-
The Contractor shall provide transportation (air, sea, and inland) and Hotel accomodation for KNOC to carry out the Manufacturing Testing.
The Contractor is requested to apply a ceiling amount of US$ 1,500,000 (one million and five hundred thousand United States Dollars) in the proposal.
3.7
Transfer of resposibilities The Plant shall be handed over to the O&M team on successful completion of performance verification tests. In order to guarantee a smooth and seamless transition of operations and maintenance responsibilities for the Plant from the contractor to the O&M Team it is essential that a detailed “Responsibility Transfer Plan” is developed by the Contractor and jointly agreed with the O&M Team. The success of the transfer process will be heavily influenced by the quality and duration of the training provided to the O&M staff assigned to the Plant. The “Responsibility Transfer Plan” should include the requirement for monitoring and reporting on the progress of the O&M staff assigned to the Project. In addition to the transfer of responsibility in terms of O&M personnel, the overall transfer process should define the process for documentation handover as a part of the overall start up and commissioning of the Plant. Such process must ensure that all relevant documentation and document management systems are fully transferred to the O&M team before the Contractor demobilizes from the site. The Contractor shall have full responsibility for the Plant from design up to final commissioning and handover to the O&M team. It is required that following handover of Plant responsibility to the O&M team, the Contractor shall maintain at site a core team of plant O&M
3-32 KHABAT TPP UNITS 1&2 - VOLUME I
specialists to provide ongoing support to the O&M staff. This support period is expected to last for one month. Responsibilities Chart The contractor shall develop “Responsibility Transfer Plan” including the following contents, but not limited
Overall method and responsibilities
Organization for commissioning and start-up
Support organization during initial operation
Critical design list need of the O&M staff’s review
Factory test process including the O&M staff’s witness of main plant item
Main system list need supervision of the O&M staff
Method and process of the O&M staff’s supervision
Start-up test procedure and handover document list (Drawings, results, O&M Manual)
3.8
As-Built document list
Terminal points The Bidder shall be responsible for the provision of sufficient data regarding the interface conditions for the plant, to ensure the appropriate design of the plant to ensure safe, efficient and reliable operation within the environmental limitations, under all operating modes and climatic conditions as defined in [Section 2]. The Bidder shall assess the proposed termination points for all services and shall agree with the KNOC an appropriate tie-in point and tie-in schedule. The location and schedule shall, where applicable, be designed to minimize inconvenience to other users of the systems.
3.8.1
Fuel supplies The Bidder shall be responsible for the connection of the fuel supplies to agreed termination points located adjacent to the site boundary. The exact location of these termination points will be finalized after award.
3-33 KHABAT TPP UNITS 1&2 - VOLUME I
An indicative analysis of the fuels is included in [Volume 2, Schedule A] for information. However, the Bidder shall be responsible for the provision of sufficient data regarding the fuel supplies for the plant, including analyses as necessary to ensure the appropriate design of treatment and handling/storage facilities to provide the requisite flow and quality of services as required by the boilers and other users within the site. 3.8.2
Water supplies The Bidder shall be responsible for supply the water to the plant from the Great Zab river. An indicative analysis of the raw water is included in [Volume 2, Schedule A] for information. However, the Bidder shall be responsible for the provision of sufficient data regarding the water supplies for the plant, including analyses as necessary to ensure the appropriate design of treatment and handling/storage facilities to provide the requisite flow and quality as required within the site.
3.8.3
Electrical connections Electrical power from each generator shall be exported to, and be compatible with, the electrical connection provided by the MOE. The MOE will supply the connection between 132kV AIS and First Transmission Tower supplied by the MOE. Bidder’s terminal point shall be up to the gantry towers of transmission line sides. Terminal point of OPGW(optical fiber ground wire) shall be same as main connection. The Bidder shall establish communication protocols and liaise with the Ministry of Electricity to ensure that all appropriate safety requirements are fulfilled.
3.8.4
Communications All connections to the public telephone network shall be the responsibility of the Bidder. The Bidder shall ensure that all communication systems used during construction and operation of the Site meet appropriate regulations and do not cause interference with any communication or electrical equipment on the surrounding site.
3.8.5
Drainage The drainage systems shall be sub-divided into surface water, sewage water, chemical and oily water systems.
3-34 KHABAT TPP UNITS 1&2 - VOLUME I
The surface water, sewage water, chemical and oily water treated by each treatment system shall be discharged to river through discharge basin. 3.8.6
Security fencing and access roads The Bidder shall provide site security fencing, access roads and a main site access gate. The Bidder shall also ascertain the requirements of the [Ministry of Electricity] and gas Bidder and provide additional security fencing, access roads and access gates to the gas supply compound and for electrical equipment compound. The detailed requirements of nominated gas Bidder and the [Ministry of Electricity] shall be determined by the Bidder in discussions with the two organizations. Details of the civil engineering work requirements on fencing and access road are provided in Section [9]. The alarm, surveillance and security requirements are detailed in Section [8].
3-35 KHABAT TPP UNITS 1&2 - VOLUME I
4
GENERAL REQUIREMENT
4.1
Project Management
4.1.1
Overall scope The Bidder shall implement and maintain plans, procedures necessary and appropriate for the performance of the work in accordance with the agreement.
4.1.2
Organization The Bidder shall establish and maintain project management team for the proper execution of the project.
4.1.3
Operation of computer system for project management The Bidder shall develop and operate project management computer system to control the detail status which occurs in the course of schedule control, material control, drawing and document control, etc. efficiently. Project management computer system shall be established of networked computers, integrated
software
applications,
organized
databases,
and
web-based
communications. The Bidder shall provide related information to KNOC in timely manner 4.1.4
Project management plan No later than two (2) months after receipt of written Notice to Proceed form KNOC, The Bidder shall submit the Project Management Plan to KNOC for approval. The project management plan shall be described the management approach and philosophy for the project implementation. The project management plan shall be contained detail procedures for the engineering, delivery, subcontract plan, interface coordination, permits, administration, correspondence and other plans The project management plan shall also contain the following a. Project organization - Project organization in terms of participating companies and key individuals - Project organization in terms of each phase of the project(engineering, procurement, construction, commissioning) 4-1 KHABAT TPP UNITS 1&2 - VOLUME I
b.
Engineering management plan - Review and approval category of engineering deliverables - Coordination between KNOC and Bidder (Incl. coordination between Bidder and subBidder) - Interface management with other Bidder’s design - Guidelines for Engineering control procedure - Engineering deliverables and document control - Others (change control, etc.)
c.
Procurement management plan - Material procurement strategy (including subcontracting strategy and qualified subBidder list - Guidelines for Material control procedure (purchasing, expediting and inspection) - Others (Material transportation plan, etc.)
d.
Construction and commissioning management plan - Subcontract management - Use and removal temporary facilities - Detailed construction method statement - Guidelines for material control and handling at site - Plan and schedule for obtaining various statutory permits - Responsibility transfer plan
e.
Project change control plan - Types of change - Change control process - Change control related forms
f.
Risk management plan - Risk definition and concepts
4-2 KHABAT TPP UNITS 1&2 - VOLUME I
- Risk management process - Integration with project management - Risk closure - Opportunity management process - The contractor shall develop the Risk management plan and operate in accordance with the clause 4.13 “Risk management guideline” . g.
Meetings - PRM(Project Review Meeting) The PRM shall be held to review and evaluate the project status and progress, identify the problem areas and establish plans for corrective actions. The contractor shall conduct the meetings. Meeting Frequency: Once a month, in principle, KNOC decides on meeting schedule based upon discussion with the participants. Meeting Place : in Iraq, in principle, KNOC will determine the final selection of the meeting location.
- SRM(Status Review Meeting) The SRM shall be held for the same purpose as the PRM, but its purpose is limited to the entities of a specific contract, or a group of related contracts. In the latter case, the SRM shall be participated by all organizations involved in the group of related contracts. The following SRMs are foreseen: Engineering status review meeting Equipment supply status review meeting Construction status review meeting Meeting Frequency: As needed basis Meeting Place: The participants will take turns hosting the meeting as approved by KNOC in advance.
4-3 KHABAT TPP UNITS 1&2 - VOLUME I
h.
Communication plan - Types of communication - Contact points - Communication matrix - Correspondence forms
i.
Other plans - Document review and approval - Documents Distribution, - Record managements, - etc.
4.1.5
Health, safety and environmental management plan The Bidder shall establish comprehensive plan to identify and manage safety, health, environmental and operational risks in connection with the execution of the Work. The Bidder shall submit the HS&E management plan to KNOC for approval in accordance with schedule E of technical specifications.
The HS&E Management
plan must maximize: a.
Safety and accident prevention
b.
Plant and equipment integrity
c.
Pollution prevention
d.
Energy conservation
e.
Personal, occupational and environmental health
f.
Physical security
g.
Others(HS&E training of EPC Bidder workforce, HS&E Coordinator, Incidents, etc)
The HS&E Management plan shall comply with internationally recognized standards and legislation. The HS&E Management plan shall emphasize “no accidents, no harm to people and no damage to the environment.” The Bidder shall prepare and submit to KNOC a monthly HS&E report covering the activities at site. This report shall contain the following
4-4 KHABAT TPP UNITS 1&2 - VOLUME I
a. A list of all significant hazards observed at the site during the reporting period and a description of risk assessment and corrective actions taken to prevent recurrence of the same type of incident. b.
A list of all injuries/occupational health issues at the work site.
c.
Information showing the number of all injuries, illnesses, lost workday cases, and the number of workdays per month at the site.
d.
4.1.6
Spills/leaks and other Environmental Incidents.
Environmental protection The Bidder shall submit to KNOC within 10 days after his mobilization to the site an environmental protection plan for approval. The Bidder shall maintain vigilance with regards to environmental issues and contingencies and shall follow the provisions of the environmental protection plan as submitted to and approved by the KNOC. Spill prevention, drainage, disposal, pollution, etc. shall be covered by the environmental plan and the Bidder shall execute due care and diligence with regards to environmental protection.
4.1.7
Project quality plan The Bidder shall submit the project quality plan to KNOC for approval in accordance with schedule E of technical specifications. The Bidder shall establish an independent and professionally staffed QA/QC function within the project management team. The Bidder shall develop a QA/QC plan for the engineering, procurement and fabrication, installation phase work.
4.1.8
Training plan for MOE personnel No later than three (3) months receipt of written Notice to Proceed form KNOC, The Bidder shall submit the training plan to KNOC for approval in accordance with training requirements described in Clause 4.9 of technical specifications.
4.1.9
Project control procedures
4.1.9.1 Schedule control procedure
4-5 KHABAT TPP UNITS 1&2 - VOLUME I
No later than one (1) months after receipt of written Notice to Proceed form KNOC, the Bidder shall submit schedule control procedure to KNOC for approval.
The
Schedule Control Procedure shall set forth the procedure for controlling the engineering, procurement and manufacturing, construction and start-up, including sub-contracting, in accordance with the programme and progress described in Clause 4.2 of technical specifications.
The Schedule Control Procedure shall also
contain the following: a.
Organization
b.
Development and operation
c.
Progress measurement
d.
Update and reporting.
4.1.9.2 Material control procedure No later than two (2) months after receipt of written Notice to Proceed form KNOC, the Bidder shall submit the material control procedure to KNOC for approval. The Material Control Procedure shall set forth the procedure for controlling the material status from material purchase request to site storage and installation.
The Material
Control Procedure shall also contain the following. a.
Overview for material control
b.
Responsibility and role
c.
Detail procedure for material control
d.
Providing information and reporting.
4.1.9.3 Project numbering procedure No later than two (2) months receipt of written Notice to Proceed form KNOC, the Bidder shall submit the Project numbering procedure to KNOC for approval. The Bidder shall develop detail project numbering structure based on KKS(Kraftwerk Kennzeichen System). All entities shall use it for numbering of equipment, piping, valves, cable, instrumentation and spares. Plant and equipment items will be identified by a nomenclature system. Project Numbering Procedure shall also contain the following. a.
Work Breakdown Structure
b.
Numbering structure for drawing and document
c.
Numbering structure for equipment and component 4-6 KHABAT TPP UNITS 1&2 - VOLUME I
d.
Activity numbering structure for schedule control (Engineering, Procurement, Construction, Start-up)
e.
Cost control code of account
f.
Others
4.2
Programmes and Progress
4.2.1
Programme requirements The programmes supplied by the Bidder will be used by KNOC to monitor the overall progress of the project. Primavera project management software shall be used for all programmes for the duration of the Contract.
The programmes supplied by the
Bidder as part of this Project shall fully interrelate design, procurement, manufacture, erection and commissioning activities.
Key events shall be clearly identified on all
programmes and be integrated into the program logic. The Bidder shall provide primavera software (version 6.2.1 , 5 licenses) for project management. [ Include training (Intermediate level of competence) of KNOC/MOE’s staff in Iraq ] All programmes issued throughout the Project by the Bidder shall be provided electronically in Primavera format, to allow full interrogation by KNOC.
Print or plot
files will not be acceptable. The approved programme shall be adhered to by the Bidder and shall not be changed except as agreed by KNOC.
If at any time during the execution of the
project it is found necessary to modify the approved programmes, the Bidder shall inform KNOC and submit the modified programmes for his approval.
Any approval
or changes to the approved programmes shall not constitute approval of an extension of the guaranteed completion date, nor any approval of claims for increases in the EPC price. 4.2.1.1 Bidder programme during proposal The Bidder is requested to prepare the Bidder programme considering KNOC’s proposed project milestone schedule The Bidder submission shall be supported by a Bidder programme (bar chart format, level I) conforming with the outline project programme included in this Specification 4-7 KHABAT TPP UNITS 1&2 - VOLUME I
and in sufficient detail to indicate the Bidder’s intention for executing the Works, and must cover major items relating to design, procurement, manufacture, delivery, erection, setting to work and commissioning. shown.
The critical path shall be clearly
Long lead manufacturing items and the dates for placing the main
subcontracts shall be identified. Activity Resources in schedule should also include requirements for special items of plant/equipment such as mobile cranes, oil treatment equipment, welding preheat/post heat equipment, laser alignment equipment etc. to ensure sufficient level of equipment. Contractual Key dates and periods, programme and interface events shall be identified in the Bidder programme, including dates for access data and release of terminal points, that involve the KNOC or other Bidders. Key dates of despatch, delivery to site and completion shall be identified in Schedule B. The Bidder programme shall be resourced with the site labour requirements segregated into trade categories to meet the Bidder Programme. 4.2.1.2 Contract programme during after award The Bidder Programme shall be updated to include any modifications negotiated and agreed during the period up to award of contract and shall have the detail further expanded and developed prior to being submitted for approval by KNOC
within
[30] days after receipt of Notice to Proceed. The programme shall be of at least level 2 detail, resourced and capable of producing manning histograms for each phase of the works, covering design, procurement, manufacture, construction, erection and commissioning.
Activities of
over eight weeks duration are unacceptable and shall be broken down in detail to acceptable sub-tasks.
Following approval by KNOC, this programme shall become
the contract programme, and following the creation of a baseline, shall be used as the basis for measuring and reporting progress throughout the project timescale. The approved contract programme shall be adhered to by the Bidder and shall not be changed, except as agreed by KNOC. If, at any time during the performance of the contract, the Bidder has failed or is seen to be failing to perform the works in accordance with the contract programme, then KNOC may direct the Bidder in 4-8 KHABAT TPP UNITS 1&2 - VOLUME I
writing to allocate additional resources or accelerate the works at the Bidder’s cost. The Bidder shall be instructed to maintain his programme to reflect the current status of progress and to issue the required updated bar charts and associated reports etc, ‘S’ curves and histograms with each monthly progress report. ‘S’ curves shall be directly produced from the contract programme and be based on appropriate quantitative information.
This may include, but not be limited to:
a.
Number of design documents
b.
Quantity of procurement components
c.
Quantity of received materials
d.
Proportion of contract price for each plant area or construction activity
e.
Metres of pipework erected
f.
Metres of cables installed
g.
Number of cable terminations completed
h.
Commissioning packages.
4.2.1.3 Design schedule The Contract Programme shall incorporate design activities that identify the sequence of work for the project and the submission of drawings, studies and reports etc.
The Design Schedule shall be electronically extracted from the
Contract Programme and shall contain all major documents and drawings to be submitted for review by KNOC, their submission dates and durations for review as specified by KNOC, and shall meet the requirements of the Bidder and other Bidders engaged on the project. 4.2.1.4 Procurement and manufacturing schedule The Contract Programme shall incorporate a Procurement and Manufacturing Schedule, which identifies as a minimum: a.
Details of suborders and target dates for placing subcontracts
b.
Any detailed design required within the manufacturing period
c.
Long delivery items.
d.
Information to be supplied by the KNOC submission dates.
The Procurement and Manufacturing Schedule shall be electronically extracted from 4-9 KHABAT TPP UNITS 1&2 - VOLUME I
the Contract Programme and shall be in sufficient detail to enable the work to be adequately progressed.
This schedule shall meet the requirements of the Bidder
and other Bidders engaged on the project. 4.2.1.5 Preliminary Construction Schedule The Contract Programme shall incorporate a preliminary construction schedule, which should identify in sufficient detail the Bidders intended construction strategy. The programme shall satisfy the following criteria: a.
Contain full details of all civil/mechanical/electrical terminal point release requirements.
b.
Identify when services are required for commissioning purposes.
c.
Include an outline setting to work and commissioning schedule.
The Preliminary Construction Schedule shall be electronically extracted from the Contract Programme. 4.2.1.6 Construction schedule Within 60 days after receipt of Notice to Proceed, the Contract Programme shall incorporate a detailed level 3 Construction Schedule, expanding the detail in the Preliminary Construction Schedule and be electronically extracted from the Contract Programme.
In addition to the detail outlined in 4.2.1.5, this schedule shall be in
sufficient detail as agreed by KNOC, to enable the work to be adequately progressed and monitored.
This to include long duration activities of over 30 days
to be broken down into sub-tasks of no more than 30 days duration.
This schedule
shall meet the requirements of the Bidder and other Bidders engaged on the project. 4.2.1.7 Commissioning schedule During the progress of the works, the Bidder shall develop the outline setting to work and commissioning schedule into a detailed level 3 Commissioning Schedule, in sufficient detail to enable the work to be adequately progressed. Activities of over two weeks duration are unacceptable and shall be broken down into acceptable subtasks.
This schedule shall be electronically extracted from the Contract Programme
and submitted to KNOC for approval 3 months prior to the start of any commissioning activities and shall be approved not later than 1 month before the start of any commissioning activities.
This schedule shall meet the requirements of
the Bidder and other Bidders engaged on the project, and shall be integrated with 4-10 KHABAT TPP UNITS 1&2 - VOLUME I
the contract programme. 4.2.2
Progress reporting Monthly progress reports shall be produced by the Bidder and submitted to the KNOC from the commencement of the Contract.
The format is to be approved by
KNOC. They shall be submitted within one week of the report cut-off date to be agreed during negotiations.
The report shall address design, procurement,
manufacturing, construction, setting to work and commissioning issues.
The
reports shall include but not be limited to the following: a.
Executive summary.
b.
Schedule of forecast and actual key events.
c.
Three month look-ahead programme (extracted from the Contract Programme).
d.
Progress to date in narrative format.
e.
Areas of concern and details of corrective action being taken.
f.
Actual resources against planned.
g.
Updated ‘S’ curve.
h.
Issue Register update
i.
Critical Items Report
j.
Contract programme updated to show progress achieved. Programme progress updates
shall also be provided in the form of a fully working Primavera
electronic file, which will allow analysis by KNOC.
Electronic print or plot file
are not acceptable. k.
Planning and consents.
l.
Safety issues and industrial relations.
m. Colour photographs of progress in digital format. Each set shall comprise a total of 20 colour photographs, individually marked with the date taken, a description of the subject and the direction of view. n.
Contract financial status.
The Bidder may be required to include additional schedules and charts considered necessary by KNOC to adequately monitor the Contract. Hard copies of progress reports are to be issued to the KNOC in accordance with Schedule E. An electronic copy shall also be submitted to the KNOC. Following mobilization at site, the Bidder’s site office shall submit weekly progress reports to KNOC in accordance with Schedule E. The report shall summarize site 4-11 KHABAT TPP UNITS 1&2 - VOLUME I
activities, indicate numbers of the various classes of workmen employed on site, the plant and equipment on site and record any areas of concern and details of corrective action being taken.
Daily activity reports shall also be provided
summarizing the main activities to be undertaken each day, noting any special activities that require witnessing, together with full particulars and details of all obstructions, modified or additional work, incidents and the number of men employed in each of the several portions of the work in progress, in accordance with Schedule E. Access to the Bidder’s or subBidder’s works shall be granted to KNOC at any reasonable time for the purposes of ascertaining progress. KNOC shall also have access to the Bidder’s daily activity reports. The Bidder shall provide more frequent updates of schedule as required by KNOC if deemed necessary. KNOC may request the Bidder to provide additional reports when in his opinion they are warranted. Where there is an agreement to pay by time and material rates, the Bidder shall keep records of labour, materials and equipment.
Such records shall be valid only
when signed by both parties. For work of a disputed or uncertain nature, sheets shall be signed by both parties as an agreed record of work done.
The sheets shall be annotated “For record
purposes only” and shall not imply any commitment concerning payment. 4.3
Design and Standardization The Works shall be designed to ensure satisfactory operation in which continuity of service is the first consideration and to facilitate inspection, cleaning and repairs. All equipment supplied shall be designed to ensure safe and satisfactory operation under the atmospheric conditions prevailing at the Site, and under such variations of load and pressure as may be met with under working conditions. In doing so the Bidder shall be responsible for and shall carry out HAZOP studies or other studies deemed necessary by KNOC as part of the design process.
The Works and all
equipment and materials forming part of this Contract shall comply in all respects with any relevant statutory regulations, by-laws or orders currently in force where the 4-12 KHABAT TPP UNITS 1&2 - VOLUME I
Plant is to be erected. Although the Works shall generally comply with international standards, any instruction in this Specification that a particular aspect of the Works shall comply with a named code or standard shall take precedence, and that particular aspect of the Works shall comply with the named code or standard.
International standards
are those standards such as BS, IEC, ISO, ANSI/ASME, API, NFPA, JIS, TRD, DIN and EN which are in common use throughout the world for this type of application. In the event of any conflict in standards, the hierarchy of standards shall be as follows, with the standards occurring first in the list taking precedence over any standards later in the list: a.
Standards named in the Specification
b.
International Standards
c.
Other standards approved by KNOC.
The Bidder may offer Works which comply with international standards, or internationally recognized codes or standards, which differ from those specified. However the Bidder may offer Works which comply with the different standards or codes only if he is able to demonstrate to KNOC’s satisfaction that the Works offered are equal or superior to that which would have resulted had the specified code or standard been used. This substitution of codes or standards for those specified will only be acceptable if the manufacturing organization in question has extensive experience with the alternative code or standard offered.
If requested to do so by
KNOC, the Bidder shall supply to KNOC, at his own cost, two copies in English of the relevant code or standard which he proposes to substitute for that specified. The Bidder shall be responsible for ensuring that all standards used are current, the use of superseded or obsolete standards is unacceptable. The ruling date for current standards are those in place at the time of Contract signature. The Bidder shall be responsible for submitting all statutory calculations for the third party verification and for all other calculations required by KNOC. The International System of Units (SI) shall be used in connection with this Contract 4-13 KHABAT TPP UNITS 1&2 - VOLUME I
and the provisions of ISO 31 and ISO 1000. All materials, fittings, components, items of plant and equipment supplied for incorporation in the Works shall be standardized accordingly. If, after making diligent enquiries, the Bidder is unable to obtain an item standardized in SI units, written approval shall be obtained from KNOC to supply non-standard material. The principal units shall be as follows: Parameter
Units
Pressure
Remarks
bar absolute
All calculations relating to plant performance
bar gauge
All pressure gauges
millibar Temperature
Gauges below atmospheric pressure
°C
Volume
l
(m3)
litre
Mass
kg
(t)
(metric tonne)
Flow – mass
kg/s
(t/h)
Flow volume
l/s
(m3/h)
Flow – gas
kg/s
(Nm3/h)
Rotational speed
rpm
Power
kW
Enthalpy
kJ/kg
Vibration
mm
Head
m of H2O
Heat rate Emissions level
(measured at 0°C 1.013 bar a)
(MJ/Nm3) (amplitude peak to peak) (mm Hg)
kJ/kWh mg/m3
Alternative units indicated in brackets, may be used with the agreement of KNOC. SI units shall be used in all correspondence, documentation, calculations, drawings, measurements etc. If reference has to be made to non-standard items, the SI units shall be quoted followed by the non-standard units in brackets. The Bidder shall standardize mechanical and electrical equipment as well as instrumentation. Corresponding parts shall be made to gauge and shall be interchangeable wherever possible. When required by KNOC the Bidder shall prove this quality by actually interchanging the various parts.
4-14 KHABAT TPP UNITS 1&2 - VOLUME I
Particular attention must be paid to internal and external access in order to facilitate inspection, cleaning and maintenance. The Works shall be arranged such that each major item, plant, or group of minor plant items, can be safely isolated from all hazards for maintenance, if necessary, whilst the remainder of the plant remains in service. The design shall conform to the best current engineering practice.
All plant shall be
of the manufacturer’s standard design, provided that this design is in general accordance with the Specification and shall use components proven to be satisfactory by previous experience. The design dimensions and materials of all parts shall be such that they will not suffer damage as a result of stresses under the most severe service conditions. The materials used in the construction of the Plant shall be of the highest quality and selected particularly to meet the duties required of them. designed and constructed to minimize corrosion.
The plant shall be
Workmanship and general finish
shall be of the highest class throughout. All equipment shall be designed to minimize the risk of fire and damage which may be caused in the event of fire. The equipment shall also be designed to prevent ingress of all vermin, accidental contact with electrical live parts and minimize the ingress of dust and dirt. The Bidder shall provide the services of an approved Classification Society or Insurance Inspection Company subject to KNOC’s approval and which shall include: a.
the certification of designs and drawings and the checking of scantlings of the components of pressure and vacuum containing parts
b.
the certification of designs and drawings of lifting equipment and any other items of plant and equipment which in the opinion of KNOC requires insurance inspection
c.
the inspection and certification that all such components and plant items are manufactured, constructed and tested in accordance with the accepted standards
4-15 KHABAT TPP UNITS 1&2 - VOLUME I
d.
the inspection and certification of pressure or vacuum containing parts, lifting equipment, welding and associated non-destructive testing of such welding, during erection and commissioning on Site.
All certificates shall be distributed in accordance with the requirements of this Specification.
4.4
Drawings and Documents
4.4.1
Drawings enclosed with the Specification A list of the drawings to be read in conjunction with the Specification is given in Volume 3.
The drawings issued by KNOC with the Tender Specification and
forming part of the documents for tendering purposes are intended to be descriptive of the character of the Works and used in conjunction with the requirements of the Tender Specification and shall in no way limit the responsibility of the Bidder to supply all plant and equipment and services necessary to provide for a complete and functional complex. Any omission from either drawings and/or the Tender Specification or express reference to any detail or work necessary and obviously intended shall not relieve the Bidder of his responsibility to include that detail or work. The sizes of the buildings shown on the Tender Specification drawings are approximate, since the actual size will depend on the size and shape of the plant, equipment and materials forming the Bidder’s Works and the space required for installation, maintenance, lay down, storage, access, etc. When measurements are affected by conditions already established, the Bidder shall take and be responsible for field measurements notwithstanding any information given on the Tender Specification Drawings. 4.4.2
Schedules The following technical schedules, contained in Volume 2, have been prepared on IBM compatible computers using Microsoft Word and Excel, and are available via CD ROM. Schedule A
Site particulars 4-16 KHABAT TPP UNITS 1&2 - VOLUME I
Schedule B
Dates of despatch, delivery to site and completion
Schedule C
Manufacturer’s technical particulars
Schedule D
Suppliers of materials, manufacturers, places of manufacture, testing and inspection
Schedule E
Drawings and documentation
Schedule F
Deviations from Conditions of Contract or from Specification
Schedule G
Tests and inspections
Schedule H
List of spare parts and operational consumables
Schedule J
List of special tools
The Bidder is required to complete the required technical schedules (including prices, where applicable) and return these via CD ROM with the completed schedules of their Tender.
A signed print out of the schedules shall be used as original.
The
completed schedules have precedence over the disks. The details provided in Schedule C1 – Manufacturer’s Guarantee Particulars shall take precedence over any other technical information provided in the Tender. Schedule F (Deviations from Conditions of Contract or from Specification) has been prepared on Microsoft Excel on the CD ROM. Bidders are required to complete and return all Comments and Deviations on a CD using the format as provided, ensuring that all items are referenced to the relevant Volume/Section and Page of the Specification, and are uniquely numbered. Unless a specific variation is detailed in Schedule F, the Bidder shall be deemed to comply fully with the requirements of the Specification. 4.4.3
Drawings and documents to be submitted by the Tender A list of the drawings and documents to be included within his Tender is included in Schedule E.
4.4.4
Drawings and documents to be submitted by the Bidder A list of the drawings and documents to be submitted by the Bidder during the Contract implementation stage is specified in Schedule E. The Bidder shall also submit any further drawings or documents as may be reasonably required by KNOC, 4-17 KHABAT TPP UNITS 1&2 - VOLUME I
during the design and construction of the Works.
The Bidder shall prepare and
submit to KNOC review drawings (including dimensioned general arrangement, layout and detailed design drawings), and documents (including schematics, Process and Instrumentation Diagrams (P&IDs), data sheets, descriptions, plans and schedules) of all the plant and equipment specified in the Specification. Drawings and documents already submitted by the Bidder and reviewed by KNOC, and such drawings and documents as shall be thereafter submitted by the Bidder and reviewed by KNOC, shall not be departed from without the written instructions of KNOC. Copies of each drawing, calculation and data shall be submitted in accordance with the programme given in the Schedule of Contract Drawings. If the Bidder requires early review of any drawing or document to avoid delay in the delivery of the Contract Works, he shall advise KNOC to such effect when submitting the drawing or documents.
The sequence of submission of items shall be such that all
information necessary for assessing each item is available at the time when received. In all cases, the drawings or documents shall be submitted in sufficient time to permit modifications to be made if such are deemed necessary by KNOC without delaying the delivery of the Contract Works. As soon as practicable, and not later than 20 working days after receipt, KNOC will advise the category of the drawing as “Reviewed”, “Reviewed as Noted”, or “Returned for Correction”, as may be appropriate. The categories “Reviewed” and “Reviewed as Noted” authorize the Bidder to proceed with manufacture of the equipment covered by such drawings subject to the corrections, if any, indicated thereon.
Where prints of drawings have been “Returned for Correction”, or
“Reviewed as Noted” the Bidder shall make the necessary revisions on the drawings and submit further copies for approval in the same procedure as for the original submission of drawings. Drawings shall be submitted for review at all stages of revision. The Bidder shall supply copies of each drawing for revision as detailed in the appropriate Schedule. Following review, additional copies shall be provided for use at Site as required by KNOC.
4-18 KHABAT TPP UNITS 1&2 - VOLUME I
All dimensions marked on drawings are to be considered correct, although measurements by scale may differ there from. Detailed drawings reviewed by KNOC are to be acted upon where they differ from the general drawings. Drawings showing the physical location of all devices and a plot plan showing the location of all equipment shall be provided. Drawings shall not be “typical” but shall actually represent the equipment provided. Drawings shall be corrected to “as built” before final unit acceptance. “Review” of drawings shall not relieve the Bidder of any of his obligations under the Contract. All legends and notes on drawings provided by the Bidder shall be in the English language. All drawings shall be dimensioned in millimetres (or metres) and drawn to one of the preferred scales quoted in Table 7 of BS Publication PD6031 and on paper of the appropriate size from the International series of A sizes. 4.4.5
Drawings and document format Each drawing and document shall bear a unique drawing/document number. Individual items of equipment forming a part of a drawing shall be clearly identified by means of tables or other approved methods. Each drawing shall incorporate the following information: a.
Location.
b.
Drawing title (shall contain no abbreviations).
c.
Original drawing sheet size ie A0, A1, A2, A3 or A4.
d.
Drawing status.
e.
Drawing number with provision for sheet and revision suffixes.
f.
Drawing date.
g.
Identity of persons carrying out the draughting, checking and approval.
h.
Scale or not to scale.
i.
Project/contract number.
j.
Revision.
k.
North point on geographically related drawings.
KNOC’s information shall be in the form of KNOC’s Drawing Information Box.
This
box shall be located at the bottom right-hand corner of the drawing. 4-19 KHABAT TPP UNITS 1&2 - VOLUME I
Documents submitted for review or approval shall incorporate the following information:
4.4.6
a.
Document title (shall contain no abbreviations)
b.
Document status
c.
Document number
d.
Identity of person carrying out the preparation, checking and approval
e.
Project/Contract number
f.
Revision.
Drawing sheet numbers All drawings shall have a two digit sheet number. Where only one sheet exists the sheet number shall be 00, where more than one sheet exists the sheets shall be numbered from 01 to 99 accordingly.
4.4.7
Drawing and document revision All drawings and documents shall have a two digit revision number and all changes shall be clearly indicated by the addition of the following: appropriate revision number, revision date; identity of persons carrying out the draughting, checking and approval; concise details of the modification. First issues have a revision status of 00, subsequent changes shall increase the revision status from 01 to 99 accordingly. The change of drawing status shall result in a revision increase of one, whether there are changes to the drawing or not.
4.4.8
Drawing and document status Status definitions shall be used on all drawings and documents. not be part of the drawing or document title. a.
For approval
b.
For review
The status shall
The definitions are as follows:
4-20 KHABAT TPP UNITS 1&2 - VOLUME I
c.
For information (for non-project/contract drawings)
d.
For tender purposes
e.
For construction (includes manufacturing)
f.
As built and records.
All revisions of drawings shall be submitted in the following formats as detailed below: a.
A contract drawing list giving the Contract number, manufacturer’s number, sheet number, revision and title of each drawings.
b.
Paper prints of each drawing - full size.
c.
Paper prints of each drawing - A3 size.
d.
AutoCAD ACAD 2000 drawing file.
e.
Drawings in PDF format.
The Contract drawing list shall be submitted by the Bidder for review by KNOC who will indicate thereon KNOC’s requirements. On completion of commissioning, all drawings shall be updated and marked ‘as built’. These shall be supplied as final record drawings. The AutoCAD ACAD 2000 drawing files referred to above shall be imported and exported on media such as Digital Linear Type (DLT) or CD.
Each media shall be
clearly labeled and accompanied by a transmittal sheet showing all file details. Where the file format is restricted, the transmittal sheet shall clearly show how filenames relate to drawing numbers. 4.5
Operating and Maintenance Instructions The Bidder shall supply complete and detailed Operating and Maintenance manuals in English covering the operation and maintenance of the plant and equipment as required by the Contract. The contents of the operating and maintenance instructions, together with all drawings, illustrations and diagrams shall refer specifically to the plant and equipment being supplied under the Contract, and shall be specially prepared where necessary.
General instructions referring to a range of equipment is not acceptable. 4-21 KHABAT TPP UNITS 1&2 - VOLUME I
Operating instructions shall detail all integrated plant normal pre-start checks, starting up, running and shutting down procedures, for the various modes of operation of the plant from cold, warm or hot conditions, emergency operating procedures and any precautions recommended to prevent plant deterioration during periods of non-operation. Operating instructions shall cover local/remote and manual modes of operation and shall also include action on receipt of alarms. The Bidder shall prepare a comprehensive commissioning schedule for each plant item and check lists to record the completion of these activities.
Copies of all
settings and/or calibrations of instruments and controls, pressure switches, trips and alarm settings confirmed and recorded in the commissioning schedules shall be forwarded to be included in the Operating Instructions. [15]sets of draft copies of the manuals shall be submitted to KNOC for review [6] months before commissioning commences. texts.
They shall be submitted as complete
In the event that amendments or alterations to the draft manuals are required,
the Bidder shall submit revisions for review without delay so that the final documents can be supplied within the date specified. [15]sets of the final documents shall be submitted within [4] months after the Taking Over Certificate. The whole of the operating and maintenance instructions shall be securely bound in approved covers and provided with an index for easy reference. The O&M manuals shall be provided in paper hard copy and in electronic copy on CD-ROM to a standard document reader format (ie Adobe Acrobat Reader). The instruction manuals shall conform to the following format: a.
Index The index system shall provide rapid and easy access to particular subjects, drawings and illustrations. It should include a master index and a sub-index to each main section of the manual.
b.
Description This section shall include basic data on the Plant.
4-22 KHABAT TPP UNITS 1&2 - VOLUME I
i.
Descriptions of the Plant both for individual items and for the systems into which items are assembled.
ii.
Drawings sufficient for the understanding of descriptions.
iii. Flow sheets or single line and block diagrams which explain the functioning and logic of the system.
Where related systems are shown on composite
diagrams, individual systems shall be identified by colour, or coding as agreed. iv. Schedules which assemble references to items of a like kind, eg valve schedules, piping schedule, operational limit schedule, switchboard outline schedule, etc. v.
Data sheets which assemble in a concise format relevant technical details of a plant item or system.
The purpose of a data sheet is to provide quick
reference to the essential facts omitting all reference to general descriptions, operating or maintaining principles and instructions. c.
Operation This section shall include basic step-by-step instructions on how to operate the Plant both with regard to individual items and to systems under all patterns of normal and abnormal conditions. The instructions shall include reference to the applicable operation limits. Precautions and warnings relative to the safety of life and equipment shall be included where relevant.
d.
Maintenance This section shall include the following: i.
Build-up and assembly of systems and description of plant items.
ii.
Schedule of equipment giving manufacturer’s name, the make/model No/catalogue No and parts list including any special spares ordering instructions. Spare parts catalogues shall be provided for the various items of equipment supplied.
iii. Routine maintenance schedule. iv. Preventative maintenance and schedule of inspections. v.
Details necessary to carry out overhauls.
vi. Details necessary to locate and rectify faults. 4-23 KHABAT TPP UNITS 1&2 - VOLUME I
vii. Details necessary to set up, test and adjust plant systems and plant items. To include as a minimum, fuel systems, cranage, ventilation, fire protection, water treatment plant and compressed air equipment. viii. Spares schedule. ix. Schedule of recommended lubricants. x.
Sectional drawings of major items of plant fired boiler, steam turbine, condensers, pumps, valves, electric generators, transformers etc with dismantling instructions.
xi. As built copies of all relevant drawings corrected as necessary to incorporate any late modifications. xii. Plant layout drawing. xiii. Schematic diagrams and general arrangement drawings of “as-built” control panels. xiv. Wiring and cable diagrams. xv. Plant equipment and performance curves. xvi. Lifting gear register. xvii. The final records shall include the construction and pre-commissioning data dossier with signed record sheets. e.
Spare parts This section shall comprise the definite and optional spares as required by the KNOC and the spares as recommended by the Bidder. Details and full ordering procedures for each item of main plant, auxiliary plant, electrical and C&I equipment and vendor equipment and shall include: i.
Spare part lists together with referenced sectional drawings from which the manufacturers descriptive name and part number can be clearly identified for ordering purposes.
ii.
Clear details of spare part suppliers address, spare part ordering procedure and including all appropriate plan item reference numbers including serial numbers, type reference numbers, original order numbers, etc as required for the immediate and correct supply of spare parts from various original plant suppliers.
4-24 KHABAT TPP UNITS 1&2 - VOLUME I
In this context the term “suppliers address” means the sub-vendor or original equipment manufacturer.
It will not be acceptable for the Bidder to
nominate himself as the supplier of a spare part unless he manufactures the particular equipment, or it is manufactured by a third party in accordance with the Bidder’s own manufacturing drawings. iii. A list of spares for each type of overhaul/inspection shall be provided. Note: where spare parts are not available and full item replacement is necessary this fact is to be advised and the appropriate ordering details provided as defined above. For spares that are available from a multitude of sources (eg seals, “O” rings, gaskets, nuts, bolts, etc the Bidder shall supply details of the sizes, standards and materials used. Details shall be provided of any special storage requirements or limitations on spare parts, lead time, shelf life, storage requirement, quantity etc. f.
Plant preservation schedule and methods This section shall cover the procedures for shutting down plant.
Preservation
during hibernation and re-starting of plant. g.
Manual production Accepted abbreviations of units of measurement are permitted in the text and illustrations. A list of the abbreviations the Bidder proposes to use in the text and schedules is to be approved before work begins on the manuals. As a guide it may be taken that abbreviations of terms will be permitted only where they are in common use and readily understood, eg ac, dc. Drawings and diagrams shall, wherever practicable, be reduced to a convenient size, eg A3, and bound into the manual.
The reduced size drawings and
diagrams shall be completely legible and suitable for reproduction.
Drawings
which are referred to several times in the text shall be either of the “fold out” type or visible when referring to other parts of a manual or be repeated as
4-25 KHABAT TPP UNITS 1&2 - VOLUME I
necessary.
Throw-clear drawings are to be included at the back of the relevant
subsections, and their locations noted in the Section drawing index. Detailed engineering drawings necessary for maintenance and mentioned in the text but not included in the manual because of size reduction difficulties, should nevertheless be listed in the drawing index. The words “NOT INCLUDED” must be entered against them. Drawings are to be identified at the bottom right corner by title and number. Black on white line drawings should be used wherever possible, using line shading, and cross hatching as necessary for clarity. Multi-colour and half-tone drawings using shading techniques, eg air brush, should only be used in preference to line drawings where the additional information conveyed justifies the effort and cost. Isometric and perspective illustrations are preferred to engineering (orthographic) drawings, although engineering drawings may be included if they are more suitable due to the size and complexity of a particular item of equipment.
Where engineering drawings are used, clarify of detail
necessary to support the text shall be retained and in addition all irrelevant information such as unnecessary dimensions, manufacturing information, borders, centre lines, etc should be removed.
All drawings shall be clearly
marked by legend. The manuals shall be produced as a book or books, with page size international A4, bound into strong durable covers inscribed upon the front generally in the form of the title page to the Specification, except that the references to the contents will be replaced by “Operation and Maintenance Instructions”. Bidders standard pattern covers may be used, subject to KNOC’s approval. The name of the main Bidder but not that of any subBidder may also be inscribed upon the cover after the description of the Plant. The name of the KNOC, the title of the project and Contract number followed by a brief description of the Plant (eg turbo-generator plant, etc) shall be inscribed upon the spine of the cover. If the text is bulky it shall be divided into conveniently sized volumes, and each shall be marked with the appropriate volume number. 4-26 KHABAT TPP UNITS 1&2 - VOLUME I
4.6
HAZOP Studies The design of the plant shall take into account good engineering practice with an emphasis on safe and efficient operation and maintenance practices.
The Bidder
shall perform hazard and operability (HAZOP) studies to demonstrate to KNOC that where possible all risks concerning safe and efficient construction, operation and maintenance have been identified and solutions implemented to eliminate such risks. In the event that the HAZOP studies identify residual risks which cannot be avoided, the Bidder shall incorporate measures in the design, implementation and project documentation (O&M Manuals) to ensure that the effects of the risk is mitigated and the likely effects on the operating personnel, the environment etc are minimized. KNOC shall be provided the opportunity to participate in the HAZOP reviews. 4.7
Places of Manufacture, Testing and Inspection The manufacturers and the places of manufacture, testing and inspection before shipment for the various portions of the Works shall be as stated in Schedule D. As soon as practicable after entering into the Contract, the Bidder shall, having obtained KNOC's consent in accordance with the Conditions of Contract, enter into the subcontracts he considers necessary for the satisfactory completion of the Works.
4.8
Packing and Marking on Packages All apparatus shall be carefully packed for export shipment and storage at site in such a manner that it is protected against all climatic conditions, which shall be as stated in Section 6.25. The packing cases and packing materials are included in the Contract and shall become the property of the KNOC. Key equipment shall be transported with monitoring dew meters within each transport case.
4.9
Training The Bidder shall provide training for the MOE/KNOC’s staff, and give the price in his Bidder, as required in the EPC Contract.
The price shall assume for [172] man-
weeks of offshore training and [198] man-weeks of onshore training.
4-27 KHABAT TPP UNITS 1&2 - VOLUME I
4.9.1
General The Works shall include for separate training sessions for operating and for maintenance staff. Such training shall be at the Bidder’s expense and to an agreed pre-scheduled programme.
The level of training shall be suitable for each member
of staff to ensure individual competence in the overall operation, troubleshooting, protection
schematic,
interlock
matrix,
maintenance,
administration
and
management of the Power Station. The Bidder will be responsible for the planning and co-ordination of the training in conjunction with KNOC.
A fully detailed training
programme with dates shall be submitted to KNOC for approval [4] months after award of the Contract. The training shall be ongoing during the testing and commissioning period so as to ensure that operating and maintenance instructions have been given on all commissioned plant items handed over to MOE/KNOC.
4.9.2
Contents of training The Bidder shall implement following training program for personnel from the MOE's Generation Department. Training will be in English language however a Kurdish translator will be required during Onshore training to assist with technical explanation.
4.9.2.1 Plant management training The Bidder shall conduct a minimum of 40 man weeks Offshore Plant Management Training(4 weeks × 10 MOE Personnel). This training program will cover the following topics: a. Power Plant Construction Management. b. Power Plant Operational Management; Concepts & items necessaries for successful management. c. Power Plant Management; Developing Procedures effectively. d. Performance Power Plant Management taken from existing overseas Power Plants. e. World Thermal Plant Residual Oil & HFO market overview and fuel consumption procurement strategy. f. Power Plant Quality. g. World Power Generation Business Status and Outlook. This training program will be conducted within execution of the Contract the first year.
4-28 KHABAT TPP UNITS 1&2 - VOLUME I
4.9.2.2 Plant operations training Offshore Training:The Bidder shall conduct a minimum of 60 man weeks of Offshore Plant Operations (4 weeks × 15 MOE Personnel). The training will be conducted at the manufacturing facility. At least 70 percent of the training program will be conducted in a classroom. The instruction will be evenly divided between the following: a. Electricity and Thermal Power Plant Generation and Transmission. b. Steam Turbine Generator and Excitation Equipment. c. Oil Fired Boiler Operation and Emissions (including Flue Gas treatment) d. Digital Control Systems e. All Balance of Plant Items. f. Fuel Treatment. g. Water Treatment. h. Occupational Health & Safety in a Thermal Power Plant. Items shown in Section 4.9.2.2. A ~ H, above will also include but not limited to the Start-up, Operation, Shutdown, Troubleshooting, LOTO (Lock Out Tag Out) Procedures, and Preservation of Plant during extended shutdowns. Onshore Training:The Bidder shall conduct a minimum of 90 man weeks at the jobsite providing Plant Operations on-the-job training (6 weeks × 15 MOE Personnel). Of these 90 man weeks, at least 20 percent and no more than 40 percent will be classroom training. The remaining 60 to 80 percent of the training will be conducted in the field. It is preferred that this training be coordinated with significant field activities such as unit oil flush, initial gas fill (if required), initial turbine roll, and initial synchronization. The instruction shall consist of at least the following phases: a. 40 percent of the time will be devoted to discussing the theory of items Section 4.9.2.2. A ~ H above. b. 60 percent of the time will be expended discussing operation of items Section 4.9.2.2. A ~ H above. This will be coordinated with the significant field activities previously identified above. 4.9.2.3 Plant maintenance training Offshore Training:4-29 KHABAT TPP UNITS 1&2 - VOLUME I
The Bidder shall conduct a minimum of 72 man weeks of Offshore Maintenance training for 18 individuals. (4 weeks × 18 MOE Personnel) The training will be conducted at the manufacturing facility during a time when the major components for the Contract are at a stage of construction that would prove beneficial to the trainees. At least 50 percent of the time will be spent with the equipment and at least 25 percent of the time will be expended addressing the theory of maintenance, including preventive maintenance activities. a. Electricity and Thermal Power Plant Generation and Transmission. b. Steam Turbine Generator and Excitation Equipment. c. Oil Fired Boiler Operation and Emissions (including Flue Gas treatment) d. Digital Control Systems e. Balance of Plant Items. f. Fuel Treatment. g. Water Treatment. h. Occupational Health & Safety in a Thermal Power Plant. Items shown in Section 4.9.2.3. A ~ H, above will also include but not limited to Maintaining and Repairing, Troubleshooting, LOTO (Lock Out Tag Out) Procedures, and Preservation of Plant during extended shutdowns. Specific training for each Engineering Discipline shall be included. Onshore Training:The Bidder shall conduct a minimum of 108 man weeks at the jobsite providing Plant Maintenance on-the-job training (6 weeks × 18 MOE Personnel). This training will be a continuation of the Section 4.9.2.3 Offshore Portion items A ~ H, and will consist primarily of field instruction. At least 20 percent but no more than 40 percent of the time will be classroom instruction. The program will be scheduled to take advantage of
significant
phases
of
construction
and/or
testing
activities
such
as
turbine/generator alignment, generator rotor insertion, unit oil flush, piping system hydro testing, steam blowing, main valves restoration, DCS commissioning, etc. Specific training for each Engineering Discipline will be included. Miscellaneous Training Requirements The MOE/KNOC can change the above percentages between classroom and hands-on training for either the sessions at the manufacturer's facility or the sessions at the job site, but not the overall time at each location. 4-30 KHABAT TPP UNITS 1&2 - VOLUME I
The field training overall duration will not be less than 90 days, the program can be integrated. The Offshore Operations Training and Maintenance Training will not be performed simultaneously. If portions of the on job training are to be accomplished entirely by the Bidder's personnel that are performing an activity to satisfy another section of the contract, the Bidder shall identify in detail how this will be accomplished, including how either activity will be performed as effectively. 4.9.3
Breakdown of training plan ITEM
Minimum Man-weeks Offshore Onshore
z Plant Management Training Offshore 4 weeks of plant management training for 10 people. 4 weeks
×
10 people
=
40 man weeks
40
z Plant Operations Training Offshore 4 weeks of Off-shore plant operation training for 15 people. (5 Shifts, 3 people from each shift) 4 weeks
×
15 people
=
60 man weeks
60
Onshore 6 weeks of plant operation on-the-job training for 15 people. 6 weeks
×
15 people
=
90 man weeks
90
z Maintenance Training Offshore 4 weeks of plant maintenance training for 18 people. 4 weeks
×
18 people
=
72 man weeks
72
Onshore 6 weeks of maintenance training for 18 people 6 weeks
×
18 people
=
108 man weeks
108
6 × I&C people 6 × Electrical people 6 × Mechanical people TOTALS:
172
198
4-31 KHABAT TPP UNITS 1&2 - VOLUME I
4.10
Spare Parts and Consumables The Bidder shall provide with its tender a Firm Fixed priced list of Spare Parts using two (2) years of operation after Operational Acceptance in Schedule H1. The list shall be developed on an estimated usage basis and supporting data from existing plants shall be provided to substantiate the spares holding and usage proposed. The priced list shall include a recommended stockholding to cover all initial inventory, planned maintenance and strategic reserves up to and including the first major overhaul. The list shall be developed on an estimated usage basis and supporting data from existing plants shall be provided to substantiate the spares holding and usage proposed. The Bidder shall fill up the form of the Commissioning Consumables in Schedule H2 within the Firm Fixed price form. The Bidder shall provide all the commissioning consumables for two (2) years of operation after Operational Acceptance. In general it shall be understood that all parts, materials, consumables etc, to be consumed or replaced during installation, commissioning, start-up or test run, that are prior to the plant take-over shall be considered as installation material, and shall be included in the price of equipment and Installation work.
4.11
Special Tools and Lifting devices The Bidder shall supply a complete set of any special tools and other equipment necessary for the dismantling, work storage, re-erection and adjustment of any part of the plant within the Fixed Firm price form in Schedule J. Tools shall be provided in new condition, adequately labeled to their use and contained in stout and suitable padlocked boxes. Any special lifting devices/slings required shall be provided and clearly marked by embossed labels which show safe working loads.
Test Certificates shall be
provided where applicable. Suitable lifting equipment shall be provided to facilitate removal and maintenance of plant and equipment.
Lifting devices shall be designed in accordance with the 4-32 KHABAT TPP UNITS 1&2 - VOLUME I
latest editions of the relevant ISO standard or equivalent.
All electrical and
mechanical functions shall be tested before despatch from the manufacturer’s works. Operational and overload tests shall be carried out on site. Suitable lay down areas and methods of retrieving the equipment should be included to support the integrated approach to the crane facilities.
4.12
Warranty Engineer A warranty engineer shall be located on site for [one] year following the date of Operational Acceptance.
The warranty engineer shall have not less than eight
years experience of power plants similar to the Facility and shall act proactively to ensure the best performance and availability of the plant is achieved.
A CV for the
proposed engineer shall be submitted for approval prior to him taking up the appointment. The approval shall not be unreasonably withheld. The Contract shall include for all travelling, accommodation and subsistence costs of the engineer and for his replacement by a similarly experienced engineer during periods of leave or long-term sickness.
The replacement engineer shall be to
approval. Such approval shall not be reasonably withheld. The warranty engineer shall be available on site between 0800 – 1700 hours Saturday to Thursday, and available for callout duty outside of these hours. The warranty engineering shall be responsible for the following throughout the warranty period: a.
Ensuring that the O&M operator is operating and maintaining the entire plant in accordance with the manufacturers’ instructions, and notifying the MOE and the O&M operator of any shortcomings.
b.
Providing technical advice and support to the O&M operator.
c.
Monitoring the performance and availability of the plant.
d.
Assisting with troubleshooting.
e.
Acting as liaison with the Bidder’s head office for the clearance of any defects existing on Takeover or occurring during the warranty period, to ensure that they are cleared promptly.
4-33 KHABAT TPP UNITS 1&2 - VOLUME I
MOE/KNOC will monitor the performance of the warranty engineer.
Should his
performance be unsatisfactory, the Bidder shall provide a replacement engineer to the satisfaction of MOE/KNOC.
4.13
Risk Management Guideline
4.13.1
Introduction Risk Management is a continuous process that identifies, analyzes, mitigates, reports, and tracks risk that have the potential to adversely affect the project. Risk, along with scope, schedule, and cost, is a fundamental element of the construction project that must be actively controlled and managed. Contractor shall use a formal, systematic process for the management of risk. The Risk Management Plan defines the scope and process for the identification, impact evaluation, and management of risks. It is integral part within the overall project management process to achieve scope, schedule and cost results and shall be factored into every project decision at all levels throughout the lifecycle of the project. Additionally, identifying, managing, and exploiting opportunities is equally important. To that end, the Project shall also employ a formal, systematic process for managing opportunities. The following shall be accomplished: a.
A risk management process is developed and implemented that includes: z
Risk
z
Risk Assessment
z
Risk handling strategies for each item including mitigation steps for
Identification
moderate or high risks. z
Analysis of the cost and schedule impacts to implement a mitigation plan versus realizing the risk, including the development of cost and schedule contingency estimates
b.
z
Tracking of risk and residual risk mitigation plan implementation
z
Reporting on risk status, ownership and ranking
Defines organizational responsibilities regarding the management of risk. z
Provides a summary discussion of the risk assessments of the key risks facing the project and the respective mitigation actions, and
z
Delineates the methodology to execute the risk management workflow process.
The Risk management plan facilitates the matching of the primary Work Breakdown 4-34 KHABAT TPP UNITS 1&2 - VOLUME I
Structure (WBS) elements with the established organizational breakdown structure for the purpose of assigning accountability within the risk management workflow process for subsequent risk handling actions. Contractor shall review risks on a monthly basis in responsible department and integrate them twice a year. 4.13.2
Risk Definitions and Concepts Uncertainty in a project is called risk. It is formally defined as an uncertain event or condition that, if it occurs, has a positive or negative effect on a project objective. Risk is an inherent part of all activities, whether the activity is simple and small, or large and complex. The relative size and/or complexity of an activity may or may not be an indicator of the potential degree of risk associated with that activity. There are two main sources of risks to the project.
4.13.2.1 Event Risks Event Risks are potential occurrences that can have an impact on project scope, increase project cost and/or schedule, reduce safety margins, or reduce the quality of the final product. Event Risks can be caused both internally and externally, and, in many cases can be foreseen by project management within some reasonable planning horizon. Examples of a foreseeable event include instabilities in qualified craft labor at a construction site, or the ability of component suppliers to meet their delivery schedules.
Event Risks include the following categories:
Event Risks a. Technical z
Design
z
Safety
z
Environment
z
Technology
z
Interfaces
b. Programmatic All projects are based on a set of assumptions that affect the scope, schedule, and cost of the project.
These assumptions establish the basis for determining the
estimated schedule duration and cost for each activity in the WBS. The expected completion date of the project and the estimated cost-at-completion are predicated on these assumptions holding true. Many of these assumptions address future conditions that shall not be known with certainty until later in the project. Therefore, there is a probability that something may happen to render an assumption false. 4-35 KHABAT TPP UNITS 1&2 - VOLUME I
These are referred to as “Events” Risk, whether having a positive or negative effect on a project, is the product of the probability of the Event occurring multiplied by its impact on the project. There are some Events that are either random or of such a nature that they cannot be influenced (such as natural disasters). Random events such as these usually cannot be effectively managed (i.e., because the probability of such events occurring can not be controlled and their impact usually can not be quantified until “after-thefact”). On the other hand, many Events can be managed (either in terms of proactively influencing their probability of occurrence or minimizing their impact). Since management resources are limited, it is the role of the Risk Management process to identify which of the hundreds of Events that could affect the Project should be proactively managed. 4.13.2.2 Uncertainty Risks Uncertainty Risks are the result of variability of the estimating data used to create the project baseline cost and schedule estimates. A baseline plan is a series of logically linked activities, with duration and cost established through a structured estimating process. All estimates contain uncertainty that can be bounded within predicable ranges based on information available to an estimator, including whether the proposed activity has been performed before. Importantly, through simulation, the effect of schedule and cost variation can be modeled and understood, and, with appropriate feedback, the causes of uncertainty can be managed during the project execution, thus lowering the potential risk impact. Historically, estimating uncertainties have been included in project cost estimates as “traditional contingency.” This primarily covers uncertainties in project cost and schedule estimates that result from: a. Errors and omissions, b. Inflation, c. Adverse weather, d. Pricing variances, e. Quantity variances, f. Complexity, and g. Facility access. 4.13.2.3 Key Definitions Risk and Opportunity Management embrace various concepts, terminology, and elements that are designed to enhance the overall Project Management and 4-36 KHABAT TPP UNITS 1&2 - VOLUME I
Integration process for the project. Some Key Definitions are provided below: a. Consequence of Occurrence A qualitative or quantitative representation of the potential impact of an identified risk materializing. b. Contingency Resources required to increase confidence for project success and effectively manage the risks that are normally considered within the project’s control (i.e., “known unknowns”) c. Event A discrete occurrence that may affect scope, schedule, and/or cost of a project for better or worse.
Internal events are those within the control of the project.
External events are outside the control of the project. d. Event Risk Broad-based issues that can have an impact on project scope, increase project cost and/or schedule, reduce safety margins, or reduce the quality of the final product (examples: labor, contract issues, inability of suppliers to meet delivery schedules, regulation changes, etc.) e. Monte Carlo Analysis An automated probabilistic risk assessment technique used to measure the effects of uncertainty within defined probability distributions. f. Probability of Occurrence A qualitative or quantitative representation of the relative probability of realizing an identified risk. g. Programmatic Risk The impact associated with disruptions created by decisions, events, or actions that have the potential to affect a project’s outcome. h. Qualitative Analysis A subjective assessment of the level of confidence within the defined scope of work. i. Quantitative Analysis An objective assessment of the level of confidence within the defined scope of work. j. Residual Risk Risk elements remaining after the implementation of selected risk handling strategies. k. Risk 4-37 KHABAT TPP UNITS 1&2 - VOLUME I
An uncertain event or condition that, if it occurs, has a negative effect on a project objective or goal.
Risk is always derived quantitatively by obtaining the product
of probability of occurrence and consequence of occurrence. l. Risk Management The act or practice of dealing with risk.
It includes planning for risk, assessing
(identifying and analyzing) risk areas, developing risk handling options, monitoring risks to determine how risks have changed over the course of a project, and documenting the overall risk management program. m. Technical Risk The impact associated with uncertainties regarding the development of a new design, or the use of existing technologies within different applications, either to provide a greater level of performance or to accommodate imposed requirements or constraints. n. Uncertainty Risk Issues directly tied to the project scope, cost, and schedule, and which are the result of the natural variation in events and processes within the project. o. Worse-Case Schedule Impact (Risk Assessment Form) This is defined as the total delay in months associated with the occurrence of a risk event without the benefit of mitigation strategies. p. Worse-Case Cost Impact (Risk Assessment Form) This is defined as the total cost in € associated with the occurrence of a risk event without the benefit of mitigation strategies.
4-38 KHABAT TPP UNITS 1&2 - VOLUME I
4.13.3
Risk Management Process Baseline: (Scope, Schedule & Cost) Assumption Plans
Integration Cost & Schedule Baseline
Action Item List
Planning Identification By WBS Risk Management Plan
Mitigation Strategies Implementation Cost & Schedule Impacts
Risk /O p Ass portun es s m ity ent
Residual Risk Cost & Schedule Impacts (Risk-based Contingency)
Quantification
Handling Event Screening Checklist
Impact Determination
Potential New Risks/Opportunities
Risk/Opportunity Assessment Report
Inputs Outputs Process Function
Risk and Opportunity Management Process Each block represents a step in the functional performance of risk management. All encompassing in this plan is the qualification of risks from on-going identification to final close-out of the risk.
Risk Management is essentially an ongoing and iterative
process, which applies the best efforts of a knowledgeable project staff to a suite of focused and prioritized issues. At the center of the risk management process are the four fundamental steps for risk quantification/assessment needed for effective risk management: a. Risk Identification b. Risk Quantification c. Risk Handling/Mitigation Planning d. Risk Impact Determination 4.13.3.1 Risk Identification Risks may be “project-wide” or be isolated to one or more areas of the project WBS. The development of the preliminary baseline shall identify risks at the total project, subsystem/procurement package and activity levels. Risks may be of many types, including but not limited to: technical (physics, 4-39 KHABAT TPP UNITS 1&2 - VOLUME I
research, or engineering), schedule/time, budget/cost, funding, resource availability, procurement, integration, performance variances, proposed changes, and many other types (e.g., political, economic, etc.), and may be of a source internal or external to the project.
Risks may be at the “project-level” (generally affecting the
entire project) or at any sub-level of the project, which may also be at different project levels. Key sources of input to risk identification are: a. Task descriptions (Scope statements, etc) The nature of the activity shall have a major effect, for example, an activity involving proven technology may have significantly less risk when compared to an activity involving new technology, or highly complicated manufacturing processes, which may require extensive development and thus have a higher risk. b. Other Planning Documents Cost and/or schedule estimates may provide greater risks when developed from early or incomplete information. Procurement arrangements may identify unusual market conditions such as regional sluggishness or lack of multiple suppliers. Finally, the DA may develop hazard lists that identify additional sources of risks. c. Historical information This information can be extracted from previous activity files, other Tokamak projects, and commercial databases.
Lessons learned can also provide input.
d. Assumptions Assumptions identified during the functional and operational requirement development phase of the system engineering process are often good sources for potential risk and should be considered risks until the uncertainties can be resolved. Risk identification shall be initiated by using risk source checklist, process flow charts, interviews with subject matter experts and team brainstorming. In using checklists, the process of identifying different types of risks shall be started. The results of the risk identification phase are clear statements of risk with corresponding bases. The event that creates the risk shall be identified, as well as the effect could have on the project or activity.
This information shall be
documented in a Risk Assessment Form. Meetings shall serve as standing mechanisms for identifying new project risks. Technical and Programmatic – The following occurrences may prompt re-evaluation of project risks, if appropriate: a. Upon significant changes to project scope, including the addition of major scope, 4-40 KHABAT TPP UNITS 1&2 - VOLUME I
b. Upon the reduction or addition of available resources or changes to the funding profile, c. Upon a delay or acceleration of the project schedule, d. Upon significant changes to field conditions, e. Upon the realization that project baseline changes are imminent, f. Upon changes to major procurement cycles, or g. As directed by project senior management. Cost and Schedule – A qualitative analysis shall be performed at the following milestones to assess the level of management confidence with project scope, cost, and schedule: a. Upon completion of Conceptual Design, b. Upon completion of Preliminary Design, and c. Upon completion of Final Design 4.13.3.2 Risk Quantification Risk quantification or assessment involves assessing risks to determine potential project consequences.
This consists of determining the likelihood of the identified
risk actually occurring, assessing the impact if it does occur, and then assigning an overall rating to the risk. The contractor shall collect this information and communicate it with all involved members of the project team. The guidelines for use of the project risk assessment matrix are given below. a. Determining Likelihood Risks shall be categorized by likelihood or probability of occurrence. Generally, a risk that is determined to be in the “Very Likely” to occur category is one that has a probability of 80% or greater of occurrence.
A risk that is “Likely” to occur is
one that has a probability between 40%–80%.
A risk that has less than a 40%
chance of occurring is categorized as “Unlikely”. It should be noted that even risks categorized as “Very Unlikely” or “Not Credible” to occur may still happen. b. Determining Impact Risks can also have varying impacts/consequences on a project. If a risk occurs, a negative consequence usually results. The consequence shall typically adversely affect the technical accomplishment, result in a schedule or milestone slip, and/or cause a cost impact. The degree of the consequence is what is measured in this step. Each risk shall be categorized as follows z
Negligible
z
Marginal
z
Significant 4-41 KHABAT TPP UNITS 1&2 - VOLUME I
z
Critical
z
Crisis
c. Overall Risk Rating A risk’s probability shall be weighed against its potential impact in order to effectively gauge the measure necessary for dealing with that risk. Each risk shall be assigned an overall risk rating as high, moderate or low based on the X and Y axis intersection point of the risk assessment matrix. The management actions to be taken correspond to the overall risk rating. High Risks. Require close monitoring and active on-going involvement of the contractor. These risks also require the identification of a mitigation strategy (recorded on the risk register), and regular review at project management meetings. Frequent high-level visibility of these risks is required. Elimination and/or mitigation of risks rated as “High” overall is a priority. Moderate Risks. Require regular periodic assessment and action by the Contractor., as appropriate to reduce the chance of these risks occurring or escalating. Although not usually of the severity of “High” risks, the risks with an overall categorization of “Medium” can still have, in some cases, a high impact to the project if they occur. “Medium” risks shall also be reviewed at the project status meetings. Low Risks. Risks with an overall categorization of “Low” shall be monitored by the Contractor. d. Risk Assessment Matrix The project employs an established risk methodology for consistency and quality in the risk management process, as represented by the risk assessment matrix shown below. The y-axis determination (Likelihood of occurrence) is first made for an identified risk, followed by the x-Axis (Impact/Consequence). The table then yields an “overall risk rating”. This overall rating is initially reviewed and validated as the “best fit” by the person identifying the risk, and then presented to their Management for their review.
Adjustments may be made based on an initial
“fact finding” period. The risk is then expeditiously entered into the Project Risk Register. Later adjustments in the overall risk rating may be made, up or down, depending on governing events and/or the relative success of applied mitigation strategies. Risk assessment matrix is shown below.
4-42 KHABAT TPP UNITS 1&2 - VOLUME I
Probability of Risk
Very Likely
Moderate
Moderate
High
High
High
Likely
Low
Moderate
High
High
High
Unlikely
Low
Moderate
Moderate
High
High
Very Unlikely
Low
Low
Moderate
Moderate
High
Not Credible
Low
Low
Low
Low
High
Critical
Crisis
Negligible
Marginal
Significant
Consequence 4.13.3.3 Risk Handling and Mitigation Risk handling and/or mitigation is the identification of the course of action or acceptance selected for the purpose of effectively responding to a given risk. There is generally four risk handling strategies for responding to risks: 1.) Avoid, 2.) Transfer, 3.) Mitigate, or 4.) Accept. a. Avoid This strategy focuses on totally eliminating the specific threat or risk-driving event usually by eliminating the potential that the risk event can occur (i.e. – take action to drive the likelihood of occurrence to zero). This can be accomplished through total structure, system, or component redesign, or by selecting an alternate design approach, which does not include the particular risk event, etc. Generally it is not possible to eliminate all risks, but specific risk events can often be eliminated with this strategy. If the strategy is to avoid the risk, the cost and duration to implement this strategy is determined and documented on the Project Risk Register. Once the strategy is implemented, the risk level for the specific element shall be reduced to zero. No residual risk remains with this strategy.
In some cases, substitute activities or
processes may introduce new risk. b. Transfer This strategy is used when an activity scope with identified risks can be transferred to another activity or entity, especially when this risk can be more easily handled within the receiving activity or entity. A risk can be transferred to an outside. This in itself is a risky strategy in that the organization may fail to meet the agreed requirements, or introduce news risks into the organization. In any case, the individual or organization receiving the risk must accept the risk transfer.
4-43 KHABAT TPP UNITS 1&2 - VOLUME I
If the strategy is to Transfer the risk, the cost and duration to implement this strategy is determined and documented. Once the strategy is implemented, the risk level for the specific site shall be reduced to zero. No residual risk remains with this strategy. c. Mitigate This strategy identifies specific steps or actions that shall improve the chances that an activity shall succeed by: z
Reducing the likelihood of the occurrence of the risk event, or
z
Mitigating the consequence of a risk event, or
z
A combination of the two.
The expected outcome of a risk event can be reduced by using proven technology to lower the likelihood that the activity shall be impacted, or by adding specific mitigation actions to the activity scope. Any corresponding cost and schedule implementation impacts due to the mitigating actions must be addressed during impact determination. at a reduced level.
Using this strategy, a risk remains, but
The remaining diminished risk is called residual risk.
The
impacts of these residual risks shall be identified during impact determination. If the strategy is to Mitigate the risk, then the cost and duration to implement this strategy is determined and documented.
Included in the analysis is a
determination of whether to initiate a mitigation plan – depending on the plan cost and schedule opposed to the cost and schedule impact if the risk is realized. In addition, the likelihood, the consequence, and the risk level of the residual risk (i.e. risk after mitigation action) are then determined. The potential cost and schedule impacts of the residual risk are identified using three data points, namely the best case (or most optimistic), the most likely, and the worst case (or most pessimistic). These are used in a triangular distribution to assess the cost and/or schedule uncertainty brought on by the risk element. d. Accept Accepting a risk is essentially a “no action” strategy. Selection of this strategy is based upon the decision that it is more cost or schedule effective to continue the activity as planned with no resources specifically dedicated to addressing this risk. However, the “no action” strategy may be hedged by developing a contingency plan in case the risk event occurs and then tracking the risk to assure that it does not increase during contingency execution. In this case, the contingency plan does not mitigate the consequence, but seeks to control the impacts that typically result from the event consequence. Low risks are typically accepted. However, 4-44 KHABAT TPP UNITS 1&2 - VOLUME I
even though Low risks may be accepted, one must not overlook the cumulative impact to an activity resulting from a multitude of Low risks, especially if those risks are concentrated in one specific activity area. For a handling strategy of Accept, the residual risk equals the initial risk because this strategy does not change the risk level.
If the risk is accepted, without
additional actions, then the cost and duration of this handling strategy implementation is zero, which is documented on the Project Risk Register. 4.13.4
Integration with Project Management Once the risk handling strategy has been selected, it shall be reviewed by the responsible management and approved and integrated into the project planning. The Contractor shall collect and communicate the risks to all involved members of the project team. For risks that are designated as intra-site risks, the risk handling strategy must be integrated in the specific procurement arrangement. For risks that are inter-site or project-level, the risk handling strategies shall be revied and approved by project manager. Once approved, the risk handling strategy activities, cost, and schedule impacts must be integrated into the baseline plan.
4.13.4.1 Risk and Baseline Change Control Relationship Changes to the Project scope, schedule and cost shall be managed through a formal change management process. All proposed internal and external changes shall be formally evaluated for their impact and risk to the project, as part of the approval process. Proposed baseline changes may be merited to mitigate risk(s). Correspondingly, The Contractor shall evaluate proposed changes to fully understand the potential risk consequence, either positive or negative. Externally directed changes shall also be evaluated for risk consequence. Any risk emanating from proposed or authorized project baseline changes shall be managed through the Project risk management process. 4.13.5
Risk Closure Closure of a risk is dependent on closure of the actions necessary to implement the chosen strategy.
It begins by closing out the action item(s) and accompanying
schedule item(s). Once all the actions posted against the risk mitigation strategy(s) are completed, the risk can be closed.
Once closed the Project Risk Register
should be updated, sent to related parties and then archived. 4.13.6
Opportunity Management Process 4-45 KHABAT TPP UNITS 1&2 - VOLUME I
The Contractor shall establish an opportunity management process similar to the risk management process.
Opportunity management is to identify elements that
may enhance or provide benefit to the project cost, schedule and/or technical performance. The opportunity element identification process shall be assessed simultaneously with the risk element identification. 4.13.6.1 Opportunity Handling Strategies Opportunity handling is the identification of the course of action or acceptance selected for the purpose of effectively responding to a given element.
There are
generally four opportunity handling strategies for responding to opportunities: 1.) Exploit, 2.) Share, 3.) Enhance, or 4.) Ignore. a. Exploit This strategy may be selected for Events with positive impacts where the organization wishes to ensure that the opportunity is realized. This strategy seeks to eliminate the uncertainty associated with a particular upside Event by making the opportunity definitely happen.
Directly exploiting responses includes
assigning more talented resources to the project to reduce the time to completion or to provide better quality than originally planned. b. Share Sharing a positive Event involves allocating ownership to a third party who is best able to capture the opportunity for the benefit of the project.
Examples of
sharing actions include forming risk-sharing partnerships, teams, special-purpose companies, or joint ventures, which can be established with the express purpose of managing opportunities. c. Enhance This strategy modifies the “size” of an opportunity by increasing probability and/or positive impact Events.
Seeking to facilitate or strengthen the cause of the
opportunity, and proactively targeting and reinforcing its trigger conditions, might increase probability.
Impact drivers can also be targeted, seeking to increase
the project’s susceptibility to the opportunity. d. Ignore This is to document that the opportunity was considered, but not implemented. Reasons for not implementing an opportunity may be due excessive implementation cost and/or schedule increase, compared to the return from this element.
4-46 KHABAT TPP UNITS 1&2 - VOLUME I
5
SITE DETAILS AND SAFETY REQUIREMENTS
5.1
Location of Site, Access and Use of Site The site conditions are given in Volume 2, Schedule A and drawings showing the location of the site are included in Volume 3. The Bidder shall inform himself fully as to all transport facilities, requirements and loading gauges to ensure that all equipment as packed for transport shall conform to these limitations, and shall be responsible for all damage to roads, bridges, etc., during transportation. The location of the laydown parking and construction areas will be the responsibility of the Bidder. The Bidder shall provide his own hardstanding storage, working areas, access ways, any roofed accommodation and security arrangements where necessary. Such facilities shall be removed from site on completion of the Contract after the agreement of the KNOC. The Bidder shall, and at his expense, take precautions to keep all existing and new temporary and permanent roadways clear of any spillage from his traffic. All such spillage, which occurs, shall be cleared immediately, including excessive earth or other materials brought in on wheels or tracks of the traffic. The Bidder shall confine his labor, material, plant and equipment to within the designated areas of which he has been given possession. No lands or other places which are the property of the MOE shall be used except in accordance with the instructions of the MOE. The Bidder shall at any time move any vehicle, temporary work, plant or other obstruction within his control that may be required to be moved by the KNOC and the Bidder shall move any such vehicle, temporary work, plant or obstruction promptly on the instruction given by the KNOC, all at the Bidder’s own cost. The Bidder shall maintain access for the inspection, operation and maintenance of any of the KNOC’s premises, plant or works which are within the contract site boundaries. 5-1 KHABAT TPP UNITS 1&2 - VOLUME I
The Bidder shall maintain the whole of his operations in a clean, tidy and safe condition and shall arrange his materials in an orderly manner. All rubbish, waste materials, debris and the like shall be regularly and systematically cleaned off the working areas as it accumulates and deposited in collecting points from which the Bidder shall regularly dispose of waste materials. The Bidder shall ensure that the site and adjoining lands belonging to third parties are kept free from construction materials of any kind arising from the works and that no damage occurs to third party property. On sites which are in use, or have been in use, or sites in which services may cross, the position of any existing services in or near the proposed work area shall be pinpointed as accurately as possible by means of site plans. The Bidder shall use locating devices to confirm the position of the services. Any pipe or cable which is uncovered shall be treated as live unless proven otherwise. Upon completion of the work in a particular area, any warning tiles or tapes shall be replaced.
5.2
Site Facilities The Bidder shall provide portable office site accommodation for his own and sub Bidders staff, which shall conform to the requirements of any local and statutory authorities, for the area in which the work is situated. Site accommodation and arrangements shall be subject to the approval of the KNOC in all respects. The Bidder shall establish and operate a site security system, all staff employed at site will be issued with security passes by the Bidder to permit access to and from the site. It shall be the Bidder's senior representative’s responsibility to ensure that security rules are complied with. No vehicles will be allowed on site except those carrying materials, or necessary for construction. 5-2 KHABAT TPP UNITS 1&2 - VOLUME I
The Bidder shall ensure that at least one person amongst the site staff during site working hours is trained in first aid and a first aid facility shall be maintained with basic needs. Medical centre shall be provided with all accessories included. The Bidder shall supply, maintain and service for the duration of the contract, site office accommodation for the KNOC/MOE’s construction management personnel. This accommodation shall be separate from but adjacent to the Bidder’s own offices and other facilities. It shall comprise of a number of offices and include toilet and kitchen facilities. The offices shall be suitably furnished with desks, chairs, benches and lockable filing cabinets. The offices shall be installed with full office facilities, such as lighting and small power, telephone lines, water supply and drainage. The Bidder shall supply graded parking areas for KNOC’s vehicles. Canteen facilities shall be provided by the Bidder during the construction phase. On commencement on site the Bidder shall insure the KNOC/MOE’s offices and contents against fire, and other risks ordinarily insured against. Before the erection of any temporary huts, sheds or other buildings which the Bidder may require for his own purposes, the Bidder shall obtain approval from the KNOC for the size, type, location and drainage arrangements. Notice shall also be given to the KNOC of any intention to dismantle any hut or remove the same from site. After completion of erection of the office(s) and other temporary accommodation, the Bidder shall arrange an inspection, to be attended by the KNOC and the local fire authority. The Bidder shall comply with all recommendations made by local fire authority. Any costs involved in making the buildings comply with the fire officer’s requirements shall be deemed to be included in the contract price.
5-3 KHABAT TPP UNITS 1&2 - VOLUME I
The Bidder shall provide sanitary conveniences for the use of workmen employed on the works and in such a manner and number as shall conform to the statutory or other appropriate regulations and the whole shall be installed to the satisfaction of the KNOC. The conveniences shall be located centrally to the works and shall be to a high industrial standard, heated/ventilated (as necessary) and maintained in clean, hygienic and in good working order at all times. The Bidder shall include for removal of all temporary offices, welfare facilities, sheds and other temporary buildings at the completion of the works and restore the site to a state, to the satisfaction of the KNOC.
5.3
Site Services During Construction Period The Bidder shall be responsible for the provision of all site temporary or construction services. Refer also to the Civil Works section.
5.3.1
Site construction electricity supplies The KNOC shall make arrangements for the site construction electricity required for the construction of the works. The cost of infrastructure necessary to provide necessary connections shall be the responsibility of the Bidder. The Bidder shall provide suitable generation as a backup to KNOC supplies. KNOC accepts no responsibility for loss of supply to the site during the construction and commissioning periods. The KNOC cannot guarantee the availability and/or reliability of any supply identified as existing at the site. All cables installed for temporary electrical supplies shall be routed so that they are clear of building operations or constructional work, shall not impede access and egress, and shall be at least 150mm clear of steam, gas and water pipelines. Lampholders and other accessories shall not be suspended from electric cables. Cables passing under roadways and access ways for transport and mobile plant shall be laid in ducts at a depth of 600 mm. A cable marker shall be 5-4 KHABAT TPP UNITS 1&2 - VOLUME I
installed at each end of the road crossing. Records and drawings of the temporary distribution system and cable routes shall be kept up to date. As soon as any parts or whole of the Bidders installation is no longer required for carrying out the Contract Works, the Bidder shall disconnect and remove the same to the satisfaction of the KNOC.
5.3.2
Water supplies The Bidder shall be responsible for making his own arrangements for any water supplies required during the construction of the plant, including any metering apparatus and the payment of any charges.
5.3.3
Other services The Bidder shall also provide at least the following and others if required: a.
at laydown areas and at work faces temporary fencing, lighting and guarding and all other materials and services necessary for the safety and security of persons and property;
b.
temporary roads, parking areas etc;
c.
telephones
d.
fire-fighting equipment;
e.
waste disposal facilities;
f.
sanitary facilities;
g.
all necessary temporary equipment for construction, commissioning and testing; until project completion has occurred.
The Bidder shall include for the removal and disposal off-site of all ground works associated with the temporary services, including the removal of temporary sewage works, the safe demolition and infill of manholes, chambers etc, and the safe termination and/or blanking off from permanent services under the control of the KNOC and/or other public or private bodies, to the satisfaction of the KNOC.
5-5 KHABAT TPP UNITS 1&2 - VOLUME I
5.4
Health and safety at work The KNOC will monitor the Health and Safety practices of the Bidder against the agreed H&S Plan which shall be prepared and developed by the Bidder and be subsequently approved by the KNOC. Within 30days of contract award, but before construction work begins, the plan shall be prepared and passed to the KNOC for comment/approval and the Bidder shall ensure that it is regularly and properly adjusted to accord with the Bidders involved and to site activities. The Bidder must incorporate into this plan comprehensive method statements for all major construction activities and provide copies of these to the KNOC. The method statements will include, but not be limited to, working methods, plant utilization, construction sequence and safety arrangements. The KNOC will authorize construction activities to start only when advised by the Bidder that there is a sufficiently detailed execution stage of the Health and Safety Plan in place. The Bidder shall provide a full time safety officer at site all times-the incumbent should be appropriately qualified for this role. The Bidder is fully responsible for site safety. The Bidder shall make allowance within his program for carrying out his duties in the above respects. The Bidder shall prepare comprehensive method statements for all interface construction activities and submit these to the KNOC for review at least thirty (30) days prior to the commencement of the relevant activity. The method statements will include, but not be limited to, working methods, plant utilization,
construction
sequence
and
safety
arrangements,
permit
requirements etc.
5.4.1
Risk assessment It will be the responsibility of the Bidder to provide both their generic and site 5-6 KHABAT TPP UNITS 1&2 - VOLUME I
specific risk assessments related to undertaking any hazardous work and/or use of any hazardous materials, and major HAZID and HAZOP studies as required to demonstrate the safety of the proposed design and operation of the plant, or as required under statutory legislation. The Bidder shall ensure that risk assessments on the design elements of the plant are carried out, and the relevant information is included in the construction phase Health and Safety Plan.
5.4.2
Specific risks produced by Bidder activities The detailed Health and Safety Plan to be developed by the Bidder shall include method statements for all high-risk activities to be engaged upon by the Bidder and Sub-Bidders. Work will not be allowed to start on site until method statements have been submitted and accepted by the KNOC. High risk activities that have been identified for the construction works include, but are not limited to:a.
Work on fuel gas and gas oil systems
b.
Chemical handling
c.
Working on and adjacent to water
d.
Diving operations/working under water
e.
Steel fabrication and erection
f.
Scaffolding
g.
Heavy crane lifts
h.
Working at height
i.
Hot work
j.
Large plant handling and installation
k.
Noise
l.
Working with HV, MV and LV systems
m. Excavations n.
Construction of foundations
o.
Contamination
p.
Working in confined spaces
q.
Working adjacent to highways
r.
Tunnelling operations
s.
Tie-ins to existing systems 5-7 KHABAT TPP UNITS 1&2 - VOLUME I
t.
Working adjacent to overhead cables/power lines
u.
Radiographic testing of welds
v.
Operation of plant.
On-site works must be fully co-ordinated by the Bidder. The Bidder should make due allowance for regular co-ordination meetings between all subBidders actively working or about to start working on the site. The Bidder, KNOC and representatives of the KNOC will attend the meetings.
5.4.3
Documents The Bidder shall provide the following documents: a.
The Statement of Safety Policy and Organization with Charts and Appendices.
b.
The Health and Safety at Work Manual.
c.
The Statement of Local Arrangements for Health and Safety, including:i.
any Safe System of Working,
ii.
any Permit to Enter system, and
iii. any Permit to Work System. iv. 5.4.4
Bidder's safe systems of working Prior to commissioning on Site, the Bidder shall establish a Safety and Permit-to-Work system for the Site to ensure that plant is put into and taken out of service in a safe and controlled manner, that the integrity of any adjacent operational plant is maintained and any adjacent construction work can be undertaken in a safe manner. The system shall incorporate where applicable any Permit-to-Work system employed by the KNOC. Where any part of the Works is not covered by the Bidder's Safety Policy or is a High Risk activity (as described below) the Bidder shall submit to the KNOC a method statement covering such part of the Works. He shall immediately submit to the KNOC any subsequent additions to or amendments of his method statement. No work covered by any method statement shall be commenced unless the KNOC has approved the method 5-8 KHABAT TPP UNITS 1&2 - VOLUME I
statement. High risk activities include the following: a.
Steel erection/heavy crane lifts
b.
Hot work
c.
Entry into confined spaces
d.
Use of explosives
e.
Roof work
f.
Excavation work
g.
Degassing vessels/systems
h.
Working at height
The Bidder's Safe Systems of Working as described in his method statements shall: a.
be not inferior to the KNOC's Safe Systems of Working for any part of the Site where both will apply;
b.
incorporate where applicable any Permit to Enter or Permit to Work system employed by the KNOC;
c.
incorporate where applicable any of the documents listed above or any leaflet or card associated with them;
For the purposes of this Clause, references to the KNOC or his employees shall be deemed to be references to any other party present or likely to be present on the Site at the same time as the Bidder.
5.4.5
Training The Bidder shall provide or arrange appropriate training for his employees or any other persons carrying out, or put at risk by, his operations. Such training shall include written instructions incorporating the relevant portions of the Bidder's Safe Systems of Working. Where training is required relating to the KNOC's operations, the KNOC will if so requested provide such training. In this event, the KNOC shall have the right to be paid by the Bidder or the party given training the reasonable cost 5-9 KHABAT TPP UNITS 1&2 - VOLUME I
thereof.
5.4.6
Safety equipment The Bidder shall provide all safety equipment for use on the Works; particularly for above ground and confined space working.
Where such
equipment is subject to statutory inspections, the KNOC shall be provided with copies of the inspection reports. When there is a risk of drowning the Bidder shall provide lifebelts and ensure that personnel wear adequate buoyancy equipment or harness and safety lines, especially full body harness when working above 2m, and ensure that rescue personnel are present when work is proceeding.
5.4.7
Assistance to KNOC When the Bidder is required under the Contract to provide manual assistance to the KNOC or his staff, the Bidder shall ensure that the person or persons so provided are aware of the dangers or hazards which may be encountered on the Site.
5.4.8
Confined spaces Where any part of the Works is to be carried out in a confined space the Bidder shall:a.
Display at the entrance to each confined space a sign warning of the need for oxygen and gas levels to be monitored before access and while work is proceeding.
b.
Provide every person entering the confined space with appropriate training in the use of atmosphere testing equipment, the use of respiratory protective equipment, elementary first-aid and rescue techniques.
c.
Provide fully equipped standy personnel for rescue purposes while persons are working in the confined space.
d.
Monitor the atmosphere in the confined space for oxygen depletion and dangerous gases before any person enters it.
5-10 KHABAT TPP UNITS 1&2 - VOLUME I
e.
Provide every person entering the confined space with breathing apparatus, which shall be suitable for use while working or for emergency use only, depending on the degree of ventilation.
f.
If sufficient means of natural ventilation cannot be guaranteed to provide at all times an adequate circulation of uncontaminated air, provide forced air ventilation even if regular/routine oxygen or other gas levels are shown to be safe.
g.
Ensure that all persons within the confined space vacate it as soon as any alarm sounds, without waiting to record the gas level.
h.
Provide appropriate harness, safety ropes and rescue facilities and if practicable two means of access top to bottom.
i.
Provide when work is in progress radio or telephone communication, or safe visual and oral communication where this is appropriate and background noise levels permit.
j.
Ensure that all electrical tools and equipment are of the appropriate types.
When access to a confined space is expected to be prolonged, for example during the construction of a tunnel, the Bidder shall augment the above procedures by installing continuously reading and recording oxygen and gas monitors within the entrance to the confined space and at the place of working. Such monitors shall operate for 24 hours per day, seven days per week, for the whole period of access to the confined space. The Bidder shall provide copies of the recordings to the KNOC at weekly intervals. The Bidder shall include for training of the KNOC’s resident staff in confined space techniques.
5.4.9
Land owned by third parties The Bidder shall take care when working on land owned by third parties to safeguard the KNOCs or occupiers of such land.
5.4.10
Temporary electricity supply Where the Bidder obtains any temporary electricity supply from a switchboard or other source in the MOE's control, he shall submit to the KNOC and MOE a copy of a certificate of testing and compliance with IEC 60364 before connection to the MOE's source is made, and again at the 5-11 KHABAT TPP UNITS 1&2 - VOLUME I
intervals for re-testing required by the Standard. If at any time the KNOC and MOE does not hold a current certificate, the MOE will disconnect the Bidder's supply.
5.4.11
Fire precautions The Bidder shall take all necessary precaution to prevent fire. Where new risks are introduced in the Works during the construction period, the Bidder shall provide appliances suitable for such risks. When working in potentially explosive atmospheres the Bidder shall employ approved non-electric tools and apparatus suitable for use in such areas.
5.4.12
Compressed gases The Bidder shall make adequate arrangements for the safe storage (including appropriate warning notices) and handling of all compressed industrial gases.
5.4.13
Access, fencing and safety barriers The Bidder shall give notice to the KNOC's operating staff whenever he proposes to start any work which may impede the safe passage of persons and vehicles in an emergency. The Bidder shall provide appropriate safety barriers with hazard warning signs attached around all exposed openings and excavations when the work is in progress. Permanent or approved temporary covers to openings shall be replaced at all other times.
5-12 KHABAT TPP UNITS 1&2 - VOLUME I
5.4.14
Site rules
5.4.14.1 Statutory and other regulations The Bidder shall comply with all Iraq National Acts and Statutory or other regulations. If the law is broken or regulations disregarded, the KNOC may exercise his right to refuse to allow the offenders to remain on Site and will not be responsible for any cost penalty arising therefrom. In the event of the Bidder employing subBidders, it must be clearly understood that it is the responsibility of the Bidder to ensure that the subBidders understand and comply with all regulations in every respect. 5.4.14.2 Safety helmets and safety footwear The Bidder shall provide all safety equipment for use on the Project and ensure adequate training in the use thereof. The safety equipment provided shall be in accordance with internationally recognized standards for this location and weather conditions. Where such equipment is subject to Statutory Inspections, the KNOC shall be provided with copies of the inspection reports. Personal protective clothing which will provide adequate protection for workers such as high visibility jackets, safety helmets, safety footwear shall be worn at all times and shall be provided by the Bidder. Adequate arrangements shall be made for regular cleaning of the protective clothing. Non-slip or studded boots should always be worn because of the risk of slipping on greasy surfaces. All studs should be non-sparking. 5.4.14.3 Protection of hearing Where sound levels cannot be reduced at source, the provision of suitable hearing protection is required when noise levels indicate an equivalent level (Leq) of more than 85 dB(A). When hearing protection is used arrangements should be made to ensure the wearers can be warned of other hazards. 5.4.14.4 Eye protection
5-13 KHABAT TPP UNITS 1&2 - VOLUME I
The following are engineering jobs which always require eye protection by persons doing or closely observing the work: a.
The grinding of metal, stone, concrete or similar materials by a mechanically powered wheel or disc.
b.
Breaking, cutting, dressing or carving of stone, concrete, slag or similar materials by a powered or non-powered tool.
c.
Chipping or scaling of painted or corroded metal surfaces or wire brushing of such surfaces by mechanical power.
d.
Cutting out or cutting off of cold rivets or bolts.
e.
Welding
5.4.14.5 Respiratory protective equipment Where there is a risk to persons at work from a dangerous atmosphere, appropriate breathing apparatus must always be readily available for use and all persons concerned must have received adequate training in the working principles and use of this equipment. Breathing apparatus may need to be used in both routine operations and emergency situations. It is important that the correct equipment is selected for the particular environment for which the user requires protection and that approved procedures are followed in the general care, use and maintenance of such equipment. 5.4.15
First aid and medical facilities The Bidder shall be responsible for the provision of first aid facilities at Site, for the use of his own workforce and that of his subBidders. The Bidder shall also be responsible for the contingency planning for emergency services in the event of incidents, accidents or other emergencies at Site. Medical facilities will not be provided by the KNOC and the Bidder shall be required to make his own arrangements for these services as may be required for his expatriate or locally engaged staff.
5.4.16
Emergency evacuation of the site The Bidder will establish a Procedure for the evacuation of the Site in the event of fire, bomb warning or other emergencies. The Bidder shall provide any adequate checking system to ensure that all his employees and site 5-14 KHABAT TPP UNITS 1&2 - VOLUME I
visitors are removed from the Site in the event of such emergencies. The Procedure will include arrangements for practice evacuation as necessary and twice a year evacuation drills and shall be agreed with KNOC. 5.4.17
Safety management The Bidder shall formally appoint a suitably qualified member of his staff to be responsible for safety aspects of the work on Site and shall ensure compliance with all safety matters of the appropriate local legislation.
5.4.18
Cranes, hoists, lifting equipment and scaffolds, etc All lifting appliances (cranes, pulley blocks, gin wheels, etc) hoists and lifting gear (chain slings, rope slings, etc) must be tested and inspected in strict conformity with the requirements of Schedule G. Records and certificates must be available for inspection at any time. The Bidder is responsible to see that hired cranes comply with the regulations and current certificates are available for inspection. All overhead scaffolds and suspended loads must be properly secured. Approach ladders must be removed or made unscalable whenever the Site is left unattended. Scaffold boards and/or cat ladders must be used when working on roofs. Aluminium alloy scaffolding may not be used. Kick plates shall be provided on all scaffold boards
5.4.19
Electrical safety conditions All work on the site shall be carried out in compliance with the relevant Iraq National and local Construction Regulations.
5.4.19.1 Portable and transportable equipment All portable hand-tools and equipment should operate on 50 volt ac supply unless specified otherwise. Under certain circumstances, tools and equipment for use on 110 volt ac supply may be used, but only if written permission is given by the KNOC, who will first ensure that the earthing arrangements are satisfactory. If only 240 volt ac or 400 volt ac equipment is available special dispensation must be obtained, in writing, from the KNOC. Dispensation will only be given 5-15 KHABAT TPP UNITS 1&2 - VOLUME I
if a monitored earth leakage unit is fitted. Portable lighting shall operate at not more than 110 volt ac single-phase. All electrical equipment must be in safe working condition to the satisfaction of the KNOC. Should equipment be found to be faulty it must be made good by the Bidder at his own expense or otherwise replaced. 5.4.19.2 Supplies The Bidder shall be responsible for obtaining any electrical supplies required to carry out his contract works including all that is necessary to provide a safe and satisfactory supply and distribution system. 5.4.19.3 Bidder's wiring The Bidder's distribution, lighting systems and hut wiring shall be in accordance with Internationally acceptable standards for the distribution of electricity on construction and building sites. 5.4.19.4 Lighting It is the responsibility of Bidder to provide adequate lighting in every work place. The lighting system shall be such that nuisance to local residents shall not be caused.
5-16 KHABAT TPP UNITS 1&2 - VOLUME I
6.1
Steam Generators and Auxiliaries
6.1.1
Boiler proper and accessories
6.1.1.1 Design and construction A. General The boilers shall be designed throughout so as to insure continuous, safe and economical operation providing the maximum of reliability and without undue heating, vibration or noise. The boilers and its auxiliaries shall be in slide along arrangement. A proven furnace design shall be chosen such that flow stability is assured during startup and under constant pressure operation as specified. Complete Boiler, pressure vessel, and piping shall be designed and installed in accordance with ASME Boiler, Vessel, and Piping Codes. B. Heat Transfer Surface 1) The furnace shall be structurally designed with no permanent deformation to the furnace enclosure for transient draft pressure conditions of at least ±900 mmH20. The draft-side design pressure shall be of sufficient magnitude to accommodate this transient condition. In addition to design the unit for the above transient pressure conditions, the Bidder shall describe what additional provisions, if any, will be incorporated to accommodate or prevent boiler explosions/implosions. If additional controls are required, these shall be furnished as a part of the boiler control system and burner fuel control systems. 2) The Bidder shall show that furnace, drum, superheater, reheater, economizer as well as the other sections or components of the steam generator are designed with liberal margin in regard to water-cooled or water and steam cooled heat absorbing area, tube sizing and spacing, 6.1-1 KHABAT TPP UNITS 1&2 - VOLUME I
combustion gas velocities entering and through the superheater and reheater sections, and any other factors which affect such design in order that tube corrosion and erosion are minimized and unit availability will be as high as possible. 3) The flue gas temperature at entry to the first convection section shall not effect on tube materials at any load. 4) The Bidder shall show that the average and peak heat absorption or volume heat release rates in the furnace, particularly at or near the burner zone are minimized with resulting minimum waterwall tube metal temperatures. 5) Projected area heat release rate(EPRS heat release rate) shall not exceed 420,000 kcal per square meter per hour. Volume heat release rate shall not exceed 240,000 kcal/m3.h for two(2) pass type and one(1) pass or box type boiler. The Bidder shall specify maximum burner input for oil in his proposal data sheets. 6) The following definition shall be used to calculate the heat release rates. a) The first convection section means the first superheater or reheater section having a clear transverse spacing less than 380 mm. b) Effective Projected Radiant Surface (EPRS) of one pass or box type boiler shall be taken as the total projected area of the planes which pass through the centers of all furnace wall tubes, plus the area of the plane perpendicular to the gas flow at the location where the furnace gases reach the first convection section. EPRS of two pass type boiler shall be taken as the total projected area of the planes defined by furnace volume. In calculating the EPRS, the surfaces of both sides of the superheater and reheater platens extending into the furnace, 6.1-2 KHABAT TPP UNITS 1&2 - VOLUME I
provided that a clear transverse spacing is great than 380 mm for two pass boiler and to first convection section for one pass or box type boiler shall be included. c) Furnace volume of two pass boiler shall be that of the furnace space enclosed by the planes which pass through the centers of all furnace wall tubes and the imaginary vertical plane perpendicular to flue gas stream just above furnace nose apex or straight along with the rear wall tube center lines at lateral pass inlet in case of no furnace nose apex. Furnace volume of one pass or box type boiler shall be that of the furnace space enclosed by planes which pass through the centers of all furnace wall tubes and the first row of the heating surface just above the furnace. d) Projected area heat release rate is equal to the total heat in the fuel actually burned, plus the heat in the preheated air above 30 degree C, minus the sum of radiation losses, heat in unburned combustibles, latent heat of the moisture in the fuel and from the oxidation of hydrogen in the fuel, divided by the EPRS and expressed in kilocalorie per square meter per hour. e) Volume heat release rate is equal to heat input based on higher heating value from fuel only divided by the furnace volume and expressed in kilocalorie per cubic meter per hour. f)
Furnace plan heat release rate is based on heat input based on higher heating value from fuel only at horizontal cross section plane of the furnace through the burner zone and expressed in kilocalorie per square meter per hour. The area of the plane shall be calculated from the horizontal depth and width of the furnace taken from the center line of the tubes. Burner zone surface is calculated as the circumference of the combustion chamber at the level of the upper burner row times height of burner belt, i.e. center line of lowest burner up to center line
6.1-3 KHABAT TPP UNITS 1&2 - VOLUME I
of upper burner plus half of the distance of the two(2) lowest as well as the two(2) highest burner rows. 7) The Bidder shall provide steam generator heat balance diagrams at BMCR, indicating the following data for furnace, each tube bank and air preheater; a) Furnace heat input by fuel (Qf), kcal/h b) Furnace heat input by air (Qa), kcal/h c) Furnace heat input by gas recirculation (Qg), kcal/h d) Gas temperature at first convection section (Tg),
degree C.
e) Heat absorption (Qb), kcal/h f) Heat of furnace radiation (Qr), kcal/h g) Heat of convection, (Qc), kcal/h h) Heat transfer coefficient (K), kcal/m2.h.K i) Steam or water flow (W), kg/h j) Gas flow (Wg), kg/h k) Air flow (Wa), kg/h l) Heating surface (HS),m2 m) Steam or water inlet temperature (T1), degree C. n) Steam or water outlet temperature (T0), degree C. o) Gas temperature (Tg), degree C. p) Air temperature (Ta), degree C. q) Boiler heat losses by gas (Qg), kcal/h 8) The Bidder shall provide steam generator material diagrams with his proposal, indicating the following data for each tube row of superheater, reheater and economizer, and each tube section of furnace; a) Material
6.1-4 KHABAT TPP UNITS 1&2 - VOLUME I
b) Tube outside diameter (Do), mm c) Tube thickness (Ts), mm d) Design pressure (P), kg/cm2 g e) Calculated maximum gas temperature (Tg), degree C. f) Fluid temperature from entering to leaving each tube row or section (T), degree C. g) Calculated mean metal temperature (Tm), degree C. h) Calculated maximum metal temperature (To), degree C. i) Allowable metal temperature (Tx), degree C. j) Tube length (L), mm k) Welding location, due to material thickness change or material change. l) Tube side spacing and back spacing (L∥, L⊥), mm m) Header design temperatures, design pressure, material, and inside diameter and thickness dimensions. C. Shop Fabrication 1) All stubs which are furnished on headers for tube connections or tubes which are joined directly to the headers shall be strength welded to the headers in the shop, and the headers shall be stress relieved after the stubs or tubes have been welded on. The stubs on the headers shall have end preparation for welding to the tubes in accordance with ASME Section I or equivalent codes. 2) Tube ends that are not shop attached to headers shall be prepared ready for welding in the field. 3) Steam generator shall be designed to avoid tube damage by soot blowing. 4) Shop fabrication of tube and header assemblies shall be made to the maximum degree practicable. Superheater tubes, reheater tubes and 6.1-5 KHABAT TPP UNITS 1&2 - VOLUME I
economizer tubes should be shop assembled into modules of two or more elements along with stringer tube supports and element spacers. The Bidder shall state dimensions and weight of largest and/or heaviest assembly to be shipped. 5) Steam generator tubes and headers will be acid cleaned by KNOC after the erection of each steam generator.
Before shipment, these
tubes shall be cleaned by the Bidder of all foreign material, including loose dirt, mill scale, oil, etc. by blowing with compressed air, sponging or mechanical means as required and sealed with securely attached caps. The Bidder shall furnish an adequate number of connections at suitable locations for acid cleaning and a detailed procedure for acid cleaning shall be approved by KNOC. 6) Minus tolerance shall not be allowed for the thickness of tubes, header stubs and headers of furnace water wall, superheater, reheater and economizer. E. Boiler Vibrations The steam generator shall operate free of objectionable vibration under all conditions of operation associated with service in a central power generating station.
If the steam generator shows, in the opinion of KNOC ,
evidence of excessive or objectionable vibration, the Bidder, at his own expense, shall promptly eliminate such vibration to the satisfaction of KNOC . The Bidder shall submit calculations and other data to show that his design prevents vibrations. 6.1.1.2 Furnace A. Furnace walls shall be suitably arranged for the type of steam generator. B. Tubes shall be seamless and all connections shall be welded. Backing rings shall not be permitted in all tube weld joints of the water-cooled furnace. 6.1-6 KHABAT TPP UNITS 1&2 - VOLUME I
The water wall tube of the lower furnace (chamber) shall be considered to prevent departure nucleate boiling. Tube spacing and arrangement shall permit the removal and replacement of any tube without removing others. C. Headers shall be provided with necessary inspection holes with seal welded cover plates. D. The Bidder shall state method of obtaining balanced water flow through the boiler water wall panels, and means of protecting such circuits from blockage by scale or foreign matter in the water. E. The Bidder shall provide water wall tube temperatures measurements for control and monitoring. The Bidder shall indicate the maximum allowable difference of wall temperature between two adjacent furnace wall tubes. F. The forged or welded ‘Y' pattern pieces such as bifurcate tube, trifurcate tube, etc.
are not acceptable, except the use of inverted ‘Y’ pattern piece.
G. The number and location of access doors in the upper furnace shall be submitted for KNOC approval. H. A gas tight welded fin-tube-fin furnace wall construction shall be supplied. The construction can be with either extruded finned tubing with bars welded between plain tubes, or with fusion welded fins. The fin end shape between tube and tube shall be round trimmed for thermal stress reduction. Maximum furnace wall tube thickness in high flux (lower furnace) zones shall be less than 7 mm including corrosion allowance of not less than 1.0 mm. The Bidder shall specifically describe any areas where welded fin-tube-fin wall construction will not be used.
6.1-7 KHABAT TPP UNITS 1&2 - VOLUME I
I. Rear wall shall be accessible from the bottom elevation of furnace to an elevation above the nose cone for installation, operation, and maintenance of sootblowers, instrumentation, and other accessories. J. Hopper bottom shall be entirely water cooled with two sides inclined at least 30 degree C from the horizontal. K. Furnace tube arrangement shall be described in detail giving full constructional details, including tube attachments and the methods of support of the furnace walls. L. The Bidder shall state the structural fatigue limits of the furnace walls. M. There shall be sufficient measuring taps for the furnace pressure measurement and protection. N. The Bidder shall provide the boiler tube leak detection system of a wall welded contact type. Complete system including twenty(20) sensors, electronic cubicle, workstation, monitor(min. 21 inch) and printer shall be provided. Boiler tube leak detection system shall be interfaced with PCS for the monitoring and alarm in CCR. O. The Bidder shall provide the furnace temperature monitoring system with laser type. Complete system including fifteen(15) pairs of laser sensors, electronic cubicle, workstation, monitor(min. 21 inch) and printer shall be provided. Furnace temperature monitoring system shall have capability of making thermography for thermal distribution of combustion zone and be interfaced with PCS for the temperature monitoring in CCR. P. Division water wall in the furnace shall not be allowed. 6.1.1.3 Steam drum A. The steam drum shall be of fusion welded construction fabricated from steel plate, and equipped with two(2) 450mm diameter manholes. The inside surfaces of the drum shall be shop shot-blasted leaving smooth, clean surfaces. The steam drum shall have a min. 3.2mm corrosion allowance above ASME min. wall thickness.
6.1-8 KHABAT TPP UNITS 1&2 - VOLUME I
B. The steam drum shall be equipped with the following internals. 1) Internal feed distribution piping and supports. 2) Continuous blowdown collection piping and supports. 3) Chemical feed distribution piping and supports. 4) Steam deflecting baffles 5) Steam/water separating devices designed to ensure a minimum steam pressure drop and to provide a maximum free space in drum and a minimum carryover of impurities into the superheater. C. All drum internals shall be fabricated in sizes to permit removal from the drum through manholes. D. Necessary welding end inlet and outlet connections and nozzles shall be provided by the Bidder to accommodate the required valves and accessories. E. The following drum accessories shall be provided ; 1) Level transmitters, level gauges and isolation valves(Left, right, center) 2) Safety valves with piping including common silencer. 3) Double blow-off valves including motor operated valve. 4) Vent valves including motor operated valve. 5) Remote control metering valve including inching motor operation for continuous blowdown 6) Thermocouples 7) Connections for instruments 8) Local pressure gauge with valves
6.1-9 KHABAT TPP UNITS 1&2 - VOLUME I
F. The necessary drum supports shall be furnished. G. Twelve(12)
ports
electrode
type,
bi-color guage systems shall be
provided at each side of the drum. H. The bi-color gauge glass of the each side of the drum shall be furnished. I. Electronic level indicators for monitoring drum level locally and in central control room, possible to distinguish between water and steam shall be supplied. Three(3) drum level transmitters and three(3) drum pressure transmitters for pressure compensation shall be supplied for drum. The drum level signal used for control purposes shall be the median of the three and outputs shall be provided for hardwired recording of the median and indication of the two levels. Drum level high and low trip contacts shall be provided for the boiler control system. 6.1.1.4 Superheater and reheater A. The superheater and reheater shall provide uniform distribution of steam and temperature at all loads, and provide thermal expansion of headers, tubes, spacers and supports, and shall be accessible for cleaning and removal of elements. B. The superheater and reheate tube material of high temperature zone shall be selected material to resist vanadium attack. C. The Bidder shall arrange the superheater and reheater tube banks as conveniently as possible to perform maintenance and periodic inspection. The Bidder shall describe what programs are being undertaken, if any, to resolve problems of gas side corrosion and erosion of superheater and reheater tube materials at elevated temperatures.
Tube sections of
superheater and reheater shall be arranged with clear spacing between tubes in the gas flow at least equal to tube diameter. Tubes shall be arranged in parallel rows.
6.1-10 KHABAT TPP UNITS 1&2 - VOLUME I
Tube banks in the convective pass may have minimum baffling installed for the prevention of acoustical standing wave formation. Staggered spacing and extended fins and studs will not be accepted. Maximum depth of bank of tubes shall not exceed twice the rated throw of soot blowers or 2.0 meter, whichever is less. Space shall be allowed between banks for retractable soot blowers. D. The minimum wall thickness of superheater and reheater tubes for corrosion allowance shall not be less than 1.5 mm for high temperature zone and 1.0 mm for low temperature zone. E. All superheater and reheater tube joints including connection to headers shall be of welded construction in accordance with ASME Section I. F. Superheater and reheater tubes shall be arranged and terminated in outlet headers in a manner which will yield through mixing of the steam, thereby resulting in equal temperature at each of the main steam and reheat steam outlets. G. Tube connections shall be shop-welded stub ends on headers. Stub ends shall be prepared for field welding of superheater and reheater tubes. Any welding of ferritic to austenitic stainless metals shall be done in the Bidder's shop. H. For the pendant type superheater and reheater, the Bidder verify that special consideration was given to his design to minimize temperature difference of each tube due to drain plugging during start-up and that his experience of such design has not shown any adverse effect to the steam generator operation capability. I. The minimum temperature control range of superheater and reheater shall be, as a minimum, 55 % of MGR to BMCR and 50 % of MGR to BMCR respectively when firing the design fuel oil. J. Provisions shall be included to prevent a temperature unbalance between superheater sections and between reheater sections. 6.1-11 KHABAT TPP UNITS 1&2 - VOLUME I
K. Peaking maximum gas velocity through tube banks shall not exceed 21 m/sec at any location at all ratings. Space shall be provided in convection pass for addition of a minimum of 10 % more superheater and reheater surface, if required. L. Spacers and hangers for superheater and reheater tubes shall be designed to provide for appropriate sliding expansion, and shall be of material suitable for temperature encountered, and shall be steam or water cooled where necessary. M. All headers shall be external to the gas stream, unless otherwise approved by KNOC , and shall be provided with welded inspection hole covers as required for inspection. Inlet and outlet headers and/or lead pipes shall be provided thermowells with thermocouples and test connections for pressure gauge and/or transmitter. The metal and pad thermocouples shall be provided with enough length wires to local temperature transmitter boxes. The length will be fixed at the detail design. 6.1.1.5 Attemperators A. Superheater steam attemperator shall be provided with two(2) stages. B. Reheater steam attemperators for emergency use and back-up control of reheat steam temperature shall be provided. C. The number of stages of the attemperators will be left for the Bidder. D. Maximum spray flow rate of superheater and reheater shall not exceed 7% and 1.5% respectively at any load when firing oil. E. The Bidder shall be provided with attemperator control valve, nonreturn valve, flow nozzle and bypass system. 6.1.1.6 Economizer
6.1-12 KHABAT TPP UNITS 1&2 - VOLUME I
A. The economizer shall be of a continuous loop drainable type and arranged for the upward flow of water and downward flow of flue gas. Staggered spacing and extended fins or studs will not be accepted. The horizontal banking tubes which are located above economizer shall be ensured an enough clear space for automatic tube welding. B. Economizer shall be arranged in banks of not more than 2.0 meters depth with mass soot blowers between banks. C. The minimum wall thickness of economizer tube for corrosion allowance shall not be less than 1.0 mm. D. Thermocouples with protection wells shall be provided by the Bidder. Where required for access and inspection, doors shall be provided with tight gasketed joints. E. All headers shall be external to the gas stream unless otherwise approved by KNOC and shall be provided with welded inspection hole covers as required for inspection. Inlet and outlet headers and/or lead pipe shall be provided thermowells with thermocouples and test connections for pressure gauge and/or transmitters. The inlet feed water line of economizer shall be provided with motor operated shut off valve and non-return valve. 6.1.1.7 Structural steel A. As used in this specification, the term “structural steel"
includes all
building and support structural steels, duct and pipe supports, all miscellaneous platforms, handrails, girts, purlins, girders, trusses, floor plates, metal roof decking and other steel designed to support superimposed loads and platework. B. Structural steel design engineering and erection shall be in accordance with UBC and AISC as amended to date of contract award and/or applicable local building codes.
6.1-13 KHABAT TPP UNITS 1&2 - VOLUME I
C. Structural steel framing and erection shall be in accordance with AISC Code of Standard Practice for Steel Buildings and specification for Bridges and AISC Structural Steel for Buildings as amended to date of contract award. D. Structural steel and plates shall conform to the ASTM designation A 36 and A 572 as amended to date of contract award. The Bidder shall furnish KNOC five (5) copies of the material test reports with Bidder's certificate on chemical composition and physical properties as described in the above ASTM standard specifications. E. All steel connections may be structurally welded and seal welded, or bolted with high strength structural bolts conforming to ASTM A 325 or A 490. F. The complete unit together with the steelwork shall be designed for a seismic force. G. The complete unit together with the steelwork shall be capable of withstanding wind loading. H. The structural steel design by the Bidder shall make his equipment selfsupporting. The structural steel shall also support loads imposed by the required walkways, platforms, stairways and ladders, elevator access platforms, and in addition, such loads as may be imposed by the KNOC 's piping, elevator access platforms, electrical cable tray (with cable) and conduit and miscellaneous equipment.
Some of these additional loads
may be partially or totally supported by the structural steel. I. Structural steel shall be fabricated and shop assembled to the greatest extent possible and delivered to the jobsite ready for installation unless otherwise required by design and installation conditions or shipping limitations. J. The Bidder shall, in accordance with KNOC's time schedule, provide all information required for the design of adjacent or connecting steelwork furnished by KNOC.
6.1-14 KHABAT TPP UNITS 1&2 - VOLUME I
K. The Bidder shall furnish the complete structural buckstay and hanger system. L. All welding shall be in accordance with the Structural Welding Code AWS D 1.1 as amended to date of contract award. M. Base plates shall be furnished by the Bidder. The top bearing surfaces of the base plates shall be true plain surface after cutting, either by re-rolling, pressing, planing, or milling with all beads, burrs and deformations along the edges and holes removed.
Base plates shall be center punched and
scribed. They shall be provided with levelling nuts and grout holes. Bottoms of base plates will be established approximately one(1) meter below finished floor elevation. All horizontal column base shear shall be transferred through bearing of the base plates and shear key on the foundation concrete in accordance with ACI 318 as amended to date. N. Columns shall be milled at the bottom and at splices for a full bearing surface perpendicular to the longitudinal axis and to exact lengths required. Where welding is required, edges shall be properly prepared and free of any harmful foreign material. O. Filler and splice plates shall have full surface contact, with all beads, burrs and other deformations removed from along the edges and around the holes. P. Anchor bolts and nuts shall be furnished by the Bidder. The Bidder shall specify the anchor bolt sizes and furnish an anchor bolt setting drawing. Q. Two (2) sets of stairs shall be provided by the Bidder, one(1) on each side of the steam generator. All stair treads shall have checkered nosings and be similar to grating. Slip ladders will not be permitted.
6.1-15 KHABAT TPP UNITS 1&2 - VOLUME I
R. The top of each boiler shall be provided with a suitable sun and weather protection canopy which extends downward so as to give protection to all access and operating platforms down to cover the bottom burner level. The canopy shall be provided with suitable ventilation louvers and shall slope towards gutters for collecting rainwater that shall run to the site drains. Operating platforms and instrument and electrical panels shall also be provided with suitable sun and weather protection canopies. S. The last elevator stop and one of the stairway landings shall terminate on the roof. Termination of the stairway shall be an enclosed and waterproof structure located on the roof. T. The Bidder shall submit engineering drawings, and fabrication and erection drawings in which the marking of the structural steel number for erection can be easily recognized and distinguished. U.
Material improperly detailed or wrongly fabricated which necessitates extra field work shall be the responsibility of the Bidder who shall bear the entire cost of the correction or shop errors and the replacement of material.
V.
Checkered plates at the burner location shall be used for platforms, and the remaining platform shall be grating for easy operation and maintenance of boiler.
W. The surface area calculation of the structural steel shall be submitted with the bill of material list of the structural steel. 6.1.1.8 Soot blowing system A. Adeq uat e soot blower ar r ang em ent sho wing num ber , t ype and location shall be provided to ensure that the heating surface of the boiler and air preheaters can be kept free of fouling, and the conditions of operation and the guaranteed gas outlet temperature can be maintained continuously. B. The sootblowers shall be automatically operated by time interval and boiler conditions. 6.1-16 KHABAT TPP UNITS 1&2 - VOLUME I
C. The sootblowers shall be capable of maintaining the boiler in a clean condition when operating at any loads with the fuel oil. The Bidder shall advise the minimum pressure and corresponding load at which satisfactory operation of the blowers can be maintained. D. Provision shall be made for installation of any additional sootblowers in the superheater, reheater, economizer and air preheaters which may be found necessary to enable the plant to satisfy the requirements of the specification. E. If,
anytime within
the guarantee period of the Bidder, it is found that
additional sootblowers are required, the Bidder shall provide all materials and labor to furnish and install the additional units including all piping, wiring, controls, and platforms with structural steel, at his own expense, and to integrate the additional blowers into the system. F. The sootblowing system shall include all necessary blowers, electric driver motors, all piping including automatic drain system, piping, control valve, motorized valves, safety valves, switches, hoses, electrical accessories, relays, support frames, hangers and supports. The pressure control valve for sootblowing steam shall be more than two (2) stage controlled. The Bidder shall provide complete instrumentation and controls. Sootblower piping drains shall be routed to the drain tank or suitable location selected by KNOC . G. Sootblowing medium shall be the steam suitably extracted from between primary superheater and final superheater. The automatic drain shall be possible according to steam quality. H. The soot blowers for the air preheaters shall have a second source of supply from the auxiliary steam system as specified.
6.1-17 KHABAT TPP UNITS 1&2 - VOLUME I
I. The Bidder shall state maximum quantity of steam required for blowing for each blower offered, and maximum quantity of steam required for each 24 hours to keep unit in clean condition. J. Provisions with handcrank shall be included to manually retract equipment in case of power loss. K. Sootblower control system shall be furnished with programmable logic controller(PLC), interface devices with PCS, programmable loader, motor starters and accessories and provisions for control of additional sootblower. Bidder can incorporate sootblower controls into PCS. L. The following safeguard and interlocks shall be furnished. 1) Loss of steam for blowing 2) Failure to complete time cycle for blowing 3) Drop in steam pressure 4) Reset device 5) Time delay M. Operator workstation shall be provided for the control and monitoring of the sootblowing system. The process graphic diagrams shall show the following monitoring measurements and which blower or group of blowers are operating and physical location in reference to the steam generator. 1) Steam flow 2) Steam pressure/temperature 3) Drain pressure/temperature 4) Other operating graphics
6.1-18 KHABAT TPP UNITS 1&2 - VOLUME I
N. All retractable blowers will immediately retract automatically on motor overload or reduction of blowing pressure. The following interlocks shall be included ; 1) No blowing medium 2) Low header pressure 3) Elapsed time interlock 4) Loss of voltage interlock 5) Magnetic overload interlock 6.1.1.9 High pressure bypass system A.
A complete high pressure(HP) bypass system shall be provided by the Bidder. The equipment furnished by the Bidder shall include, but not necessarily be limited to the following ; 1) High pressure bypass control valves. 2) Attemperating spray water control valves and isolation valves. 3) Necessary piping. 4) Pressure and temperature control system to operate the bypass control valves and the spray water control valves. 5) Hydraulic power units and control fluid piping to the actuators
B.
One(1) high pressure bypass control valves shall be of 40% capacity and high pressure bypass control valves shall be installed in main steam connecting pipes, respectively.
C.
The bypass control valves shall be provided with low velocity trim. This bypass system will dump steam from the main steam lines into the cold reheat system and be controlled by the pressure in the main steam system. Spray water for de-superheating will be supplied from the boiler feed pump discharge to the spray water control valve.
D.
The
Bidder
shall
pressure/temperature
provide
all
transmitters,
necessary smart
pressure
positioner
with
switches, position
transmitters and installation materials, etc.
6.1-19 KHABAT TPP UNITS 1&2 - VOLUME I
E.
High pressure bypass system shall be controlled and monitored in the PCS.
6.1.1.10 Piping and valves A.
Piping 1) All
required
acid or chemical cleaning connections shall be
provided for KNOC's chemical cleaning. Miscellaneous piping, including igniter fuel, air and service water piping shall be provided as specified herein. 2) The Bidder shall provide limit stops for lines
where there are
reactions from the Bidder furnished safety valves and power relief valves. B.
Valves 1) The
quantity, size and pressure rating of valves shall be in
accordance with the requirements of the ASME Boiler and Pressure Vessel Code.
The steam generators shall be equipped with the
necessary nozzles to accommodate all of the required valves and accessories. All boiler pressure connections must have double valves with weld end construction.
Drain valves shall be suitable for acid cleaning.
2) All hydraulic power system for hydraulic actuated valve shall have two(2) 100% capacity hydraulic pumps. 3) Safety Valves and Power Relief Valves. a) Safety
valves
including
one(1) set
hydraulic jack
shall be
provided on drum, superheater and reheater. Number and type of valves shall be in accordance with ASME Boiler and Pressure Vessel Code. Safety valves shall be of a type which will reseat at a pressure above the 96% of set pressure after operation. Each safety valve shall be supplied with a suitable gag. b) Power
relief
valves
with a full size shutoff gate valve shall
be provided on the superheater outlet header. The power relief valve shall be an addition to the number of valves required on the superheater by the boiler code, and shall be actuated by superheater pressure. The power relief valves shall have a capacity not less than 5 percent of maximum superheater outlet flow. 6.1-20 KHABAT TPP UNITS 1&2 - VOLUME I
c) The Bidder shall furnish silencers for safety valves and power relief valves.
The silencers are preferred to be arranged for a
combined and reverse flow type. d) The
Bidder
shall
supply
walkways
and
stairs
to allow
access to superheater power relief valves and silencers up to roof. Slip ladders will not be permitted. e) The complete controls
for
safety
valves
shall
be provided
including control logic hardware(system), all instruments, field housings, installation materials, etc. 4) Drain and Vent Valves All drain and vent valves for steam and water headers for start-up and shutdown systems shall be motorized type suitable for remote and automatic operation. All drain and vent valves shall be installed as close as possible to the source, accessible from the boiler platforms. The downstream of drain and vent valves shall be grouped to common lines considering the function of boiler design. 5) Sample Valves Sample valves for sample nozzles shall be stainless steel and socket weld construction. 6) Control
valves,
solenoid
valves,
valve motor operators and
electrical valve actuators and accessories shall be supplied according to this specification.. 7) Root Valves. All root valves for instruments shall have DN25 outlet tap connection and shall be designed in accordance with related codes and standards. 6.1.1.11 Steam generator setting A.
All
refractories,
brick,
tile, fittings, bonding, seals, clays, cements,
packings, insulation and other materials required to make complete setting for steam generator and furnace shall be provided. B.
Enclosure shall
include
a
membrane wall or a welded steel plate
casing fastened directly to furnace tubes, necessary insulation and an outer lagging or ribbed type aluminum alloy 3004 with pebbled finish, not less than 1.0mm thick.
6.1-21 KHABAT TPP UNITS 1&2 - VOLUME I
Furnace and rear pass enclosure walls shall be suitable for water washing. Sealing boxes shall be arranged where the superheater and the reheater bundles penetrate the furnace vertical waterwalls and the furnace roof. Special care shall be required to the seal design of boiler opening. The rounded configuration of sealing box corner and sleeves at penetration part shall be applied for thermal stress reduction. C.
Hinged access doors, arranged to permit convenient and safe access for maintenance, shall be provided at floor and platform levels. Access and observation doors shall be also provided to permit access to all compartments. diameter.
6.1.2
Access doors shall be not less than 500 mm in
All doors shall be provided with seals.
Draft system
6.1.2.1 Air preheaters A.
Two(2) 50% regenerative vertical type air preheaters per unit shall be provided to heat the combustion air.
B.
The regenerative air preheater shall be sized at BMCR condition.
C.
Air preheater rotor shall be driven by an electric motor through a totally enclosed speed reduction drive unit and a back-up auxiliary air motor driver complete with solenoid valve, strainer, piping, air set etc., that will start automatically upon failure of the electric motor, or remote manually or locally.
D.
The maximum air preheater leakage shall be less than nine(9) % of the gas flow entering the heater at BMCR load.
E.
Rotor shell shall be constructed of steel plates, not less than 12 mm thick, and shall be amply braced to prevent deformation.
Shaft shall be of
corrosion resistant material where exposed to flue gases. Heating elements shall be basket type and shall be readily removable. Platforms at the air preheater level shall be provided for basket laydown. Material for hot end heating elements shall be carbon steel plate of thickness not less than 0.6 mm. Material for intermediate section heating element shall be corrosion resistant low alloy steel(CRLS) plate of thickness not less than 0.8 mm. Material for cold end heating elements shall be enamel coated steel plates of thickness not less than 1.2 mm. 6.1-22 KHABAT TPP UNITS 1&2 - VOLUME I
Material of the heating element baskets shall be corrosion resistant low alloy steel (CRLS). F.
Radial bearings shall be self-aligning, antifriction type. Thrust bearings shall be pivotal segmental construction of antifriction type, employing the flat cylindrical principle or antifriction type of taper roller thrust bearing. Bearing housings shall be oil-tight and readily accessible. A complete shop-assembled oil lubrication system shall be provided including oil reservoir, pump with motor, oil coolers, piping with hangers and supports, temperature switches, instrument, and alarm contact.
G. Housing shall be fabricated of welded steel plate not less than 6 mm thick, and shall be rigidly braced against deformation and stiffened, especially where used as a bearing support. Connection shall include angle flanges for attachment to air and gas ducts.
Access doors
shall
be air and gas tight when closed and shall be adequate size for inspection, cleaning, and replacement of parts. Provisions shall be made for expansion and contraction so that no undue strain is placed on component parts, with due regard to differential expansion of the heater elements and differences in the pressure of the media. Provisions shall be made to minimize temperature stratification in the gas outlet duct from air preheater. H.
Access
for
replacement
purposes shall be provided for all air
preheater baskets. Suitable beams, lifting hoist and monorail which shall be permanently installed, shall be provided for cold end and intermediate basket removal.
These baskets shall have attachments to facilitate
handling without the use of welding equipment. I.
The Bidder shall show diagrammatically, in his proposal, how his air preheater system for combustion air is arranged.
J.
“Stop Rotation" alarm device shall be provided for each rotating element of the air preheater. Output signals from the device shall be provided for use in Bidder's control and monitoring system and in PCS.
K.
Steam cleaning shall be provided as needed with water-wash feature incorporated in the hot end cleaning device. The cleaning devices controls shall be incorporated into the sootblower control panel. The water washing device and wash water heating system with chemical injection device shall be provided. 6.1-23 KHABAT TPP UNITS 1&2 - VOLUME I
L.
Fire protection system for air preheater shall be provided.
M. Isolation dampers shall be provided on the gas inlet and air outlet side of the air preheaters.
Provision shall be made to install blanking plates
which shall provide tight shut off to allow maintenance and repair work to one air preheater while the unit is in service. Each isolation damper shall be assembled in its own separate frame and shall be designed to minimize binding from dirt and combustion products. Actuators shall be either electric or pneumatic. N.
The layout of gas ducts upstream of the air preheater as well as the air preheater arrangement shall be selected so as to minimize ash pluggage of the air preheater elements.
O. The Bidder shall provide the complete control system including local control panels, instruments with installation materials. etc. 6.1.2.2 Steam coil air heater A.
Two (2) 50% steam coil air heaters per unit shall be provided between forced draft fan and air preheater to maintain minimum average cold end metal temperature as required by effective cold end corrosion protection with minimum temperature specified in job site condition when burning specified fuel oil.
B.
Coil sections shall be of heavy duty type design to provide positive drainage to prevent freezing. Tubes shall be steel and be a minimum of 25 mm OD provided with fins. Fins shall of the mechanically bonded to the tube, or of the integral type with fins extruded directly from the walls. Fin material shall be copper and thickness of fin shall not be less than average 0.4 mm. The fin shall not move relative to the tube as a result of expansion and contraction.
C.
Minus tolerance shall not be allowed for the thickness of heater tubes and fins.
D.
A draw type duct casing shall be provided and shall consist of a rigid frame constructed of 6 mm formed plates or equivalent structural channels with suitable braces.
The arrangement shall be such as to
assure self draining of the tubes, headers and pipe to prevent water hammering at any load. Adequate space shall be provided for coil removal. E.
The stubs on the headers shall have end preparation for welding to the tubes in accordance with ASME section Ⅰor equivalent codes. 6.1-24 KHABAT TPP UNITS 1&2 - VOLUME I
6.1.2.3 Fans A.
General Number of fans and drivers, and types provided for each steam generator shall be as follows ; 1) Two(2) 50% centrifugal type Forced Draft Fans (FDF) with backward inclined airfoil blade and constant speed drivers. 2) Two(2) 50% centrifugal type Combined Induced Draft Fans(CIDF) with backward inclined airfoil blade and constant speed drivers. 3) One(1) 100% centrifugal type Gas Recirculation Fans(GRF) with constant speed drivers and automatic clutched turning device, if required. 4) Two(2) 100% (one stand-by) centrifugal type Scanner Cooling Air Fans (SCAF) with constant speed drivers. 5) Two(2) 100% (one stand-by) centrifugal type sealing air fans(SAF) with constant speed drivers, if required. 6) The Bidder shall provide electric motor driver for each fan. The Bidder shall be responsible for the selection of the motor characteristics, the motor mounting, all accessories necessary to satisfy the requirements of the fan motor driver unit in all operating mode. 7) In those instances where a variance from these instructions can be shown not to detrimentally affect the performance or serviceability of the fans, the Bidder may include appropriate exceptions in his proposal.
The Bidder shall also enumerate his reasons for these
variances in his proposal. B.
Design Requirements 1) Fan design speed shall not exceed 1,000 rpm for forced draft fans, 600 rpm for gas recirculation fans, 750 rpm for induced draft fans, 1,500 rpm for scanner cooling air fans. 2) Fans shall be designed for continuous operation either singly or in parallel over their full operating range without excessive vibration, surging, or other undesirable character- istics. 3) Fan design efficiency shall have the maximum value at BMCR and high efficiency shall be maintained over a wide range of fan output. 4) Test block conditions of fan size and performance shall have adequate margin as follows ; 6.1-25 KHABAT TPP UNITS 1&2 - VOLUME I
a) Forced draft fans shall have 20 % margin for volume and 25 % margin for static pressure at the ambient temperature of 30 degree C. b) Induced draft fans shall have 20 % margin for volume and 25 % margin for static pressure and 15 degree C margin for gas temperature. c) Gas recirculation fan shall have 25 % margin for volume and 30 % margin for static pressure and 28 degree C margin for gas temperature, if required. 5) The Bidder shall consider the draft losses of across the electrostatic precipitator through the stack in selecting the combined induced draft fan. 6) The Bidder shall provide the following characteristic curves and performance curves for each fan. a) Static pressure versus capacity over entire range. b) Fan brake horsepower with inlet vane control over entire range of capacity. c) Efficiency. d) System
resistance
curve
including
30%MGR,
50%MGR,
75%MGR, 100% MGR, BMCR and test block points. e) Surging curves Performance data to be supplied by the fan manufacturer shall include performance with and without evase. 7) The sound levels generated by furnished draft equipment during normal operation shall not exceed 85 dBA weighted, slow response, at a horizontal distance of one(1) meter from all surfaces of the equipment and at a height of 1.5 meter above or below the platform or floor on which the equipment is mounted. The Bidder shall complete the data in the bid form for sound levels from basic draft equipment, together with his recommendations for sound reduction modifications. 8) Maximum acceptable vibration at any load and speed up to 110 % of design speed shall not exceed 2 mils double amplitude for up to 750 rpm fans, 1.5 mils double amplitude for 1000 rpm fans, and 1.0 mils
6.1-26 KHABAT TPP UNITS 1&2 - VOLUME I
double amplitude for 1500 rpm fans in operation when mounted on foundation. Vibration shall be measured at the bearing housing. 9) Where auxiliary
equipment
such
as
dampers,
inlet
vanes,
silencers or inlet boxes are to be provided with the fans, draft losses will be added to the system requirements and the fan shall be selected for the sum of the pressure losses. 10) Shaft grounding devices
shall
be
provided by the Bidder to
prevent the bearing failures of fans due to electrostatic voltage. 11) Automatically engaged and disengaged turning device for gas recirculation fan shall be provided. 12) The fan rotor and impeller constructed to be readily removed. 13) The band brake unit shall be fitted to prevent the stack draught prolonging the run down rate of the induced draft fans or rotating it while out of service. This brake shall be arranged to operate automatically at rundown of the fan and automatically released as part of the fan starting sequence. 14) The Bidder shall provide the seaing air fans (if required) for preventing the shaft from corrosion. C.
Construction Features 1) Housing and inlet boxes a) Fan scrolls and inlet boxes shall be of welded steel plate construction. b) For fan service
where
operating
temperatures
are
in
excess of 80 degree C, fan housing and inlet boxes shall be of not less than 13 mm in thickness. c) Where C,
operating
temperatures
are
less
than
80
degree
a minimum thickness of 10 mm shall be furnished.
d) Sufficient bracing
and
reinforcements shall be employed to
withstand imposed pressures without vibration or distortion during operation for the life of the fan. e) Scrolls and boxes shall be fitted with drains of at least 100 mm diameter pipes and positioned in the bottom of the housings and inlet boxes.
Each drain shall be provided with an isolation valve.
f) The housing and inlet boxes shall be provided with suitable removable sections or split for access and removal of the rotor.
6.1-27 KHABAT TPP UNITS 1&2 - VOLUME I
g) Access doors shall be provided for entry into the fan housing and inlet boxes. 2) Rotor a) The rotor shall be of the all welded construction utilizing the ASTM specification materials or approved equivalents. Where a high strength alloy steel is to be employed, the Bidder shall notify KNOC to this effect including what components and alloys are to be furnished. b) Af t er t he f inal m achining t he r ot or shall be posit ioned permanently on its shaft and dynamically balanced in the manufacturer's plant. c) The rotor assembly shall be designed so that its installed resonant speed is not less than 1.30 times the full operating speed of the rotor for all clean air or gas applications. d) During rotation, the run out of similar points on the rotor structure shall not exceed a deviation from the median path of 3/8 of one(1) % of the wheel diameter axially and 3/16 of one(1) % of the wheel diameter radially. 3) Bearings a) Each fan shall have two bearings with rotor suspended between bearings. b) Radial bearings for all fans shall be of the self-aligning sleeve type with horizontally split housing and adequate seals to prevent entrance of dust. c) Main Shaft bearings shall be located out of gas stream. d) Thrust bearing shall be manufacturer's standard. e) Bearing housing shall be arranged for complete draining of the cooling medium. f) The double inlet fans shall be designed to withstand the thrust unbalance resulting from the shut-off of one inlet of the double inlet fan while the other inlet is open. g) The construction of bearing pedestals shall be such as to permit shimming and shall also allow disassembling the bearing without having to remove the rotor. Soleplates, anchor bolts and fittings shall be included.
6.1-28 KHABAT TPP UNITS 1&2 - VOLUME I
h) Each fan shall be fitted with a fixed bearing at the motor side sufficient to locate the fan rotor in its proper running position. Overhung wheels are not acceptable. i) Each bearing housing shall have surfaces tapped to permit the installation of vibration monitors mounted 90°apart. 4) Shaft couplings a) The coupling shall be of the limited end float type. The coupling of fan and motor shall be mounted in the manufacturer's shop. A suitably designed coupling guard shall be furnished by the fan Bidder. This guard shall comply with OSHA requirements. b) The coupling shall be attached to the shaft by either keying or by having a shrinking fit. c) The flexible couplings shall be non-lubricated type. d) All coup ling s shall be bot h st at icall y and dynam ica ll y balanced to minimize vibration of the couplings. 5) Inlet vanes a) I n l e t v a n e s a r e o n e o f t h e p r e s s u r e a n d v o l u m e c o n t r o l devices for controlling the operation of the fans. b) The vanes shall be equipped with the necessary linkage arm for attachment of a control drive furnished by the Bidder. Particular attention shall be given to the design of the cross connection of the inlet vanes on a double inlet fan to minimize the possibility of one vane assembly suddenly closing while the fan is in operation. The Bidder shall provide a design of vane control where moving parts, bearing, etc., are out of the gas stream entering the fan. Access to these devices shall be provided for normal maintenance and inspection while the fan is stopped. c) The vane control blades
shall
be
supported
in bearings at
each end of the blade spindle. Bearings shall be provided with the permanently lubricated selfaligning type. d) The entire vane control assembly shall be of a design so that it can be split horizontally for ease of access to and removal of the fan rotor. 6.1-29 KHABAT TPP UNITS 1&2 - VOLUME I
e) All fans equipped with variable inlet vanes shall be provided with a spoiler device or dorsal fin to assist in minimizing ductwork and fan casing pulsations when the inlet vanes are in the partially closed position. D.
Lubricating Oil System 1) Lubrication system for bearings for FDF, CIDF, GRF and their drivers shall be by water cooled circulating lube oil system. 2) Lubricating oil system for FDF, CIDF, GRF, and their drivers shall consist of one(1) oil reservoir, indirect type electric heaters, filters, two(2) 100 % capacity oil pumps with motors, two(2) 100 % capacity oil coolers, piping, valves, flexible connections, and instruments and controls necessary for operation. 3) Joints in lube oil piping shall be welded where practicable. Flanged joints shall be used only where necessary for assembly and dismantling of oil piping. Connections and provisions shall be made for field flushing of the system.
E.
Dampers 1) Each fan shall be provided with a discharge damper and inlet damper(s)/vane(s) to permit isolation of an idle fan while the unit is in service. 2) The dampers shall be housed in heavy channel frames. Each damper leaf shall be supported by and welded to a shaft spindle and supported in bearings at each end. 3) T hese bear ing s shall be per m anent l y lu b r icat ed and self aligning. In no case shall grease be utilized. 4) The dampers shall be provided with the necessary linkage arm for attachment of a control drive furnished by the Bidder. 5) Particular attention shall be given to the design of the cross connection of the inlet dampers on a double inlet fan to minimize the possibility of one damper assembly suddenly closing while the fan is in operation. 6) The damper tightness will be
such
that
leakage across the
damper shall not exceed two(2) percent of the specified maximum design flow. F.
Instrumentation and Control
6.1-30 KHABAT TPP UNITS 1&2 - VOLUME I
1) Instrumentation shall include all pressure, temperature, flow, and level switches required for interlocks and alarms, all pressure gauges, thermometers, and other devices required for operation. 2) Two(2) thermocouples shall be furnished on thrust bearing ; one for the thrust face and the other for radial journal. 3) Each radial bearing shall be furnished with a vibration pickup, a vibration transducer and special cable for installation between the pickup unit and the monitor in accordance with the section 8 of this specification. 6.1.2.4 Flues, ducts, dampers, and windbox A.
The Bidder shall furnish air ducts
and
gas flues connecting fans,
economizer, air preheater, electrostatic precipitator, stack and windbox including complete air ducts to FD fans, dampers, seal air ducts, expansion joints, supports, deflecting vanes, stiffener angles, insulating clips, windboxes, etc. The air intake location of forced draft fans shall be arranged penthouse levels of the boiler building to utilize the radiation heat rejected from the boiler, and shall be provided with the silencers. The gas recirculation system, if required, shall be designed and the design scope of this system is all recirculation fan and duct with necessary appurtenance. B.
The velocity of
air or gas in the ductwork shall not exceed 20 m/sec
at any point, at the maximum continuous rating of the steam generator. The measurement of total air flow of combustion control shall be taken from the inlet of FD fans supplying combustion air to the steam generator. The required length of straight duct shall be provided including suitable air flow measuring devices. Gas ducts shall be provided with suitable sampling connections. The suitable test and sample connection shall be located easily accessible, and shall be provided with suitable caps to seal them when not in use. In designing the flue gas system, the Bidder shall consider, in addition to the requirements of the proper gas velocity, gas distribution in the duct work, minimizing draft loss, and minimizing dust deposition on the floors of the breeching and on the surfaces of corrective devices, such as turning vanes, distribution plates, expansion joints, etc.
6.1-31 KHABAT TPP UNITS 1&2 - VOLUME I
The Bidder shall design and arrange the duct to distribute flue gas flow equally into the two electrostatic precipitator
streams.
Moreover, the Bidder shall incorporate the result of gas flow model studies in connection with electrostatic precipitator for the flue gas system between the downstream of the air preheater and the upstream of the induced draft fan. C.
Air ducts shall be fabricated of steel not less than 4.5mm thick. Gas ducts shall be fabricated of steel not less than 6.0 mm thick, shall be of corrosion resistant low alloy steel(CRLS). Air ducts and windbox shall be reinforced with steel angles and straps having a minimum thickness of 6.0 mm. Gas duct shall be furnished with supports to carry weight of duct, insulation, dust on the bottom, and vertical live load on horizontal projection of roof surface of 250 kg/m2. Air and gas ducts with internal flow area in excess of 10 m2 can be reinforced with internal bracing having a minimum thickness of 6.0 mm. Access doors shall be fabricated steel plate with positive closing mechanism, gas and air tight. Minimum size opening shall not be less than 400 mm on vertical and 500 mm on the horizontal axis. Steel plates bolted over access openings are not acceptable. The location and number of access doors will be reviewed by KNOC .
D.
Duct
and windbox shall be welded wherever practicable. Where not
welded, ducts and windbox shall have bolts not less than 8 mm in diameter spaced not more than 76 mm apart, and joints shall be sealwelded in the field. The windbox connected to the furnace wall tube shall be designed and arranged not to damage by mal-distributed air flow. E.
Expansion joints in the ducts shall be provided as required by the design to permit the free movement of the ducts without distortion and without inducing stresses at the air preheater and fans. The flexible elements for gas duct expansion joints shall be stainless steel for high temperatures zone, corten(or equal) for 1ow temperature zone . The flexible elements for air duct expansion joints shall be corrosion resistant low alloy steel or KNOC approved equal.
6.1-32 KHABAT TPP UNITS 1&2 - VOLUME I
F.
All plates
to be field welded shall be shop beveled or otherwise
prepared so that the field welding may be done without additional field preparation. Clips shall be shop welded to each section to facilitate alignment of the plates during field welding. G. Abrupt
turns
of
radius
of
less than five (5) diameters shall be
avoided, but if such turns are required, guide vanes shall be provided. Guide vanes shall be not thinner than 3 mm spaced to minimize draft loss, suitably welded, supported, and reinforced. Distribution plates and other corrective devices, such as teardrop vanes, shall be incorporated as required on duct transition pieces. H.
Permanent scaffold brackets shall
be
provided where required for
maintenance. I.
Spring
hanger
assemblies,
where required, shall be pre -engineered
and preset for movement and loading. All hanger and tie rod assemblies shall be adjustable. J.
Balanced
multiple
leaf
type
dampers
shall
be
provided in
separate, flanged duct sections with rigid shaft mounted on ball, roller or sleeve bearings arranged so as to be protected from excessive temperatures.
Bearing
lubrication
shall
be
capable
of
being
accomplished from permanent access platforms which shall be provided. Dampers shall operate freely in all positions and shall make tight seals when closed. each damper shall have an external position indicator. Automatic controlled dampers shall have a lever with clamping device for manual operation. Dampers shall be suitable for throttling to 10 % of maximum rating. Dampers for air ducts shall be louver type and shall employ a strip of spring steel at the blade edge which closes against a knife edge stop. Dampers for air ducts shall be louver type and shall employ a strip of spring steel at the blade edge which closes against a knife dege stop. Dampers for gas flues shall employ an angle strip edge for high temperature service. K.
Power operators shall be provided for dampers requiring automatic control and non-modulating remote manual or automatic actuation. These shall include dampers in the burner and igniter control system which require remote operation or setting during normal startup, shutdown, or 6.1-33 KHABAT TPP UNITS 1&2 - VOLUME I
postemergency trip operation for the purpose of preventing fires or explosions due to retained fuel in the ducts, fuel pipes, furnace or steam generator passes. When air cylinders are furnished, they shall be equipped with integrally mounted pipes, solenoid valve actuator, air filter and regulator, with indicating gauge assembly suitable for the services. Two(2) adjustable limit switches of the double-pole-double-throw (DPDT) type shall be included for all power operated dampers for interlocking and monitoring in PCS. Modulating power operator shall have a position transmitter for feed back control. L.
The Bidder shall give a special consideration to the design of duct layout to accommodate the future installation of De-SOx facilities and shall furnish all of connecting flanges, dummy ducts and blind plates required for easy installation.
M. The Bidder shall provide duct design sheet, with his proposal, indicating the following data for each duct and windbox. 1) Mass flow, kg/h 2) Design temperature, degree C 3) Volume flow, m3/min 4) Specific volume, m3/kg 5) Maximum velocity, m/s 6) Maximum pressure (operating/transient), mm H2O gage 7) Design pressure (positive/negative), mm H2O gage 8) Duct area, m2 6.1.3
Fuel burning system
6.1.3.1 General A.
The steam generator shall be equipped with fuel oil and light oil burner systems which comply with NFPA standard.
B.
All
burners
shall
be
capable
of
maintaining stable operation
over the complete burner load range and a steam generator firing rate range equivalent to minimum/maximum steam generator capacity. C.
The fuel oil burning system shall be complete with fuel oil burners with steam atomizing type, supply and return flow control for all burners, associated piping and valves, windbox with dampers, instruments and 6.1-34 KHABAT TPP UNITS 1&2 - VOLUME I
controls, and other accessories required for integration with the system. The flow element type for flow control shall be the ultrasonic liquid flowmeter. D.
The light oil burning system shall be complete with automatic electric igniter assemblies, light oil burners with mechanical and/or air atomizing type, supply and/or return flow control for all burners, associated piping and valves, windbox with dampers, instruments and controls, and other accessories required for integration with the system.
E.
The light oil burning system shall be suitable for lighting the fuel oil burner and establishing stable flame conditions under all normal and abnormal operating conditions including off- stoichiometric combustion.
F.
The fuel oil burners shall be designed to burn fuel oil, complete with retractable oil guns, pneumatic retractors, air registers and vanes.
G. Light oil burners shall be designed to burn light oil complete with retractable oil guns, and shall be capable of carrying the steam generator load not less than 30 % of BMCR and during steam blowing out operating. H.
The ignition
system
shall
be
suitable
for
continuous or
intermittent operation. I.
The Bidder shall state in his proposal what provision is considered to improve the reliability of the ignition system.
J.
All parts of oil burners and associated equipment shall be suitable for continuous service with preheated air leaving the air preheaters.
K.
Each burner shall have a peep door with tinted glass to permit observation of flame, and a tight closing, hinged or swing door, if necessary.
L.
The fuel burning
equipment
shall be designed to be operable with
full automatic control during startup, normal operation and planned or emergency shutdown. 6.1.3.2 Fuel oil burner A.
Burners shall be capable of sustaining BMCR load with one gun out of service when burning fuel oil.
B.
Each burner shall have proper turndown range based on BMCR load without requiring change of any burner parts and without evidence of flame instability or other combustion difficulties in this range.
6.1-35 KHABAT TPP UNITS 1&2 - VOLUME I
C.
The Bidder shall be supplied low NOx type burners for NOx emission control.
D.
Burner shall be capable of withstanding the furnace heat with air leakage while not in service.
E.
Piping shall
include
the fuel
oil
piping,
and steam atomizing
piping. This shall include fuel oil burning pumps, in-line service tank suction heaters, fuel oil heaters and drain cooler, supply and return flow meter(indicating integrator type), all valves, fine duplex type strainers, regulators, accumulators, and automatic shut-off valves, leak check valves and flexible piping required for safe operation of the burners. Oil valves shall be designed so that the open or closed position is easily determined. Each connection to the burner shall have a manual shut-off valve. F.
A scavenging system for each oil atomizer shall be provided and shall be interlocked with the light oil system.
G. Openings and tubes for optical flame scanners shall be provided. H.
Provision shall be included for thermal expansions of pipe and equipment.
I.
The design of the oil piping and location of the shutoff valves shall prevent any oil from leaking into the windbox.
J.
Oil trip valve and burner control cabinets shall be furnished. Oil trip valve shall be solenoid or power cylinder operated.
K.
A single gun cleaning facility shall be provided (for each unit) at each side for each burner level.
6.1.3.3 Light oil burner A.
Piping shall include light oil supply and return piping, and air atomizing piping. This shall include supply oil line flowmeter(indicating integrator type), all valves, fine duplex type strainers, regulators, accumulators, and automatic shut-off valves, leak check valves and flexible piping required for safe operation of the burners and igniters. Oil valves shall be designed so that the open or closed position is easily determined. Each connection to the burner shall have a manual shut-off valve.
B.
A scavenging system for each oil atomizer shall be provided and shall be interlocked with the igniter control system.
C.
Light oil consumption rate during start-up operation shall be submitted data in his proposal. 6.1-36 KHABAT TPP UNITS 1&2 - VOLUME I
D.
Openings and tubes for optical flame scanners shall be provided.
E.
Provision
shall
be
included
for thermal expansions of pipe and
equipment. Flexible stainless steel hose shall be provided with the burners for connecting the burner piping to the light oil header. F.
The design of the oil piping and location of the shutoff valves shall prevent any oil from leaking into the windbox.
G. Oil trip valve and igniter control cabinets shall be furnished. There shall be one trip valve for the light oil system. Oil trip valve shall be solenoid or power cylinder operated. H.
A single gun cleaning facility shall be provided (for each unit) at each side for each burner level.
6.1.3.4 Igniter A.
The igniter shall be provided each oil burner for lighting.
B.
An automatic electric ignition system with electrodes, high voltage cables, transformers, relays, controls, mounting brackets, and all required accessories shall be provided. The control shall be automatic by limit switches on the igniter.
C.
The electric portions shall be designed for satisfactory operation in high temperature service.
D.
Interlock with the light oil shut-off valve that prevent opening of the oil valve without the igniter being energized shall be provided.
6.1.3.5 Emission control A.
The Bidder shall submit the expected NOx emission rate such as NO2 based on 3% O2 dry flue gas basis leaving air preheater at any load when burning the fuel oil. The Bidder also shall submit a report which takes into account all necessary design parameters that will allow compliance with the emission limitations specified above.
The means by which compliance is
accomplished is left entirely to the Bidder. The techniques by which compliance is achieved and the contribution by each technique shall be specified by the Bidder. B.
The following items used for the control of NOx emissions shall be incorporated into the original design. The expected reduction in boiler efficiency resulting from each technique shall be stated by the Bidder. 1) Off-Stoichiometric Combustion(OSC) 6.1-37 KHABAT TPP UNITS 1&2 - VOLUME I
2) Overfire Air Ports(OAP) The steam generator shall be equipped with overfire air ports (or DeNOx ports) capable of supplying the required percent of the total air flow for combustion. 3) Gas recirculation(GR) 4) Burner Control System and Boiler Control System. The automatic burner logic system shall have sufficient operating flexibility to permit satisfactory burner operation under all emission reduction techniques. 5) Any emission reduction technique considered by the Bidder to be technically feasible other than those specified above may be bid. If the above techniques can not meet the emission limit of NOx, the Bidder shall provid the SCR system. To enable KNOC to make a satisfactory evaluation, it is necessary for each Bidder to submit the steam generator efficiency changes associated with each technique. C.
The Bidder shall provide the ash burden and particle size in flue gas leaving the air preheater when firing the fuel oil.
6.1.4
Blow down system Blow down system is combined by blow down tank and flash tank, the flash tank supply re-flashed steam from blow down water to deaerator, intermittent blow down or drain flow in blow down tank, the water drains to drain pit thru over flower pipe. This blow down system is not operated continuously, the conductivity of boiler water in steam drum is checked in sampling cooler system automatically. When the conductivity value is higher than limit set point value, alarm is rung, operator open drain valve properly by remote device. Blow down system including drain tank and vent stack is insulated.
6.1.5
Instrumentation and controls A.
The Bidder shall furnish a complete instrumentation and controls necessary to meet the requirements of this specification, and that shall
6.1-38 KHABAT TPP UNITS 1&2 - VOLUME I
offer a high degree of reliability and safety to both personnel and apparatus. B.
Instrumentation and controls shall be designed in accordance with the section 8 of this technical specification unless otherwise specified in this section.
C.
All field instruments shall be weather-proof and dust-tight suitable for use under ambient conditions prevalent in a specific plant. Field instruments shall be installed in a vibration free location.
6.1-39 KHABAT TPP UNITS 1&2 - VOLUME I
6.2
Fuel Supply and Storage System
6.2.1
Plant fuels The Plant is to fire fuel oil under normal operating. During normal operation conditions the plant shall be operated with fuel oil. The light fuel oil system shall only operate during start-up when firing fuel oil. Typical fuel analyses are provided in Schedule A.
6.2.2
Oil filtering systems The fuel oil filtering system is for removing of impurity over the range of the fuel oil for suitable firing of the boiler. The fuel oil filtering system shall be generously sized to cope with a wide range of fuel qualities delivered to the site without the need of frequent cleaning. They shall be easily cleaned without the need to provide sealing material. The filter will be used in a power plant facility to fulfill the conditions of service.
6.2.2.1 Design and construction The filter furnished under this specification shall be designed to the requirements of the code/standard and this specification. Information on the material of the internal parts shall be given and submitted to the KNOC. The filter shall be designed to function in ASME B31.1 piping systems with the service conditions. Filter basket shall be removable for cleaning without removing the strainer from the pipeline. Cap threads, if used shall be straight, not tapered. Filter basket shall be designed capable of taking the full line operating pressure across a fully blocked filter without any deterioration, and shall be suitably reinforced as required to accommodate this feature. All filters shall undergo tests at the manufacturer's works in accordance with the specific requirements of the approved Code of Practice. The Bidder shall design to consider provisions against leakage, damage and failure of strainer major parts.
6.2-1 KHABAT TPP UNITS 1&2 - VOLUME I
The Bidder shall be responsible for selecting the pressure seal materials to be zero leakage. The Bidder shall describe the information which you need to let the Purchaser know in constructing. 6.2.3
Fuel oil supply and transfer systems
6.2.3.1
General The function of the fuel supply and transfer systems is to supply the fuel oils from the fuel storage tanks and, from there, to transfer oil to the inlets of the burners located in the respective boiler units under all ambient conditions. The fuel oil supply and transfer system shall also provide light fuel oil for the ignition of the burners and to the storage tanks of the emergency diesel generators and the fire fighting pumps. The design of the fuel supply and transfer system shall be such that the Plant is able to meet all of its operational requirements. Moreover, the system design shall achieve the minimum pressure, temperature and other conditions at the inlets to the burners in each Plant boiler unit.
6.2.3.2 Fuel oil An effective communications system shall be provided between the fuel interface points and the plant to ensure the routing of fuel oils to the appropriate fuel oil storage facilities and to avoid tank overfilling. The oil supply pressure to the storage facilities shall be observed at local and PCS by a pressure measurement system. Fuel oil service pump shall be installed in a fuel oil pump house which shall be a common pump house for all fuel oils. The fuel oil service pump capacity and system parameters shall be based on all power units operating at their maximum capacity taking account of the operational requirements of Section II, unit start ups and intermediate conditions when some units are not operating. The pump configuration shall include appropriate levels of redundancy including at least one pump set and its auxiliary equipment. All of the fuel oil fuel oil service pump skids shall discharge into a common 6.2-2 KHABAT TPP UNITS 1&2 - VOLUME I
header that shall then transfer fuel oil to the fuel oil heaters and then to each boiler unit. The fuel oil heaters shall be designed to heat the fuel to an appropriate temperature for atomization in the boiler burners and shall also incorporate a minimum redundancy represented by one spare heater unit. Appropriate oil recirculation facilities shall be provided to accommodate load fluctuations such that the Plant is able to meet all of its operational requirements. Duplex filtering and associated differential pressure switching/alarm and valve/drain facilities shall be provided on the inlet side of each fuel oil service pump skid. Each fuel oil service pump skid shall be complete with a differential pressure gauge and appropriate valves shall allow the isolation of each fuel oil service pump. Flow detectors and non-return valves shall provide pump protection, and pressure switches shall be used to sense the pressure at the pump suction and provide a trip/permissive signal for start-up. The fuel oil service pump discharge pressure shall be indicated on a local pressure gauge. Appropriate vents, drains and valves shall be provided. The flow element type for flow control shall be the ultrasonic liquid flow-meter. All of the fuel oil service pumps and heating facilities shall be located indoors in a purpose designed building. Tariff quality flow metering shall be provided as part of the fuel supply and transfer system. Each boiler unit shall have its own metering system for measuring the flow of oil to the respective boiler. Such metering shall maintain its accuracy over the full range of incoming flow rates during tank filling. Metering signals indicating the instantaneous and cumulative flow rates shall be provided to the central control room. Such metering shall be capable of being isolated for maintenance, and duplex filtration (with steam cleaning) and pressure differential measurement facilities shall be provided upstream of the metering for meter protection purposes. Facilities shall be provided to allow the drainage of the metering systems to a local drain pit. Fuel oil heaters shall be of the horizontal shell and U-tube type with removal 6.2-3 KHABAT TPP UNITS 1&2 - VOLUME I
tube bundle. The fuel oil heaters shall be TEMA type AEU. Fuel oil heaters shall be controlled with control valves located on the condensate discharge and will operate partially flooded with condensate. Heaters shall be designed for this operation and shall withstand any thermal stresses. 6.2.3.3
Light oil Light oil shall be delivered to the Plant by road tankers for storage on site. During normal operation the Plant shall be operated with fuel oil ; the light fuel oil system shall only operate during start-up on fuel oil. A tanker unloading station shall be provided and one(1) unloading pump skid lines of identical design shall enable one(1) road tankers to simultaneously supply light oil to the storage facilities. Each unloading pump skid shall be complete with a suction filter and differential pressure gauge located on the suction side of the unloading pump and appropriate vents and drains. Flow detectors shall also be provided on the suction side of each unloading pump. The discharge side of each unloading pump shall be provided with a nonreturn valve and a local pressure gauge to indicate the pump discharge pressure. Appropriate valves shall allow the isolation of each pump line. The tanker unloading shall be controlled at a local level once the tank to be filled is released by the central control room i.e the tank inlet valve is opened and all other routes are isolated. Tariff quality flow metering shall be provided to measure all road tanker unloading. Such metering shall be capable of being isolated for maintenance, and duplex filtration (with steam cleaning) and pressure differential measurement facilities shall be provided upstream of the metering for meter protection purposes. Such metering shall maintain its accuracy over the full range of incoming flow rates during tank filling. A metering signal indicating the instantaneous and cumulative flow rate shall be provided to the central control room. Facilities shall be provided to allow the drainage of the metering system to a local drain pit. Light oil service pumps shall be installed in the fuel oil pump house. The capacity and system parameters shall be based on starting all power units 6.2-4 KHABAT TPP UNITS 1&2 - VOLUME I
simultaneously. All of the light oil service pump skids shall discharge into a common header that shall then transfer light oil to each boiler unit. Light oil recirculation facilities shall be provided as appropriate. Duplex filtering and associated differential pressure transmitter and valve/drain facilities shall be provided on the inlet side of each fuel oil service pump skid. Each light oil service pump skid shall be complete with a differential pressure gauge and appropriate valves shall allow the isolation of each fuel oil service pump. Flow detectors and non-return valves shall provide pump protection, and pressure switches shall be used to sense the pressure at the pump suction and provide the signal for start-up. The light oil service pump discharge pressure shall be indicated on a local pressure gauge. Appropriate vents, drains and valves shall be provided. All of the light oil service pumps shall be located indoors in a purpose designed building together with the fuel oil forwarding facilities. Two (2) additional 100% capacity light oil service pump skid and its associated filtering, venting, pressure monitoring, draining, pump protection and valves etc. facilities shall also be provided in the common fuel pumping station to transfer light oil to the emergency generator storage facilities and fire fighting pumps, as appropriate.
6.2.4
Oil tanks
6.2.4.1
Fuel oil and light oil tanks The light and fuel oil tanks shall be of the self supporting fixed roof type, designed, constructed, tested and painted in accordance with API standard 650 and the supplemental requirements of this Specification. The storage tanks shall each be enclosed in a concrete wall type bund with a containment volume, which complies with the requirements of the NFPA relating to oil storage. The tanks shall be complete with stairs, handrails (to stairs and roof), internal and external coatings, instruments (level indication and high level alarm, 6.2-5 KHABAT TPP UNITS 1&2 - VOLUME I
displayed locally and on the PCS), vents, manholes, drains, filling and extraction pipework, and any other equipment necessary for the safe operation of the distillate and heavy fuel oil systems. Design of the tanks shall take into account the loadings from various equipment, platforms, fire protection piping and equipment, ladders and stairways, personnel, interior coatings, wind, and earthquake as specified herein. All walking and working surfaces shall comply with applicable standards. Tanks shall be vented during filling, and any excess oil from any venting operations shall be collected and suitably disposed of. All safety interlocks to prevent overfilling of the fuel oil tanks shall be provided including High and High High alarms of the tanks to automatically stop the tanker unloading pumps to prevent tank overfilling. A float level indicator (contents gauge) suitable for observation from ground level, calibrated in liters, complete with remote level indicator, high and low level alarm switches, is required for providing an indication of the quantity of fuel in each oil storage tank. Floats, guide wires, tensioning eyes and bolts for fitting inside the tanks together with outside level indicator, counterweight, counterweight guides, connecting wires, pulleys, brackets and seals where wires pass through the tank roof shall be supplied. The remote tank level indicator shall be arranged to provide a readout of tank contents in the control room. Corrosion allowance for the tank roof, shell and bottom plates shall be a minimum of 1.5 mm. A minimum of [one(1)] light oil storage tank, [two (2)] fuel oil storage tanks and [one(1)] fuel oil emergency storage tank shall be provided.
Emissions of volatile organic compounds from the fuel oil tanks shall be limited by installation of appropriate VOC removal plant, such as active carbon filters. 6.2.4.2 Pressure accumulators Pressure accumulators shall be provided by the Bidder, if considered 6.2-6 KHABAT TPP UNITS 1&2 - VOLUME I
necessary to maintain fuel oil supply pressure during a switch from a duty to standby pump. The pressure accumulators shall be located in the pump discharge header, and shall be designed for operation under all possible operating combinations of pumps. 6.2.4.3 Fuel storage capacity The required storage tank capacity of all fuels shall be as following. - Fuel oil storage tank A and B : 7,000m3 - Residue oil emergency storage tank : 4,000m3 - Light oil storage tank : 500m3 6.2.4.4 Fuel oil pipework, valves and fittings All fuel oil pipework shall be designed, constructed, installed and tested in accordance with ANSI B31.3 or equivalent internationally recognized standards. All buried fuel oil pipework shall be accommodated in trenches which are excavated, prepared and backfilled in accordance with internationally recognized codes and standards ; the depth of cover over the crown of the pipe shall be not less than 900 mm. All isolating valves in the fuel oil systems shall be of the non-lubricated ball type with Teflon seals and resilient faces, where applicable. The valves shall be of the fire-safe design. Threaded valves shall only be used where required for equipment compatibility. Cast iron valves shall not be used for oil service. All piping and equipment shall be protected against excess pressure utilizing pressure relief valves. Over pressurization of blocked or isolated pipelines and equipment by solar heating and ambient temperature changes shall be considered in the design. Relief valve discharge shall be piped to the return header or pump suction, as required. Vents and drains equipped with a ball valve shall be provided at strainers and all high points and low points respectively. In addition, connections required for periodic tests shall be equipped with valves and threaded nipples which shall be protected by threaded caps.
6.2-7 KHABAT TPP UNITS 1&2 - VOLUME I
6.2.4.5 Pressure accumulators Pressure accumulators shall be provided by the Bidder, if considered necessary to maintain fuel oil supply pressure during a switch from a duty to standby pump. The pressure accumulators shall be located in the pump discharge header, and shall be designed for operation under all possible operating combinations of pumps. 6.2.4.6 Thermal insulation The piping and equipment of fuel oil shall be insulated and traced heat and the insulation shall be lagged. Insulation shall be asbestos free and shall be suitable for the service in each location of the installation. The outside surface temperature of the lagged insulation shall not exceed the ambient air temperature by more than 30℃ ambient air velocity of 15 m/min for indoor equipment and 1 m/s for outdoor equipment. Ambient air temperature for the design of thermal insulation shall be 30℃. Lagging for piping and equipment insulation shall be of aluminum alloy 3003 or 3005, minimum thickness of 0.5 ㎜ and fastened with stainless steel bands. Thermal insulation on pipe and equipment shall be calcium silicate or mineral fiber block type insulation complete with aluminum outer lagging. Heat tracing for the piping and equipment of fuel oil shall be furnished by the Bidder. All insulation which is normally removed during routine inspection shall be of the reusable type. The Bidder shall describe the method of preventing detachment of lagging plate in stormy weather.
6.2.5
Steam cconverter system
6.2.5.1 General Steam converter system shall be designed to supply sufficient heating steam for two(2) fuel oil storage tanks suction and bottom heaters, one(1) fuel oil emergency storage tank bottom heater and suction heater, fuel oil heaters. 6.2.5.2 Steam converter
6.2-8 KHABAT TPP UNITS 1&2 - VOLUME I
A.
The steam converter and appurtenances shall be designed in accordance with the requirements of the HEI(Heat Exchange Institute) code and this specification including ASME Section Ⅷ. The steam converter shall be stamped, certified, and documented in accordance with the code. The steam converter assembly shall be designed to withstand loads imposed by fluid pressure, thermal expansion, and piping reaction. Stress resulting from static and dynamic loads, individually and together, shall be within code-specified allowable limits.
B.
The steam converter shall be designed for full shell side design pressure and temperature with atmospheric pressure on the tube side, and for full tube side design pressure and temperature with atmospheric pressure on the shell side.
C.
Reliability in service and accessibility of all parts (where practicable or specified) for inspection, maintenance, and repair shall be a design objective.
D.
The steam converter shall be of the horizontal shell and U-tube type with removable tube bundle. The steam converter shall be TEMA type AKU. Support saddles and lifting lugs designed in accordance with the requirements of the code shall be provided for the steam converter. Attached piping loads shall be considered in designing shells and support saddles.
E.
Tubes for the steam converter shall be steel A-556. The tubes shall be rolled full depth to the tube sheets. Minimum allowable tube size shall be 15.88mm(5/8") OD, and average wall thickness 20 BWG for U-tube type.
F.
The tubesheets shall be welded to the shell and channels.
G. The channels shall have full size flanged and min. 457mm(18"). I.D circular manways providing complete accessibility to the tube-totubesheet joints. H.
Baffles, tube support plates, and tierods shall be provided in sufficient number and adequately spaced to prevent tube vibration. Impingement plates shall be provided under the shell inlet nozzle to protect the tubes against erosion and to prevent vibration. Bundle entrance and exit areas shall be in accordance with TEMA Class R requirements. The natural frequencies of all unsupported tube spans shall be sufficiently removed from hydrodynamically and system generated fluid pulsations to avoid damaging tube vibrations. 6.2-9 KHABAT TPP UNITS 1&2 - VOLUME I
I.
Shell material shall be steel A-286 and tube sheet shall be steel A-226. A shell corrosion allowance shall be minimum 3.2mm. Other materiel not specified in this specification shall conform to HEI requirements.
J.
Adequately sized venting orifices for removal of noncondensable gases shall be provided. Air vent limiting orifices for heat shall be installed in the external piping.
K.
Vent, drain, and pressure and temperature instrument connections shall be provided as required by TEMA requirements.
L.
All connection nozzles and heat exchanger supports shall be designed to withstand safely, forces and moments imposed by connecting piping in addition to the operation weight of the heat exchangers including insulation.
M. The steam converter shall have an electrical grounding connection. N.
The Bidder shall size a connection and provide a heavy duty thermal relief valve to protect the tube side of the heat exchanger. Valve size, type, and material shall comply with ASME and HEI code requirements.
O. The Bidder shall size connections and provide safety relief valves to protect the shell against tube breakage in accordance with the HEI code. P.
The heat exchanger shall be insulated by the Bidder. Thermal insulation shall be provided.
Q. Integral drain cooling zones shall be designed to allow satisfactory operation with a minimum level variation of condensate in the heater shell for both normal and abnormal conditions. On the heater with integral drain cooler, a separate high level drain outlet bypassing the drain cooler section located in the condensing section of the heater shell and having at least the same capacity as the normal drain, shall be provided. Separate and independent level-sensing instrumentation connections shall be provided for normal level, high level and emergency high level. The normal heater drain outlet from the drain cooling section shall be sized for the drain flow that occurs with maximum tube side flow. R.
The maximum water velocity through the tube shall be in accordance with the Heat Exchange Institute Standard at the normal full load operating conditions and shall not exceed 3 m/sec(10 ft/sec).
6.2-10 KHABAT TPP UNITS 1&2 - VOLUME I
S.
The steam converter shall be designed to ensure continuous, safe and economical operation providing the maximum reliability at any operating conditions of temperature changes.
T.
Supports for the steam converter shall be capable of with standing the loads and moments calculated by the Bidder in addition to normal loads and moments, and shall provide for transfer of loads to building structure by positive means.
6.2.5.3
Steam converter feed pumps A.
The pumps shall be inherently stable when running together in parallel at all loads. The feed pumps shall be motor driven with coupling and the water flow to the steam converter shall be controlled by the control valves and the constant speed of the pumps.
B.
The pumps shall be horizontal, centrifugal, diffuser or volute type, with impellers arranged in series specially designed for feedwater pumping service.
C.
Pumps shall be of a design and construction that has been proved reliable
and
satisfactory
for
continuous
operation.
Design
and
workmanslip shall be such that the pumps are readily assembled or dismantled, and they will operate satisfactorily under all operating conditions without undue wear, vibration, cavitation or overheating. D.
Each pump shall be provided with isolating valves on the suction and discharge sides, and also a non-return valve on the pump discharge. Each pump suction shall be provided with a strainer and differential switch. The pumps shall also be provided with separated arrangements to automatically recirculate water back to the steam converter condensate return tank for protection of pumps at low and no load conditions.
E.
The characteristics of the pumps must be such that the shut off head is not greater than 120% of the duty point head.
F.
The flow from each pump is monitored, and a minimum flow recirculation valve is opened to maintain flow above that pumps minimum flow requirements. During normal flow conditions the recirculation valve is closed.
6.2.5.4
Steam converter feed tank, drain receiver tank and blowdown tank
6.2-11 KHABAT TPP UNITS 1&2 - VOLUME I
A.
Steam converter feed tank, drain receiver tank and blowdown tank shall be designed, fabricated, examined, inspected, and constructed in accordance with the ASME Code Sec. VIII.
B.
All the inlet impingement baffles and their supports shall be designed to withstand all forces resulting fron an occasional water slug.
C.
All necessary manholes and access doors for the tanks shall be provided.
D.
The tank drains shall be located to flush with the bottom of tank so that complete drainage can be assured.
6.2-12 KHABAT TPP UNITS 1&2 - VOLUME I
6.3
Electrostatic Precipitator
6.3.1
System description The electrostatic precipitator shall be a cold side flue gas electrostatic precipitator, capable of removing the particulate matter from the flue gas discharge of steam generator. The cold side electrostatic precipitator will be located between the airpreheater outlet and the combined induced draft fan(CIDF) inlet. After passing through the precipitator the gas will be induced to the combined induced draft fan.
6.3.2
System design criteria
6.3.2.1
The electrostatic precipitator shall be designed based on the fuel oil an specified Vol. 3 Schedule A and guaranteed to operate at the flue gas flow rate, flue gas temperature, particulate inlet loading and outlet load ing.
6.3.2.2 Precipitator of each steam generator shall consist of two(2) 50 % precipitators. Each precipitator shall be divided into equally sized chambers. 6.3.2.3 The precipitator shall be sectionalized into fields for ease and flexibility of operation. Each section shall be provided with its own power supply. 6.3.2.4 The precipitator aspect ratio shall be at least 1.0 and maximum gas velocity between collecting electrodes to be limited to 1.2 meter per second. The flue gas conditioning system, if required, shall be a complete and operable system. 6.3.2.5 The precipitator shall be so designed that the guaranteed performance can be continuously sustained on a year-round basis without undue maintenance under any condition of normal operation of steam generator. 6.3.2.6 Design shall apply lubrite or teflon plates or approved equal at those supports where movement due to thermal expansion occurs. The precipitator shall be capable of start-up form a clod condition simultaneously with start-up of the steam generator. The Bidder shall arrange the electrical equipment and control accessories of the precipitator for each unit, in two(2) 50 percent independent interleaved groups.
6.3-1 KHABAT TPP UNITS 1&2 - VOLUME I
6.3.2.7 The precipitator shall be sized and designed so that under any operating condition the outlet particulate loading will not exceed the specified guaranteed limits. Compliance with this guarantee shall be demonstrated through actual field testing. 6.3.2.8 Design flue gas temperature shall apply actual flue gas temperature plus 22 degree C. 6.3.3
Design and construction features The electrostatic precipitator shall be of rigid frame type. All flanges, bolt size, holes, studs, threads, connectors, electric lugs and cable connectors shall be in conformance with ANSI standards. Design temperature for structural design shall be 260 degree C for continuous operation and 400 degree C for thirty (30) minutes for transient condition.
6.3.3.1 Casing A. The precipitator shall be self-supporting above the supporting steel and shall withstand all forces caused by wind, snow or earthquake loads with the internal forces due to pressure, dust load, operating temperature and the dynamic loading imposed by vibrators and rappers. B. The roof of the precipitator shall be designed to support maintenance personnel and tools as well as the loads.
A 1,100 mm high continuous
handrail shall be provided around entire roof. The roof shall be sloped for drainage and protected from accumulation of rainfall. The roof of the precipitator shall be provided with insulation. The finished surface shall also be pitched for drainage. The Bidder shall provide suitable gutter and drain piping terminating 30cm from grade in accordance with the standard plumbing code. Piping shall be fabricated from Schedule 40 carbon steel pipe conforming to ASTM A120 Grade A or B. The insulation shall be covered with 4.5 mm thick seal welded, hot dipped galvanized platform grating for walk-on access to roof mounted equipment. Insulation will be field cut. Cover plates shall be shop cut. The roof cover shall be designed to allow for differential thermal expansion between the cover and the precipitator. Suitable flashing shall be provided at all
6.3-2 KHABAT TPP UNITS 1&2 - VOLUME I
penetrations through the cover. The high voltage insulators shall have heated enclosures. C. Flue gas flow distribution devices shall be designed at the upstream gas duct of EP inlet nozzle by the Bidder. These distribution on devices shall be provided by Bidder, if required. D. The precipitator casing shall be fabricated from low carbon steel plate to ASTM A 36 or equivalent and the wall of the casing shall have a minimum thickness of 6.0 mm. E. The casing shall be of welded construction, except where impractical for access or maintenance. Component sections shall be designed to keep the amount of field welding to a minimum. F. The precipitator shall be designed to withstand the maximum internal transient draft pressure and negative pressure of ± 900 mm H2O at design gas temperature, and adequate provision shall be made for expansion and differential expansion. G. The casing shall be designed to minimize the inward leakage of air or the escape of gas. 6.3.3.2 Ash hoppers A. Hoppers shall be of the inverted pyramidal shape, with a valley angle not less than 55 degrees to horizontal. They shall be fitted with round flanged outlets. The bottom third of each hopper shall have a curved radius transition to facilitate ash flow. B. Hoppers shall have a minimum thickness of 6.0 mm and fabricated ASTM A588 steel plates. The following fly ash densities shall be used in the hopper design : - For volumetric calculation, no settlement
:
150 kg/cu.m
- For structural design and related calculation
: 1000 kg/cu.m
- All hoppers shall be structurally designed for the loads imposed when the hopper is completely filled with fly ash. 6.3-3 KHABAT TPP UNITS 1&2 - VOLUME I
C. Exterior and interior siding for hopper area shall be of minimum 0.55 mm steel sheets, hot dipped galvanized, ASTM A 525, G 90 coating weight or equivalent and with shop coated polyvinylidene fluoride on outside, epoxy primer on inside for insulated metal siding, minimum thickness 25 micron for preventing oxidation and wearing-out and pigment for sun-proof or equal. D. The fly ash hoppers shall be sized so that each hopper shall store all the ash collected in its corresponding part of the precipitator during at least 24 hours of operation at maximum fly ash load using lowest fuel oil without decrease in collection efficiency or increase in draft loss through the unit. Sufficient allowance in capacity shall be made for unequal distribution of ash between front and rear hopper sections. Hopers shall generally not span two(2) electrical fields, but may span two complete electrical fields if adequately baffled to prevent gas flow through the hoppers. E. Each hopper or baffled hopper section shall be equipped with one hopper ash level switch. The level switches shall be operated by fly ash level and be equipped with two(2) DPDT switches for high level. All level switches shall be wired to a subpanel. All level switches shall be designed for high temperature operation. F. The subpanel shall be provided by the Bidder. The subpanel shall have numbered indicating lights for the precipitator hoppers and shall be wired to activate a common alarm. The arrangement of lights shall mimic the precipitator hopper arrangement. G. All hoppers shall be equipped with unbalanced weight type or electromagnetic vibrators and baffle plates, as required, with two(2) 50 mm flanged poke holes located 90 degree C apart with bolt on caps. The electromagnetic vibrators shall be externally mounted on each hopper. Interlocking equipment shall prevent the vibrators from being operated before the fly ash removal system comes into operation. Hopper baffles shall be structurally designed to support a full dust load on one side with the other side completely empty.
6.3-4 KHABAT TPP UNITS 1&2 - VOLUME I
H. All hoppers shall be furnished with steam heating system. The heaters shall be automatically controlled. The heaters shall be sized and located to maintain the temperature of the entire inside face of the hopper plates above 120 degree C under all operating conditions. In addition the heaters shall be capable of heating the entire inside face of the hopper plates to a temperature of 70 degree C above ambient from a cold start in four(4) hours. I. The hopper insulation shall be applied in panels designed for quick removal and replacement. 6.3.3.3 Penthouse Penthouse shall be provided to protect equipment from inclement weather. The heated purge air shall be supplied. Stand-by heated purge air blower per E.P shall be provided. 6.3.3.4 Distribution devices There shall be one or two gas distribution plates or equivalent gas distribution devices at the inlet and outlet of each chamber. The type of plated or device shall completely cover the entire width or each chamber. The design and positioning of the gas flow distribution device shall be in accordance with the results of the gas flow model study. Plates shall be equipped with rappers as necessary to keep them clean. 6.3.3.5 Collecting and discharge electrodes A. Collecting plates shall be of at least 1.2 mm thickness and fabricated ASTM A 366 or equivalent steel plate, The collecting surface shall be free of kinks or excessive “oil canning". B. Plate to electrode alignment shall be per the following table ; - 250 mm(10 in)
± 4.0 mm(± 3/16 in.)
- 275 mm(11 in)
± 8.0 mm(± 5/16 in.)
- 300 mm(12 in)
± 9.6 mm(± 3/8 in.)
- 400 mm(16 in)
±15.9 mm(± 5/8 in.)
6.3-5 KHABAT TPP UNITS 1&2 - VOLUME I
C. Plate spacing shall be between 250 mm(10″) and 400 mm(12″). Electrode design shall prevent oscillation due to electromotive forces, flue gas velocity and rapping accelerations. D. Discharge electrodes shall be of at least 1.6 mm thickness and fabricated corrosion resistance low alloy steel(CRLS) rigid frame type. 6.3.3.6 Rapping system A rapping system shall be provided for cleaning electrodes and collecting plates. As a minimum, system shall be capable of a 100g acceleration normal to the remotest section of the plates. Rapper controls shall be readily adjustable for frequency, and shall be independently adjustable for each electrical field.
All electrical parts of the
rapping system shall be out of the gas stream or protected therefrom. 6.3.3.7 Water washing facilities The Bidder shall furnish a complete automatic water washing system, NaOH mixing tank and injection facilities which will be used to wash the dust and ash from the electrodes when the unit is shutdown. 6.3.3.8
Discharge electrode supporting insulator The insulator shall have sufficient electrical and mechanical strength, and shall be suitable for the high temperature and humidity conditions. Particular attention shall be paid to the method of supporting the electrode with reference to strength, maintenance and performance stability.
6.3.3.9
Insulator chamber Insulator chamber shall be provided with a hot air ventilation system to prevent insulator breakdown. This system shall be complete with electric air heater, purge air fan with motor, inlet filter and distribution pipes. A thermometer with adjustable contacts shall be installed in the ductwork for high and low temperature alarms due to fan failure or heater failure. Each insulator shall be equipped with electric heating to ensure that the temperature at the insulator will not be below the dew point when the plant is started up from a cold state.
6.3-6 KHABAT TPP UNITS 1&2 - VOLUME I
6.3.3.10 Provisions for access and maintenance A. Adequate access for all necessary maintenance activities, inspection, repair and testing shall be provided from the ground level to the roof stairs, ladders and handrails. B. This shall include access platforms to all equipment, ducting, access doors, inspection doors, instrument connections and test connections in accordance with ASME PTC-38 test requirements. C. Access doors shall be provided in the roof of the precipitator and each precipitator hopper or casing. D. A hoisting facility to be supported from the roof of the precipitator, capable of removing each transformer-rectifier unit to grade, shall be provided. 6.3.3.11 Steel structures, stairs and walkway A. The Bidder shall design all structural and miscellaneous steel in accordance with the AISC steel specification or equivalent applicable local building codes. B. Structural steel and appurtenant materials shall conform to ASTM A36 or other higher strength steels. C. The supporting structure shall be of sufficient rigidity and strength so as to avoid undue vibration or undue deflection due to wind or operation of the equipment. The top bearing surfaces of base plates shall be true plane surfaces with all burrs or beads removed. They shall be scribed and centerpunched and provided with leveling nuts and grout holes. Curb plates and angles shall be shop attached to supporting steel whenever practicable. Filler and spice plates shall have full surface contact, with all beads and burrs removed. Walkways and stairs shall be installed on the left and right sides of the EP each stairs shall be complete from ground floor to the top of precipitator. Walkways and stairs shall be provided for all access doors. 6.3.3.12 Thermal insulation The entire precipitator unit shall be insulated and the insulation shall be lagged. Roof insulation covering shall be waterproof and self-draining without
6.3-7 KHABAT TPP UNITS 1&2 - VOLUME I
moisture pockets. Insulation shall be asbestos free and shall be suitable for the service in each location of the installation. All material shall be suitable for the highest temperature and the most severe service to which they shall be subjected, including the effects of vibration. All insulation materials and all associated binders, sealers, barrier sheets, finishes and attachments shall be noncombustible. All insulation which is normally removed during routine inspection shall be of the reusable type. The Bidder shall describe the method of preventing detachment of lagging plate in stormy weather. The insulation shall be designed and installed to minimize the convection current in the space between the hot metal surface and the inner layer of the insulation. 6.3.3.13 Electrical requirements The Bidder shall engineer, design and furnish completely all electrical equipment and accessories required for the operation of the electrostatic precipitator system and the Bidder shall design electrostatic precipitator(EP) equipment with minimum power consumption. A. Transformer-Rectifier Transformer-rectifier sets shall be of silicon type. The transformer- rectifier shall be adequately surge-protected and be of the oil immersed self-cooled type. B. High Voltage Ties The Bidder shall furnish the high voltage water tight metal clad bus connections between the rectifiers and the precipitator electrodes shall be grounded. C. The Bidder shall provide the all motors, heaters and accessories. 6.3.3.14 Instrumentation and control A. General a) The Bidder shall furnish a complete package of instrumentation and controls necessary to meet the requirements of this specification, and that shall offer a high degree of reliability and safety to both personnel and apparatus. 6.3-8 KHABAT TPP UNITS 1&2 - VOLUME I
b) PLC based control cubicles and complete field instrumentation for the automatically precipitator controls and monitoring shall be provided. c) Minimum one(1) operator interface station with dual LCD monitors(min. 21 inch) and printer per one(1) generating unit shall be provided. d) The EP control system shall be designed to enable the operator to supervise and operate the electrostatic precipitator system by using LCD/keyboard in local control room. e) EP control system shall be provided with the data communication interface devices with PCS for the supervisory control and monitoring in the central control room. g) The PLC shall be provided with redundant (hot back-up) CPUs, power supplies and data communication networks. f) Instrumentation and controls shall be designed in accordance with the section 8 of this technical specification unless otherwise specified in this section. g) The dust concentration monitoring system including dust analyzers shall be provided for the efficiency calculation and energy management of EP. Dust analyzers shall be installed each EP inlet duct and outlet duct and shall be used for precipitator control.
6.3-9 KHABAT TPP UNITS 1&2 - VOLUME I
6.4
Ash Handling System
6.4.1
General A.
The Bidder shall supply all equipment and piping, Ash storage silo support steel, pipes and equipment shall be shop assembled, match marked to facilitate field erection and slipped knocked down in the largest possible sections.
B.
The fly ash is collected at the EP hopper and transported to ash storage silo by vacuum system.
C.
The stored ash is dehumidified through the discharge gate damper rotary feeder, dustless unloader and unloaded into bag.
D.
The ash handling rate is designed to evacuate the ash within the two(2) hour that produced in an eight(8) hour shift at EP design condition of the BMCR. and ash is un loaded into container by using the rotary feeder/dustless unloader for truck trans port.
6.4.2
Design and construction features
6.4.2.1 Ash transfer system A.
The steam air heater shall be supplied to obtain the adequate hot air for preventing from ash plugging and corrosion problems in the ash piping.
B.
Seal air blower shall be supplied to prevent dust and corrosive gas from coming down into transport pipe, when dust transportation is rest and boiler shutdown.
C.
Angle type
plate shut-off valve is pneumatically operated to obtain
adequate vacuum, pre-warming and after cleaning of ash piping. D.
The flap type non-return valve shall be installed to prevent damage caused by reversal gas flow leakage from the interior of the EP at shutdown of the equipment.
E.
The Bidder shall be supplied following discharge devices. 1) Ball flap valve Nonsliding ball flap valve shall be provided and pneumatically operated. 2) Dust Hopper Dust hoper is provided for temporarily storing the ash collected by the cyclone and/or bag filter. Hot air aeration system is provided for the smooth discharge function of the ash in storage silo. 6.4-1 KHABAT TPP UNITS 1&2 - VOLUME I
3) Equalizer Valve Pneumatically operated ball valve shall be provided for equalizing the pressure between the transport pipe side and ash storage side. 6.4.2.2 Vacuum pump A.
The Bidder shall furnish two(2) 100 % Water Ring type vacuum pumps including the drivers.
B.
Each
pump
consists
of
water
sealing system and air-water
separator which have the function of silencer and gas cleaner. C.
Vacuum breaker shall be provided to prevent excessive torque at the time the vacuum pump is started and prevent plugging.
6.4.2.3 Bag filter A.
A bag filter shall be provided to separate ash from conveying stream into silo. Air to cloth ratio of bag filter shall be 0.67:1 Acu.m/min./sq.m (2.2:1 Acfm/sq.ft) if filters shall be compartmentalized so that
half of the filter is
taken out of service for maintenance, and acceptable air to cloth ratio of 1.34:1 (4.4:1) is still maintained without interrupting operation. B.
The bag filter shall have a collection efficiency of at least 99.5 % of all in fluent dust and shall be supplied with all complete accessories required for filter operation.
C.
The bag filter shall be provided with a complete system for overtemperature protection, including temperature probe and ambient air pulse valve.
D.
Automatic regeneration provision in bag filter shall be provided. Pulse air is used as the regeneration medium.
6.4.2.4 Ash storage silo A.
The ash storage silo shall be cylindrical, bottom supported, and fabricated structural grade carbon steel plate, of welded water and gas tight construction throughout. The silo shall be shop-assembled, match marked to facilitate field erection, and slipped knocked-down in the largest possible sections consistent with correct shipping practice.
B.
The net volume of the silo shall be based on storing material for a minimum of 72 hours.
6.4-2 KHABAT TPP UNITS 1&2 - VOLUME I
C.
The cylinder shall be fabricated from ASTM A 36 or equivalent steel plate, 6 mm thick minimum.
D.
The ash storage silo and support structures shall be complete with all auxiliary equipment including level indicators, vacuum relief valves, access door, electric vibrator and all necessary valves and controls.
E.
All structural steel for the support of the ash storage silo shall be provided along with all stairways, ladders, platforms, handrails and other equipment required for access. In areas were designated access for trucks and maintenance equipment, the minimum elevation shall be 3.5 m from ground to bottom of ash storage silo.
F.
The ash storage silo shall be furnished with steam heating system. The heaters shall be automatically controlled. The heaters shall be sized and located to maintain the temperature of the entire inside face of the hopper plates above 120 degree C under all operating conditions. In addition the heaters shall be capable of heating the entire inside face of the hopper plates to a temperature of 70 degree C above ambient from a cold start in four(4) hours.
G. The
ash
storage silo
unloading area shall be totally enclosed with
ventilating units to prevent dust emission. 6.4.2.5 Rotary feeder The Bidder shall be furnished Rotary Feeder to supply a constant volume of dust from ash storage silo to the dustless unloader by causing the action of a loader with vanes that rotate within the casing. The heaters shall be fabricated corrosion resistant low alloy steel. Sealing air is injected to prevent intrusion of the dust into the bearings. 6.4.2.6 Dustless unloader The dust transported by the rotary feeder moves towards the outlet while being water-sprayed and kneaded through vanes attached to the shaft. Dual shaft type unloader shall be provided with a gland seal and sealing air to prevent the dust form intruding into the bearings. 6.4.2.7 Ash transport pipe A.
Ash transport pipe shall be coated with special aluminium to prevent corrosion. 6.4-3 KHABAT TPP UNITS 1&2 - VOLUME I
B.
The expansion and contraction of the ash transport pipe at the lower part of the electrostatic precipitator hopper are absorbed through coupling or expansion joint.
C.
The piping from the outlet of steam air heater to the inlet of bag filter is steam traced
6.4.2.8 Instrumentation and controls A.
The Bidder shall furnish a complete package of instrumentation and controls necessary to meet the requirements of this specification, and that shall offer a high degree of reliability and safety to both personnel and apparatus.
B.
PLC based control system and complete field instrumentation for the automatically ash handling system controls and monitoring shall be provided.
C.
Minimum one(1) operator interface station with dual LCD monitors(min. 21 inch) and printer per one(1) generating unit shall be provided.
D.
The ash handling control system shall be designed to enable the operator to supervise and operate this system by using LCD/keyboard in local control room.
E.
The ash handling control system shall be provided with the data communication interface devices with PCS for the supervisory control and monitoring in the central control room.
F.
The PLC shall be provided with redundant (hot back-up) CPUs, power supplies and data communication networks.
G. Instrumentation and controls shall be designed in accordance with the section 8 of this technical specification unless otherwise specified in this section.
6.4-4 KHABAT TPP UNITS 1&2 - VOLUME I
6.5
Steam Turbines and Auxiliaries
6.5.1
Conditions of service
6.5.1.1 Description of service The steam turbine-generator will receive steam from oil fired, drum type steam generator for the generation of electric power. Each unit will operate in parallel with other station generating units within the MOE power system. The turbinegenerator unit may be subjected to sudden load rejection or rapid load pickup, and to adverse conditions due to maladjusted unit controls. The steam turbine-generator shall conform to the design and arrangement indicated on the drawings and requirements specified in the specification. 6.5.2
Design conditions
6.5.2.1 Type of steam turbine-generator A. The steam turbine-generator shall be of standard design condensing, tandem compound, single reheat steam turbine with 3000 rpm synchronous generator. B. The turbine shall be capable of operation both partial arc admission and on full arc admission. The turbine and control valves shall be capable of operation on constant pressure with the control valves operating sequentially.
In addition, the control valves should be capable of being
held at a position which offers the most desirable heat rate or advantageous operating condition. C. The turbine low pressure ends shall be arranged for bottom or axial exhaust and provided with an outlet for a bolted flange or welded connection to a condenser expansion joint. 6.5.2.2 Steam extractions and feedwater heating cycle The turbine-generator nominal rating and valve wide open rating shall be based upon a regenerative feedwater heating cycle with all heaters in service. Any extractions for operating auxiliaries and air heating purposes to be returned to the cycle will be returned to the main condenser. 6.5.2.3 Operating speed and allowable vibration
6.5-1 KHABAT TPP UNITS 1&2 - VOLUME I
A.
The turbine-generator unit at the rated speed of 3000 rpm shall not exceed the vibration and shaft movements specified hereinafter. The maximum vibration as measured on the turbine and generator shafts adjacent to all bearings shall not exceed 80 microns double amplitude throughout the load range. The maximum vibration as measured on the turbine and generator bearing pedestals will not exceed 4.5 mm/sec throughout the load range. Shaft movement in either axial direction shall not exceed 0.9 mm when measured from the center of the thrust cage clearance.
B.
The turbine-generator shall also be capable of operation at any speed above the rated speed up to 110 percent of the rated speed without exceeding the above specified maximum vibration and without showing any sign of stress or instability.
The unit shall be sufficiently strong to
withstand, without damage, any stresses or deflections that might result from transient speed up to 120 percent of the rated speed. 6.5.2.4 LP Bypass system capacity The turbine LP bypass system capacity shall be based on the following requirements ; A.
The times required for startup, loading and unloading shall be at the minimum values attainable.
B.
The bypass system capacity shall not increase the size of main condenser more than that required by a normal design without considering bypass system.
C.
The steam turbine shall be capable of withstanding 100% load rejection without an overspeed trip.
6.5.2.5 Allowable metal temperatures The Bidder shall describe in the proposal the maximum rate of change in allowable metal temperatures of HP turbine first stage and IP turbine bowl for the various load changing mode of cold start, warm start, hot start and restart 6.5.2.6
Performance condition and heat balances The Bidder shall state and satisfy for the steam cycle considered, the following performance of the steam turbine-generator according to design conditions All of the performance values shall be achieved without any measuring
6.5-2 KHABAT TPP UNITS 1&2 - VOLUME I
tolerance, i.e. uncertainty. The KNOC will not accept any deviations and exceptions for the entire paragraph A.
Performance Conditions 1) Performamce output at MGR 2) Turbine heat rate at MGR 3) Time required in minutes from steam to turbine to MGR for warm start 4) Rated generator capacity at 0.85 power factor. 5) Minimum stable load under full automatic control 6) Auxiliary Power at MGR
B.
Heat Balances The Bidder shall furnish the following ; 1) A heat rate curve over the full operating range which will show the effect of throttling. 2) Performamce heat balances at MGR 3) Calculated heat balances for the cases as follows ; a) VWO b) CR c) MGR with High Back Pressure d) MGR with Low Back Pressure c) 75% load of MGR d) 50% load of MGR e) 30% load of MGR f) MCR & THO rating g) House load 4) A thermal kit corresponding to the heat balances including the curves and data described in "Schedule C2." The correction equations and the application criteria shall be included in all correction curve drawings.
C.
Heat Balance Basis Heat balances shall be based on the following requirements ; 1) Final feedwater temperature shall be optimized at MGR condition.
6.5-3 KHABAT TPP UNITS 1&2 - VOLUME I
2) In
the
heat
balance
diagrams,
no
less
than
two
thermal
properties(pressure & temperature or pressure & enthalpy) shall be shown at any point where flow functions are described. 3) Condensate leaving the condenser hotwell shall be at the saturation temperature corresponding to the turbine exhaust pressure. 4) Properties of steam shall be in accordance with IF97 SI Steam Tables. 5) The main feed pump discharge pressure shall no less than 1.25 times the throttle steam pressure. 6) In all heat balances, the boiler feed pump shall be modeled to be driven by motor. 7) Compressed liquid values shall be used in determining the enthalpy of feedwater at any point after it leaves the main feed pump discharge. 8) All heat balances up to 30% MGR shall be predicated on No. 5 HP heater drain to deaerator. 9) Heat balances shall show turbine stage pressures and enthalpies at bleed steam extractions and first stage shell. The pressures at the extraction nozzles shall be shown where internal pressure drop occurs between turbine stage and extraction nozzle outlet. 10) Heat balances shall show the pressures and enthalpies at the downstream of bleed steam extractions such as heater inlet. 11) Heat balances shall show the ELEP, UEEP and vacuum at the condenser and the enthalpy and vacuum at feed pump turbine exhaust. 12) The throttle losses of main steam and control valve, reheat steam stop and control valve shall be shown. 13) Heat balances shall show turbine wheel power, fixed mechanical loss, generator loss, gear box loss (if installed) and generator terminal output. 14) The losses of generator and the power consumption of excitation shall be respectively shown on heat balance diagram. The heat balance shall be calculated and prepared on the basis of the generator output including the excitation power consumption. The following two heat rate shall be calculated and shown on heat balance diagram. 6.5-4 KHABAT TPP UNITS 1&2 - VOLUME I
15) Gross heat rate based on the generator output including the excitation power consumption. 16) Gross heat rate based on the generator output except for the excitation power consumption. 17) Mechanical vacuum pumps will be used to evacuate air and noncondensable gases from the main condenser. 18) Turbine-generator heat rate shall be calculated as follows ; GHR = [M1xH1 - M2xH2 + M3xH3 - M4xH4 - MixHi + MjxHj - MsxHs - MrxHr]/ [KWG] Where ; GHR : turbine-generator gross heat rate, kcal/kWh KWG : generator terminal net electrical output, kW M H
: flow of steam, feedwater, or drain, kg/h : enthalpy of steam, feedwater, or drain, kcal/kg
Affix to M and H ; 1
: throttle steam at stop valve inlet
2
: feedwater at boiler inlet
3
: steam leaving reheater
4
: steam entering reheater
i
: bleed auxiliary steam, and leakage
j
: drain of auxiliary steam returning to cycle, and makeup
s
: superheater spray water
r
: reheater spray water
※ It is needed to achieve steady state conditions during the test. 19) The values of the following steam properties shall be ;
6.5-5 KHABAT TPP UNITS 1&2 - VOLUME I
- pressure : rounded off to two decimal places, but LP Turbine, LP Heater and its piping pressure shall be rounded off to three decimal places - temperature, enthalpy and heat rate : rounded off to two decimal places 20) The Bidder shall provide the heat balance diagrams prepared in MKS and SI unit system. The major units or these system are as follows ;
6.5.3
MKS unit system
: kg/h, kg/cm2, kcal/kg, ˚C, kcal/kWh
SI unit system
: kg/h, bar, kJ/kg, ˚C, kJ/kWh
Design features for turbine
6.5.3.1 General The turbines shall be designed throughout so as to insure continuous, safe and economical operation providing the maximum of reliability and without undue heating, vibration or noise. The turbines shall be located indoor in slide along arrangement.
The turbine rotors shall be designed to prevent axial
movement during abnormal operating conditions. 6.5.3.2 Blading All blading shall be of proven design and shall be free of harmful resonant behaviour in the normal operating speed range of synchronous speed +/- 10%. The design of blade and its root fixing as well as the material of construction shall have been used in similar applications and at similar operating conditions for a period of not less than 3 years commercial operation without serious incident. Integral shrouding is preferred. Blading material and design shall be selected with regard to the operating conditions during all normal operation at full load and part load. 6.5.3.3 Casing The casing shall be drilled for temperature elements to indicate first stage shell temperatures, valve chest metal temperatures, etc. The main horizontal and vertical joints in the turbine shell shall be metal-to-metal.
Provisions
6.5-6 KHABAT TPP UNITS 1&2 - VOLUME I
such as manhole shall be provided on each IP/LP casing for inspection of IP/LP buckets without opening of the turbine casings. 6.5.3.4 Bearings and seals A.
All turbine-generator main shaft bearings shall be provided with seals to control oil and vapor leakage along the shaft. Bearings shall be of the self-aligning type and split to permit removal of the upper half for inspection.
Bearings shall be accessible for inspection without removal
of the turbine shells.
Each main shaft bearing shall be equipped with a
temperature element imbedded in each main bearing. In addition, temperature detecting sensors shall be located in all main bearing drains. B.
Each thrust bearing shall be equipped with temperature elements located in each front and back thrust bearing plate or shoe to provide for indication of excessive thrust bearing temperature. Electronic thrust bearing wear detectors for sensing thrust bearing position shall be provided and shall activate automatic tripping of the turbine in case of excessive thrust bearing wear.
6.5.3.5 Couplings The couplings connecting the turbine and generator and the various turbine shafts shall be of a type that can be readily disconnected for purposes of inspection and repair. 6.5.3.6 Serviceability of parts All parts of the turbine shall be accessible and capable of ready removal, assembly or replacement. Upper casing and main bearing caps shall be provided with lifting lugs or eyes. 6.5.3.7 Drainage All interior recesses in the turbine in which condensate may be pocketed shall be designed for adequate drainage. 6.5.3.8 Sound enclosures The Sound Enclosures over the turbine-generator shall be suitable for indoor operation. It shall cover all major turbine-generator part with complete auxiliary equipment such as ventilation and lighting system, etc. It shall be easy to disassemble and assemble during routine overhaul activities.
6.5-7 KHABAT TPP UNITS 1&2 - VOLUME I
6.5.3.9 Leakage When the steam generators are in the hydrostatic test condition, it will be necessary to load the main steam leads with water in excess of normal operating pressure. Leakage through stop valves shall be zero during these conditions. Construction of steam passages shall be such that small quantities of water which may leak through stop valves incidental to starting the unit will be diverted to drains. The combination of stop valves and draining shall preclude the possibility of water getting into the turbine. The Bidder shall provide all special devices and equipment to assure protection of the turbine generator set during hydrostatic test. 6.5.3.10 Pressure connections No pressure connections, valves, or cylinders containing flammable oil or fluid shall be used on turbine valves above steam pipes or hot surfaces. 6.5.3.11 Packings The packings shall be steam throttling device consisting of stationary and rotating teeth arranged concentrically with small radial clearances. The effectiveness of the packing to minimize leakage shall be dependent upon the sustained radial clearance between the packing teeth and the rotor. 6.5.4
Steam contamination
6.5.4.1 Contamination The steam for the operation of the turbine may contain small quantities of volatile, alkaline materials originating from ammonia or volatile amines and hydrazine introduced to the feedwater system for corrosion control. Steam contamination may occur as an end result of condenser circulating water inleakage and as a result of corrosion products from the feedwater system and boiler. 6.5.4.2 Materials The Bidder shall provide turbine materials which are most suitable for the service and which shall be resistant to corrosive attack from steam contaminants originating from the above sources, and shall be based on a plant operating life. 6.5.5
Erosion prevention 6.5-8 KHABAT TPP UNITS 1&2 - VOLUME I
The turbine shall be designed to minimize as far as possible the erosive effect of moisture in the steam and of water upon those parts of the turbine subject to their action. The material as well as configuration of stationary and moving blades selection shall be such as to minimize erosion from steam generator tube scaling. The Bidder shall describe his technique for moisture removal and erosion controls. 6.5.6
Turbine stop and control valve systems The turbine inlet valves shall be fast-closing hydraulically actuated type of established design. The inlet stop valves shall be designed for tight shut off. All main inlet and control valves shall be provided with facilities for on-load testing. The stop valves shall be fitted with permanent steam strainers designed as an integral part of the turbine stop valves. The strainers shall prevent the passage of foreign objects larger than [3] mm.
6.5.6.1 Main stop valve A.
Hydraulically operated stop valve shall be provided in the main steam lead and shall be capable of being tripped automatically during overspeed or at other predetermined limit points.
B.
The stop valves shall be equipped with an internal bypass valves, if required by design, for chest warming required prior to rolling the turbine. Internal bypass valve controls shall be provided from the Bidder control system via Bidder operator interface in the control room. Stop valve shall be suitable for hydrostatic testing of the steam generator, without requiring stop valve at the steam generator.
6.5.6.2 Reheat stop valves Reheat stop valves shall be designed with provisions for sequential remote testing while the unit is in operation. These valves shall be furnished with valve-travel limit switches (one normally open and one normally closed pairs of contacts at each end of each valve mechanism) per valve for indication of valve position. 6.5.6.3 Steam blowdown cover plates
6.5-9 KHABAT TPP UNITS 1&2 - VOLUME I
One(1) set (common to two(2) units) of temporary steam blowdown cover plates for main steam stop valves, reheat stop valves and HP turbine exhaust non return valves shall be provided. All required gaskets shall be supplied. 6.5.6.4 Steam strainers Each main steam stop valve and reheat stop valve shall be equipped with permanent, integral strainers made of radial flow blade type elements for normal operation. Strainer screens shall be removable without disturbing steam piping. 6.5.6.5 Control valves Multiple speed and load governor-controlled, hydraulically operated turbine control valves.
Provisions for sequential remote testing while turbine is in
operation shall be provided. In addition, linear variable differential transformer(LVDT)s shall be equipped for each control valves. 6.5.6.6 The Bidder shall provide the design requirements of the non-return bleeder trip valves and isolation valves. 6.5.7
Turbine bypass system
6.5.7.1 A complete low pressure bypass system shall be provided by the Bidder. The equipment furnished by the Bidder shall include, but not necessarily be limited to, the following ; A.
Low pressure bypass control valve with emergency quick closing function, its motorized drain valve and piping to the flash tank and necessary appurtenances.
B.
Desuperheating spray water control valve, desuperheaters with orifices and necessary appurtenances.
C.
Pressure and temperature control system to operate the bypass control valves and spray water control valves shall be controlled and monitored in the PCS.
D.
Hydraulic power units and control fluid piping to the actuators. Hydraulic power units shall be operated and monitored on the plant OIS.
E.
Instrumentation to operate the bypass control valves, spray water control valves.
F.
Devices for turbine startup and protection system.
6.5-10 KHABAT TPP UNITS 1&2 - VOLUME I
1) Power operated non-return valves at high pressure turbine exhaust, pre-heating valve, pressure release valves, piping and orifice to the condenser. 2) Instrumentation to operate the power operated non-return valves, preheating valve and pressure release valves. 6.5.7.2 The low pressure bypass system shall be designed for the capacity of 40% of VWO rating of the turbine. The bypass control valves shall be provided with low velocity trim. The low pressure bypass system will dump steam from the hot reheat system into the condenser and be controlled by the pressure in the hot reheat system. Spray water for desuperheating will be supplied from the discharge of the condensate water pump. The bypass control valve shall be positioned by the control systems furnished with the turbine. The servo valve unit for the low pressure bypass valves shall be installed separately from the low pressure valves to prevent damage due to vibration. 6.5.7.3 The high pressure bypass system will be 40% capacity of BMCR(VWO) rating of the boiler. The high pressure bypass system will dump steam from the main steam line into the cold reheat system and be controlled by the pressure in the main steam system. Spray water for desuperheating will be supplied from the boiler feed pump discharge to the spray water control valve. 6.5.7.4 The Bidder shall provide all necessary pressure/ temperature transmitters, smart positioner with transmitters and pressure switches and installation materials etc. 6.5.7.5 The low pressure bypass system shall be controlled and monitored in the PCS. 6.5.7.6 The Bidder shall recommend the detail features to control and monitor the bypass system in the PCS. 6.5.8
Lubricating oil system Complete lubricating oil system including, but not necessarily be limited to, the following shall be provided ;
6.5.8.1 A lube oil reservoir with top mounted relief and access doors and all associated instrumentation and controls specified in paragraph 4.8. The reservoir shall have a capacity equal to the quantity of oil circulated through the system in approximately 6 minutes. The reservoir shall have sufficient 6.5-11 KHABAT TPP UNITS 1&2 - VOLUME I
free volume operating level above the normal range to accommodate full system flowback without bringing in the high level alarm regardless of oil temperature. The Bidder shall furnish and install the following equipment on or close to the lube oil reservoir.. A. Two(2) identical AC motor driven lube oil pumps B.
A DC motor driven emergency bearing oil pump, including the DC motor starter panel. The starter panel shall be equipped remote control function(start/stop etc.) of starter shall be provided in the PCS.
C.
An AC motor driven turbine bearing lift oil pump
D. Two(2) 100% oil coolers for use with closed cooling water at the inlet temperature and pressure of 35oC /10kg/cm2g Oil side of the coolers shall be designed for maximum expected oil pressure. Coolers shall be complete with interconnecting oil piping and manual three-way valve with provisions for safe transfer of oil flow from one cooler to the other. The oil cooler materials shall be selected for resistance to corrosion and erosion and shall be fabricated, assembled and, if necessary, treated with a suitable coating to maintain such resistance. E. Two(2) 100% AC motor driven vapor extractors. F. Thermostatically controlled electric heaters. G. Special return compartment located at oil return to reservoir. H.
Mesh or plate type lube oil demisters.
6.5.8.2 A lube oil conditioner of coalescence type for the conditioning of main turbine lube oil. The oil conditioner capacity shall be enough to circulate 10% of total oil within one(1) hour.
The Bidder shall furnish and install the following
equipment on each oil conditioner. A.
One(1) 100% AC motor driven conditioner recirculation pump.
B.
Filter assembly with instrumentation and other accessories
6.5.8.3 A lube oil storage tank(clean/dirty oil tank, one(1) for four(4) units) with top mounted access doors and all associated instrumentation and controls specified in this specification The storage tank shall be of horizontal, cylindrical type consists of two(2) compartments for clean oil and dirty oil 6.5-12 KHABAT TPP UNITS 1&2 - VOLUME I
storage separated by division wall.
Each compartment of the storage tank
shall have a capacity enough to fill the whole lubrication system including the main turbine oil reservoir, main turbine oil conditioner at a time. Each compartment of the storage tank shall have sufficient capacity to accommodate full system drainage to a compartment of storage tank without bringing in the high level alarm regardless of oil temperature. The Bidder shall furnish and install a thermostatically controlled electric heater at each compartment.
Mesh or plate type lube oil demisters shall be installed
at the vent outlet. 6.5.8.4 Two(2) 100% clean & dirty oil transfer pumps with duplex strainers 6.5.8.5 Complete fire protection system for lube oil system. 6.5.8.6 Complete interconnecting stainless steel oil piping with hangers and supports for the equipment. In order to minimize the risk of fire, oil and steam piping are as far as possible routed separately on different sides of the turbine. Where pressurized oil piping is close to hot parts, protection shields will be provided. 6.5.8.7 The Bidder shall describe the proper measure, between each bearing inlet and main oil reservoir, to prevent damage of bearings resulting from influx of foreign materials that might be contain in the oil. 6.5.8.8 Jacking oil system A jacking oil system shall be provided to facilitate turning of the rotor for cooling down and during maintenance activities. It is preferable that the jacking oil system should only be required to assist starting of the barring motor and that normal barring speed should be high enough to establish hydrodynamic lubrication at the bearings using the main or auxiliary oil pumps. 6.5.8.9 Hydraulic control fluid system The Bidder shall provide complete high pressure hydraulic control fluid system including, but not limited to, the following ; A.
Two(2) AC motor-driven full capacity pumps with totally enclosed fan cooled type motor; one for normal use, the other for standby.
B. Two(2) full-capacity fluid coolers. C.
A Hydraulic accumulator with connection line, valves and gages.
6.5-13 KHABAT TPP UNITS 1&2 - VOLUME I
D. The above equipment shall be mounted on a hydraulic power unit which shall be complete with level indicator, high and low level alarm switches and low level trip, relief valves, filters, and controlled heater and other necessary instruments. E.
Complete system of interconnecting stainless steel piping and stainless steel tubing between the high-pressure fluid supply system and turbinegenerator and auxiliary equipment.
F. Thermometers and temperature detectors in the inlets and outlets of fluid coolers. G. Pressure gages in each pump discharge, relevant points in the hydraulic system, and test points. H.
Pressure switches as required for automatic start of standby oil pump on low fluid pressure with spare contacts.
I.
Fluid transfer and filtering system complete with motor driven transfer pump, filters, and flow controls.
J.
Pressure switches for hydraulic fluid pumps.
K.
Hydraulic fluid reservoir with access doors.
6.5.8.10 Gland steam sealing system A. The turbine shall be provided with steam sealed glands on packings to prevent steam leakage to the atmosphere or air leakage into the turbine. A gland seal regulator shall automatically control steam pressure to the gland seals over the entire load range. If applicable, gland seal steam pressure control shall be covered in the turbine control system. B. The gland exhausting system shall include a surface type seal steam condenser suitable for the inlet condensate temperature and pressure as approved by the KNOC, and two(2) 100% AC motor driven exhausters. C.
All interconnecting piping between the turbine, the gland seal regulator and condenser shall be furnished, including hangers and supports, relief valves, isolation valves, control valves, pressure gauges, strainers, steam traps, orifices, expansion joints, fittings, and instruments necessary for automatic operation of the system.
6.5-14 KHABAT TPP UNITS 1&2 - VOLUME I
D.
During hot startup and warm startup, gland seal steam sources will be cold reheat steam and/or auxiliary steam. If superheating of these steam are required for the operation of gland steam seal system, the Bidder shall provide an electric steam superheater.
E.
Means shall also be provided for manual operation of the gland seal system when the regulator is out of order. Any other devices deemed necessary to properly operate the Bidder system such as blowdown, diverting, or spillover valves shall be provided complete with all accessories.
F.
The drain from gland steam sealing system including gland steam condenser loop seal shall be drained to the condenser.
6.5.8.11 Turning gear An AC motor driven turning gear shall be furnished, complete with oil piping and all associated hangers and valves, and all necessary interlocks to prevent the turning gear from operating until proper oil pressure has been established in the turbine-generator bearings. The turning gear motor shall have provisions for rotating the motor shaft manually to engage the turning gear with the main turbine shaft. The turning gear shall be of automatic engaged and disengaged type with hand turning device. A local turning gear instrumentation, including control switches, indicating lights, speed indicator ammeter and current transformer shall be provided. The rotor turning speed will be 5 rpm or above.
6.5.8.12 Speed reduction gear (if required) The purpose of Speed Reduction Gear Unit is to permit generator and turbines to have different but optimized shaft speed and to transmit power from the turbines to generator. This Unit shall be a single stage parallel shaft gear with two horizontally offset shafts. The standard design of the gear unit is in accordance with AGMA 421.06. Single helical gears shall be used in standard arrangements. Depending on the overall turbine generator configuration, the gear boxes can be equipped with a thrust bearing on the low speed shaft. A.
Casing 6.5-15 KHABAT TPP UNITS 1&2 - VOLUME I
Inspection openings shall be provided to allow for easy inspection of the gears. Provisions for mounting of RTD's, vibration probes and speed transmitters(key-phasors) shall be provided B.
Gearing and shafts The pinion and the wheel shall be manufactured from high alloy, special quality steel and case hardened. The tooth flanks shall be precision ground with lead and profile correction to compensate for torsional and thermal deflections and to guarantee lowest vibration and noise emissions. In certain cases, depending on the tooth load and pitch line velocity, the tooth surface of the pinion will be copper plated. Angular and parallel misalignment shall be compensated by means of flexible shafts. Between the turbine and the gear box there shall be an external quill shaft, and between the gear box and the generator a quill shaft shall be used. The flexible shafts shall be made of forge, high quality tempered steel with solid flanges.
C.
Lubrication The bearings and the gear shall receive oil from the lubrication system through a central connection in the gear casing. The lube oil amount for each bearing and gear mesh shall be optimized in order to obtain the highest efficiency. The lube oil returns to the main oil tank through the oil drain openings in the bottom of the gear casing.
D.
Bearings The gear unit shall be equipped with hydrodynamic journal bearings, which are axially split and white metal lined. Depending on the various conditions of load and velocity and the required stability and damping, cylindrical, lemon bore, offset half, multi-lobe and tilting pad bearings will be used.
6.5-16 KHABAT TPP UNITS 1&2 - VOLUME I
If a thrust bearing is required, the axial forces will be absorbed either by a combined journal and thrust bearing or by a separate selfcontained flange mounted thrust bearing. The thrust bearing shall be designed as tilting pad thrust bearing. The sealings are non-contact, split labyrinth seals. E. Turning gear The Speed Reduction Gear Unit shall be equipped with a AC motor driven turning gear at the free end of the pinion, comprising an electric motor, a speed reduction gear and an overrunning clutch. Before a turbine start, the turning motor is started and the clutch engages automatically. After turning for required time (depending on cold, warm, or hot start), the turbine is started. The clutch disengages when the speed of the pinion exceeds the turning gear speed and the motor stops. At a turbine stop, the turning gear motor starts and the clutch engages automatically as the turbine is coasting down. The turning gear motor shall have provisions for rotating the motor shaft manually to engage the turning gear with the main turbine shaft.
The
turning gear shall be of automatic engaged and disengaged type with hand turning device. Turning gear instrumentation, including control switches, indicating lights, ammeter and current transformer shall be provided and turning gear shall be controlled and monitored by TCMS. The Bidder shall propose the rotor turning speed.
6.5.8.13 Other devices A.
Complete turbine exhaust water spray system for turbine exhaust, including piping with hangers, sensing elements, and water spray control valve with manual bypass valve and isolating valves. These facility shall be provided IP/LP casing hood. The water spray valve shall be an air diaphragm-operated control valve activated by a solenoid air pilot valve. Exhaust hood temperature controller shall be electronic type. (pneumatic controller is not acceptable) If applicable, exhaust hood temperature control shall be covered in the turbine control system. 6.5-17 KHABAT TPP UNITS 1&2 - VOLUME I
B. Vacuum trip function A vacuum trip shall be provided to trip the turbine in the event of the vacuum continuing to fall and reaching a predetermined low value. The vacuum trip is preferably to act directly on the turbine generator protection system to shut the turbine control valves and emergency stop valves. Simultaneously with closure of the steam supply valves, the device is to cause the HV generator circuit breakers to open. Provision shall be made to automatically inhibit the vacuum trip functions to facilitate the run-up of the turbine. The functions shall be arranged to activate themselves as soon as the pre-determined operating limits have been reached C. Turbine exhaust overpressure protection Protection against excessive pressure in the condenser is to be provided by replaceable exhaust rupturing discs or self re-seating diaphragms capable of discharging full load steam flow. The materials used are to be capable of safely withstanding the temperatures reached during prolonged light load running. The discharge from the diaphragms is to be directed outside the turbine building to atmosphere at such a height as to avoid endangering any personnel. The diaphragms are to be suitably designed for the pressure differentials involved and adequately protected against corrosion. 6.5.8.14 Piping A. Turbine Integral Steam Piping (1) The Bidder shall supply all turbine integral piping, such as the piping between the main stop valves and the turbine ; between the combined reheat stop and control valves and the turbine. The
Bidder shall state the allowable forces and moments at the face of each piping connection on the turbine for the reactions from The KNOC's piping. The Bidder shall design and arrange for the transfer of these forces and moments from the face of pipe connections to an internal point of the turbine.
6.5-18 KHABAT TPP UNITS 1&2 - VOLUME I
(2) The operation of the turbine shall not be affected, in any manner, by the interconnecting piping and the reactions from the steam piping connected to the main and reheat stop valves and HP exhaust, provided that piping forces and moments on the turbine connections are not excess of the allowable forces and moments specified by the Bidder in this specification. (3) All hangers and supports, including travel stops, necessary to support valves and piping supplied with the turbine shall be furnished by the Bidder. B.
Drain & Vent Valves, Piping All drain and vent valves, piping (with hangers and supports) shall be furnished. A second manual lock-open shutoff valve shall be provided for each drain valve.
6.5.8.15 Thermal insulation The turbine casing, valves, piping and equipment shall be thermally insulated by
non-asbestos,
non-combustible
materials
to
obtain
the
surface
o
temperatures not to exceed 55 C. The top insulation blanket consist of mineral wool with a special designed glass fabric on both sides. The outside fabric is coated with silicone rubber to make the surface oil repellent. All insulation which is normally removed during routine turbine inspection shall be of the reusable "blanket" type.
All blankets shall be properly tagged and
identified on an insulation arrangement drawing supplied with the turbine. Aluminum jacketing on all pipe insulation shall be included.
6.5-19 KHABAT TPP UNITS 1&2 - VOLUME I
6.6
Condensate System
6.6.1
System Description The condensate system shall deliver the condensate from the condenser to the deaerator storage tank. The condensate shall be chemically treated by injecting ammonia and hydrazine to adjust the pH level, scavenge residual oxygen and thus minimize corrosion.
The condensate system also shall
provide water to various desuperheater, seal water to equipment, and makeup water to miscellaneous systems. The condenser air removal system shall be established and maintained the required vacuum in the condenser. The Demi, Water make-up system shall maintain normal levels in the condenser hotwell under all operating conditions and provide water to various desuperheaters, seal water to equipment, and makeup water to miscellaneous systems. 6.6.2
System Design Criteria A.
The system design is based on the heat balance for the maximum calculated load with valve wide open (VWO).
B.
The minimum flow recirculation line for the condensate pumps and the gland steam condenser will be provided down stream of the gland steam condenser.
C.
The main condensers shall be designed to prevent tube failures caused by steam impingement from the turbine bypass or exhaust.
D.
The tubes shall be expanded and seal welded to prevent the water leakage between tubes and tubesheets
6.6.2.1
Bypass design A.
The feedwater heaters No. 1, 2, 3, and the gland steam condenser shall have their individual bypass lines.
B.
Bypass line including bypass valve for low pressure feedwater heaters shall be sized for the same pressure drop as the total pressure drop in the heater and in the portions of the main condensate piping between the points of take-off and return of the bypass line. The maximum allowable pipeline velocity in the bypass line may exceed the recommended value of the design flow velocity.
6.6-1 KHABAT TPP UNITS 1&2 - VOLUME I
6.6.2.2
Start-up A.
Corrosion occurs in equipment in which water remains after shutdown, especially if it is exposed to air. Oxygen must be removed from the system because the corrosion rate is proportional to the Oxygen content.
B.
During the clean-up process, the vacuum pumps should be operated to evacuate air from the main condenser steam space to achieve a condenser vacuum corresponding to the condensate temperature.
C.
During start-up and low load operation, the normal condensate flow will not be adequate to meet the minimum flow requirements for the protection of the gland steam condenser. Therefore, a minimum flow recirculation line to the condenser will be provided downstream of the gland steam condenser.
6.6.2.3
Normal operation A.
During normal operating mode, the condensate feedwater system should be closely monitored and chemically controlled. This is achieved by analyzing adequate samples and compensating with appropriate chemical feeds.
B.
At partial loads there is higher possibility of air inleakage regardless of equipment air-proof design. Therefore, special attention is required to the parts which have possibility of air in-leakage : condenser connections, flanges, valve stems, gland turbine seals, etc.
C.
Make-up water to the condensers should be admitted into the steam space above tube bundle. This way, the make-up water temperature is increased close to that of the saturated steam and helps thermal deaeration of make-up water.
6.6.2.4
Abnormal operation A.
When conductivity of condensate water which exist in condensers, exceeds the allowable limit due to scooling water leakage caused by tube rupture, the hotwell and circulating water lines must be isolated and contaminated condensate water must be pumped to the waste water treatment system.
B.
The low pressure feedwater heaters will be designed to perform satisfactorily during system load transients as well as during abnormal
6.6-2 KHABAT TPP UNITS 1&2 - VOLUME I
modes of operation when various heaters are taken out of service for repair and maintenance. 6.6.2.5
Component description A.
Condensers 1) Quantity : Single(1) shell 2) Type : a) Single pressure, two pass(double) condenser. b) Tube arrangement : Traverse the turbine shaft 3) Design parameters : a) Tube velocity : 2.1 m/s b) Cleanliness factor : 90% c) Shell design pressure : Full vacuum and per the HEI standards for steam surface condenser. d) Waterbox design pressure : Per the HEI e) Hotwell storage : Seven (7) minutes of storage capacity at the normal water level and five(5) minutes minimum at the low water level, based on the design basis of the condensate flow. f) Oxygen content of condensate at outlet of condensers : 7 ppb g) Cooling Water temperature : [30℃] h) Cooling Water temperature difference : [Max 12℃ ] i) Materials : (1) Tube : Titanium (2) Tube sheet : Carbon steel plate covered with titanium (3) Tube plate : Titanium or carbon steel plate covered with titanium cladding
B.
Condensate pumps 1) Quantity : Two(2)×100% capacity 2) Type : Vertical can type, centrifugal, constant speed, motor operated 3) Design flow : the maximum continuous flow(VWO) plus a margin for control purposes and to cover for pressure changes during transient operating conditions plus a 5% margin to cover for pump wear between overhauls. 4) Design head : the rated total head shall include a 20% margin on the frictional resistance part of the total head at a flow corresponding to the normal maximum flow(VWO) plus the margin for control purposes 6.6-3 KHABAT TPP UNITS 1&2 - VOLUME I
5) Motor rating : a margin of at least 5% over the maximum power demand 6) One(1) condensate pumps shall be capable of continuous normal operation flow plus LP bypass spray flow. C.
Low pressure feedwater heaters 1) Quantity : a) LP feedwater No.1 and external drain cooler No. 1 : Each one (1)×100% capacity b) LP feedwater No.2 : One (1)×100% capacity c) LP feedwater No.3 : One (1)×100% capacity 2) Type and arrangement a) LP feedwater heater No.1 and external drain cooler No. 1 : Horizontal, U-tube, heater bay b) LP feedwater heater No.2 : Horizontal, U-tube, heater bay c) LP feedwater heater No.3 : Horizontal, U-tube, heater bay 3) Design requirement : a) Design performance : Based on VWO heat balance b) Design pressure (1) Tube : Total absolute pressure from the sum of the condensate pump shut off head with 5% margin. (2) Shell : 115% of extraction pressure based on VWO heat balance, but not less than 3.6kg/cm2.g, and also considering full vacuum condition. c) Design temperature (1) Tube : Saturated steam temperature corresponding to the shell-side design pressure. (2) Shell : Per HEI d) Tube material : stainless steel
D.
Gland steam condenser (steam packing exhauster) 1) Quantity : One (1)×100% capacity with Two(2)×100% steam packing exhausters 2) Type : Horizontal, single pass, shell and tube type 3) Design requirement a) Design performance : Based on VWO heat balance b) Design pressure and temperature : Same as the design parameters of the low pressure feedwater heaters 6.6-4 KHABAT TPP UNITS 1&2 - VOLUME I
c) Tube material : stainless steel E.
Piping 1) Design requirements a) Suction piping of condensate pump (1) Design pressure : Full vacuum and 10kg/cm2.g(150psig) (2) Design
temperature
:
Saturated
steam
temperature
corresponding to the maximum condenser pressure during operation (3) Flow velocity : maximum 1 m/sec b) Discharge piping of condensate pump (1) Design pressure : Total absolute pressure from the sum of the condensate pump shut off head with 5% margin (2) Design temperature : Temperature of condensate from last heater in condensate system of VWO heat balance (3) Flow velocity : 2.8 m/s - 4.6 m/s in NPS 50 mm thru NPS 175, 4.6 m/s in NPS 175 mm and larger F.
Condenser vacuum pumps 1) Quantity : Two (2) × 100% capacity for condenser 2) Type : Rotary liquid ring 3) Capacity : Per HEI standards 4) Accessories a) Seal water cooler (1) Type : Shell-tube type (2) Liquid : Cooling water (tube side), seal water (shell side) b) Moisture separator(Standard accessory)
6.6.2.6
The condensate rejection line shall be located downstream of the steam packing exhauster. The line shall contain a control station consisting of an air operating control valve with two isolation valves and a bypass valve.
6.6.2.7
The system minimum flow recirculation line shall provide a minimum flow recirculation protection for the condensate pump and the SPE. The line shall be sized for the minimum flow requirement of the condensate pump or the minimum flow requirements of the SPE, whichever is larger.
6.6.2.8
The minimum recirculation line shall contain a control station consisting of an air operated control valve with two manual isolation valves and a manual bypass valve. 6.6-5 KHABAT TPP UNITS 1&2 - VOLUME I
6.6.2.9
The low-pressure heater No.1 shall be provided with motor operated isolation valves at the inlet and outlet of the heater vessel and also in the vessel bypass line.
6.6.2.10 One(1) outdoor demi. Water storage tank per unit will be provided for makeup and initial fill of the condensate system. Makeup water to the demi & condensate storage tank will be provided from the demineralized water system. A motor operated control valve in the demineralized water makeup line control the level in the tank.
A condensate transfer pump will be located
in the makeup line to condenser hotwell. The condensate transfer pump will be used for the condensate system initial fill and the main boiler cold fill. 6.6.2.11 The demi. water transfer pump supply condensate from the demi storage tank to the following facilities and systems. A.
Feedwater storage tank
B.
Condenser hotwell
C.
Closed cooling water head tank make-up
D.
Condensate system header
6.6.2.12 The demi. water storage tank shall supply condensate to the condenser. 6.6.2.13 The gland seal steam concenser shall be a tube and shell heat exchanger which condensate the excess steam exhausted from the turbine highpressure shaft seals and the turbine control valve steam packings. 6.6.2.14 The gland seal steam concenser shall be provided with two isolation valves and a by-pass line with a normally closed valve. In case of a tube leak all condensate flow shall be bypassed. 6.6.2.15 The gland seal steam concenser shall be designed for full condensate flow passing through the inlet and outlet nozzles. 6.6.2.16 Downstream of the gland steam condenser a sub-header off the condensate supplies water to the following miscellaneous systems : A.
Makeup to auxiliary steam system
B.
Makeup to valve seal water
C.
Makeup to gland steam desuperheater
D.
Makeup to chemical feed system
E.
Makeup to L.P turbine exhaust hood spray
6.6-6 KHABAT TPP UNITS 1&2 - VOLUME I
F.
Makeup to waterbox vacuum pump and condenser vacuum pump seal water
G. Makeup to closed cooling water system H.
Makeup to chilled water system
6.6.2.17 The condenser and condensate system shall be chemically cleaned in the field prior to operation. 6.6.3
Condenser
6.6.3.1
Design conditions A.
The equipment will be located inside the turbine building and subject to the environmental conditions given in Volume Ⅱ,schedule A” Site Particulars “.
B.
The condenser shall be designed to operate in accordance with design requirements when receiving steam, moisture, condensate, feedwater and drains in the Valve Wide Open(V.W.O) Heat Balance.
C.
L.P Turbine Bypass 1) The condenser shall be designed to accept the flow from the low pressure turbine bypass system. Hot reheat steam flow will be discharged to the condenser shell, bypassing the low pressure turbine, during the bypass mode. The steam dumped to the condenser will enter condenser shell through a penetration which connect with the internal distribution piping within the condenser. The bypass steam flow and pressure, temperature shall be increased by 10 percent during abnormal condition. 2) The L.P turbine bypass steam inlet valve will automatically close when the condenser pressure reaches [127] mmHgA. 3) The L.P. turbine bypass discharge shall be designed to prohibit impingement on tubes and other components. 4) The two(2) measuring points of temperature instrumentation shall be fully engineered to ensure proper detection of the temperature inside of condenser to be caused by L.P. steam bypass operation.
D.
The condenser shall operate without noise and harmful vibration at all loads. It shall be designed to receive, distribute, and dissipate thermal and kinetic energy introduced by the conditions imposed during startup, shutdown, transient, and normal operation. And also during startup and/or
6.6-7 KHABAT TPP UNITS 1&2 - VOLUME I
cold season, one circulating water pumps will be taken out of service when not needed. One tube bundle of one shell may be out of service. E.
Hotwell condensate discharge temperature at the design condition and 50% through 100% load range shall be equal to the saturation temperature of the steam in the shell.
F.
The dissolved oxygen content of condensate shall not exceed 7 ppb for the design condition in condenser.
G. The temperature of the gas/vapor mixture being extracted from the condenser air cooling section shall be at least 4.2 deg. C(7.5 deg. F) less than the saturated steam temperature corresponding to the condenser pressure at design load. 6.6.3.2
Performance The Bidder shall guarantee that all equipment and materials will comply with all applicable code. The following performance factors are to be specifically guaranteed in writing for the condenser. A.
Condenser pressure [3.6 inch(92.5mm)]Hg A measured in accordance with ASME performance Test Code 12.2 for Steam Condensing Apparatus for the design condition shown in performance guarantee sheet.
B.
At the design condition the temperature of effluent condensate shall not be less than the saturation temperature for the pressure existing in the condenser shells.
C.
The dissolved oxygen in the condensate from the hotwell shall not exceed 7 ppb shown on HEI Standard
6.6.3.3
Design features A.
General 1) The condenser shall have ample space for the proper distribution of steam and water admitted to the shell, for the liberation and removal of air and noncondensable gases from the steam and water, and for the rapid and adequate drainage of condensate to the hotwell. Steam paths shall be designed to minimize quiescent zones at all operating conditions and prevent the excessive accumulation of condensate. 2) The internal parts of the condenser shall be arranged so that condensate leaving the hotwell shall approach the steam temperature 6.6-8 KHABAT TPP UNITS 1&2 - VOLUME I
with no observable difference. The condensate shall be deaerated to an oxygen content not to exceed that stated in Paragraph 6.6.3.2.C) under the restrictions listed in the Steam Surface Condenser Standard(HEI). 3) Lifting lugs shall be provided on all water boxes and wherever necessary
on
the
condenser
for
assembly,
installation,
or
maintenance. 4) All parts and components shall be capable of expanding and contracting through complete cycles of operating pressures and temperatures, including start-up, shutdown, pre-startup system cleaning operation, etc, without damage. B.
Condenser Shell 1) The condenser shall be adequately braced and stiffened to resist the specified design pressures without leaks or damage under all conditions of operation. The condenser shell shall be constructed of steel plate conforming to HEI standards . 2) Steam and drains at high temperatures and/or requiring deaeration should enter the condenser at a suitable elevation above the hotwell. Other steam and drain lines may enter into the condenser hotwell. All flows entering the condenser shall discharge through sufficient perforated pipes or against baffles as required to deflect the flows and eliminate the impingement on tube, shell and internal component. 3) The lines shall be arranged to ensure effective condensing in the tube bundle and to ensure that the exhaust hood temperatures will be kept within design limits. The design of perforated pipe or baffle distribution devices shall be in accordance with the principle of EPRI CS-2251. 4) Wherever possible, perforated spray pipe instead of the impingement baffles at high pressure drains shall be used. Impingement baffles, if any, shall be attached to the shell with full penetration welds and liquid penetrant tested in accordance with ASME Section VIII Division 1. 5) Special attention shall be given to shell connections handling high temperature steam. Thermal sleeves shall be provided to prevent shell cracking for piping that have temperatures of [149] deg. C and higher. 6.6-9 KHABAT TPP UNITS 1&2 - VOLUME I
6) The condenser shell shall be designed to allow for differential expansion between shell and tubes by a suitable method. All provisions to compensate for differential expansion between tube material and condenser shell material shall be based upon the circulating water temperature rise associated with operating at full load with one half of the specified circulating water flow. 7) The proper structures shall be furnished above the tube bundle to permit inspection of peripheral tubes in the bundle shoulders and other equipment in the steam space. The proper structures shall bridge across the center lane between bundles in condenser with divided waterboxes to permit access all around. At least two 500 mm x 600 mm(20 inch x 24 inch) openings with bolted and hinge covers shall be supplied in the shell to provide access to the proper structure. The two openings shall be in accessible location opposite each other. Similar access is also required in the hotwell. 8) Shell pressure boundary plates and welds shall be provided with a corrosion allowance of minimum 1.6 mm (1/16″) on each wetted side in contact with steam or condensate. 9) Ground pads shall be provided at two locations on each condenser shell for connection to ground grid. C.
L.P. Turbine Bypass Steam Distribution Piping. 1) The Bidder shall design the condenser to accommodate thermal and/or vibration stresses induced by the operation of the L.P. bypass system. 2) The Bidder shall furnish calculation to demonstrate that the location of the steam distribution piping within the condenser does not endanger the periphery of tube bundles and structure members. 3) The spray pattern of the steam distribution piping shall be designed in a such manner as to protect condenser tubes against direct contact of the spray. 4) The drain line for steam distribution piping shall be arranged for self drainage into hotwell.
Suitable provision for free movement of the
drain line shall be made.
6.6-10 KHABAT TPP UNITS 1&2 - VOLUME I
D.
Waterboxes 1) The single shell condenser shall have 2 tube bundles and that water boxes configuration must be designed to enable access for tube repair and manual cleaning for 1 side of condenser, while turbine is in operation 2) The condenser waterboxes shall be of welded steel lined with rubber and shall have ample strength to resist the external and internal pressures specified, mechanical forces due to expansion and contraction of the system as a whole including circulating water piping, and reactions that may be created by the expansion joints. 3) Waterboxes shall be supported off the condenser shell independent of the tube sheets in a manner that permits water box removal. All bolted joints shall be provided with full face asbestos free inserted rubber for waterbox side. 4) The internal design of the waterboxes shall be free of ribs and stays. Grab bars, ladders, brackets required at proper intervals to support temporary scaffolds, cathodic protection anodes, and other projecting members shall be designed to result a minimum interference with smooth flow. 5) The waterboxes shall be designed to receive and deliver water to and from the tubes and from and to the circulating water nozzles with minimum disturbance. For this purpose, the internal design, including ribs, access doors, handholes, stays, and all similar structures shall be arranged and streamlined to promote the natural flow of the water. Cavities, depressions, or low points that could accumulate debris will not be acceptable in the waterboxes. To ensure that air will not accumulate, the necessary external connections shall be provided for proper venting at the points where air could accumulate. 6) Waterboxes shall have suitable access doors (minimum 600 mm in diameter) with simplified closing devices including ladder so that tubes and tubesheets may be cleaned and inspected rapidly and conveniently. The access doors shall avoid possible interference with existing
installations
around
the
condenser.
Adequate
pipe
connections shall be provided for priming, venting, and draining the entire water system. 6.6-11 KHABAT TPP UNITS 1&2 - VOLUME I
7) Permanent provisions such as ladder, clips, support grids etc., shall be provided for frequent waterbox and tube cleaning. To prevent a hazard to personnel, the inlet and outlet connections shall have suitable protection, such as bars across the openings or removable safety grids. These shall be arranged so that they will not interfere with access for cleaning. 8) The circulating water passages shall be designed to prevent any damage to condenser tubes and tubesheets due to localized high velocities. The inlet waterbox design shall ensure adequate depth and suitable configuration so that a uniform velocity will be obtained as the water approaches and enters each tube. In addition, entrance velocity to the inlet waterboxes and exit velocity from the outlet waterboxes shall be considered in the design to obtain a uniform flow pattern to and from the tubes. 9) The Bidder shall furnish rubber expansion joints for the circulating water inlet and outlet pipes. Expansion joints shall have rubber flanges. They shall have individual solid steel ring reinforcement with a carcass of woven cotton or acceptable synthetic fiber. Joints shall be constructed to pipeline size and meet working pressures conditions, and face-to-face measurements as designated. Unless otherwise
specified,
flanges shall be of AWWA C207
CLASS D, Ring type. 10) The corrosion allowance shall be a minimum of 3.2 mm (1/8″) per side in contact with circulating water in the waterbox. 11) An adequate number of hinged manhole covers shall be provided in each condenser waterbox to give access including ventilation to the whole of the area of the tubeplates for inspection or cleaning. The doors shall be arranged so that they may be opened quickly without the use of lifting tackle or special tools. Where necessary for safe access to the manhole doors, galleries or platforms, complete with all necessary ladders and hand railing shall be provided. These galleries or platforms shall be arranged to include sections, which are easily removed to facilitate removal of the waterbox. If necessary, safety grates shall be provided over the waterbox/CW pipe connections. E.
Tubes
6.6-12 KHABAT TPP UNITS 1&2 - VOLUME I
1) Condenser tubes shall be made from annealed titanium strip and shall conform to the requirements of ASTM B338 Grade 2. The following impurity limitations shall not be exceed; - Oxygen Maximum 0.16 percent - Iron Maximum 0.15 percent 2) The tube size shall be 22.225 mm (7/8〃) O.D, and minimum wall thickness 25 BWG for condensing section and air removal section, minimum wall thickness 22 BWG for impingement zone respectively. 3) The number and arrangement of tubes in the exhaust impingement zone shall be designed to effectively protect all tubes from impingement damage caused by the flow of the exhaust steam and L.P. bypass steam dump. The Bidder shall submit tube arrangements for the condensing and impingement zone. 4) Careful consideration shall be given to the tube bundle design to effect free access of steam to the entire tube surface with minimum pressure drop. At the same time, adequate steam velocities shall be maintained throughout the tube bundle to prevent air blanketing of tubes. The arrangement of the condenser steam paths shall be designed so that all noncondensable gases shall be directed to the air cooler section. The arrangement shall also prevent damage to the tubes by steam impingement. The Bidder shall supply internal stainless steel pipes to convey vapors and non-condensable gases to the offtake to be located at the circulating water outlet end of the condenser. F.
Tube Support Plates 1) Tube support plates of the same material specification as the shell and proper thickness shall be spaced to reduce tube vibration and fretting with particular reference to resonance caused by mass flow of circulating water and steam. Maximum spacing between any two adjacent tube support plates or between a tube support plate and a tube sheet shall be complied with the method outlined in HEI standard. 2) Holes for the tubes shall be drilled and reamed to provide a free sliding fit for the tubes and shall be chamfered on both sides in such a manner as to remove all burrs which might score the tubes.
6.6-13 KHABAT TPP UNITS 1&2 - VOLUME I
3) Tube hole in the supporting plates shall be as small as possible, consistent with free lengthwise movement of tubes, slightly chamfered or rounded on both sides, and slightly offset vertically with corresponding holes in the tubesheet to provide for complete drainage of water. 4) Tube support plate shall be provided with minimum 1.6mm(1/16″) corrosion allowance on each side in contact with steam or condensate. 5) The preferred material for tube plates in contact with cooling water is solid titanium. Consideration will be given to titanium clad steel or other proven combinations providing satisfactory evidence of operating experience can be supplied]. If titanium clad tube plates are used, the cladding shall be applied by hot rolling or other approved method, and shall be of 5 mm minimum thickness. The clad tube plates shall be subject to full ultrasonic inspection to prove the integrity of the bonding in accordance with a recognized standard]. 6) The tubes shall be fixed into the tube plates by roller expansion followed by seal welding to the titanium surface of the tube plate at both ends of the tube. Sagging plates shall be supplied and arranged so that no periodic vibration of tubes shall be induced by the running of the turbine generator and its auxiliaries or by steam buffeting. The vertical location of the sagging plates shall be such that the condenser tubes are self draining when the machine is shut down. G. Tubesheets 1) The tubesheet cladding material shall be made from annealed titanium plate and shall conform to the requirements of ASTM B265 Grade 1. 2) The tubesheet backing material shall be made from carbon steel plate and shall conform to ASTM A516 Grade 70. 3) The tubes shall be expanded and seal welded at cooling water side of tubesheets. Joint between shell and tubesheet shall be welded. Waterboxes shall be bolted to the tubesheet. The titanium cladding on tubesheet shall be a minimum thickness of 6.4 mm (1/4″). The cladding shall cover 100 percent of the tubesheet backing plate. The plates after explosive bonding shall be press flattened. The cladding sheet shall be fabricated from one piece without welding. The 6.6-14 KHABAT TPP UNITS 1&2 - VOLUME I
deviation from flatness for each titanium clad tubesheet shall not exceed 3mm per 1500 mm, but bolting area shall not exceed 0.6mm per 300mm. Holes for tubes shall be accurately drilled in the tube sheets. Drilling and reaming of holes shall be performed in such manner as to ensure that the surfaces throughout the entire depth of the holes are smooth and free from any score marks. The shell side of all holes shall be chamfered.
Hole finish shall be 250 RMS.
Tube sheets shall be arranged for rolling at both ends. The explosive cladding process for joining of the titanium plate to the carbon steel backing plate shall be accomplished through the use of a proven procedure. 4) The corrosion allowance shall be minimum 1.6mm(1/16″) on each side in contact with steam or condensate. 5) Before fabrication of the tubesheet and waterbox, the Bidder shall submit a tubesheet stress analysis to prove adequacy of the tube sheet thickness under the specified design pressure. The analysis shall indicate the maximum tubesheet stresses and the maximum tube loads. 6) The tubesheets shall be connected to the condenser shell in a manner that permits the waterboxes to be removed without disturbing the tubesheets. H.
Hotwell 1) In hotwell, there shall be at least five(5) minutes of condensate retained below the low water level and two(2) minutes of storage capacity between the normal water level and the low water level for the normal operating range. The hotwell shall be fabricated of the same material specified for the condenser shell. 2) The hotwell shall include connections for gage glasses, level instruments, thermometers, and all other applicable instrumentation. 3) The hotwell condensate outlet box shall be suitably designed to eliminate vortexing. Access openings shall be provided to the hotwell. 4) The condensate flow path shall be designed so that the condensate is detained for a period of time as specified in paragraph 6.6.3.3.H) 1) before reaching the hotwell outlet box. This requirement is established so that a circulating water leak can be detected before contaminated condensate reaches the condensate pump. The point 6.6-15 KHABAT TPP UNITS 1&2 - VOLUME I
to which the condensate is directed prior to retention in each hotwell shall have a connection outside the condenser to allow a continuously flowing sampling stream to be automatically monitored for evidence of condensate contamination. The tube leak detection trough shall be provided beneath each tubesheet to detect tube-tubesheet leakage including connecting pipe from the trough to the outside of the condenser for connection to instrumentation. 5) The hotwell shall be provided with sufficient space between the water surface and the bottom of the tube bundle to permit steam flow under the tubes for condensate reheating and deaeration. 6) The hotwell shall be divided longitudinally to isolate each half from the other, so that the leak from any tube will contaminate only one-half of the hotwell condensate. The height of partition shall be adequate to preclude condensate overflow at maximum operating level. 7) Provide connections to gravity drain the hotwell from the normal operating level in 30 minutes or less. The design shall provide for complete drainage in case the water is contaminated. 8) The permanent, removal screen shall be provided in the hotwell at the entrance to the outlet well and also temporary screens for start-up operation condenser shall be provided. 9) The hotwell plates and welds shall be provided with a corrosion allowance of minimum 1.6mm(1/16") on wetted side in contact with steam or condensate. I.
Exhaust Necks 1) The exhaust necks shall be provided with all required openings, supports, and closure plates with provision for thermal expansion of feedwater heater and extraction piping located inside the exhaust necks. 2) The condenser neck shall have access manholes of sufficient size to pass the largest expansion joint of steam extraction piping through it. 3) Bracing shall be provided in the condenser neck to stiffen against vibration and vacuum loading. The condenser neck design shall be coordinated with the turbine and shall be compatible with the turbine exhaust nozzle to give minimum exhaust losses. Consideration shall 6.6-16 KHABAT TPP UNITS 1&2 - VOLUME I
be given to the turbine exhaust flow pattern at the exhaust flange. The distance piece and expansion joint for connecting the condenser to the turbine exhaust shall be streamlined where necessary to provide proper steam diffusion and to minimize exhaust losses. 4) The Bidder shall provide and be responsible for all design(supports, routing, stress analysis) and material of all extraction piping in the condenser neck. All piping within the condenser shall be designed, fabricated and erected in accordance with ASME B31.1.
All
extraction piping and expansion joints shall be completely covered with lagging and spacers to form a 25 mm deep insulating air space. Expansion joints shall be provided in both horizontal and vertical sections of piping as necessary to ensure that reactions on turbine connections as specified by the turbine manufacturer are within acceptable limits with piping anchored at neck penetration. 5) L.P. turbine bypass system as indicated on the condenser arrangement drawing shall be discharged into the condenser above the tube bundle. Condenser manufacturer shall be responsible for the analysis of the distribution of steam and the design and supply of the distribution devices. 6) The corrosion allowance in the exhaust neck shall be a minimum of 3.2 mm (1/8"). 7) Provide exhaust connection with an expansion joint. Expansion joint shall comply with the requirements
of the Expansion joint
Manufacturers Association Standards. 8) Performance test pressure connections and basket tips shall be provided for the condenser acceptance test, with location and number of connections in accordance with ASME PTC 12.2 requirements. 9) Structural members in the condenser neck shall be aligned with the turbine exhaust structural members provided by the turbine to the greatest extent possible without compromising integrity and strength of the condenser. 10) Bracing shall be provided in the condenser neck to stiffen against vibration and vacuum loading. 11) The bidder shall provide absorption for the expansion movement between the condenser and turbine by using a condenser neck expansion joint. The expansion joint connecting the turbine exhaust 6.6-17 KHABAT TPP UNITS 1&2 - VOLUME I
and the condenser shell shall be a stainless steel type having a welded/bolted connection to turbine exhaust and condenser neck. The end connection at the turbine end shall be compatible with the turbine exhaust details. A stainless steel liner shall be provided over the joint to prevent turbulence and direct impingement on the stainless steel expansion bellows J.
Distance Pieces 1) Distance pieces shall be provided with the exhaust neck expansion joint of the material specified in Paragraph 6.6.3.3 L). The distance piece landing bar shall be welded to the turbine casings.
K.
Connections 1) All necessary nozzles and connections shall be provided including, but not limited to, the following services : a) L.P. turbine bypass b) Removal of air, vapor and noncondensable gases c) Admission of makeup, normal and rapid d) Feedwater heater vents e) Normal and high level heater drains f) Condensate pump minimum flow recirculation g) Turbine stop valve and intercept valve before and after seat drains, similar returns and miscellaneous high energy drains to flash tank(flash box) h) Seal Steam i) Instrumentation required for operation of the condenser equipment per Paragraph 6.6.3.3 I) 2) and 6.6.3.3.I) 4) 2) Connections in the shell and on thermal sleeves 50mm (2inches) and smaller, except liquid level control, shall be of the socket weld type. Those 65mm (2-1/2 inches) and larger shall be of the butt-weld type. Connections in the waterbox shall be flanged and shall be large enough to be lined with rubber. 3) All test connections and basket tips, including pressure connections per each shell, shall be furnished by the Bidder for an ASME turbine acceptance test. 4) The Bidder shall provide a description and sketches of proposed methods of distributing the following flows ; a) L.P turbine bypass 6.6-18 KHABAT TPP UNITS 1&2 - VOLUME I
b) Main steam line warm-up drains c) Extraction steam line drains d) Condensate pump recirculation e) Makeup water f) Seal steam 5) Miscellaneous item as following; a) A direct reading level gauge for each condenser hotwell. b) A level transmitter for each hotwell with high and low level alarm and indication to the unit PCS c) A vacuum measuring grid of a design to be approved with four measuring connections (and four isolating valves) located within 150 mm of the condenser inlet flange level. d) Vacuum breaker valve e) Thermometer pockets in the steam space, air suction branches and hotwells. f) One 100 mm (minimum) bore branch and valve for draining each trough or reservoirs of the condenser hotwell. g) 100 mm (minimum) bore condenser shell steam space water filling connection with blank flange on each shell for hydraulic pressure test. h) 100 mm (minimum) drain valve and piping from each waterbox to nearest convenient floor drain. i) Plugged bosses; two on each circulating water inlet and outlet branch for pressure gauge connection. j) Two compound (combined pressure and vacuum) pressure gauges, one for each circulating water outlet branch. k) Thermometer pockets on the inlet, return end and outlet waterbox branches. Two pockets in each branch, one for thermocouple input to PCS and one a test pocket. l) Arrangement to allow chemical dosing of the inlet waterboxes. m) 80 mm (minimum) bore vent valves in each waterbox piped to a convenient drain via a tundish. n) Priming connection on each waterbox. o) One diffuser at each point of discharge into the condenser where impingement on tubes could occur. p) Condensate level control equipment. 6.6-19 KHABAT TPP UNITS 1&2 - VOLUME I
q) Condenser priming indicator on each cooling water discharge pipe. r) Hot well conductivity monitoring probes with associated continuous monitoring equipment. (manual sampling facilities shall be provided from each condenser half to enable rapid leak location). L.
Materials 1) The condenser materials shall be in accordance with the specified below and the requirements identified in data sheets. a) Exhaust neck expansion joint - Stainless steel : ASTM A240 Type 304L b) Metallic expansion joints and lagging for extraction piping - Stainless steel : ASTM A240 Type 304L c) Spacers for extraction piping - Carbon steel : ASTM A36 or equivalent d) Tubes - Titanium : ASTM B338 Grade 2 e) Tube sheet - Base : Carbon steel (ASTM A516 Grade 70) - Clad : Titanium (ASTM B265 Grade 1) f) Tube support plate - Titanium or titanium clad steel(A36) or equivalent g) Shell and hotwell, neck piece - Carbon steel : ASTM A285 Grade C or equivalent h) Waterbox and circulating water pipe - Carbon steel (ASTM A516 Grade 70 or equivalent) with rubber lining i) Impingement baffles/perforated spray pipes - Stainless steel : ASTM A240 Type 304L/ASTM A312 Type 304L or equivalent - Carbon steel : ASTM A285 Grade C/ASTM A53 Grade B or equivalent - Alloy steel : ASTM A335 Grade P11 or P22 or equivalent Material shall be selected according to the temperature-pressure rating. 2) Material certification of the chemical analysis and mechanical properties of the above materials shall be provided.
M. Cathodic Protection System 6.6-20 KHABAT TPP UNITS 1&2 - VOLUME I
1) The Bidder shall provide a cathodic protection system to minimize the galvanic corrosion attack of the condenser tube sheet. The cathodic protection system shall be designed in accordance with the following requirements. a) The control potential of the cathodic protection installation should be 700 millivolts SCE(Saturated Calumel Electrode) in order to ensure against titanium hydride formation. b) The electrode should be located to indicate maximum polarization potentials from the anode. Anode shall be treated MMO-Ti or equivalent, with space to provide protective current density to all interior surfaces as specified by the National Association of Corrosion Engineers Level of Protection Potential. Cathodic protection circuit shall be calculated with one Zn and two anode per one circuit. c) Individual anode output currents should be monitored. It may be necessary to add resistors to reduce the output from anodes whose output is higher than normal output of the others. d) A method of calibrating the electrodes should be established for
assurance that the critical potential for titanium hydride
formation is not reached. e) The anode entry stations should be built into the waterbox prior to the application of the waterbox lining. 2) The rectifier unit shall be complete with weather-proof enclosure (NEMA Type 4X) and shall be rated 400V AC 3phase 50 Hertz.The rectifier shall be properly protected on input and output sides against switching and lightning surges. 3) The rectifier control panel shall be equipped the transmitter port to be communicated with the main host computer of cathodic protection system to be provided by the Yard Island. 4) The impressed current system shall include zinc reference electrodes and auto controller to monitor the degree of protection. 5) The Bidder shall design and supply a complete impressed current cathodic protection system including, but not limited to anodes, rectifiers, local control panels including microprocessor based control and monitoring device, pull box, internal wiring, cables etc., all required for satisfactory operation of the entire system. 6.6-21 KHABAT TPP UNITS 1&2 - VOLUME I
Consideration shall be given to protect the condenser tube sheet made of clad plate. The Bidder shall also supply additional switches to annunciator system trouble in the main control room. The local control panels shall be enclosed type and will be located near the condenser water boxes. Size and location of openings shall be determined by the Bidder. Size of openings shall be adequate to allow proper application of the specified coating of the water boxes. N.
Manufacture 1) Shop Assembly The condenser shall be of welded construction and prefabricated into the largest sub-assembly that can be shipped to minimize field welding. The condenser shell and internals including tubes shall be completely assembled in the Bidder's shop. Condenser that can be shipped in sections shall be piece marked and provided with fit-up lugs to facilitate erection in the field. All nozzles, sleeves, baffles and thermal sleeves shall be welded to the condenser shell in the shop. The final field weld location shall be shown on the relevant condenser drawing. 2) Welding a) The Bidder shall provide written welding procedures, repair procedures and procedure qualification records. Each procedure shall be prepared and qualified in accordance with the requirements of ASME Section IX and this specification. Each procedure shall be reviewed and accepted by the KNOC before the Bidder or his Sub-Bidder may perform such welding. the KNOC's inspector will review performance qualification records for individual welders. Welding procedures and procedure qualification records shall be in the form of clear, sharp, reproducible prints and may be prepared on Forms QW-482 and QW-483 as shown in the ASME Code, Section IX, or similar. 3) Field Weld End Preparation The Bidder shall prepare the field weld sections of all condenser parts in such a way that the field weld will be done inside the condenser shell. This is to avoid possible interference with the existing 6.6-22 KHABAT TPP UNITS 1&2 - VOLUME I
installation around the condenser when performing field weld operation. Welding surfaces and heat affected zone that the field welding will be done shall not be painted with any paint or zinc primer to protect for zinc contamination. O. Cathodic Protection System 1) The Bidder shall provide a cathodic protection system to minimize the galvanic corrosion attack of the condenser tube sheet. The cathodic protection system shall be designed in accordance with the following requirements. a) The control potential of the cathodic protection installation should be 700 millivolts SCE(Saturated Calumel Electrode) in order to ensure against titanium hydride formation. b) The electrode should be located to indicate maximum polarization potentials from the anode. Anode shall be treated MMO-Ti or equivalent, with space to provide protective current density to all interior surfaces as specified by the National Association of Corrosion Engineers Level of Protection Potential. Cathodic protection circuit shall be calculated with one Zn and two anode per one circuit. c) Individual anode output currents should be monitored. It may be necessary to add resistors to reduce the output from anodes whose output is higher than normal output of the others. d) A method of calibrating the electrodes should be established for
assurance that the critical potential for titanium hydride
formation is not reached. e) The anode entry stations should be built into the waterbox prior to the application of the waterbox lining. 2) The rectifier unit shall be complete with weather-proof enclosure (NEMA Type 4X) and shall be rated 400V AC 3phase 50 Hertz.The rectifier shall be properly protected on input and output sides against switching and lightning surges. 3) The rectifier control panel shall be equipped the transmitter port to be communicated with the main host computer of cathodic protection system to be provided by the Yard Island. 4) The impressed current system shall include zinc reference electrodes and auto controller to monitor the degree of protection. 6.6-23 KHABAT TPP UNITS 1&2 - VOLUME I
5) The Bidder shall design and supply a complete impressed current cathodic protection system including, but not limited to anodes, rectifiers, local control panels including microprocessor based control and monitoring device, pull box, internal wiring, cables etc., all required for satisfactory operation of the entire system. Consideration shall be given to protect the condenser tube sheet made of clad plate. The Bidder shall also supply additional switches to annunciator system trouble in the main control room. The local control panels shall be enclosed type and will be located near the condenser water boxes. Size and location of openings shall be determined by the Bidder. Size of openings shall be adequate to allow proper application of the specified coating of the water boxes. P.
Foundations and Supports 1) The Bidder shall provide complete structural load information with the condenser outline drawings. Calculations shall be furnished with the structural load information. 2) The calculation shall include assumptions as to which loads are concurrent; tabulations of the combined loads to result in the maximum load for which the condenser is to be designed, and the magnitude, direction, and point of application of all loads for the condenser at the flooded test condition and for operating conditions of condensing and noncondensing, where both halves of the condenser are operating and where either half of the condenser is not operating. 3) The condenser outline drawings shall include location, dimensions, and details of all support plates attached to the condenser and furnished by the Bidder, including guide bars, Teflon sliding plates and anchor plates. Size, locations, and connection details of bolts and nuts shall also be included. 4) The effects of the following forces shall be considered by the Bidder a) Weights of condenser, appurtenances, and contents b) Vacuum and pressure loads c) Thermal expansion and contraction d) Hydraulic thrust at inlet and discharge connections e) Frictional resistances on sliding plates 6.6-24 KHABAT TPP UNITS 1&2 - VOLUME I
f) Seismic forces g) Hydrostatic test loads 5) The design will include the foundation and any connections for the purpose of transmitting vertical and horizontal loads.
6.6.4
Condensate pumps
6.6.4.1
Design condition A.
Type of Condensate Pump The pumps shall be the vertical in-barrel, centrifugal type with all necessary accessories for operable units.
B.
Operational Requirements 1) Each condensate pump shall meet the operating conditions. 2) The curve of total head vs. flow for the condensate pumps proposed shall pass through of all of the operating points. 3) The pumps shall operate free of cavitation over the entire range of operation. 4) Specific speeds and suction specific speeds shall be in accordance with those proposed in the Hydraulic Institute Standards. 5) The pumps shall be designed in accordance with the Hydraulic Institute Standards, vertical centrifugal pump section. 6) The critical speed of rotating elements including the effects of lubrication, bearings and bearing supports shall be at least 25 percent above the maximum expected operating speed. 7) The pumps shall be designed so that, at any system flow from zero to maximum flow, the total head developed by the pumps shall equal or exceed the system head requirements. The pumps will be required to operate at minimum flow for extended periods. 8) The pumps head-capacity curve shall be continuously rising from maximum flow to shutoff. Shutoff head shall be not less than 120 percent of rated pump head. 9) The pumps shall be capable of operating singly or in parallel combinations both intermittently and continuously at any rate from minimum flow to maximum flow under all operating conditions outlined herein without cavitation, undue noise, or vibration. Vibration 6.6-25 KHABAT TPP UNITS 1&2 - VOLUME I
shall be within the limits outlined in the ISO 10816 and ISO 7919. The Bidder shall supply all instrumentations and control systems which will be required to protect of pump system. 10) Pump casing design pressure shall be not less than shutoff head with the maximum suction pressure. 11) Equipment furnished shall be free from fault in design, workmanship and material. 12) Each set of pumps shall be identical in design with all replacement parts being interchangeable. 13) Strainers with the differential pressure indicating transmitter for indication of fouled shall be furnished by the Bidder. 14) The pump shall have clockwise rotation when viewed from motor facing pump. 15) The pumps shall be selected so that the best efficiency point occurs at design point. 6.6.4.2
Performance data A.
The Bidder shall design that the proposed apparatus will operate quietly without undue vibration or noise under the conditions outlined herein, that the apparatus will be capable of continuous and satisfactory operation supported on the proposed structure under all specified conditions of operation outlined herein, that the condensate pumps performance will comply with all requirements outlined herein.
B.
No minus tolerance shall be allowed with respect to capacity, total head or efficiency, and no plus tolerance shall be allowed for the vibration amplitudes. The total head at guarantee capacity may vary by plus 5 percent.
6.6.4.3
Design features A.
The pump design shall allow for dismantling the pump and removal of the rotating element without removing the pump from its base or disturbing the suction or discharge connections.
B.
Parts subject to substantial temperature changes shall be designed and supported to permit free expansion and contraction without resulting in leakage, harmful distortion or misalignment.
C.
Parts subject to wear, corrosion, or other deterioration,
requiring
adjustment, inspection, or repair shall be accessible and capable of 6.6-26 KHABAT TPP UNITS 1&2 - VOLUME I
reasonable convenient removal when required. Where practicable, parts subject of wear shall have means of adjustment. D.
Bolts, nuts, studs and screws shall have coarse threads conforming to ASME standards or equivalent, and shall be furnished in accordance with the latest approved practice for the duties involved. Only hexagonal nuts shall be used.
E.
The Bidder shall certify that the proposed piping arrangement will not cause or otherwise contribute to harmful pump vibrations.
F.
Lifting lugs or eyebolts with means of attachment shall be provided to aid in the handling of heavy parts. Support point provided by the Bidder shall be designed for convenient connection to the foundation or supports.
G. It is the Bidder's responsibility to advise his sub-bidder's of the relevant specifications, and to ensure that they are fully conversant with the requirements of the KNOC. H.
Pumps and all assembly joints or junctions shall include alignment or centering fits as required to ensure accurate reassembly or alignment of all parts.
I.
Running clearance shall meet the requirements of API 610, latest edition
J.
Casing Assemblies 1) Casing bowls shall be the diffuser type with hydraulic surfaces finished to a smooth surface. 2) The discharge head shall be fabricated of steel with flanged suction and discharge nozzles. Flanges shall conform to the requirements of ASME B16.5. 3) Casings shall be of uniform high quality and of the Bidder's standard thickness with a 10 percent allowable variation. 4) The suction can shall be suspended from a foundation base ring of ample thickness to prevent warping and shall provide a flat machined surface to carry the matching machined base on the nozzle head. The can shall be provided with a vent and its associated vent isolation valve. 5) Velocity in the suction barrel shall be between 1.2～2 m/s and flow shall be controlled at the lower end of the barrel or pump inlet.
K.
Rotating Elements 1) Shafts shall be of adequate size to withstand the forces resulting from starting and operating conditions to which the pumps will be 6.6-27 KHABAT TPP UNITS 1&2 - VOLUME I
subjected. The shafts shall have adequate fillets at all shoulders and shall have provisions for locking each impeller in the proper position. 2) Main coupling between the column shaft and drive motor shaft shall be the rigid, adjustable spacer type with provisions for vertical adjustment of the rotor in the inner casing and shall be provided to allow removal of the mechanical seal without removing the driving motor. Coupling pins, nuts, or bolts shall be recessed, and no part shall project past surfaces of revolution. 3) Column couplings shall be type that ensures positive alignment of the shafts. They shall be suitable for convenient disassembly and shall properly realign the shafts on reassembly. 4) Access holes to the shaft and coupling shall be covered with 50mm wire mesh or similar method. 5) Impellers shall be the single suction enclosed type, except the first stage which may be double suction. All surfaces shall be machined or hand finished to a smooth surface. Impellers shall be keyed and individually positioned on the shaft. Each impeller shall be dynamically balanced after any alteration. 6) Wear rings shall be replaceable. If impeller wear rings are not included, the impeller hub shall be of sufficient thickness to allow their future installation.
Wear rings shall be rigidly positioned and
attached to prevent loosening. The wear rings shall be suitably hardened for the service. L.
Bearings Bearings located in the casing bowls, in the suction bell and on the lineshaft shall be non-copper bearing metal, and shall be lubricated by the pumped water.
Column bearing centers shall be spaced so that the
shaft will have proper guidance to be free of harmful vibration. Axial pump thrust shall be absorbed by the motor thrust bearings. The Bidder shall state the maximum limits of vibration and the method of measurement that will be used to determine correct operation of the pump and coupling before shipment. In no case shall be acceptable operating limits or alarm limits exceed Hydraulic Institute Standards. M. Shaft Seals and Sleeves 1) The shaft shall be provided with a replaceable sleeve positioned against a shoulder on the shaft and held in place by a shaft nut or 6.6-28 KHABAT TPP UNITS 1&2 - VOLUME I
equivalent. The sleeve shall be suitably hardened for the service and keyed to the shaft. 2) Shaft seals shall be the cartridge mechanical type. Shaft seal shall be designed to operate in a liquid, and the seal faces must be immersed in a liquid from the very beginning to prevent dry running. Pump shaft shall be sealed by the pumped fluid during normal operation. The Bidder shall provide complete sealing system including restriction orifice, flow gauges, filters, solenoid valves and instrumentations. N.
Supports 1) The discharge head shall support the motor and shall take external forces, including vertical and horizontal thrust resulting from a suction expansion joint plus the nozzle loads Equipment Nozzle Loads and transmit them to the supporting foundation. 2) The suction barrel shall be of welded steel plate with provisions for mounting and supporting the complete unit on a ring base grouted into the supporting concrete. The ring base shall be supplied by the Bidder, Provisions shall be made for continuously venting the suction back to the condenser. 3) Support rings or gussets shall be provided in the suction barrel to limit pendular motion of the pump assembly. The rings or gussets shall be tapered to facilitate assembly. 4) Nozzle head/motor support shall have a natural frequency at least 20 percent above operating speed.
O. Strainer 1) Each condensate pump shall be provided with one 500 mm, nominal diameter basket strainer and temporary screen for start-up. 2) The Basket strainer shall be constructed of stainless steel and ASME Class 150 lb RFWN flanges with a quick opening cover for basket removal. The strainer body shall be ASTM A216 Gr WCB. A stainless steel basket shall be furnished for condensate water service with a minimum free area of four times pipe size with less than 0.07 kg/cm2 pressure drop. The strainer shall be furnished with a drain connection. The strainer shall be hydrostatically tested per ASME B16.5, or an equivalent code P.
Drivers
6.6-29 KHABAT TPP UNITS 1&2 - VOLUME I
The motor thrust bearings for the condensate pumps shall have a minimum rated capacity of 120 percent of the maximum pump down thrust and shall have the capability to accept a momentary upthrust of at least 30 percent of rated down thrust. Q. Instrumentation and Controls 1) Field Instrument Requirements a) All dial type pressure indicators and temperature indicators shall be of liquid filled type to protect from vibration of pumps b) Refer to Section 8 c) Instrument shall be supplied by one(1) recognized manufacturer having wide experience in the manufacture, application as possible. R.
Vibration Monitoring Devices 1) The Bidder shall provide the vibration monitoring devices consisting of probes with protective housing, extension cables and transducers with housing for accurate, reliable vibration monitoring. 2) The radial vibration probes shall be provided with two probes per bearing radially at 90 degrees (X,Y). The dual axial vibration/position probes and keyphaser shall be provided for each pump. The Bidder shall submit installation drawing and detailed specification of the proximitor and keyphaser transducer system for approval by the KNOC.
S.
Materials 1) All materials used in constructing the equipment shall be the best suitable for the specified service. For the specific materials identified in the following list, the base bid shall be predicated on their use and guaranteed by the Bidder to be suitable for the service intended. The Bidder may bid alternative materials of equal or superior properties. 2) Materials for the pumps shall be as specified below (ASTM Designation) a) Can(Barrel) : Structural Steel(A36 with Fiberglass Reinforced Plastic Lining or Polyethylene Lining) b) Casing or Bowl : Gray Iron Casting(A48 Class 35) c) Impeller : 13% Chrome Stainless Steel(A743 Grade CA15) d) Casing wear rings : 13% Chrome Stainless Steel, Hardened(A743 Grade CA40 or A582 Type 416) 6.6-30 KHABAT TPP UNITS 1&2 - VOLUME I
e) Shaft : 13% Chrome Stainless Steel(A276 Type 410) f)
Shaft sleeves : 13% Chrome Stainless Steel, Hardened(A743 Grade CA40 or A582 Type 416)
6.6.5
Low Pressure Feedwater Heaters
6.6.5.1
Design condition A.
Type of Feedwater Heaters The type of LP feedwater heaters shall be of the horizontal shell and Utube design with integral drain cooling zones.
B.
Performance Requirements The heaters shall be designed to accept the load variations at a minimum rate of [10%] of MGR per minute between [50% MGR and 100% MGR], and at a minimum rate of [3%] of MGR per minute between [20% MGR and 50% MGR] and also transients from turbine or steam generator unit trips.
C.
Tubeside Velocity The maximum water velocity through the tube shall be in accordance with the Heat Exchange Institute Standard at the normal full load operating conditions and shall not exceed 3 m/sec(10 ft/sec).
D.
Temperature Changes The heaters shall be designed to ensure continuous, safe and economical operation providing the maximum reliability under the following conditions of temperature changes : The low pressure heaters shall be designed for the instantaneous temperature drop from normal inlet temperature to [50 deg.C].
E.
Allowable Pressure Drops The tube side / shell side pressure drop shall submit the values for condensate pump's TDH and others.
F.
Nozzle and Support Loads Supports for the feedwater heaters shall be capable of withstanding the loads and moments calculated by the Bidder in addition to normal loads and moments and shall be provided for transfer of loads to the condenser neck and building foundation by positive means, respectively.
G. Overload and Abnormal Conditions 1) The feedwater heaters shall be capable of operating at the overload and abnormal conditions as specified below without malfunction or 6.6-31 KHABAT TPP UNITS 1&2 - VOLUME I
damage to the heaters. The Bidder shall determine the effects of removing heaters from service and provide for those effects in the heater designs. The Bidder shall supply calculations and complete Technical Data form for abnormal conditions in bid data form. 2) Abnormal condition occurs when heaters are bypassed. Extraction steam flows and drain flows of heaters in service proportionally increase, based on heater performance, over design flows. Extraction steam pressure will be increased. 6.6.5.2
Performance data The Bidder shall design for all equipment and materials to comply with all applicable code. Performance in accordance with all specified conditions without excessive noise and vibration, overheating or physical damage to the equipment. The heaters shall be operable under the rapid starting or load changing conditions without any limitation. The following performance data of LP feedwater heaters shall be submitted specifically.
6.6.5.3
A.
Terminal temperature difference
B.
Drain cooler approach
C.
Tubeside pressure drop
D.
Shellside pressure drop
Design features The feedwater heaters shall be designed in accordance with the requirements of ASME Section VIII, HEI standards and this specification. The heaters shall conform to ASME Section VIII Division 1 rules. The heaters shall be designed, certified and documented in accordance with code. A.
Shells 1) The No.1 low pressure heater & external drain cooler and No2, 3 shall have removable shells. 2) Feedwater heaters shall be equipped with fixed supports at the channel and wheels or roller supports for the removable portion of the shell. 3) The heaters shall have welded shell-to-tube sheet or shell- to-shell skirt joints. Shell covers shall be welded to the shells. Feedwater heaters with welded shell-to-tube sheet or shell-to-shell skirt joints shall be provided with a cutting line. Cutting lines shall be clearly indicated on the heater shells and cutting line location shall be shown 6.6-32 KHABAT TPP UNITS 1&2 - VOLUME I
on Bidder's drawings. A minimum 200 mm(8") wide stainless steel flame protecting band shall be provided around the tube bundle beneath the shell cutting line. 4) A shell corrosion allowance of 1.6 mm(1/16") minimum shall be used. 5) Lifting and pulling lugs shall be furnished with each heater. All lifting lugs shall be adequately sized for the empty weight of the heater. 6) The Bidder shall furnish insulation support clips and weld to the shells and heads. Externally mounted heaters shall be provided with insulation clips. Cylindrical surfaces shall be equipped with insulation clips spaced at 90-degree intervals, arranged along the long axis of the heater at 457mm(18") intervals. Clips may be threaded 6.4 mm(1/4") studs, flat tabs with hole, or 6.4 mm(1/4") machine nuts. Irregular surfaces of heaters, such as the shell end or forged heads, shall be similarly equipped with insulation attachment devices tackwelded at two points. Spacing shall be approximately 305 mm(12"). 7) Integral drain cooling zones shall be designed to allow satisfactory operation with a minimum level variation of condensate in the heater shell for both normal and abnormal conditions. On all heaters with integral drain coolers, a separate high level drain outlet bypassing the drain cooler section located in the condensing section of the heater shell and having at least the same capacity as the normal drain, shall be provided. Separate and independent levelsensing instrumentation connections shall be provided for normal level, high level and emergency high level. The
normal
heater
drain outlet from the drain cooling section shall be sized for the drain flow that occurs with maximum tube side flow. 8) Adequately sized venting orifices for removal of noncondensable gases shall be provided. Air vent limiting orifices for each heater shall be provided and will be installed in the external piping. B.
Channels 1) The channel heads shall be either one of the following three types : hemispherical head; elliptical head; bolted removable cover, full access head at Bidder's option. Channels shall be integral with the tube sheet or welded to the tube sheet.
6.6-33 KHABAT TPP UNITS 1&2 - VOLUME I
2) Heater channels(except for flat plate bolted cover type) shall be equipped with minimum 457 mm(18") ID circular manways, or elliptical manways with a minimum of 457 mm(18") ID major axis. Channel heads shall be of such configuration as to permit plugging of any tube without removing the entire head. C.
Tubes 1) Minimum allowable tube size shall be 15.88 mm(5/8") OD, and average wall thickness 20 BWG for U-tube type LP heaters. 2) Tubes for heaters and drain cooler shall be rolled into carbon steel tube sheets and shall be fabricated of ASTM A688 Type 304L. The Ubend portion of these heaters tubes shall be solution annealed after bending and cleaning in accordance with ASTM A688. 3) Tube plugging, following hydrotest due to tube failure during hydrotest and when location is either inaccessible or impractical for replacement as permitted by the HEI Standard, shall not compromise heater performance. The Bidder shall state the maximum percentage of tubes that can be plugged and still meet the specified heater thermal performance conditions. 4) All internal tube side heater surfaces will be chemically cleaned in the field prior to operation. The Bidder shall recommend the suitable cleaning solution. The heaters shall be designed for exposure to this solution, ease of flushing and cleanout of residue.
D.
Tube Sheets Low pressure heater tube sheets shall be ultrasonically tested to ASTM A-435 requirements.
E.
Tube Support Plates and Baffles 1) Tube support plates shall be spaced to prevent vibration induced damage to tubes during all operating conditions. 2) Support plate tube holes shall be deburred, with edges "broken"(or slightly chamfered) on both sides. 3) Larger diameter tube bundles shall be provided with support plates, or their equivalent, at the U-bends. 4) Impingement baffles of stainless steel shall be provided opposite all nozzle connections where impingement of steam or water might cause erosion of tubes. Baffles shall be designed to preclude transmission of vibration to the tubes and also to protect the tube 6.6-34 KHABAT TPP UNITS 1&2 - VOLUME I
bundle from rebound. Where necessary all impingement baffles shall be attached to the shell or appropriate parts with full penetration welds and liquid penetrant tested in accordance with Appendix VIII of ASME B & PV Code SEC. VIII. F.
Connections 1) In addition to the normal connections provided for steam inlet, drains, vents, feedwater inlet and outlet, the heaters shall be provided with connections for level controls, level alarms and indicators, chemical cleaning,
pressure
and
temperature
instrumentation,
nitrogen
blanketing, HEI and ASME test taps as required. 2) All connections shall be oriented radially and all connections for heaters except for the shell side safety relief valves, acid cleaning nozzle shall be welded. Connections 65mm(2-1/2") and larger shall be butt welded unless this specification states otherwise. Connections 50mm(2") and smaller shall be socket welded. 3) The shell side safety relief valve connections shall be flanged. The tube side safety relief valve connections shall be socket-welded type. 4) The incoming drain connection to heaters shall be on horizontal center line at the U-bend end, beyond the tube bundle. Stainless steel baffles shall be provided to protect the U-bend in the flash chamber. The incoming drain part of No. 1 heater shall be designed to drain enough and prevent from vibration, etc. in the condenser. 5) All connections shall extend beyond the insulation thickness. G. Accessories 1) The Bidder shall size a connection and provide a heavy duty thermal relief valve to protect the tube side of the feedwater heaters and external drain coolers. Valve size, type, and material shall comply with ASME and HEI Code requirements. 2) Safety relief valves shall be shop tested, set and tagged. The minimum tag information shall include identification number, set pressure and accumulation. The set pressure of valves shall be adjustable, without causing damage to the setting surface. H.
Materials All materials used in constructing the equipment to be furnished, but which are not specifically indicated in this specification, shall conform to HEI requirements, shall be the most suitable for the service intended. 6.6-35 KHABAT TPP UNITS 1&2 - VOLUME I
1) Carbon steel plate : ASTM A-516 Grade 70, ASTM A-283 Grade C for pressure containing parts, ASTM A-36 for nonpressure containing parts. 2) Carbon steel forgings : ASTM A-105 Grade II, ASTM A-266 Class 2 or ASTM A-350 Grade LF2, LF3 or equivalent. 3) Tubes : ASTM A688 Type 304L 4) Impingement plates : ASTM A-240 Type 304L and minimum 4.8 mm thickness. Internal impingement baffles in drains discharging into the shell shall be austenitic stainless steel. 5) Nozzles : ASTM A-106 Grade B or A-335 Grade P11 for all heaters. 6) Nozzle Liners : Fabricated stainless steel in accordance with ASTM A-240 Type 304, with a maximum carbon content of 0.03 percent. 7) Orifice plates : ASTM A240 Type 316L 8) Gaskets : Non-asbestos 9) The use of copper alloys in any part of the units is not acceptable. 10) Insulating shroud for heaters No. 1 shall be ASTM A-240 Type 304 stainless steel, minimum thickness 1.6mm. I.
Manufacture 1) Shop Assembly The feedwater heaters shall be completely assembled in the Bidder's shop for shipment to the field in one section. 2) Welding a) All welding, welding procedure qualifications, electrodes, preheat and postweld heat treatment, and welder performance tests shall be in accordance with ASME Section VIII and IX . b) Defects that require repair by welding shall be repaired in accordance with ASME Section VIII. A detailed repair procedure shall state the nature and location of the defect, method of repair, welding
and
nondestructive
examination
procedures,
and
subsequent heat treatment. 6.6.6
Condenser Vacuum Pumps
6.6.6.1
Design of condition A.
The condenser vacuum pumps will be used for initial evacuation of condenser and for continuous removal of noncondensibles from the condenser when it is operating at normal vacuum. The waterbox vacuum 6.6-36 KHABAT TPP UNITS 1&2 - VOLUME I
pumps will be used to remove gases separated at both inlet and outlet waterboxes of the condenser. B.
Start-up or hogging 1) During hogging operation, one(1) vacuum pumps are in operation evacuating the system from atmospheric pressure to 340mbar in 25 minutes. 2) Two(2) vacuum pumps will have to be operated to reduce the hogging time, any further.
C.
Normal (Holding) operation 1) During normal plant operation, one (1×100%) capacity condenser vacuum pumps will continuously remove the non-condensible gases to maintain the 92.5mm HgA condenser vacuum condition. 2) The air in leakage to the condenser is continuously monitored by the rotameter for leakage measurement.
D.
Abnormal operation In the event of excessive air in-leakage to the condenser, or when the dissolved oxygen level of condensate leaving the hotwell is too high, the standby vacuum pump can be activated automatically.
E.
The condenser vacuum pumps shall be sized for initial evacuation of the condenser and turbine in 25 minutes (hogging) and for continuous removal of noncondensable gases(holding) from the condenser in accordance with HEI Standards.
F.
The condenser vacuum pump data sheets will be included in technical bid form. The data contained in these sheets shall be incorporated in the equipment design.
G. The equipment shall be designed for continuous use and shall be capable of handling gases, entrained droplets and water vapor and slugs of water carried over from the condenser. 6.6.6.2
Performance The Bidder shall design that the supplied apparatus will operate quietly without undue vibration and noise, overheat and physical damage under the conditions outlined herein, that the apparatus will be capable of continuous and satisfactory operation supported on the proposed structure under all specified conditions of operation outlined herein, that mechanical vacuum pumps performance will comply with all requirements outlined herein. A.
Holding capacity at design suction pressure 6.6-37 KHABAT TPP UNITS 1&2 - VOLUME I
1) Dry air 2) Water vapor
6.6.6.3
B.
Evacuation time required.
C.
Maximum(Peak) shaft horsepower required.
Design features A.
100% capacity condenser vacuum pumps shall be provided for each unit.
B.
The condenser vacuum pumps shall be of the manufacturer's standard design, shall perform as specified in Paragraph 6.6.7.1 and shall meet the requirements of the HEI Standards for Steam Surface Condensers.
C.
The equipment shall be capable of withstanding forces resulting from all conditions of steady state and transient conditions which may occur during preliminary and routine startup and the normal continuous operation.
D.
The condenser vacuum pumps shall be capable of completely automated operation throughout both the hogging and holding ranges. In addition, they shall automatically transfer to the holding phase on completion of hogging, or from the holding to the hogging phase in the event of excessive air leakage into the condenser.
E.
Construction 1) The vacuum pumps shall be the liquid ring type and each pump and driver shall be mounted on a common fabricated steel base plate. 2) All vacuum pump heat exchangers shall be TEMA Class R and shall be constructed in accordance with ASME Section Ⅷ, Division 1. The heat exchanger shall be furnished of size and capacity to cool the water for their respective vacuum pumps. Each heat exchanger shall be furnished complete with all necessary control and appurtenances required. 3) The equipment shall be furnished with vents and drains to completely drain the equipment. 4) The Bidder shall include an air-water separator to retain the water and release the air to the ventilating system. 5) A Y-strainer shall be provided downstream of the seal water recirculation pump, or at the inlet from an exterior seal water source. 6) A level control valve shall be furnished to control the flow of make-up water to the seal water reservoir.
6.6-38 KHABAT TPP UNITS 1&2 - VOLUME I
7) External connections to the equipment (vacuum pump, water separator, seal water recirculation pump and heat exchanger, air ejector(if required)) shall be flanged. F.
All piping shall comply with the following : 1) Connections 65 mm and larger shall have flanged ends and shall be in accordance with ASME B16.5. 2) Connections 50 mm and smaller shall have socket-welding or thread ends and shall be in accordance with ASME B16.11.
G. The speed changer, if required, shall be of the industrial heavy duty type in conformance with American Gear Manufacturers Association(AGMA) standards with appropriate service factors for pump service. Gears shall be capable of continuous operation. Gear housing shall be totally enclosed with effective shaft seals to prevent oil leakage and entrance of moisture. H.
Coupling guards shall cover all moving external parts of the drive system and comply with OSHA standards.
I.
Materials 1) All materials used in construction the equipment shall be the best suitable for the specified service. The Bidder shall guarantee their use to be suitable for the service intended. 2) Materials for the mechanical vacuum pumps shall be as specified below (ASTM designation). a) Body : ASTM A48 GRADE 30 or EQ.(CAST IRON) b) Head : ASTM A48 GRADE 30 or EQ. c) Rotor : ASTM A536 or EQ.(DUCTILE CAST IRON) d) Ported cone/Plate : ASTM A48 GRADE 30 or EQ. e) Shaft : ASTM A576-1045 or EQ. f) Base plate : ASTM A283 GRADE D or EQ. (CARBON STEEL PLATE) g) Separator : ASTM A283 GRADE D or EQ. h) Silencer : ASTM A283 GRADE D or EQ
6.6-39 KHABAT TPP UNITS 1&2 - VOLUME I
6.6.7
Instrumentation And Controls A.
The Bidder shall design and supply all instrumentation and controls so as to insure accurate, safe and reliable operation under conditions of service.
B.
The Bidder shall design the condenser and condensate system to be started, stopped, controlled and monitored through the Plant PCS.
C.
The function for automatic startup and shutdown of the condenser and condensate system shall be considered in order to minimize operator intervention. All control equipment shall be capable of manual operation through the plant PCS.
D.
Two redundant instruments for system shall be supplied for following applications as a minimum. 1) Heater Level Transmitter : 2/heater 2) Condenser hotwell level transmitter : 2 3) COP discharge pressure transmitter : 2 4) Spray water pressure switch for LP Bypass attemperator : 2 5) Condenser vacuum pressure transmitter : 2
E.
The Bidder shall provide designated instrument type for the following BOP process. 1) LP heaters and hotwell level transmitter: displacement type 2) LP heater level gauge : magnetic type 3) Condenser makeup water, COP discharge, deaerator inlet flow transmitter : ultrasonic type(clamp on, accuracy: 1%)
6.6-40 KHABAT TPP UNITS 1&2 - VOLUME I
6.7
Feedwater System
6.7.1
System descrption
6.7.1.1 The feedwater system delivers heated feedwater, utilizing extraction steam for regenerative heating, from the feedwater storage tank to the steam generator at the required flow rate, temperature and pressure. A secondary function is to deliver water for superheater and reheater desuperheating, HP and LP bypass valve desuperheating, process steam desuperheating and other system when required for steam temperature control. 6.7.1.2 Feedwater system shall consist of the following equipment between the deaerator and feedwater storage tank outlet and the economizer inlet including all branches concerned with feed pump discharge pressure.
6.7.2
A.
One deaerator with feedwater storage tank (No. 4)
B.
Two feedwater pumps and motors
C.
Three high pressure feedwater heaters (No. 5, 6, 7)
D.
Minimum flow recirculation piping with control valves.
E.
Sampling for water analysis
F.
All associated piping, valves, instrumentation and controls
System design criteria
6.7.2.1 Feedwater system shall be designed for the flow based on the operation with turbine control valves wide open (VWO). 6.7.2.2 Hydrazine and ammonia are injected into the suction side of boiler feed pump. 6.7.2.3 Each pump draws suction from the feedwater storage tank for stable and simple operation of feedwater system. 6.7.2.4 For each pump, individual minimum flow line to feedwater storage tank shall be used to avoid overheating and unstable condition of pump, and flow meter shall control individual modulating control valve in recirculation line to feedwater storage tank. Minimum flow quantity will be determined by feedwater pump manufacturer. 6.7.2.5 During normal plant operation, warm water is supplied from the discharge lines of each feedwater pump in service to warm up the pump not in service so that water hammering and thermal shock shall be prevented when the pump is started.
6.7-1 KHABAT TPP UNITS 1&2 - VOLUME I
6.7.2.6 Sample for feedwater analysis will be extracted from the feedwater pump discharge header and economizer inlet. 6.7.2.7
Start-up A.
The demi water storage tanks will feed the 1 x 100% demi water transfer pump and this pump shall supply the make-up water requirements of the deaerators. Any upsurge from excess water will be routed to the drains system.
B.
Feedwater storage tank should be filled enough to operate the system before normal start-up of the system and warmed up by proper manner.
C.
Manually operated valves, such as feedwater pump suction shutoff valves, isolation valves in minimum flow recirculation line and feedwater pump balance leak-off valves which, if inadvertently closed during operation and would damage the pumps, shall be in a "locked-open" position.
D.
During cold start, feedwater system shall be cleaned with condensate and promote the removal of dissolved Oxygen and the deaerating. During hot restart, aux. steam should be supplied to maintain the feedwater temperature at the saturation temperature corresponding to deaerator pressure. Low temperature feedwater causes thermal fatigue when passed through the HP feedwater heater.
E.
During start-up and low load operation, feedwater temperature should be maintained at the temperature of deaerator by supplying the steam for feedwater heating from aux. steam header to deaerator. By this method, it should be possible to fill the steam generator with hot feedwater when the steam generator is on standby for hot restart.
F.
During start-up and low load operation, the flow should be recirculated to the feedwater storage tank through the minimum flow control valve to avoid overheating of feedwater pump and to avoid the unstable system condition due to the flow in the feedwater system being less than minimum flow requirements of the pump.
6.7.2.8 Normal operation A.
Boiler feedwater pumps and all H.P feedwater heaters should be used during normal operation. Feedwater pumps shall be controlled by the signal difference between feedwater flow corresponding to steam generator demand signal and measured feedwater flow. 6.7-2 KHABAT TPP UNITS 1&2 - VOLUME I
B.
Desuperheating water for superheat and reheat steam shall be supplied by individual steam temperature control.
6.7.2.9 Component description 6.7.2.9.1 Deaerator and feed water storage tank A. Quantity
: One (1)×100% capacity
B. Design performance
: Based on VWO condition
C. Design capacity
: The reserved capacity based on normal water level shall be possible to operate during min. 7 minutes
D. Design pressure
: The Sum of 115% of extraction pressure from VWO condition
E. Design temperature
: Maximum extraction steam temperature or pegging aux. steam temperature, which is greater
F. Type
: Horizontal
6.7.2.9.2 Boiler feedwater pump A. A.
Quantity Type
B. Design capacity
: Two (2)×100% capacity : Horizontal, Centrifugal, Multi-stage, Motor- driven : Flow for Boiler feeding plus 5% surge margin and 6% wear margin
C. Design head
: Based on required system head plus head margin corresponding to 5% flow surge margin.
D. NPSHav
:
Based
on
the
result
of
deaerator
decay
calculation 6.7.2.9.3 H.P heaters A.
Quantity
: Each One (1)× 100% capacity
B.
Design performance
: Based on VWO condition
C.
Design pressure 1) Tube
: 1.05 × (1.06 × Boiler Design Pressure + friction drop from No.5 HP heater to Boiler) or 1.05 × Pump discharge pressure at shutoff , whichever is greater
2) Shell
: Full vacuum and 115% of extraction pressure from VWO condition
6.7-3 KHABAT TPP UNITS 1&2 - VOLUME I
3) Design temperature for shell and tube : Per HEI standards, and the requirements for desuperheating section should be taken into consideration. D.
Tube material
:
ASTM A-213, type 304N or equal
E.
Type
:
Horizontal, U-tube
6.7.2.9.4 Piping A.
General Feedwater piping shall be from the deaerator outlet to the steam generator economizer inlet, divided into feedwater suction and feedwater discharge. Transient analysis required for suction piping for turbine trip condition.
B.
Design parameters
:
1) Suction Piping a) Pressure
:
Full vacuum and deaerator design pressure plus static head.
b) Temperature
:
Saturated temperature at 115% of deaerator
pressure
from
VWO
conditions. 2) Discharge piping a) Pressure : -
Upstream of feedwater pump flow control valve : 1.05 × Pump discharge pressure at shutoff
-
Downstream of feedwater pump flow control valve
:
1.25 × Boiler design pressure or Boiler design pressure + 225 psig, whichever is lesser b) Temperature : Last feedwater heater outlet temperature at 115% of HP extraction steam pressure for the last feedwater heater c) Piping sizing : 50mm-175mm ; for maximum velocity limit of 4.6m/s(50mm) and 7.3m/s (175mm)
above 175 mm ; for
maximum velocity limit of 7.3m/s d) Bypasses : Bypass pipeline including bypass valve for high pressure heaters shall be sized for the same pressure drop as the total pressure drop in the heater and in the portions of the main feedwater piping between the points of takeoff and return of the 6.7-4 KHABAT TPP UNITS 1&2 - VOLUME I
bypass pipeline. The maximum allowable velocity in the bypass pipeline may exceed the optimum value for pipe sizing 6.7.3
Deaerator and storage tank
6.7.3.1 Design condition 6.7.3.1.1 The power plant shall be designed to accept the load variations at a minimum rate of 5% of MGR per minute between 50% MGR and MGR, and 3% of MGR per minute between 30% and 50% MGR and also transient condition from turbine or steam generator unit trips. Supports for the deaerators shall be capable of withstanding the loads and moments calculated by the Bidder in addition to normal loads and moments and shall provide for transfer of loads to building structure by positive means. 6.7.3.1.2 The deaerator and feedwater tank shall be designed for quietness of operation and minimum vibration at all rates up to and including its maximum capacity, during rapid load changes and with the temperature of entering feedwater ranging from steady state to normal condenser hotwell temperature. The deaerator shall be capable of furnishing deaerated water continuously at the feedwater tank outlet at any rate from 10 to 100 percent of steady state maximum flow with a residual oxygen content not to exceed 7 ppb. The deaerated water shall be heated to the saturation temperature corresponding to the steam pressure maintained in the shell. Over the entire load range, the free carbon dioxide content shall be reduced to zero. 6.7.3.1.3 Feedwater Oxygen content, measured at the Feedwater storage tank outlet to boiler feed pump suction, shall not exceed 7 ppb and free carbon dioxide content shall be zero when the deaerator is operating 6.7.3.1.4 All components and component parts shall be designed so that safe working stresses are not exceeded during all modes of operation such as startup, steady state at any load from zero to full load, transient conditions, and forces caused by flashing of the liquid in the storage tank. The trays, tray enclosure, and support members shall be designed to withstand the maximum pressure differential across the trays and tray enclosure during any mode of operation. Among these modes, the Bidder shall consider the transient condition occurring upon sudden load rejection. For this condition it shall be assumed that all steam flow has stopped while condensate is still entering the deaerator at the maximum flow rate, for transient or condensate control valve failed wide open, resulting in a pressure differential across the 6.7-5 KHABAT TPP UNITS 1&2 - VOLUME I
tray enclosure. 6.7.3.1.5 The tray enclosure, either separate or combined with the vent condenser, shall preferably be bolted and not welded directly to the deaerator pressure vessel shell. Supports for the enclosure shall be of bolted design. Bolts shall be welded to one of the mating parts. After completion of assembly, all nuts shall be tightened and tack welded to the bolts. The entire internal structure shall be constructed to provide a limited freedom of movement through the use of bolted joints to eliminate residual stresses from welding, to mitigate thermal stress, and to promote damping of vibration. 6.7.3.1.6 The non-hydraulic loads that can be transmitted to nozzles by piping are not less than those which will cause a stress in the nozzle at the field welding joint. The Bidder's design shall be of such strength in the shell and in the nozzle that at no location will the combined load and internal design pressure result in a stress exceeding 90 percent of the ASME minimum yield strength. 6.7.3.1.7 The downcomers and equalizers shall accommodate the drainage of the heater section to the storage section under all modes of operation and particularly during transient conditions. Specifically the downcomers and equalizers shall be sized so that during a transient condition, except for an instantaneous and momentary condition, the flow of condensate through the downcomer is downward, and the flow of steam through the equalizer is upward.
The resulting pressure differences between the two vessels shall
be such that the equalizers will not become flooded, and the condensate level in the heater shall not impair the steam flow to the heater. 6.7.3.1.8 The downcomers shall be equipped with heavy deflector hoods to protect the trays against inadvertent upsurges of condensate. The equalizers shall also be equipped with heavy deflector hoods to divert the flow of steam and entrained condensate from the storage tank to the heater, away from the trays. 6.7.3.1.9 Each connecting nozzle between storage tank and heater shall require not more than one field weld. Nozzles shall be aligned in the shop to ensure a correct fit at field assembly. Any refabrication costs required at final field assembly due to shop misalignment shall be borne by the Bidder. 6.7.3.1.10 The spray valves distributing the condensate over the trays shall be designed for concurrent full internal vacuum and full exterior deaerator pressure to withstand the pressure resulting from liquid flashing in the pipe 6.7-6 KHABAT TPP UNITS 1&2 - VOLUME I
before the nozzles or spray holes, opening the control valve that supplies condensate to an empty spray pipe, or filling an empty system. In lines designed for full vacuum, methods may be employed for relieving vacuum. The trays shall be designed to safely withstand the impact energy of the condensate on the trays resulting from the above described pressure peaks. 6.7.3.1.11 Deaerator supports and nozzles shall be suitable to withstand the forces imposed on the deaerator by extraction steam and feedwater piping. Corresponding reactions and moments for these lines will be furnished to the Bidder after award of order. 6.7.3.1.12 The levels of feedwater tank shall be set as follows(shown as % of inner height) : A.
Low low level(for boiler feed pump trip) : 20%
B.
Normal level : 70%
C.
High level : 85%
D.
Overflow level : 89%
E.
High high level : 92%
6.7.3.1.13 The feedwater tank shall hold hot feedwater for min.7 minutes effective storage below the normal water level and above the low low level at V.W.O conditions. The deaerator and feedwater tank shell shall be designed for working pressure from full vacuum to design pressure. 6.7.3.1.14 A 1.6 mm corrosion allowance shall be provided over the calculated thickness for the deaerator shell, the feedwater tank shell, the connecting pipe, and the equalizing lines. 6.7.3.1.15 The deaerator and feedwater tank shall be designed to eliminate water hammer. 6.7.3.1.16 The feedwater outlets from the feedwater tank shall be designed for smooth flow and to prevent the formation of a vortex in the feed water pipe work to the boiler feed pumps. 6.7.3.2 Design Features 6.7.3.2.1 The deaerator shall be designed in accordance with the requirements of ASME Section VIII Div.1 and this specification. The deaerator shall be designed, certified and documented in accordance with the Code. 6.7.3.2.2 The vessels shall be constructed of welded, carbon steel plates. 6.7.3.2.3 Each section of the feedwater tank shall be designed to withstand the dead weight of the deaerating heater section when the deaerating heater section is placed on the upper half of the storage section during field installation. 6.7-7 KHABAT TPP UNITS 1&2 - VOLUME I
6.7.3.2.4 Tray Banks and Spray Nozzles A sufficient number of tray banks shall be assembled in the deaerator to demonstrate fit up before shipment. The banks shall be removed and shipped separately for field installation. All trays shall be self-draining. Trays shall be securely held in place, and deflectors shall be provided to protect the trays from direct impingement of steam and water entering the deaerator and from flash steam from the feedwater tank. Adequate spacing shall be provided between inlet fluid connections and deaerating components to prevent damage due to transient conditions, flashing, or high velocities. Spray nozzles shall be positively locked in place so as to prevent being dislodged under any and all operating conditions contained in this Specification. 6.7.3.2.5 Vent Condenser The vent condenser shall be capable of preventing undue loss of steam through the vent connection under all conditions of operation. 6.7.3.2.6 Impingement Baffles All steam inlet impingement baffles and their support shall be designed to withstand all forces resulting from an occasional water slug. 6.7.3.2.7 Manholes All necessary manholes and access doors for the deaerator and feedwater tank shall be provided. Manholes shall not be smaller than 600 mm I.D and shall be of adequate size to allow removal of all internal assemblies. 6.7.3.2.8 Screen (pump suction nozzle startup screen) A screen shall be installed at the pump suction nozzles of the feedwater tank. This screen will be removed after pre-operation. The screen shall be fabricated from stainless steel material. The opening shall be 60 mesh screen. This screen shall be removed through the tank manhole for flushing. 6.7.3.2.9 Steam inlet connections Steam inlet connections shall be located to provide a nearly uniform steam flow over the entire tray area. External or internal steam distribution pipe headers or internal baffles shall be provided to direct the flow to the tray face area. All nozzles distributing steam shall be on or symmetrically arranged about the midpoint of the deaerator vessel. 6.7.3.2.10 Tank drains Deaerator and feedwater tank drains shall be located to flush with the bottom of tank so that complete drainage can be assured. 6.7-8 KHABAT TPP UNITS 1&2 - VOLUME I
6.7.3.2.11 Pump suction nozzles Pump suction nozzles shall extend 75 mm up from the bottom of the feedwater tank section with a vortex breaker. Provisions shall be made, including suitable connections, to completely drain the deaerator and feedwater tank. The vortex breaker and suction nozzle entrance shall create minimum resistance. 6.7.3.2.12 Feedwater pump recirculation nozzles Boiler feed pump minimum flow recirculation nozzles shall have internal sparger pipe located above the feedwater tank water level. The sparger pipe shall have drilled holes with a max. allowable pressure drop in the feedwater tank, and the total area of the holes shall be at least three times the nozzle area. Special care shall be given to prevent steam dragging into the feed pump suction lines due to vortex formation by the high velocity water leaving the recirculation lines. 6.7.3.2.13 Safety relief valves Safety relief valves which are required for overpressure protection shall be sized in accordance with ASME Code, Section VIII, and shall be provided by the Bidder. Flanged safety relief-valve connections shall be sized and provided by the Bidder as required. Safety relief-valve discharge will be to atmospheric drains. The Bidder shall provide data for the proposed safety relief valves. Sizing of the deaerator safety relief valve shall be based on the following condition : - Auxiliary steam control valve failing open during control valve failure, the condensate flow entering and leaving the deaerator is assumed to be zero. Quantity of safety relief valve shall be determined by the Bidder. 6.7.3.2.14 Materials A.
Materials for pressure boundary applications shall conform to the requirements of ASME Code, Section VIII or ANSI Code B31.1 as applicable. Material for parts not specified shall be subject to KNOC's acceptance. Material certifications of critical component materials shall be furnished to KNOC.
B.
Materials for the deaerator, feedwater tank, and related components shall be as specified below. Where materials is not specified it shall be selected by the Bidder. Stainless steel materials shall be used for the appropriate internal parts or components of the deaerator including all 6.7-9 KHABAT TPP UNITS 1&2 - VOLUME I
areas from the point where the steam and water mix to the point where non-condensable gases are separated and vented through the vent condensing system. 1) Deaerator shell and feedwater tank shell - ASTM A285 Grade C, ASTM A516 Grade 70. 2) Spray valves and orifice plates - Spray valves
: Stainless Steel Type 316
- Orifice plates
: A240 Type 304L
3) Trays - ASTM A240 Type 430. 4) Tray stack enclosure, vent condenser enclosure and vent pipes, and distributing troughs(above tray stack) - ASTM A240 Type 304L 5) Impingement baffles - ASTM A240 Type 304L and minimum thickness 6mm 6) Piping - Size 600mm(N.D) and smaller : ASTM A106 Grade B - Size larger than 650mm(N.D) : ASTM A516 Grade 70 or equiv. 7) Nozzles(connections) - ASTM A105, ASTM A216. 8) Internal bolts, studs, and nuts - Bolts and studs : - ASTM A193 Type 304 - Nuts : ASTM A194 Type 304 9) Safety relief valve - Body & bonnet : - ASTM A216 Grade WCB or WCC 10) Flange - ASTM A181 Class 60 or 70. 11) Gaskets - Metal 12) Permanent support saddles(for the deaerator and feedwater tank) - ASTM A36, A283 Grade C or same as shell material. 6.7.3.2.15 Load criteria A.
Loads due to turbine trip (sudden load rejection) with condensate control valve wide open.
6.7-10 KHABAT TPP UNITS 1&2 - VOLUME I
B.
Equipment shall be designed for the seismic conditions given in Volume 2, Technical Schedule, Schedule A, Site Particulars. Seismic accelerations need not be combined with loads caused by transients.
C.
Internal temperature differentials as defined by the Bidder.
D.
Dead weight
E.
Other loads as determined to be critical by the Bidder.
6.7.3.2.16 Manufacture A.
Surface preparation All parts of the equipment shall be thoroughly cleaned of all mill scale, rust, grease and other foreign matter and the exterior surfaces shall be given one coat of inorganic zinc paint as specified. Interior of shells shall be thoroughly cleaned by using wire brushing so as to leave clean metal surfaces exposed. Inside surfaces shall not be painted or coated, unless otherwise specified. Accessories shall be painted with a "shop coat" of manufacturer's standard paint suitable for the service. No asphaltum paint shall be used. Before shipment, all exposed machined surfaces shall be coated with a suitable grease or anti-rust compound.
Before shipment, inlets and
outlets shall be blanked off or plugged. B.
The other manufacture requirements for deaerator and feedwater storage tank is same as that of LP heaters. Refer to LP heater's section
6.7.4
Boiler feed pumps
6.7.4.1 Design conditions 6.7.4.1.1 The boiler feed pumps shall be designed to ensure continuous, safe and economical operation providing the maximum reliability and without undue heating, vibration or noise. 6.7.4.1.2 Operational requirements A. The boiler feed pump head-capacity curve shall be continuously rising from maximum flow to shutoff. The pump shutoff head shall be no more than 20 to 30 percent higher than the total differential head(TDH) at the design point allowing for tolerances. The pressure pulsation shall be no more than 3% of the head produced by one pump stage (not whole pump TDH) as measured on the pump discharge. 6.7-11 KHABAT TPP UNITS 1&2 - VOLUME I
B. The boiler feed pumps shall be capable of operating continuously at any rate from minimum flow to rated flow under all normal conditions without cavitation or undue noise or vibration. The boiler feed pumps will be required to operate at minimum flow for extended periods. The Bidder shall indicate the minimum flow for continuous operation. C. Under severe transient conditions, the boiler feed pumps may
be
momentarily subject to moderately cavitation conditions. D. The boiler feed pumps at the rated speed shall not exceed the vibration and shaft movements specified hereinafter. The maximum vibration, as measured on the boiler feed pump shaft adjacent to all bearings, shall not exceed 42 microns double amplitude throughout the load range. The maximum vibration as measured on the boiler feed pump bearing pedestals, shall not exceed 21 microns double amplitude throughout the load range. Shaft movement in either axial direction shall not exceed 0.3 mm when measured from the center of the thrust gage clearance. The boiler feed pumps shall have a head capacity characteristic that will ensure satisfactory parallel operation of the pumps at any flow from minimum flow to run-out condition, with any combination of operating pumps. E. The boiler feed pump shall be capable of 'dry running', and of accepting a complete loss of water. In such an extreme case, it is recognized that the pump should be tripped and restarted after it has been reprimed. The pump must, however, be capable of being tripped and brought to restart safely in a short time. F. The pumps shall be designed for continuous unattended service while operating within the limits of the operating range, including runout and minimum flow. Maximum thermal shock is expected to occur on a complete loss of main turbine-generator load with resultant rapid feedwater temperature reduction from design temperature to "cold water" conditions at runout flow. G. The stand-by pump shall be capable of fast start to prevent load runback. H. Reheater attemperation water will be taken from the interstage of boiler feed pump.
6.7-12 KHABAT TPP UNITS 1&2 - VOLUME I
I.
The boiler feed pump shall be selected so that the best efficiency point occurs at the design point
J. The first critical speed of each pump shall exceed the operating speed of the pump by at least 25 percent. 6.7.4.2 Design and construction features 6.7.4.2.1 General A. The boiler feed pumps shall be the horizontal, centrifugal, double suction, barrel type, complete with all specified and required accessories for a complete installation B. The radial clearance between the diffuser vane or volute tongue and the periphery of the impeller blade shall be at least 3 percent of the maximum impeller blade tip radius for diffuser designs and at least 6 percent of the maximum impeller blade tip radius for volute designs. C. Running clearance shall meet the requirements of API 610 para 2.6.6. 6.7.4.2.2 Baseplate Baseplates shall be of fabricated steel with grout holes. They shall extend completely under all parts of the pump and accessories, and shall be positive slope drain rim type with the flat portion of the plate sloping continuously toward a drain connection at one end. The boiler feed pump and the common motor driver shall be provided with one pieces of baseplate. 6.7.4.2.3 Casing A. The outer casing shall be of forged low carbon steel.
Areas around the
discharge exit and at the seals shall be surfaced with an overlay of a metal alloy to resist erosion and corrosion. The inner casing cored water passages shall be machined or finished to smooth surfaces. The suction and discharge nozzles of the boiler feed pumps shall project upward from the pump casing. Design stress levels in the barrel, head, and bolting of the boiler feed pump shall not exceed the limits of the ASME Code for Pressure Vessels, Section VIII, or equivalent. Welding shall be in accordance with ASME Section VIII, IX or equivalent. B. Casing wear rings shall be of groove or serrated type and of hardened stainless steel alloy that will be compatible with the impeller material, will result in prolonged life, and will be free of galling tendencies. The ring shall be rigidly positioned to prevent rotation under any conditions of operation. Impeller wear rings shall not be acceptable. 6.7-13 KHABAT TPP UNITS 1&2 - VOLUME I
6.7.4.2.4 Impellers and diffusers A. Impellers shall be the single suction enclosed type, except the first stage which may be double suction. All surfaces shall be machined or hand finished to a smooth surface. Impellers shall be keyed and individually positioned on the shaft. Each impeller shall be statically balanced after completion of all machining and rebalanced after any alteration. After assembly, the complete rotating element shall be dynamically balanced. B. If the Bidder proposes diffuser type pumps, the Bidder shall propose pumps with enclosed type diffusers (the pumps with cantilever(semienclosed) type diffusers shall not be acceptable). The diffuser design shall be single precision casting where the vanes and shrouds are cast in one piece. Welding and soldering are not acceptable. 6.7.4.2.5 Bearing A. Thrust bearings shall be the tilting pad double action type. B. Sleeve bearings shall include "E" type thermocouples in contact with the bearing metal. Thrust bearings shall include "E" type thermocouples which, if design permits, shall make contact with one of the thrust shoes or shall be placed to give the most direct indication of actual bearing temperature. The Bidder shall submit a detailed description of how this will be accomplished.
Thermocouples shall be brought back to a
common terminal box mounted on the pump frame or off the baseplate of the pump. C. The Bidder shall state the method of measurement that will be used to determine correct balancing of the pump and coupling before shipment. The Bidder shall state the maximum limits of vibration that should be used for alarm and trip points during plant operation. In no case shall these limits exceed HI standards, or equivalent. 6.7.4.2.6 Lube oil system A. The Bidder shall provide a complete common forced feed lube oil system for the bearings of each boiler feed pump and common motor combination including, but not necessarily limited to the following : 1) A complete lube oil system and all associated instrumentation. The reservoir shall have sufficient free volume above the normal operating range level to accommodate full system flowback without bringing in the high level alarm regardless of oil temperature. The Bidder shall furnish and install the following equipment on each oil reservoir. 6.7-14 KHABAT TPP UNITS 1&2 - VOLUME I
a) One(1) shaft driven 100 % capacity main oil pump. b) One(1) AC motor driven 100% capacity auxiliary lube oil pump. c) One(1) 100% lube oil cooler for use with closed cooling water. The oil side of the coolers shall be designed for maximum oil pressure. d) Duplex type oil strainers with differential pressure indicating switch located at the outlet side of the lube oil cooler e) Pressure, flow, temperature, level and other instruments as necessary. f) Three(3) Pressure transmitters for sensing lubricating oil pressure shall be provided for pump start and stop, alarm interlock and trip. B. The auxiliary lube oil pump will be used to prelubricate the pump before starting and shall start automatically in the event of low oil pressure from the operating main lube oil pump. C. Lube oil system piping shall be designed with a minimum number of joints and the inside surfaces shall be essentially crevice free. All piping shall be concealed wherever practicable, and all exposed piping shall be arranged to present a neat appearance. Oil piping shall be welded steel, thoroughly cleaned, pickled and flushed.
Pipe ends shall be suitably
capped to prevent the entrance of dirt and moisture. Valves shall be forged steel and of an approved make with bronze bodies. Sight flow indicators shall be included for each bearing. 6.7.4.2.7 Shaft, sleeves, seals, and jacket cooling A. The boiler feed pump shafts shall be forged steel, accurately machined and ground, and of adequate size and strength to withstand safely and continuously all stresses resulting from startup, operating and transient conditions to which it will be subjected. The shaft extension shall be tapered to facilitate coupling removal. B. Shaft sleeves and bushings, as required for the proposed shaft seals, shall be of suitably hardened stainless steel materials in accordance with the Bidder's standard construction for the specified service. Materials shall be free of galling tendencies. C. Shaft seals shall be the cartridge mechanical type with pumping ring and external and internal shaft seal cooling water system. Also, shaft seals shall be designed to withstand the vapor lock tests. D. The jacket cooling water will be supplied from the closed cooling water system. 6.7-15 KHABAT TPP UNITS 1&2 - VOLUME I
6.7.4.2.8 Mechanical type seal water system A. The Bidder shall supply a complete shaft seal cooling water system for each pump. The internal system shall consist of shaft seal cooling water cooler, piping, valves, filter and temperature elements for a complete system. B. The shaft seal cooling water system shall, under all conditions of operation, maintain the outflowing seal water temperature sufficiently below 100 deg.C to prevent flashing. No cold injection water shall flow into the pump. C. The shaft seal cooling water will be cooled by the tube side cooling water. D. The shaft seal cooling water system shall include a magnetic separator or filter that will protect the seals from damage due to solids. The screen shall be of type 316 stainless steel, or approved equal, and shall be of a type that is readily cleaned by flushing. The differential pressure indicating switch for indication of a fouled strainer shall be supplied. 6.7.4.2.9 Couplings The coupling for the boiler feed pump shall be the non-lubricating flexible type. Coupling selection shall consider the vibration and thermal conditions. The coupling service factor shall be not less than two(2). 6.7.4.2.10 Strainers. A. Each boiler feed pump shall be provided with one basket strainer. The Bidder shall supply the suitable fine/coarse mesh size for start up and normal operation and the differential pressure indicating transmitter for indication of fouled. The basket strainer type shall be cross type and pressure drop for normal operation at clean condition shall be less than 0.07 kg/cm2. The basket strainer is suitable to be installed in a vertical pipe run. B. The strainer shall be constructed of stainless steel, and 300lb RFWN ANSI flanges. 6.7.4.2.11 Others A. Each pump, when in the stand-by condition, shall be warmed up to the feedwater temperature of the operating pump before being started. If the Bidder has a developed warm-up system which will provide the optimum design, it shall also be offered. The Bidder shall also submit a procedure for prewarming and post6.7-16 KHABAT TPP UNITS 1&2 - VOLUME I
warming after contract. Any instrumentation required for control and monitoring of warming, such as barrel differential temperature measurement, shall be supplied. B. A hydraulic balancing drum shall be capable to operate any condition and furnished with local pressure indicator and additional tap. The axial thrust of the rotor shall be carried by balance drum and external oil lubricated thrust bearing. The Bidder shall provide the pump speed vs balancing drum leak off outlet pressure and tie in point pressure with the balancing drum leak off line (New/worn condition). C. All hot surfaces of the pumps shall be insulated. Insulation shall be in removable sections of sheet metal lagging and shall provide a maximum surface temperature of 55 deg.C. The Bidder shall supply the pump bottom side insulation. D. The flow element, cone type meter, with three(3) flow transmitters shall be provided at each cross over line. E. Prior to chemical cleaning of the system, the pump rotor will be removed and a blanking off plate installed around the openings. The Bidder shall design and furnish the blanking off plates and companion gaskets to insure that when the chemical cleaning fluid is pumped through the pump, no leakage will occur into the pump internals. F. The Bidder shall provide complete reverse rotation senor shall provide dry contact to start oil pump and to close discharge valve when reverse rotating. 6.7.4.3 Electrical and instrumentation requirements 6.7.4.3.1 Drivers A. A common motor driver shall be provided for boiler feed pump. B. Motor rated horsepower shall not be exceeded at the specified pump rating by the impellers selected for the service. The service factor may be used infrequently, but it shall not be exceeded by any operating condition that can be developed by the installed impellers. C. The motor for the boiler feed pump shall endure the stress resulting from the cycling operation and shall be designed and manufactured to maintain high reliability during life expectancy. 6.7.4.3.2 Vibration monitoring devices
6.7-17 KHABAT TPP UNITS 1&2 - VOLUME I
A. The Bidder shall provide the vibration monitoring devices consisting of probes with protective housings, extension cables and transducers with housing for accurate, reliable vibration monitoring. B. The radial vibration probes shall be provided with two probes per bearing positioned radially at 90 degrees (X,Y). The dual axial vibration/position probes and keyphaser shall be provided for each pump. C. The Bidder shall provide complete reverse rotation detector to start oil pump and to close discharge valve when reverse rotating. 6.7.4.4 Manufacture 6.7.4.4.1 Fabrication A. Written welding and heat treatment procedures are to be submitted to KNOC for acceptance prior to use. B. Defects that require repair by welding shall be repaired in accordance with the applicable Code. A detailed repair procedure shall be submitted to KNOC for acceptance prior to performing the repair. The procedure shall state the nature and location of the defect, method of repair, welding and nondestructive examination procedure, and subsequent heat treatment. C. All equipment shall be neatly finished and free of burrs and fins. D. All casting surfaces shall meet visual examination acceptance standards contained in MSS SP-55. Impregnated castings are not acceptable. Repair of faulty castings shall be subject to acceptance by the KNOC. E. Interior surfaces shall be thoroughly cleaned of all mill scale, cuttings, oil, weld spatter, and other foreign matter. 6.7.4.4.2 Materials A. For the specific materials identified in the following list, the base bid shall be predicated on their use and guaranteed by the Bidder to be suitable for the service intended. The Bidder may bid alternative materials of equal or superior properties for KNOC's consideration. B. Materials for the pumps shall be as specified below (ASTM Designation) 1) Outer casing, Barrel
Forged 0.25% Carbon Steel with Overlay of Stainless Steel.(A105or Equivalent)
2) Inner casing or Volute 13% Chrome Stainless Steel (A743 Grade CA6NMor Equivalent) 3) Impellers
13% Chrome Stainless Steel 6.7-18 KHABAT TPP UNITS 1&2 - VOLUME I
(A743 Grade CA6NMor Equivalent) 4) Shaft
13% Chrome Stainless Steel (A276 Type410 or Equivalent)
C. The Bidder shall identify the materials used at all interface connections and on major parts as to the ASTM Specifications, or equivalent code. 6.7.5
High pressure feedwater heaters
6.7.5.1 Design condition 6.7.5.1.1 Type of Feedwater Heater All feedwater heaters shall be of the horizontal shell and U-tube design with integral drain cooling zones. The high pressure heaters shall also be equipped with integral desuperheating zones. 6.7.5.1.2 Tubeside velocity The maximum water velocity through the tube shall be in accordance with the Heat Exchange Institute Standard at the normal full load operating conditions and shall not exceed 3 m/sec(10 ft/sec). 6.7.5.1.3 Temperature changes The feedwater heaters shall be designed to ensure continuous, safe and economical operation providing the maximum reliability under the instantaneous temperature drop from normal condition inlet temperature to saturated temperature corresponding to deaerator pegging steam set pressure and to endure the inlet temperature changes on various load change cycles. 6.7.5.1.4 Nozzle and support loads Supports for the feedwater heaters shall be capable of withstanding the loads and moments calculated by the Bidder in addition to normal loads and moments and shall provide for transfer of loads to building structure by positive means. 6.7.5.1.5 Overload and abnormal conditions A. The feedwater heaters shall be capable of operating at the overload and abnormal conditions as specified below without malfunction or damage to the heaters. The Bidder shall determine the effects of removing heaters from service and provide for those effects in the heater designs. 6.7-19 KHABAT TPP UNITS 1&2 - VOLUME I
The Bidder shall supply calculations and complete Technical Data form for abnormal conditions in bid data form. B. Abnormal condition occurs when heaters are bypassed. Extraction steam flows and drain flows of heaters in service proportionally increase, based on heater performance, over design flows. Extraction steam pressure will be increased. 6.7.5.1.6 The Bidder shall perform a life time cycle fatigue analysis for the high pressure heaters based on all conditions and the unit mode of operation. The cycle service life for the following conditions shall be determined: - Hot start and regular shutdown - Warm start and regular shutdown - Cold start and regular shutdown - Turbine trip and hot restart 6.7.5.2 Performance requirements The Bidder shall design that all equipment and materials will comply with all applicable code. The following performance of each feedwater heater shall be specifically satisfied. A. Terminal temperature difference B. Drain cooler approach C. Tube side pressure drop D. Shellside pressure drop 6.7.5.2.1 Performance in accordance with all specified conditions without excessive noise and vibration, overheating or physical damage to the equipment. The heaters shall be operable under the rapid starting or load changing conditions without any limitation. 6.7.5.3 Design features 6.7.5.3.1 The feedwater heaters shall be designed in accordance with the requirements of ASME Section VIII, HEI standards and this specification. The feedwater heaters shall conform to ASME Section VIII Division 1 rules and the fatigue analysis for high pressure heaters shall conform to Division 2 rules. The feedwater heaters shall be designed, certified and documented in accordance with code. 6.7.5.3.2 Shells A. The high pressure heaters 5, 6 & 7 shall have removable shells.
6.7-20 KHABAT TPP UNITS 1&2 - VOLUME I
B. Feedwater heaters shall be equipped with fixed supports at the channel and wheels or roller supports for the removable portion of the shell. C. All heaters shall have welded shell-to-tube sheet or shell- to-shell skirt joints. Shell covers shall be welded to the shells. Feedwater heaters with welded shell-to-tube sheet or shell-to-shell skirt joints shall be provided with a cutting line. Cutting lines shall be clearly indicated on the heater shells and cutting line location shall be shown on Bidder's drawings. A minimum 200 mm(8") wide stainless steel flame protecting band shall be provided around the tube bundle beneath the shell cutting line. D. A shell corrosion allowance of 1.6 mm(1/16") minimum shall be used. E. Lifting and pulling lugs shall be furnished with each heater. All lifting lugs shall be adequately sized for the empty weight of the heater. F. Integral drain cooling zones shall be designed to allow satisfactory operation with a minimum level variation of condensate in the heater shell for both normal and abnormal conditions. On all heaters with integral drain coolers, a separate high level drain outlet bypassing the drain cooler section located in the condensing section of the heater shell and having at least the same capacity as the normal drain, shall be provided. Separate and independent level-sensing instrumentation connections shall be provided for normal level, high level and emergency high level. The normal heater drain outlet from the drain cooling section shall be sized for the drain flow that occurs with maximum tube side flow. G. Adequately sized venting orifices for removal of noncondensable gases shall be provided. Air vent limiting orifices for each heater shall be provided and will be installed in the external piping. 6.7.5.3.3 Channels A. The channel heads shall be either one of the following three types : hemispherical head; elliptical head; bolted removable cover, full access head at Bidder's option. Channels shall be integral with the tube sheet or welded to the tube sheet. B. Heater channels(except for flat plate bolted cover type) shall be equipped with minimum 457 mm(18") ID circular manways, or elliptical manways with a minimum of 457 mm(18") ID major axis. Channel heads shall be of such configuration as to permit plugging of any tube without removing the entire head. 6.7-21 KHABAT TPP UNITS 1&2 - VOLUME I
6.7.5.3.4 Tubes A. Tubes for heaters 5, 6 & 7 shall be rolled full depth into the tube-sheet and welded to the stainless steel clad tube sheet. The tubes for the high pressure heater shall be ASTM A-213 Type 304N or equivalent. The Ubend portion of these tubes shall be solution annealed after bending and cleaning in accordance with ASTM A688. B. Tube plugging, following hydrotest due to tube failure during hydrotest and when location is either inaccessible or impractical for replacement as permitted by the HEI Standard, shall not compromise heater performance. The Bidder shall state the maximum percentage of tubes that can be plugged and still meet the specified heater thermal performance conditions. C. All internal tube side heater surfaces will be chemically cleaned in the field prior to operation. The Bidder shall recommend the suitable cleaning solution. The heaters shall be designed for exposure to this solution, ease of flushing and cleanout of residue. 6.7.5.3.5 Tube sheets A. High pressure heater tube sheets shall be ultrasonically tested to ASTM A-388 requirements. Tube sheets for the high pressure heater shall be provided with stainless steel cladding. The tube sheet, if forged, shall have been machined sufficiently to remove any skin effect prior to applying the cladding material. The stainless steel cladding shall be applied to the tube sheet by weld overlay in accordance with ASTM A-264. The overlay shall consist of Type 309L stainless steel for first layer and type 308L for the second layer. Roll bond cladding is not acceptable. The Bidder shall submit his procedure for applying the weld overlay for The KNOC's review.
After
the overlay material is applied, the tube sheet shall be stress relieved. Then the cladding shall be machined to a minimum thickness of 6.4 mm (1/4"). B. Welding, rolling procedures and joint configuration are subject to approval by KNOC. 6.7.5.3.6 Tube support plates and baffles A. Tube support plates shall be spaced to prevent vibration induced damage to tubes during all operating conditions.
6.7-22 KHABAT TPP UNITS 1&2 - VOLUME I
B. Support plate tube holes shall be deburred, with edges "broken"(or slightly chamfered) on both sides. C. Larger diameter tube bundles shall be provided with support plates, or their equivalent, at the U-bends. D. Impingement baffles of stainless steel shall be provided opposite all nozzle connections where impingement of steam or water might cause erosion of tubes. Baffles shall be designed to preclude transmission of vibration to the tubes and also to protect the tube bundle from rebound. Where necessary all impingement baffles shall be attached to the shell or appropriate parts with full penetration welds and liquid penetrant tested in accordance with Appendix VIII of ASME B & PV Code SEC. VIII. 6.7.5.3.7 Connections A. In addition to the normal connections provided for steam inlet, drains, vents, feedwater inlet and outlet, the heaters shall be provided with connections for level controls, level alarms and indicators, chemical cleaning,
pressure
and
temperature
instrumentation,
nitrogen
blanketing, HEI and ASME test taps as required. B. All connections shall be oriented radially and all connections for heaters except for the shell side safety relief valves acid cleaning nozzle shall be welded. Connections 65 mm(2-1/2") and larger shall be butt welded unless this specification states otherwise. Connections 50 mm(2") and smaller shall be socket welded. C. The shell side safety relief valve connections shall be flanged. The tube side safety relief valve connections shall be socket-welded type. D. The incoming drain connection to heaters shall enter the next heater shell on horizontal center line at the U-bend end, beyond the tube bundle. Stainless steel baffles shall be provided to protect the U-bend in the flash chamber. E. All connections shall extend beyond the insulation thickness. 6.7.5.3.8 Accessories F. The Bidder shall size a connection and provide a heavy duty thermal relief valve to protect the tube side of the feedwater heater. Valve size, type, and material shall comply with ASME and HEI Code requirements.
6.7-23 KHABAT TPP UNITS 1&2 - VOLUME I
G. The Bidder shall size a connection and provide safety relief valves to protect the shell against tube breakage in accordance with the HEI Standards, Paragraph 6.1.2. H. Safety relief valves shall be shop tested, set and tagged. The minimum tag information shall include identification number, set pressure and accumulation. 6.7.5.3.9 Materials All materials used in constructing the equipment to be furnished, but which are not specifically indicated in this specification, shall conform to HEI requirements, shall be the most suitable for the service intended and shall be subject to approval by KNOC. Material certifications of all materials tests for chemical analysis and mechanical properties of the tubes, tube sheet, channel, and shell shall be furnished to KNOC for review. A. Carbon steel plate : ASTM A-516 Grade 70, ASTM A-283 Grade C for pressure containing parts, ASTM A-36 for nonpressure containing parts. B. Carbon steel forgings : ASTM A-105 Grade II, ASTM A-266 Class 2 or ASTM A-350 Grade LF2, LF3 or equivalent. C. Tubes : ASTM A213 304N for heaters 5,6,7. D. Impingement plates : ASTM A-240 Type 304L. Internal impingement baffles in drains discharging into the shell shall be austenitic stainless steel. E. Nozzles : ASTM A-106 Grade B or A-335 Grade P11 for all heaters. F. Nozzle Liners : Fabricated stainless steel in accordance with ASTM A240 Type 304, with a maximum carbon content of 0.03 percent. G. Orifice plates : ASTM A240 Type 316L H. Gaskets : Carbon steel, metal jacket type for heaters 5,6,7. I.
The use of copper alloys in any part of the units is not acceptable.
J. The material of shroud and baffles for heaters 5,6,7 desuperheating zone shall be selected considering the high temperature and high pressure steam. 6.7.5.3.10 Manufacture Refer to LP heater's section(Same as that of LP heater)
6.7-24 KHABAT TPP UNITS 1&2 - VOLUME I
6.7.6
Instrumentation and controls A. The Bidder shall design and supply all instrumentation and controls so as to insure accurate, safe and reliable operation under conditions of service. B. The Bidder shall design the feed water system to be started, stopped, controlled and monitored by the PCS. C. Instrumentation and controls shall be designed in accordance with the section 8 of this technical specification. D. Dual redundant instruments shall be supplied for following applications as a minimum. 1) Feedwater storage tank temperature transmitter : 2 2) BFP suction temperature transmitter : 2/pump 3) BFP suction pressure transmitter : 2/pump 4) BFP suction flow transmitter : 2/pump 5) BFP discharge pressure transmitter : 2/pump 6) Economizer inlet feedwater pressure transmitter : 2 7) Economizer inlet feedwater flow transmitter : 2 8) Feedwater storage tank level transmitter : 2 9) Feedwater Heater Level Transmitter : 2/heater E. The Bidder shall provide designated instrument type for the following BOP process. 1) HP heater and FW storage tank level transmitter : differential pressure type 2) HP heater, FW storage tank level gauge : magnetic type
6.7-25 KHABAT TPP UNITS 1&2 - VOLUME I
6.8
Main and Reheat System
6.8.1
System Description
6.8.1.1 The main steam and reheat steam system transfers steam from the steam generator to the turbine-generator. 6.8.1.2 The main steam and reheat steam system consists of the main steam system, the cold reheat steam system and the hot reheat steam system, including each instrumentation and controls. A.
The main steam system starts from the superheater outlet nozzles of the steam generator through [1] main steam lines. The main steam lines, which are separated to [2] lines near the main steam stop valve, are connected to the main steam stop valve inlets.
B.
The cold reheat steam system starts from the [1] exhaust lines of the high pressure turbine and are connected to the 1st stage reheater inlet header of the steam generator.
C.
The hot reheat steam system starts from the [1] lines of the last stage reheater outlet and the hot reheat steam lines, which are separated to [2] lines near the reheat steam stop valve, are connected to the hot reheat steam stop valve inlets.
D. 6.8.2
Drain line with MOV, bypass line and steam trap.
System design criteria
6.8.2.1 General 6.8.2.1.1 Main and hot reheat steam lines and other lines with special schedule use the pipe bends with minimum radius of five (5) diameters. The pipe bends with radius of three (3) diameters shall be used for convenient pipe routing so long as they don't affect the system or equipment. 6.8.2.1.2 The main and hot reheat steam temperature at the steam generator discharge is 541/541 ℃. 6.8.2.1.3 The nozzle load of pipes connected to each equipment shall be designed within the allowance provided by the equipment Tender. 6.8.2.1.4 For the preparation of a long-term shutdown, the main and reheat steam system shall be designed so that inert gas blanketing or wet lay-up might be available.
6.8-1 KHABAT TPP UNITS 1&2 - VOLUME I
6.8.2.1.5 Drains and vents Proper drainage and venting of the steam lines is essential during startup to prevent accumulation of water in these lines. The design criteria for drain line and drain pot sizing and venting system of main and reheat steam system shall be described in the Design Criteria for Main and Reheat Steam System. A.
The main steam piping shall be designed with adequate drainage to prevent water entering the turbine.
Danger of water entering the turbine
from the main steam piping is greater during startup or shortly after shutdown of a unit because of steam condensation. B.
A drain shall be installed at each low point of main and reheat steam system
C.
All the drain lines and drain pot of main and reheat steam system shall be sized adequately according to applicable code.
D.
The power-operated drain valves open automatically on turbine trip and can also be remotely operated from the control room.
E.
The drains arrangement must satisfy the turbine water induction prevention requirements of ASME Standard No. TDP-1.
F.
The automatic venting system for start up shall be installed to warm up the main and reheat steam line in front of each turbine stop valve.
6.8.2.2 Main steam system 6.8.2.2.1 Main steam design pressure shall be matched with turbine and boiler design pressures so that steam generator safety valves may protect main steam piping in accordance with ASME Boiler and Pressure Vessel Code and ASME B31.1. 6.8.2.2.2 Component description A. Flow rate
: Flow rate calculated with the heat balance diagram at valve wide open
B. Design pressure
: Pressure calculated per ASME B31.1 Paragraph 122.1.2(A.4)
C. Design temperature
: Temperature range recommended by the
Steam
generator
and
turbine
generator D. Maximum flow velocity
: About 60 m/s against the noise and vibration (Design 50 m/s) 6.8-2 KHABAT TPP UNITS 1&2 - VOLUME I
E. Pressure drop
: Pressure drop designed for 95% of the pressure
differential
between
the
steam generator superheater outlet design pressure and the turbine main stop valve inlet design pressure F. Pipe material
: ASME SA-335, Gr. P91
6.8.2.3 Cold reheat system 6.8.2.3.1 Piping The cold reheat system shall be designed to transport the cold reheat (CR) steam from the high pressure turbine exhaust to the steam generator reheater. Connections shall be provided on the CR piping for blowing out all foreign materials after piping installation. A reheat hydro-test isolating provision(blind flange) may be provided in the CR piping for isolating the HP turbine exhaust during hydrostatic-testing of the reheat system. 6.8.2.3.2 Component description A. Flow rate
: Flow rate calculated with the heat balance diagram at valve wide open
B. Design pressure
: The higher of the two values of : 1.15 times
the
high
pressure
turbine
exhaust pressure based on valve wide open heat balance diagram and 1.15 times the pressure due to fail-open condition of the high pressure turbine bypass valve. Full vacuum condition also to be considered as a design parameter. C. Design temperature
: Temperature range recommended by steam generator and turbine vendors
D. Maximum flow velocity
: 75 m/s (Design 40 m/s) The system shall be designed such that it is not damaged due to transient forces caused by steam or saturated water. 6.8-3 KHABAT TPP UNITS 1&2 - VOLUME I
E. Pressure drop
: The system shall be designed for about 40% of the pressure drop between high pressure turbine exhaust and intermediate pressure turbine inlet. The pressure drop to be calculated based on heat balance diagram at valve wide open and with safety margin of 5%, excluding the pressure drops due to reheaters and the turbine exhaust check valves.
F. Pipe material
: ASTM SA-335, Gr. P11
6.8.2.4 Hot reheat system 6.8.2.4.1 Piping The hot reheat system piping shall be designed to convey hot reheat system steam from the steam-generator reheater outlet to the T-G Combined Reheat Valves(CRV) for all flows from startup to maximum load conditions through a double header system. The reheat valve assembly shall be supplied by the turbine manufacturer as a combination of a strainer and two valves in series, an intercept valve (IV) and a reheat stop valve(RSV). The IVs and RSVs provide a double line of protection. The reheat valve assemblies pass steam into the intermediate pressure turbine.
Reheater stop valves close on turbine trip and intercept
valves modulate after the trip to prevent turbine overspeed. 6.8.2.4.2 Component description A. Flow rate
: Flow rate calculated with the heat balance diagram at valve wide open
B. Design pressure
: Pressure not less than the lowest setting pressure of the reheater safety valve and to be considered full vacuum condition as a design parameter
C. Design temperature
: Temperature range recommended by the
Steam
generator
and
turbine
vendors D. Maximum flow velocity
: 100 m/s (Design 55 m/s) 6.8-4 KHABAT TPP UNITS 1&2 - VOLUME I
E. Pressure drop
: The system shall be designed for about 60% of the pressure drop between high pressure turbine exhaust and intermediate pressure turbine inlet. The pressure drop to be calculated based on heat balance diagram at valve wide open and with safety margin of 5%, excluding the pressure drops due to reheaters and turbine exhaust of check valves.
F. Pipe material
6.8.3
: ASME SA-335, Gr. P91
Instrumentation and controls A.
The Tender shall design and supply all instrumentation and controls so as to insure accurate, safe and reliable operation under conditions of service.
B.
The Tender shall design the main and reheat steam system to be controlled and monitored through the PCS.
C.
Instrumentation and controls shall be designed in accordance with the section 8 of this technical specification.
D.
Redundant instruments for system shall be supplied for following applications as a minimum. 1) Main steam line temperature transmitter : 2 2) Main steam line pressure transmitter : 2 3) Cold reheat line temperature transmitter : 2 4) Feedwater Heater Level Transmitter : 2/heater
6.8-5 KHABAT TPP UNITS 1&2 - VOLUME I
6.9
Feedwater Heater Extraction, Drain and Vent System
6.9.1
System description The function of this system is to provide partially expanded steam from the turbines to the feedwater heaters in order to heat the feedwater entering the boiler for the purpose of increasing the thermal efficiency. A. Extraction steam The function of heater extraction system provides expanded steam from a number of stages of the turbines to low pressure and high pressure feedwater heaters. B. Heater drains The function of the heater drain system is to drain the condensate from the feedwater heaters to the next lower heaters or condensers. C. Heater vents The function of the heater vents system is to vent the air and noncondensable gases from the heater shells and channel to the deaerator, condenser or release to atmosphere. D. Pressure relief system The function of the pressure relief system is to protect the feedwater heaters from the over pressurization. Feedwater heater extraction steam vents and drains system consists of : extraction steam system, heater drains system, heater vents system and pressure relief system. The system design scope includes above items along with the associated piping, valves, instrumentation and controls.
6.9.2
System design criteria The design capacity of feedwater heater extraction, drain & vent system is based on the steam flow at turbine valve wide open (VWO) load. Design of the extraction steam system should be in accordance with ANSI/ASME TDP-1, "Recommended Practices for the Prevention of Water Damage to Steam Turbines Used for Electric Power Generation" to protect turbine damage caused by water induction. Feedwater will be heated 7-step feedwater heater composed of 3-step low pressure feedwater heaters, deaerator and 3-step high pressure feedwater heaters. All feedwater heaters excluding deaerator are equiped with internal drain coolers. 6.9-1 KHABAT TPP UNITS 1&2 - VOLUME I
Serial numbering of feedwater heaters shall be from low pressure feedwater heaters to high pressure feedwater heaters. That is, the lowest feedwater heater is No.1 and the highest feedwater heater is No.7. Feedwater heaters from No.1 to No.7. have one feedwater heater with capacity of 100% each. Design pressure for shell side of feedwater heaters is the pressure at heat balance VWO plus 15% margin considering the pressure fluctuations like misstaging of turbine. Also full vacuum should be considered. Design temperature of closed feedwater heaters shall be determined by HEI standards. Design temperature of deaerator shall be the maximum temperature between pegging steam temperature and normally supplied steam temperature. TTD (Terminal Temperature Difference) and DC (Drain Cooler Approach) of feedwater heaters will be as follows based on heat balance at VWO condition. Items No.1 ~ No.3 Feedwater Heater No.4 Feedwater Heater (Deaerator) No.5 & No.7 Feedwater Heater No.6 Feedwater Heater 6.9.3
TTD
DC
1.67 ℃ (3℉)
5.6℃ (10℉)
0℃ (0℉)
-
-1.67 ℃ (-3℉)
5.6℃ (10℉)
0℃ (0℉)
5.6℃ (10℉)
Extraction steam system
6.9.3.1 Design parameters A. Flow rate : Valves wide open heat balance flows. B. Design pressure : Extraction pressure from VWO, heat balance times 1.15, but not less than 3.5 kg/cm2(g). Also considering full vacuum condition in design. C. Design temperature : Steam temperature corresponding to design pressure based on the VWO heat balance with 15% margin. D. Maximum steam velocity : 75 m/s E. Maximum Allowable pressure drop (from turbine stage outlet flange to heater inlet nozzle) of feedwater heater extraction steam piping shall not exceed 5% pressure of turbine extraction steam point F. Extraction steam line size 6.9-2 KHABAT TPP UNITS 1&2 - VOLUME I
a) Steam velocity of extraction steam line shall not exceed 75 m/s. b) Design pressure drop shall be based on 90% of available pressure drop. 6.9.3.2 Bleeder trip valve Bleeder trip valve shall be installed in the extraction steam lines of feedwater heaters (Except No.1 heaters). Bleeder trip valves shall be in accordance with the recommendation of turbine manufacturer. 6.9.3.3 Shut-off valve of extraction steam line Shut-off valves shall be installed in the extraction steam line of feedwater heaters (Except No.1 heaters). Shut-off valve shall be installed to protect water induction to turbine, for which motor operated shut-off valves shall be installed. 6.9.3.4 Drain piping and valves for extraction steam lines Drain piping connected to condenser shall be installed in extraction steam lines to drain the extraction steam lines. Drain valves shall be operated through main control room, and shall open automatically when the turbine is tripped and bleeder trip valves of extraction steam lines are closed. 6.9.3.5 Extraction steam piping Extraction steam piping will be routed and supported in such manner as to provide for thermal expansion and to maintain end reaction forces and moments within allowable limits. All low pressure extraction piping inside the turbine exhaust hood will be provided with sleeved stainless steel bellow expansion joints. Extraction steam piping installed inside the condenser shell shall be fixed at the condenser shell. 6.9.4
Drain system All the necessary drains from pipework, steam chests, turbine cylinders etc, shall be led separately by gravity to a flash vessel discharging to the condenser through a system of continuously falling drain pipes, valves and orifices. Drain vessels shall be designed in accordance with PD 5500 or equivalent internationally recognized standard. The design and operation of the drains system shall ensure that during start6.9-3 KHABAT TPP UNITS 1&2 - VOLUME I
up air is not introduced into the condenser. Drains that are normally at atmospheric pressure during start-up shall be vented to atmosphere via the atmospheric drains vessel. The drains vessel and valves shall be located for ease of access and maintenance. Each drain shall be provided with a remote temperature indication monitored upstream of each drain control position. The temperature indications shall be displayed on a suitable PCS format in the CCR. Drain cooling/desuperheating sprays shall be provided as appropriate in the drains flash vessel. 6.9.4.1 Design parameters A. Drains : The following two kind of drains shall be provided : primary drains to next lower pressure feedwater heaters and emergency drains to condenser hotwell. In low pressure feedwater heater drain system feedwater heater drain pump shall not be installed. B. Design pressure : Feedwater heater shell side design pressure (upstream of control valve) C. Design temperature : Based on VWO, heat balance D. Flow velocity : Within the 2.5 m/s (upstream of control valve) E. Control valve type : Two valves in series shall be provided for each operational drain, the upstream or isolating valve being of the parallel slide type and lockable in the open position. The downstream or regulating valve shall be preferably of the globe type. All drain valves shall be conveniently grouped together where practicable. Regulating drain valves shall be motorized to aid automatic plant operation. F. Control valve capacity 1) Primary drain valves : VWO heat balance flow at a nominal 80% valve travel. Valves to be suitable for control at minimum flow at which cascading to next lower pressure heaters is still possible. 2) Emergency drain valves : The emergency drain control valves (drains to condenser) shall be capable of handling, with valves in fully open position, the total drain flow with one (or more, as required) upstream heaters out of service. G. Control valve size : Valve body size shall not be less than nominal pipe size which is one step smaller than inlet pipe size. H. Location of control valves
6.9-4 KHABAT TPP UNITS 1&2 - VOLUME I
1) Primary drain valves shall be installed near the inlet nozzle of the next lower feedwater heaters in order to minimize the piping connections affected by flashing. 2) Piping affected by flashing in the direction changes more than 45† between primary drain valves and feedwater heaters shall have tee fittings having the blind flange on one side. 3) Emergency drain valves shall be installed near the inlet nozzle of condensers and inline to minimize the piping area affected by flashing. 4) Piping installed between emergency drain control valves and condensers shall not have any vents. I.
Block valves: Block valves shall be installed at the upstream and downstream of primary drain valves and emergency drain valves, but bypass valve shall not be installed. During the operation of feedwater heaters, one of the primary drain lines and emergency drain lines must be used for drain.
6.9.5
Vent system A. System design 1) Follow the recommendation of feedwater heater manufacturer 2) Noncondensable gas of high pressure feedwater heaters shall be drained to deaerator or condensers through the flow restriction orifices, and noncondensable gas of low pressure feedwater heaters shall be drained to condensers through the flow restriction orifices. 3) If the vacuum ratio of condenser is normal, noncondensable gas of deaerator shall be drained to condenser but in abnormal conditions the noncondensable gas shall be drained to atmosphere though the orifices in each case. 4) All heaters except deaerator and No.1 heaters shall be provided with vent lines which will be used during start-up operations only. B. Maximum flow velocity : Within the 40 m/sec C. Design pressure : Feedwater heater shell side design pressure D. Design temperature : Feedwater heater shell side design temperature E. Shell side vent size: The shell vent line will be sized for venting approximately 0.5 percent of the extraction steam entering the heater.
6.9-5 KHABAT TPP UNITS 1&2 - VOLUME I
6.9.6
Pressure relief system Feedwater heater relief valve capacity : Relief valve shall be designed in accordance with hydraulic institute standards and considering the condition of upstream drain valve trouble. Deaerator shell side relief valve :Relief valve shall be designed considering the problems caused by the following valves : valve for pegging steam, drain valves for No.7 Feedwater heater and drain valves for feedwater storage tank.
6.9.7
Instrumentation and controls
A. The Bidder shall design and supply all instrumentation and controls so as to insure accurate, safe and reliable operation under conditions of service. B. The Bidder shall design the main and reheat steam system to be controlled and monitored through the Plant PCS. C. Instrumentation and controls shall be designed in accordance with the section 8 of this technical specification unless otherwise specified in this section.
6.9-6 KHABAT TPP UNITS 1&2 - VOLUME I
6.10
Auxiliary Steam System
6.10.1
System description During normal operation, the auxiliary steam requirements of the plant will be supplied from an operating boiler. The auxiliary steam supply system shall be arranged to have sufficient redundancy and isolation points to enable maintenance of any valve or other component in the system to be carried out safely without requiring the shut-down of the Unit. The function of the auxiliary steam system is to provide a supply of low pressure superheated steam for various plant uses, as required, during plant operation. Auxiliary steam is supplied from the cold reheat system, the steam generator superheater outlet and auxiliary bolier. The primary source depends on the operating mode of the plant and the load carried on the unit.
6.10.2
System design criteria
6.10.2.1
General description A.
Auxiliary steam header consists of [9]bar.g of superheated steam.
B.
During shutdown of the one unit, auxiliary steam header should be supplied the steam from other unit connecting cross tie between other units.
6.10.2.2
Facilities to be provided auxiliary steam A.
Auxiliary steam header supplies to the following services : 1) Turbine gland steam seal system 2) Deaerator pegging 3) Boiler, EP, Ash handling system 4) Atomizing steam 5) Fuel tank heating 6) Water treatment system 7) Aux. steam header by other unit 8) Miscellaneous outside building steam supply 9) All other equipment as identified in auxiliary steam
6.10-1 KHABAT TPP UNITS 1&2 - VOLUME I
B.
Maximum flow velocity 1) Superheated steam piping - 25 ~ 200 mm - More than 200 mm
: 45 ~ 76 m/s : 76 m/s
2) Saturated and wet steam piping (More than 1.75 bar.g) - 25 ~ 200 mm - More than 200 mm
: 30 ~ 48 m/s : 40 m/s
3) Saturated and wet steam piping (Less than 1.75 bar.g) - 25 ~ 200 mm - More than 200 mm 6.10.2.3
: 18 ~ 31 m/s : 31 m/s
Pressure control valve shall be provided to control pressure of steam supply from superheater outlet or cold reheat line.
6.10.2.4
Flow control valve and shut-off valve shall be provided to control flow of process steam supply to other site and to protect disturbance flow from other site abnormal condition.
6.10.2.5
Check valves shall be provided in the superheater aux. steam outlet header and in the cold reheat system aux. steam supply line in order to prevent aux. steam from entering the main boiler when it is shutdown.
6.10.2.6
Desuperheaters shall be provided in the line from main header to process steam line and required lines in order to reduce the aux. steam temperature to be compatible with the design condition of user equipment.
6.10.2.7
Steam flow measuring system shall be provided in the lines between the power plant units and none power plant systems to be monitored by PCS the steam consumption at each usage ends
6.10.2.8
System Operation Requirements A.
Start-up and shutdown The auxiliary steam supplied to the unit during plant shutdown shall come from the aux. steam header of the normal operating unit, or auxiliary boiler.
B.
Normal operation During normal power operation, the auxiliary steam source will changes as plant load changes. This operation will be able to be performed automatically or by operator action from the main control room.
6.10-2 KHABAT TPP UNITS 1&2 - VOLUME I
C.
Capacity : Operating requirements of "user" system plus 10% spare capacity for possible future use.
D.
Design pressure and temperature 1) Design pressure
: [20] kg/cm2.g
2) Design temperature
: Correspond to design pressure and
enthalpy supplied steam Instrumentation and controls
6.10.3 A.
The Bidder shall design and supply all instrumentation and controls so as to insure accurate, safe and reliable operation under conditions of service.
B.
The Bidder shall design the auxiliary steam system to be started, stopped, controlled and monitored through the Plant PCS.
C.
Instrumentation and controls shall be designed in accordance with the section 8 of this technical specification unless otherwise specified in this section.
D.
Two or triple redundant instruments for BOP shall be supplied for following applications as a minimum. 1) Aux. steam header pressure transmitter : 2 2) Aux. steam header temperature : 2
6.10-3 KHABAT TPP UNITS 1&2 - VOLUME I
6.11
Closed Cooling Water System
6.11.1
Extent of work A closed circuit cooling water (CCW) system shall be provided as part of the Works, to supply treated demineralized cooling water to the coolers associated with the plant.
The closed circuit cooling system shall be cooled
by the primary cooling water system, the closed circuit system receiving and discharging cooling water to the supply and return side of the main condenser. The scope of work for the closed circuit cooling water system comprises the complete system design and all related piping and equipment within the limits defined herein. It is not the intent to specify all details of design and construction, however, the main system components described below shall be provided, including, but not limited to: A. Two (2) 100% CCW heat exchangers for two(2) units B. Two (2) 100% CCW pumps for two(2) units C. One (1) CCW header tank with its related pipe work, valves and fill water connection for two(2) units D. Chemical pot feeders complete with inlet and outlet isolation valves, drain valve, vent valve and charging valve. The scope of supply includes all secondary coolers and related piping, valves and
operators,
hangers
and
supports
including
secondary
steel,
instrumentation and controls, miscellaneous equipment and piping specialities for the system. 6.11.2
General requirements The design, manufacture, installation and test of the materials, equipment and work shall be in accordance with all applicable HEI Codes and with the requirements of the Specification. All materials used in the system shall be suitable for use with river water and/or inhibited demineralized water as applicable throughout the full generating temperature range of the system. The demineralized water shall be dosed with a suitable corrosion inhibitor. 6.11-1 KHABAT TPP UNITS 1&2 - VOLUME I
The system shall include all instrument, vent and drain valves and pipework to suitable disposal points as approved by the KNOC. 6.11.3
System description The CCW system shall provide the cooling requirements for the auxiliary plant and equipment. The system shall be designed to ensure satisfactory distribution of water at the required temperature to all CCW users, and the coolers shall have sufficient capacity to dissipate the total heat generated with the plant operating at peak load at the maximum operating temperature. The CCW system design shall be capable for providing cooling requirements for all plant. The closed circuit cooling water system shall be arranged such that during normal operation, the cooling water cycle shall be supplied by one (1) operating (100%) cooling water pump circulating treated demineralized water through one (1) operating (100%) heat exchanger to all equipment consumers requiring a cooling medium for their operation. Either cooling water circulating pump should be able to operate with either heat exchanger. The header tank shall be located above the highest elevation of the closed circuit cooling water system, and shall be connected to the pump suction return pipelines. A make-up line shall be supplied to the header tank from the demineralized water supply system. The Tender shall provide valved connections on the CCW system for the introduction of a corrosion inhibitor into the system and for the downstream sampling of the cooling water. ‘Oil in water’ monitors shall be provided in the closed circuit cooling water returns and alarmed to the PCS.
6.11.4
System operation The first (duty) cooling water pump shall be started either automatically or manually via the PCS after the main cooling water flow has been established through one (1) of the cooling water heat exchangers.
The second
(standby) pump shall be started automatically on low flow in the cooling water supply header or on trip of the duty cooling water pump motor. An alarm shall 6.11-2 KHABAT TPP UNITS 1&2 - VOLUME I
be provided to announce automatic starting of the second (standby) pump. The auxiliary coolers shall be supplied with a manual flow control valve (with locking device) which shall be set during system commissioning and adjusted, as required thereafter, to give the required cooling water flow from the constant pressure source in the supply feed. These valves shall not be used as isolation valves. 6.11.5
CCW pumps Two (2) 100% capacity circulating water pumps shall be provided for the CCW system. The pumps shall be of the centrifugal, horizontally mounted, single stage, split casing type designed to give the specified output against all losses, including those relating to the pump. The delivery head of each pump shall be designed to meet the requirements of the closed circuit cooling water system, including a 10% margin on flow and a 5% margin on head. The pumps shall be identical and capable of parallel operation without throttling and as a single unit without cavitation or overload under all operating conditions with the pump characteristics matched to the relevant pipe system network to achieve the highest pump efficiency and reliability. The pumps and piping systems shall be capable of withstanding the transient pressure associated with a rapid closure of the discharge valves of a running pump or of a pump shut down. The Tender shall take all precautions in designing the system to limit system water hammer. The pumps shall have a non-overloading characteristic over the complete range of head and quantity delivered and the drive shall be capable of starting the pumps against a closed valve (ie maximum pump head conditions). The whole pumping unit shall be capable of withstanding, without detriment, reverse rotation to a speed that would occur if the pump were to stop when the differential head was at a maximum and the delivery and/or non-return valve failed to close. The pumps shall be standard units of a reputable manufacturer and shall conform to the requirements of standards as prescribed in the Specifications. Pump performance curves shall be submitted. 6.11-3 KHABAT TPP UNITS 1&2 - VOLUME I
6.11.6
Cooling water heat exchangers Two (2) 100% capacity cooling water heat exchangers shall be provided. Each heat exchanger shall be of the plate type using main circulating water as the cooling medium. The cooling water side shall be designed with low pressure loss so that design flow is achieved with the pressure differential between the supply and return circulating water at its lowest. The CCW heat exchangers shall be designed for satisfactory plant operation over the full range of cooling water temperatures and with a cleanliness factor whose arithmetic mean value is not greater than 0.9 or with a 10% margin on the surface area. Each heat exchanger shall be sized to cool the entire flow from one (1) CCW pump at the calculated temperature differential of the closed circuit before adding the flow margin. The frame of each heat exchanger shall be designed to permit the future installation of a minimum of 20% additional plates. Fouling factors will be as recommended by TEMA. Each heat exchanger shall be designed with the plate pack mounted between a stationary frame plate and a movable pressure plate. The plates shall be compressed by the tightening of longitudinal bolts connecting the moveable pressure plate to the stationary frame plate. The design of the unit shall be such as to enable the plates to be removed for cleaning and inspection without the need to disconnect the supply and return piping. The heat exchangers shall be complete with vents, drains, and all necessary connections, studs and bolts, venting shall be completed without the intermixing of the cooling media. The plates shall be designed for the shut-off head of the cooling water pump plus the header tank static head, rounded up to the nearest 1.0 bar gauge. The plates shall be manufactured from titanium with gaskets of nitrile rubber or other material designed for a life time of not less than 10 years. Two (2) strainers shall be provided, one at the river water inlet to each heat exchanger, in order to protect the heat exchanger from blockage/fouling due to particles within the river water. Each strainer shall include differential pressure indication and alarm, with automatic back flushing (self-cleaning) facility designed to allow uninterrupted 6.11-4 KHABAT TPP UNITS 1&2 - VOLUME I
flow to the heat exchanger. Backwash flow from the strainer shall be returned to the condenser CW outlet pipework. 6.11.7
Cooling water header tank One (1) CCW header tank shall be provided, to ensure a constant inlet head to the circulating water pumps. The tank shall include a make-up water connection from the demi-water supply system, complete with automatic water level control valve and integrating flow meter. The tank shall be equipped with a level indicator and with high and low level alarms. The make-up connection shall be equipped with a flow alarm announcing high make-up flow. The cooling water header tank shall be large enough to compensate for level variations during the start-up (heat up) and shut-off (cool down) of the CCW system and designed to provide for system leakage for a 24 hour duration when the system is at operating temperature. The header tank shall be manufactured from mild steel with a minimum corrosion allowance of 1.5 mm. An overflow shall be furnished, piped via a tundish to the nearest floor or equipment drain, with inspection facility for monitoring flow. The head tank shall operate at atmospheric pressure and shall be located at the highest point in the system.
6.11.8
Chemical dosing The system for corrosion prevention in the CCW system shall be based on the use of an oxygen scavenger and a pH buffer. The operational pH shall be between pH 9.3 and pH 9.5. Other chemical dosing regimes can be offered subject to the approval of the KNOC. Injection of the dosing solution shall be by a bypass pot feeder. Chemical pot feeders shall be of an appropriate size. They shall be complete with inlet and outlet isolation valves, drain valve, vent valve and charging valve. Charging shall be manually through a purpose designed charging funnel. Means of ensuring that the intended volume of dosing solution can be measured shall be included. The position of the pot feeder shall be such that 6.11-5 KHABAT TPP UNITS 1&2 - VOLUME I
the valves are readily accessible. The point of entry into the CCW system shall be such that adequate dilution and mixing of the charge takes place when the valves are operated. 6.11.9
Instrumentation and controls A. The Bidder shall design and supply all instrumentation and controls so as to insure accurate, safe and reliable operation under conditions of service. B. The Bidder shall design the closed cooling water system to be started, stopped, controlled and monitored through the PCS. C. Instrumentation and controls shall be designed in accordance with the section 8 of this technical specification unless otherwise specified in this section. D. Two or triple redundant instruments for system shall be supplied for following applications as a minimum. •
CCWP discharge pressure transmitter : 2
•
CCW tank level transmitter : 2
6.11-6 KHABAT TPP UNITS 1&2 - VOLUME I
6.12
Circulating Water System
6.12.1
General Prior to design the Bidder shall undertake a comprehensive survey and analysis of the intake water source to ensure that all necessary design parameters are accurately defined. The Bidder shall, taking into account all relevant environmental restrictions, establish the optimum location for the intake and outfall, and shall construct appropriate intake and outfall structures complete with all necessary, pumping, filtration and maintenance facilities. The selection of pumps, pipework and valve equipment shall take into account the possible presence of high suspended solid burden in the water. These items shall be specifically designed to withstand erosion arising from the presence of suspended solids over the lifetime of the project. All suspended solids that might otherwise damage or impair the operation of the remainder of the cooling system shall be removed from the make-up water. The cooling water shall be chemically dosed to mitigate biological growth. The Bidder shall undertake sufficient sampling to ensure all system materials shall be suitable for use with the source of make up water. Copper alloys shall not be used in the manufacture of components in contact with cooling water.
6.12.2
System description
6.12.2.1 The primary function of the circulating water system is to provide cooling water to the main condensers for the purpose of condensing the turbine exhaust and L.P bypass steam for reuse in the turbine cycle. In addition, the circulating water system provides cooling water to the closed cooling water heat exchangers for removing heat from various plant components. It also provides cooling to the condenser vacuum pump seal water coolers. 6.12.2.2 The circulating system shall be designed on the basis of recirculated system with cooling towers. An evaporative-type, mechanical-draft cooling tower shall be provided to dissipate the heat to the atmosphere. Bidder is required to show by suitable analysis that his proposed design of circulating system shall meet the circulating requirements of the power station and environmental requirements at all times. 6.12.3
System design criteria
6.12.3.1 The Bidder shall optimize the circulating water system establishing the circulating water flow rate and temperature range. The optimization shall be 6.12-1 KHABAT TPP UNITS 1&2 - VOLUME I
carried out in association with the condenser and steam turbine's design condition. Bidder shall fully demonstrate an economic optimization of the circulating water system and its performance, and its effects on condenser and steam turbine performance and their optimization. 6.12.3.2 The circulating water system shall be designed to ensure that failure of any single plant component does not result in the shutdown of a steam turbine. 6.12.3.3 Common line should be installed between CWP discharge lines so that circulating water can be supplied to all condenser shells during some CWP trip. 6.12.3.4 System design and pump control system should be designed so as to protect against the peak transient resulting from unit start, stop and trip. 6.12.3.5 Piping design pressure A.
Minimum : Full vacuum
B.
Maximum : Peak transient analysis pressure or 1.5 times of circulating water pump shutoff pressure, which is greater
6.12.3.6 The circulating water pump shall be used to circulate water through the main condenser, which services a turbine-generator unit, for the transfer of waste heat to the heat sink. 6.12.3.7 Condenser tube cleaning system should be operated to maintain cleanness of the condenser tubes. 6.12.3.8 The Bidder shall provide the following information. A.
Details of the system resistance (head & flow) for all possible flow and operational configurations and variation in pump suction levels.
B.
System water velocities.
C.
System pressure rating.
D.
Detailed hydraulic steady state and transient analyses of the circulating water system shall be carried out during the detail design stage.
6.12.3.9 Component description A.
Circulating water pumps 1) Quantity : Two (2)×50% capacity + 10% margin capacity / unit 2) Type : Vertical mixed flow type or horizontal double suction type
6.12-2 KHABAT TPP UNITS 1&2 - VOLUME I
3) Design
capacity
:
Sum
of
the
flow
requirements
of
the
condenser(VWO condition) and all equipment requiring circulating water. 4) Design Head : The system head based on the highest point on energy gradient including cooling tower. B.
Cooling tower 1) Quantity : One (1)×100% capacity / 2unit 2) Type : Evaporative, Multi-cell mechanical-draft
C.
Condenser tube cleaning system 1) Quantity : Two (2)×50% capacity / unit
D.
Circulating cooling water pumps 1) Quantity : Two (2)×50% capacity + 10% margin capacity
6.12.4
Circulating water pumps
6.12.4.1 Design of condition A.
The pump shall be designed in accordance with the recommendation of the design standard of the Hydraulic Institute Standards. Pumps are required to discharge condenser design cooling water flow when the water level is at the lowest level and the cooling tower basin screens are in maximum allowable foul condition.
B.
For system designs which include pumps in parallel operation each pump shall be capable of continuous operation at maximum run-out condition
C.
The pump head-capacity curve shall be continuously rising from the maximum flow to shutoff.
D.
Pump design pressure shall not be less than the shutoff head.
E.
The first critical speed of the pump shall exceed the operating speed of the pump by at least 25 percent. Critical speed shall include effects of lubrication, bearings and bearing supports.
F.
The pump and motors shall be capable of withstanding without failure such design conditions including reverse rotation due to power failure.
G. The Bidder shall perform the vibration analysis of pump station and shall have responsibility to modify any harmful effect from vibration. The vibration analysis for each pump shall include the analysis for the operating conditions of starting, stopping and trip. H.
Circulating water pumps operation 6.12-3 KHABAT TPP UNITS 1&2 - VOLUME I
1) The pump shall be capable of operating over the complete range with efficiencies as high as possible, and be free of harmful effects from vibration, cavitation, or recirculation. The startup mode shown in curves is of short duration. 2) During startup and/or cold winter season, One(1) circulating water pump shall be taken out of service when not needed. In this case, one(1) circulating water pump shall discharge through a common line to one(1) condenser shell for each condenser shells. 3) The circulating water pump discharge shall be manifolded on the downstream side of the pump, and thus shall be subject to parallel operation. Each pump shall be capable of withstanding the reverse rotational speed caused by the head of the operating pump(s) at its discharge flange if the motor of the pump is deenergized. 4) The pumps and drive motors shall be suitable for continuous operation at any flow from shut off point to maximum runout flow. The Bidder shall state any limitations on the runout flow and shall also state the minimum continuous flow allowable. 5) The Bidder shall be provided the automatic air release valves in the pump's internal surface for the protection of circulating water system whenever the pump discharge conduit is under positive pressure. 6) The system shall include valves at the discharge of each pump and at the inlet and outlet waterbox of each condenser shell. 7) The circulating water pumps shall be started under two modes of system operation. One method of starting shall be when the circulating water system is empty and the adjacent circulating water pumps are not operating. The pumps shall also be started when the circulating water system is full of water and the adjacent circulating water pumps are operating. The circulating water pump starting sequence shall be designed to start the pumps under both modes of operation. a) The method of starting the pumps(with the system either empty or full) shall be as follows : The pump starting sequence shall take into consideration the inertia of the water mass in the circulating water system. The method of starting the pumps shall be designed to minimize the motor torque requirement and to optimize the
6.12-4 KHABAT TPP UNITS 1&2 - VOLUME I
motor efficiency at the pump rated conditions by timing the discharge valve opening with the pump/motor acceleration. b) The method of pump starting shall also be designed to prevent pump or motor damage in the event the discharge valve inadvertently fully opens during startup due to failure of the discharge valve control sequence. The Bidder shall state any limitations on the starting of the pumps in the event of a possible failure of the discharge valve control sequence. c) The starting sequence shall also be designed to prevent damage to the pump and motor during shutdown of the circulating water pumps. The shutdown of the circulating water pumps can occur when the circulating water system is empty and adjacent circulating water pumps are not operating or when the system is full and adjacent circulating water pumps are operating. The Bidder shall describe the required pump discharge valve closing sequence, and the effects if the control sequence fails and the valve becomes inoperative. 6.12.4.2 Design and construction features A.
General 1) The pump shall be designed for disassembly and assembly as they are being withdrawn or replaced in the cooling tower structure. 2) All assembly joints or junctions shall include alignment or centering fits as required to ensure accurate reassembly or alignment of all parts. 3) The pump construction in contact with riverwater shall be designed to avoid crevice corrosion. 4) The assembly such as joints, flanges, bolts and nuts shall be treated with anti-crevice corrosion sealant.
B.
Instrumentation and Controls 1) Field Instrument Requirements a) All dial type pressure indicators and temperature indicators shall be of liquid filled type to protect from vibration of pumps b) Instrument shall be supplied by one(1) recognized manufacturer having wide experience in the manufacture, application as possible. 2) Vibration Monitoring Devices 6.12-5 KHABAT TPP UNITS 1&2 - VOLUME I
a) The Bidder shall provide the vibration monitoring devices consisting of probes with protective housings, extension cables and transducers with housing for accurate and reliable vibration monitoring of pumps. b) The radial vibration probes shall be provided with two probes per bearing positioned radially at 90 degrees (X,Y). The dual axial vibration/position probes and keyphaser shall be provided for each pump. C.
Valve and pipework 1) The circulating water pump discharge valves should be capable of modulation in order to limit surge effects during opening and closing and attention shall be paid to the flow and modulation characteristics. The valves and their actuating equipment shall be capable conditions of CW pressure and flow, including operation against CW pump shutvalve pressure. 2) The CW pump discharge valves shall be arranged to open on remote manual control from the main control room. Consideration shall be given in the design to the rate of valve opening during filing of the discharge line and culverts. Main CW pump inlet valves shall be provided with motor actuators. The rates of closure for the valves shall be determined by the surge study and shall be selected to minimize hydraulic surge and prevent possible damage to the pump resulting from reverse rotation.
6.12.5
Cooling tower system
6.12.5.1 General A.
The cooling tower shall be designed as wet cooling tower.
B.
The cooling water shall be conveyed on both sides of the cooling tower through an appropriately designed inlet pipe to the heat exchanger bundles, where part of the heat is transferred to the cooling air flowing across. The water leaving the bundles flows into the water distribution by pipes and spray assemblies over the cooling fill.
C.
Cooling tower system shall be automatically operated.
D.
Materials containing asbestos shall not be used.
E.
Operation and maintenance of the tower should be as convenient as possible. Particular attention shall be also paid to the arrangement of the 6.12-6 KHABAT TPP UNITS 1&2 - VOLUME I
mechanical equipment(e.g. valves and motors) as well as platforms and workways, etc. F.
For operation in cold-weather, anti-ice formation measures shall be provided to protect the cooling tower and cold water basin from threatening performance and damage so that allow the cooling tower to be safely operated.
G. Anti-fouling type of fill media shall be used in the cooling tower and to minimize windage losses spray eliminators shall be fitted to the cooling tower air outlets. Specific attention shall be paid to the elimination of drift. 6.12.5.2 Structure A.
The cooling tower shall be induced draft type, with multi-cell arranged in one row. It consists of exterior walls, partition walls, fan deck, fan stack, internal and external supporting structures and the water basin.
B.
The fan stack shall be of a divergent type for velocity pressure recovery and shall have a rounded inlet shape to avoid air turbulences.
6.12.5.3 Cooling fill of wet section The heat exchange surface in the wet section shall be of the film flow type. Water shall be distributed above the fill covering the surfaces with a thin film of water.
Heat is transferred to the passing air by evaporation of water from the
film surface.
The cooling fill material shall be capable to withstand water
temperatures up to 60℃ without damage or permanent distortion.
The
cooling fill shall be the best heat transfer possible and minimize the air side pressure loss. 6.12.5.4 Water distribution The hot water shall flow in riser pipes at each side of the cells to the headers of the wet section arranged horizontally along the cell. To these headers distribution pipes shall be connected, which are arranged inside of each cell above the cooling fill. Each distribution pipe shall be equipped with an easily removable sealing cap for cleaning purposes. 6.12.5.5 Spray system At certain distances the water distribution pipes shall be equipped with screwed flanges acting as supports for the sprayers. The sprayers in their spraying arrangement shall ensure a uniform distribution of the water to be cooled. 6.12-7 KHABAT TPP UNITS 1&2 - VOLUME I
6.12-8 KHABAT TPP UNITS 1&2 - VOLUME I
6.12.5.6 Drift eliminator In order to reduce drift losses by entrained water droplets to the maximum possible a drift eliminator shall be arranged above the spray area. 6.12.5.7 Mechanical equipment A.
Axial-flow fans The impellers shall consist of the hub and blades connected to each other by means of clamping bearings. The surface of the steel hubs shall be protected by paint coats depending on their application.
B.
Fan driving motors The electric motors shall be surface cooled three-phase squirrel cage motors and appropriate for the drive of fans. A motor protection and an out-of-service heating shall be installed for application at very low ambient air temperature.
C.
Gearbox (bevel spur gear) The casing shall be of oil and dustproof design.
The shafts shall be
supported by largely dimensioned oil-lubricated anti-friction bearings. The design of the gear surfaces shall allow rejection of the heat produced not requiring the installation of oil cooler. Oil level indicator, drain and filler sockets shall be mounted at the exterior of the fan stack. D.
Drive shaft Power transmission from motor to gearbox shall be effected by means of a torsionally stiff flexible coupling : very long shafts shall be equipped with an intermediate bearing.
If necessary, connection between electric
motor and/or gearbox shall be made by means of flexible couplings. E.
Each cell has its own fan deck which is equipped with vibration monitoring equipment as well as oil-level gauge, temperature sensors, etc.
F.
The fan and other equipment shall be operated smoothly and without vibration.
6.12.5.8 Access to the tower and supporting structures All elevations shall be accessible via stairways and walkways to facilitate inspections and maintenance work.
6.12-9 KHABAT TPP UNITS 1&2 - VOLUME I
6.12.5.9 Piping system The necessary cooling system piping of the tower shall be designed and routed as to ensure a safe operation. Thermal expansion due to varying temperatures shall be compensated for by appropriate expansion joints. 6.12.5.10 Valves A.
The manual valves to isolate individual cells of the cooling tower shall designed as butterfly valves.
Casing and sealing disk and endless
sectional sealing ring shall be provided fastened to the valve disk by means of a retaining ring. The valve shaft shall be made from stainless steel complete with an o-ring sealing of shaft passage. B.
An electric actuator drives the valve through a self-locking gear. The limit switches for open and closed position shall be connected to plant control system(PCS).
6.12.5.11 Cooling tower cold water basin The Bidder shall design the cold water basin and submit the engineering and construction drawing for installation. The size of the storage (between normal and minimum level) must be sufficient for an operation of the system with nominal quantity for 30minutes without make-up water supply. Furthermore, the surge of water level in case of shut-down of all circulating water pumps has to be considered also for the design of the storage (maximum level). The normal level shall be controlled by the make-up water flow into the storage. 6.12.5.12 Chemical injection system A.
A non-chromate corrosion inhibitor, a microbiological growth control and an antiscalant chemical program shall be utilized to avoid corrosion, fouling and scale accumulation in the circulating water system. The chemicals used shall not require post treatment of the circulating water blowdown, and the blowdown shall comply with the applicable effluent water quality standards. The following chemicals shall be used.
B.
Corrosion Inhibitor Non-chromate corrosion inhibitor shall be injected into the circulating water system to control and minimize corrosion of the piping and heat exchangers. The liquid inhibitor shall be fed continuously, by a positive 6.12-10 KHABAT TPP UNITS 1&2 - VOLUME I
displacement metering pump, into the cooling tower basin. Proper inhibitor residual shall be monitored and maintained based on selected vendor's recommendation. C.
Sodiumhypochloride The control of microbiological fouling in the circulating water system shall be
accomplished
by
the
addition
of
sodiumhypochloride.
The
sodiumhypochloride shall be fed continuously, by a positive displacement metering pump, into the cooling tower basin. Dosage shall be maintained based on selected vendor's recommendation. 6.12.5.13 Cooling tower blowdown A.
The Bidder shall propose concentration ratio and blowdown rate for the cooling tower to meet the local regulation and/or World Bank environmental guidelines in his tender. The cooling tower blowdown shall be discharged to the river via a discharge basin, buried pipe and outfall also to be provided under this Contract. Two × 100% capacity blowdown pumps complete with isolation and non-return valves shall be supplied. The discharge shall have a residual chlorine level that is within the authorized environmental limits. A system shall be included to control the free chlorine content to this level if required.
B.
The temperature of the blowdown from the cooling circuit shall be compliant with World bank Environmental guidelines for pollution prevention and abatement in new plants. Redundant online temperature and pH monitoring of the discharge shall be provided and the information transmitted to the PCS. Flow measurement equipment to record the total volumes of water discharged to the river shall be provided.
6.12.5.14 Control and instrumentation A.
The complete instrumentation and control system shall be provided to control and monitor the cooling tower system.
B.
The cooling tower system control shall be implemented in the PCS.
C.
The normal operation of the system shall be operated from central control room.
D.
Instrumentation and controls shall be designed in accordance with the section 8 of this technical specification unless otherwise specified in this section.
6.12-11 KHABAT TPP UNITS 1&2 - VOLUME I
6.12.6
Condenser tube cleaning system
6.12.6.1 Description of condition A.
The condenser tube cleaning systems maintain condenser efficiency at design levels by removing bio-fouling, sediment, corrosion products and scaling. The condenser tube cleaning systems shall be located inside the turbine building.
B.
The riverwater may contain sand and debris of a size that shall pass through the 9.5mm(3/8inch) mesh travelling screens.
C.
The design data of condenser shall be incorporated in the condenser tube cleaning system design and the circulating water design/low flow condition.
6.12.6.2 Design features A.
Two(2) condenser tube cleaning systems shall be provided for each unit, and shall be required to operate at circulating water flow for plant load and seasonal variations.
B.
The system shall be designed to operate and function automatically to produce a clean interior surface in each tube.
C.
Rotating parts shall be provided with guards in accordance with OSHA standards.
D.
Components shall be designed to permit frequent repetitive cycling and required flow of the system without harmful effect.
E.
Condenser Tube Cleaning Systems 1) The strainer design pressure shall be determined by circulating water system transient analysis. 2) The strainer section including screen angle and screen bar spacing shall be selected, condenser tube cleaning system performance are satisfied for proper function during each flow conditions. The screen angle shall be optimized to assure proper sponge ball movement against the resulting screen pressure drop and screen bar spacing shall be optimized to prevent sponge ball penetration while minimizing pressure drop at the highest expected 'design' circulating water velocity. 3) The ball strainer section shall as a minimum contain the following components. The number of components shall be determined by the size of the strainer section. 6.12-12 KHABAT TPP UNITS 1&2 - VOLUME I
a) Screens to direct balls to the extraction tube. b) Drive mechanisms with motor operators for screens. c) Ball type, size and hardness for ball recirculation ability. 4) Motor actuators shall be of sufficient rating to rotate the screens against the circulating water flow for backwash purposes, i.e., to wash off the debris retained on the screens. 5) The balls shall be non-unicellular elastomeric and, when wetted, shall be of specific gravity nearly equal to but slightly greater than that of the circulating water for homogeneous distribution through the water passages. 6) The Bidder shall select the total quantity of balls so that each condenser tube shall receive a ball on an average of every 5 minutes and the ball shall have an excellent recovery rate more than 95% and effective tube cleaning to meet condenser performance. To be considered, the Bidder shall submit technical data. 7) The Bidder shall be considered such as inlet waterbox design with regard to uniform distribution of balls to all tubes. The ball shall be of the correct size to insure cleaning of the condenser tubes without excessive tube wear. 8) The Bidder shall provide the ball monitoring devices to automatically indicate required ball charge and recirculating ball quantity. 9) The Bidder shall provide the ball sorting devices to automatically sort the worn balls to be replaced by new ones. 10) The Bidder shall recommend if any abrasive balls should be included in initial charge or first year's supply and shall specify the quantity. 11) The ball recirculating pump shall be the non-clogging centrifugal type with wide clearance between impeller and housing to prevent damage to the balls. 12) The ball recirculating pump shall have sufficient capacity and head to ensure proper recirculation of the complete ball charge under all modes of operation. Pump speed shall be selected by the Bidder to minimize ball damage. 13) Each electric motor driver shall be rated so that the motor is not overloaded over the entire pump performance range.
6.12-13 KHABAT TPP UNITS 1&2 - VOLUME I
14) The ball collector shall be provided with motor actuated ball catching flap or valve. 15) Distributors shall be provided to equalize ball flow through individual lines. 16) A sight glass shall be provided to observe ball flow through the distributor. 17) The ball shall be guaranteed a lifetime long enough to maintain the appropriate tube cleaning performance. The abrasive ball shall be determined to be most suitable to remove any kind of deposits without damaging the tube surface. F.
Materials 1) All materials used in constructing the equipment shall be the best suitable for the service intended.
6.12-14 KHABAT TPP UNITS 1&2 - VOLUME I
6.13
Compressed Air Systems
6.13.1
General A compressed air system shall be provided to accommodate the requirements of both instrument and service air as appropriate for the complete power station. The compressed air system shall be capable of meeting all plant requirements during any operating condition, including start up, shutdown and trip. The standby compressor shall start up automatically in case of air pressure abnormally decreasing. Moreover, a valve in the service air supply main header shall shut automatically in case of very low air pressure to ensure continuity of instrument air supply which has priority over service air supplies. The air quality for the control air systems shall be filtered to 5 microns, with a dewpoint of -40°C. The air pressure in the pipe distribution system shall be [7 barg]. The filter/dryers supplied as part of the instrument air system shall be sufficient to condition the air required by the plant whilst the second train of filter/dryers is in standby mode. Air storage volume, compressor running periods and compressor control method are closely interdependent. The system designs shall be optimized for minimum total costs. The optimization calculations shall be submitted to the KNOC for approval. System design and equipment shall conform to the requirements and recommendations of the appropriate Codes and Standards.
6.13.1.1 Instument air system Instrument air system is provided compressed air from air compressors and supplies instrument air to the instruments. Instrument air system is composed of two (2) 100% capacity instrument air receivers, two (2) 100% instrument air filters, two (2) 100% instrument air dryers and instrument air distribution system, including instruments, valves, piping and supports. 6.13.1.2 Service air system Service air system supplies compressed air to instrument air system and consuming utilities. Service air system is composed of two (2) 100% capacity air compressors, 6.13-1 KHABAT TPP UNITS 1&2 - VOLUME I
one (1) service air receiver and service air distribution system, including instruments, valves, air-line couplings, piping and supports. 6.13.2
Scope of work Main equipment shall include, but not be limited to the following: A.
Two (2) 100% capacity air compressors, designed to operate on a duty/standby basis, each complete with suction air sand separator and filter/silencer, intercooler and aftercooler with moisture separators;
B.
one (1) general service air receiver of sufficient capacity to facilitate safe shut- down in the case of emergency, with all other provisions considered;
C.
two (2) 100% capacity instrument air receivers of sufficient capacity to facilitate safe shut-down in the case of emergency, with all other provisions considered;
D.
two (2) 100% instrument air filters;
E.
two (2) 100% instrument air dryers;
F.
instrument air distribution system, including instruments, valves, piping and supports;
G. Service air distribution system, including instruments, valves, air-line couplings, piping and supports. A ‘priority’ valve shall be included, operable from the CCR, to shut off the supply from the air compressors to the service air system in the event of low pressure in the instrument air header. 6.13.2.1 Sand separators Dust and sandstorms may occasionally occur at site. Occurrence of dust and sandstorms must not compromise compressor operation. One cyclone or equivalent inertial type sand separator per compressor shall be installed. A special motor driven valve for releasing the dust out of the collector and a collecting drum with a minimum volume of 1 m3 shall be furnished with each dust collector. Indication of the dust level inside the sand separator and pressure differential indication shall be supplied. The sand separators and the suction duct shall be installed in such a way that neither dust from ground nor rain water can be drawn into the separator. 6.13.2.2 Suction air filters/silencers
6.13-2 KHABAT TPP UNITS 1&2 - VOLUME I
The suction air filters on each compressor suction side shall retain all dust and sand not collected in the sand separator. They shall be designed for low pressure loss and the compressor design shall be on the basis of the filter being obstructed up to the maximum allowable differential pressure. The suction air filters shall be of the single element dry type. Filter screens shall be quickly changeable or cleanable. Means to indicate when cleaning or replacement is needed shall be provided. The silencers shall be the manufacturer’s standard, specially designed to dampen the low frequency compressor intake noise. The suction air filter/silencers shall be designed for low pressure loss. The compressor design shall be based on the filter being 50% obstructed. 6.13.2.3 Air compressors The compressors shall be of the electrical, direct driven, multi-stage rotary screw type. Oil lubrication of the instrument compressor parts in contact with compressed air is not acceptable. Each compressor shall include a motor, coupling, base plate, lubrication system, water cooling system and all appurtenances. One (1) set of special maintenance tools for compressor overhauling shall be provided. Each compressor shall have the following design features: A.
The period between two inspections for maintenance shall be not less than 10,000 operating hours.
B.
The compressors shall be of heavy duty construction and designed for continuous and intermittent operation at full and low capacity.
C.
The compressors and associated equipment shall be mounted on a fabricated skid base. All piping leaving the skids shall have flexible connections to approval and the piping shall be adequately supported to prevent transmission of vibration and noise.
D.
The compressors shall be of two or three stage configuration water cooled type with intercoolers.
E.
The impeller shall be manufactured from stainless steel.
F.
Bearings shall be lubricated with oil. A lubrication system with a shaft driven pump and an electrically driven pre-lubrication pump shall be supplied.
G. Modulating control shall apply over the full operating range.
6.13-3 KHABAT TPP UNITS 1&2 - VOLUME I
H.
The noise level of the compressors shall not exceed 85 dB(A) at 1 m from the source
6.13.2.4 Air compressor control Each compressor shall have automatic start and stop controls which shall include an unloading device to unload the compressor when it is stopped and maintain that condition until the motor is again up to speed. The compressor shall also be provided with controls which shall unload the compressor when the pressure in the receiver reaches a predetermined level and load the compressor when that pressure drops below a predetermined level without stopping the motor. The pressure controls shall be adjustable over a wide range and shall operate with a maximum pressure change of 0.2 bar. 6.13.2.5 After-coolers One pipeline type after-cooler per compressor with cyclone type water separators shall be provided. The approach temperature, i.e. difference between outlet air temperature and inlet water temperature shall be 6°C for the after-coolers. Cooling water will be inhibited demineralized water of the closed cooling water system. Easy access for inspection and cleaning shall be provided. Drains shall be provided. Each cooler shall be equipped with a relief valve. The after-coolers shall be suitably mounted so as to be accessible for maintenance and inspection. Fouling factors shall be as recommended by TEMA 6.13.2.6 Air receivers The air receivers shall keep an ample amount of air available during short time air consumption peaks to reduce the frequency of compressor cycling whilst maintaining air pressure supplies at or above an acceptable minimum level. Each instrument air receiver will be designed for a storage capacity, without any additional air makeup supply, which is the larger of: A.
Ten minutes storage on normal plant operation or,
B.
The capacity to run down the generating units and station service auxiliaries from full load operating condition to non-operation condition.
Each receiver shall have a pressure gauge and code stamped relief valve(s). 6.13-4 KHABAT TPP UNITS 1&2 - VOLUME I
Design temperature shall be compressor discharge temperature without aftercooling. Each receiver shall be furnished with one (1) snap-action type moisture trap. Each trap shall be provided with a bypass valve. Easy access to the drain valve shall be provided. The bottom of the vessel shall be at least 300 mm above the floor. Each receiver shall conform to the appropriate Codes and Standards and shall be suitable for the site ambient condition specified in Schedule A. 6.13.2.7 Instrument air dryers Two 100% capacity air dryers shall be provided to dry the instrument air. The dryers shall be of the dual tower, regenerating desiccant type each capable of meeting the requirements of the unit instrument air demand and of removing moisture from the instrument air over the range of design ambient conditions specified in Schedule A for the following design instrument air dewpoint: Outlet dewpoint
-40°C
Visual indication of dewpoint shall be given by means of colour change indicators. The dryers shall be packaged self-supporting units, shipped completely piped and wired. The dryer shall have a control cabinet and multiport valves for automatic transfer of air between towers. Each drying vessel shall have a drying capacity equal to ten hours at the rated output and regeneration, including vessel cooling, shall not be more than 6 hours. Moisture shall be removed during regeneration by internal electric heaters and/or purge air and expelled from the vessels to atmosphere by a stream of purge air. The towers shall be fully insulated. In the event that a dryer is supplied without heaters the compressor capacities shall be adjusted for the increased purge air flow. No provision shall be made for by-passing the air dryers. The pressure drop at full load conditions and across the complete dryer/filter package shall not exceed 0.5 bar when clean. 6.13.2.8 Pre and after-filters Each instrument air dryer shall be provided with a pre-filter and after-filter. The pre-filter shall protect the desiccant of the dryer from contaminants such a liquid (water), pipe scale and dirt; while the after-filter shall prevent desiccant 6.13-5 KHABAT TPP UNITS 1&2 - VOLUME I
fines of the dryer from entering the instrument air supply headers. The filters shall be compatible with the dryers in all respects. The water mist removal capacity of the pre-filter shall be not less than 99% and the after-filter shall removal all particles greater than 1.0 micron in size. The pre-filters shall have coalescing elements which will concentrate water mist to bulk liquid for removal by traps. The filters shall have sufficient area so that replacement of cleaning shall be required only at reasonable intervals. Each filter shall be provided with a differential pressure gauge. 6.13.2.9 Drains The compressed air systems shall have drains on all low points. Snap-action type traps with inlet strainers shall be provided. The minimum size shall be 20 mm. Drains from all low points in headers, water separators and air receivers shall empty into waste funnel connections.
6.13-6 KHABAT TPP UNITS 1&2 - VOLUME I
6.13.2.10 Instrumentation and control A. The Bidder shall furnish a complete package of instrumentation and controls necessary to meet the requirements of this specification, and that shall offer a high degree of reliability and safety to both personnel and apparatus. The control system shall include all permissives and interlocks required to ensure safe and proper operation of the compressed air system under all expected normal and abnormal conditions. Abnormal conditions shall be alarmed for operator attention. Instrumentation and controls shall be designed in accordance with the section 8 of this technical specification. B. PLC based control cubicles and complete field instrumentation for the automatically controls and monitoring shall be provided. C. Minimum one(1) operator interface station with dual LCD monitor(21” min.) and printer shall be provided. D. E. The control system shall be designed to enable the operator to supervise and operate the system by using LCD/keyboard in local and OWS in CCR. F. The control system shall be provided with the data communication interface devices with PCS for the supervisory control and monitoring in the central control room.
6.13-7 KHABAT TPP UNITS 1&2 - VOLUME I
6.14
Water Supply and Treatment Systems
6.14.1
Conditions of service
6.14.1.1 Description of service The raw water supplied from great ZAB River is supplied to trash rack. The trash rack shall be installed at the raw water intake structure and discharge structure so as to eliminate foreign matters such as papers, leaves, other refuses from the water channels. The traveling screen removes debris from the influent river water to prevent fouling of the raw water pump. The stop gate is provided for blockade of river water flow at the influent side for the purpose of periodical inspection and maintenance of equipment behind the above equipment. The raw water for the plant shall be supplied by 100% x two(2) raw water pumps into raw water storage tank(30,000m3) in the site. Raw water in the raw water storage tank shall be transferred to the cooling tower make-up by 30% x three(3) cooling tower make-up pumps and transferred to the water treatment system by 100% x two(2) raw water transfer pumps. The pipe line size is 150mm nominal diameter and the flow rate is approximate 140m3/hr. The raw water in the raw water storage tank is transferred to clarifier by raw water transfer pumps and is pretreated with chemicals to remove suspended and dissolved solid. the pretreated water by gravity filters is stored in the filtered water reservoir. The filtered water in filtered water reservoir is transferred to the make-up demineralizer system by Demi. Water supply pumps and that is demineralized by the make-up demineralizer system and stored into the demi. water storage tank. Also, the potable water will be supplied by the potable water pumps from the filtered water reservoir. The raw water, make-up demineralizer, potable water & service water system shall be incorporated in the drawings and requirements specified in this specification. A. Normal Operation 1) The raw water in the raw water storage tank is transferred to the clarifier by the raw water transfer pumps. The floc. in the clarifier shall be created by the clay and the chemical which is included in alum, alum aid, caustic and the clarified water shall be monitored by turbidity control and removed suspended and dissolved solid in the clarifier. 6.14-1 KHABAT TPP UNITS 1&2 - VOLUME I
2) The slurry water on the bottom of clarifier shall be transferred to waste water treatment system by sludge transfer pumps. 3) The clarified water is delivered into three(3) 50% capacity gravity filters. 4) The bypass line to avoid clarifier shall be considered. 5) Filtered water to be used for the make-up demineralizer system is stored by gravity in the underground filtered water reservoir. 6) The water in the filtered water reservoir is transferred to demineralizer trains by Demi. Water supply pumps. 7) Each of the demineralizer trains shall include an activated carbon filter to remove any trace of organic matters and residual chlorine. The activated carbon filters shall be backwashed by back washing pumps. 8) The pretreated water from activated carbon filter shall flow through cation exchanger, degasifier, anion exchanger and mixed bed exchanger. The demi. water supply pumps and the degasified water transfer pumps shall be sufficiently designed to deliver the pretreated water into the demi. water storage tank . 9) Potable water shall be supplied to the activated carbon filters by potable water pumps from filtered water reservoir and it shall be removed color, taste, turbidity, organic matters by the activated carbon filters. Potable water chlorinated by sodium hypochlorination feed pumps will be stored in the hydropneumatic tank and supplied to demand area. 6.14.1.2 Design conditions A. Design Parameters 1) General a) General design conditions Pressure, kg/㎠.g
10.0
Temperature, ℃
Max 66.0
b) Auxiliary steam conditions Pressure, kg/㎠.g
6
Temperature, ℃
180
2) Raw Water Supply System a) Raw Water Pumps 6.14-2 KHABAT TPP UNITS 1&2 - VOLUME I
•
Quantity : Two (2)×100% capacity / 2unit
•
Raw water pump shall be capable of pumping one(1) day required water for two(2) units within 8hrs.
•
Design Head : The system head based on the highest point on energy gradient for the minimum depth of the liver condition.
b) Raw Water Storage Tank •
One(1) 100% capacity / 2 unit
•
Carbon steel construction with painting
•
SP-10 inter surface treatment and epoxy coating
•
Outside painting
•
30,000m3 capacity available
•
All required instrument and level control equipment
c) Intake equipment (for 2Units) •
Intake structure
•
Traveling screen : Two (2) sets
•
Trash rack : Two (2) sets
•
Stop gate : Two (2) sets
•
Embedded Guide for future units : Three(3) sets
d) Screen wash pumps •
Quantity : Two (2)×100% capacity / 2unit
•
Type : Centrifugal
e) Cooling tower make-up pumps •
Quantity : Two (2)×100% capacity / 2unit
•
Type : Centrifugal
f) Raw water transfer pumps •
Quantity : Two (2)×100% capacity / 2unit
•
Type : Centrifugal
3) Raw Water Pretreatment System and Potable Water System a) Clarifier •
Upward velocity of effective
2.44
area, at max. flow ,㎥/hr.㎡ •
Flow rate, ㎥/hr
•
Minimum detention time at
140 60
maximum flow, minutes. •
Number of clarifier
1
6.14-3 KHABAT TPP UNITS 1&2 - VOLUME I
b) Gravity Filters •
Capacity each of filter, ㎥/hr
70
•
Linear velocity of filter cross-
7.32
sectional area, ㎥/hr.㎡ •
Backwash linear velocity of filter
29.4
cross-sectional area, ㎥/hr.㎡ •
Number of filters
•
Design pressure, kg/㎠.g
Atm
•
Minimum depth of media
m
3
media : Amthrecite, Sand c) Activated Carbon Filters for Potable Water •
Number of filters
•
Linear velocity of filter
2 12
cross-sectional area, ㎥/hr.㎡ •
Flow rate, ㎥/hr./filter
20
•
Backwash linear velocity of filter
24.4
cross-sectional area, ㎥/hr.㎡ •
Design pressure, kg/㎠.g
10
d) Hydro-Pneumatic Tank for Potable Water •
Type
•
Number of tank
•
Material
•
Capacity, ㎥
Horizontal 1 STS or equal 15
e) Hydro-Pneumatic Tank for Service Water •
Type
•
Number of tank
•
Material
•
Capacity, ㎥
Horizontal 1 Carbon steel 20
4) Makeup Demineralizer System a) Activated Carbon Filters •
Number of filters
2
•
Linear velocity of filter
11
cross-sectional area, ㎥/hr.㎡ •
Flow rate, ㎥/hr./filter
32
•
Backwash linear velocity of filter
24.4
cross-sectional area, ㎥/hr.㎡ 6.14-4 KHABAT TPP UNITS 1&2 - VOLUME I
•
Design pressure, kg/㎠.g
10
b) Degasifiers •
Number of degasifiers
2
•
Capacity, ㎥/hr/ea
32/ea
•
degasifier air blower (q'ty)
2
c) Exchangers •
Ion Exchange Using Exchange Capacity and Chemical Consumption Anion
Cation Exchanger Minimum exchange ability,
Exchanger
-
Mixed Bed Exchanger
-
-
g as CaCO3/l-resin Maximum dosage of 100% HCl, -
-
g/l-resin Maximum dosage of 100% NaOH,
-
-
g/l-resin Minimum ion exchanger
768
768
768x5
unit capacity, ㎥/regeneration Minimum resin depth, m •
0.91
0.91
0.91
Resin Inventory The primary resin beds shall be designed based on the maximum water analysis for 24 hour runs between regenerations. The mixed-resin bed strong-acid to strongbase resin stoichiometric ratio shall be 1 : 1. The minimum resin depth shall be 0.91m. o Cation Exchange Resin Strong acid, gel type, cation resin is required having a polystyrene-DVB copolymers matrix and sulfuric acid functional groups. The resin shall be standard Dowex HCRS or Amberlite IR-120 or Duolite C-20 or equal, shipped in the hydrogen form. o Anion Exchange Resin Strong base, gel type, anion resin is required with polystyrene-DVB
copolymers
matrix
and
quaternary
6.14-5 KHABAT TPP UNITS 1&2 - VOLUME I
ammonium functionality. The resin shall be standard Dowex SBR-P or Amberlite IRA-420 or Duolite A-101 or equal, shipped in the chloride form. o Flow rate, ㎥/hr,㎡ - Cation
:
20
- Anion
:
10
- Mixed Bed
:
30
o Product flowrate, ㎥/hr.train
:
32
o Design pressure, kg/㎠.g
:
10
o Minimum diameter of demineralizer vessel - Cation, diameter, mm
:
- Anion, diameter, mm
:
- Mixed bed, diameter, mm
:
6.14.1.3 Performance A. The Bidder shall Performance the following effluent qualities by treating the raw water. 1) Clarifier - Flow rate, ㎥/hr
140
- Turbidity, NTU
< 5.0
2) Gravity Filters - Flow rate, ㎥/hr.filter
70 X 3(1 Stand-by)
- Turbidity, NTU
< 1.0
3) Activity Carbon filter fo Potable Water System - Flow rate, ㎥/hr.filter
20
4) Makeup Demineralizer System - Flow rate, ㎥/hr.train
32
- Accumulated flow rate, ㎥/regen
768(32 x 24h)
5) Quality of Make-up Demineralizer Water The quality of demineralizer water shall be as follows : Anion Exchanger
Mixed Bed Exchanger
(Effluent)
Constituents Total suspended solids, ppm
0.1
Max. 0.1
Total hardness, ppm as CaCO3
0.0
0.0
Carbon dioxide, ppm
0.0
0.0
Total silica, ppm as SiO2 +
Sodium, ppm as Na
Max.
(Effluent)
Max. Max.
0.2
Max. 0.02
0.9
Max. 0.01
6.14-6 KHABAT TPP UNITS 1&2 - VOLUME I
Conductivity ,
Max.
10
Max. 0.2
Micromhos/cm at 25 ℃ pH at 25 ℃
6.5 - 7.5
6) The ion-exchange resins in the demineralizer system shall be guaranteed not to have lower than a capacity at the maximum chemical dosages specified in this specification. However, the regeneration system shall be enough designed so that the chemical dosages could be doubled at operator's option. These guarantees shall be based on the influent water analysis specified in design data and shall consider the additional ionized salts which is caused by chemical addition through pretreatment. 6.14.2
Design and construction features
6.14.2.1 General A. The raw water pretreatment and makeup demineralizer system shall be designed so as to insure continuous, safe, and economical operation providing the maximum reliability without vibration or noise. B. Duplication of components shall be maximized to the greatest extent possible such that similar components shall be interchangeable. C. Each item of raw water, potable water, service water and makeup demineralizer system equipment shall be shop assembled, properly aligned, and, if required, match-marked and disassembled for shipment. D. The equipment and all assembly joints or junctions shall include alignment or centering fits as required to ensure accurate reassembly or alignment of all parts. E. The Bidder shall make any provision for the future area of the water treatment system supplied by KNOC. 6.14.2.2 Raw water supply sytem and intake equipment A. Raw Water Pumps 1) The river water may at times contain sand, shells, marine life and debris of size that will pass through the 9.525mm (3/8 inch) mesh travelling screens for the raw water pump. 2) The pump shall be designed in accordance with the recommendation of the design standard of the Hydraulic Institute Standards. The Bidder shall design the pump and motor selected to meet the
6.14-7 KHABAT TPP UNITS 1&2 - VOLUME I
specified intake structures and cooling tower structures design conditions. 3)
For system designs which include pumps in parallel operation each pump shall be capable of continuous operation at maximum run-out condition
4) The pump head-capacity curve shall be continuously rising from the maximum flow to shutoff. 5)
Pump design pressure shall not be less than the shutoff head.
6)
The first critical speed of the pump shall exceed the operating speed of the pump by at least 25 percent. Critical speed shall include effects of lubrication, bearings and bearing supports.
7)
The pump and motors shall be capable of withstanding without failure such design conditions including reverse rotation due to power failure.
8) The Bidder shall perform the vibration analysis of pump station and shall have responsibility to modify any harmful effect from vibration. The vibration analysis for each pump shall include the analysis for the operating conditions of starting, stopping and trip. B. Intake Equipment 1) The traveling screen remove debris from the influent river water. The trash rack shall be installed at the riverwater intake structure, circulating water intake structure and discharge structure so as to eliminate foreign matters such as papers, leaves, other refuses from the water channels. 2) The stop gate is provided for blockade of riverwater flow at the influent side for the purpose of periodical inspection and maintenance of equipment behind the above equipment. The equipment shall conform to the design and arrangement indicated on the drawings and requirements specified in specifications. The Bidder shall supply and install the embedded guide materials for future units. a) Through-flow type traveling screens complete with all accessories : •
Splash housing
•
Head shaft drive
•
Screen wash spray system
•
Screen frame and embedded guides
•
Baskets and carrying chains 6.14-8 KHABAT TPP UNITS 1&2 - VOLUME I
•
Screen drive motor and reducer
b) Trash rake complete with all accessories : •
Traversing head frame and dead plate
•
Hopper
•
Hoisting mechanism
•
Motors and gear reducer
•
Cable reels and cable
•
Motor starters, switch-gear and wiring
•
Runway rail
c) Trash racks complete with all accessories. •
Trash racks
•
Embedded materials
d) Stop gates complete with all accessories. •
Stop gates
•
Guide ways
3) The equipment shall not require service water. If service water is required, the equipment shall be designed to use source water as service water. 4) Travelling screen a) The screen shall be the vertical, traveling basket, through-flow type of the manufacturer's proven design and construction, modified to meet the requirements of the specified service and this specification. The screen shall be situated with the main bearings and shaft above the mean low water level, shall be of the selfcleaning, two speed type, suitable for unattended operation. b) Allowable stress in structural members, screen frames, or panels shall not exceed AISC values for the material used. These shall be based on the load corresponding to a combination of maximum upstream water depth, the differential head obtained at stalled motor torque, and a coefficient of friction for carrying chain rollers of 0.13. Spray header piping and connections shall conform to ANSI Standards. Drive gearing shall conform to AGMA Standards. c) Screen drives shall be designed for continuous operation at all specified speeds under the loading imposed by rated upstream water level and the head differential across the screens. When subjected to the maximum breakdown(stalling) torque of the drive 6.14-9 KHABAT TPP UNITS 1&2 - VOLUME I
motor, all screen drive components, including screen carrying chains, shall have a factor of safety of not less than 3 based on the ultimate or fracture strength of the material. Allowance for failure of a shear pin shall not be included in this requirement except on written permission of the KNOC. d) The screen approach velocity shall not exceed 0.8 m/s with a corresponding pressure drop of not more than 150 mm water level across the screen, with a minimum water level in the screen forebay and with 30% of the screen blocked. e) Allowable stress in structural members, screen frames, or panels shall not exceed AISC values for the material used. These shall be based on the load corresponding to a combination of maximum upstream water depth, the differential head obtained at stalled motor torque, and a coefficient of friction for carrying chain rollers of 0.13. f) Spray header piping and connections shall conform to ANSI Standards. g) Screen panels shall include full width self draining rubbish elevators to be installed at intervals around the internal periphery of the screen. The rubbish elevators shall be manufactured from the same material as the screen panel. The screen panels shall be electrically isolated from the main structure. h) The traveling screen operation shall be controlled and monitored from the PCS. i) Drive gearing shall conform to AGMA Standards. 5) Trash Racks a) The trash rack shall be made by welding flat bars to horizontal beams at a specified pitch and the trash rack shall be hinged to the bracket in the screen wall. b) The trash rack shall consist of vertical steel bars with sufficient horizontal support structural beams and spacers. It is very important point in design to maintain the uniform space between the bar through entire trash rack to provide efficient collecting of refuses. 6) Trash rake
6.14-10 KHABAT TPP UNITS 1&2 - VOLUME I
a) The trash rake shall consist of a rake proper, hoist mechanism, mechanical or hydraulic system for positioning rake teeth, trash hopper, carriage drive and cable reel type power pickup. b) Trash rake shall be of the cable operated rake type, non guide design. Hoist and carriage drives shall be electrically operated. c) Trash pit will be installed at one side of each main intake structure. And a trash rack rake will remove its trash into this pit. The Bidder shall install necessary rail including embedded hardware and shall consider sufficient length of cable or travelling mechanism. d) The rake shall be raised and lowered through a suitable system of cables, sheaves, hoist drum, gear reducer and electrical motor. A suitable power-operated mechanism shall be provided to engage and disengage the rake teeth. The entire unit, including trash hopper, shall be electrically driven along rails by a suitable reversible gear motor drive.
A brake shall be provided to lock the
wheels when not in use. The rake shall be designed to be used and stored outdoors. 7) Stop Gate a) The stop gates shall be designed based on the water levels from bottom sill to H.W.L. b) Each stop gate shall be of welded construction and consist of a structural steel frame formed by 2 vertical end girders between which horizontal beams are properly spaced according to their individual capacity and design water pressure. The end girders shall be provided with substantial bearing plates to distribute the load to the embedded parts and with suitable adjustable guide shoes to position and guide the stop gates within the embedded parts. The end girders shall transmit the design loads to the embedded parts without warping or undue to deflection. c) The entire downstream face shall be covered with a heavy steel skin plate. d) Each stop gate shall be designed to close under its own weight with balanced no-flow hydraulic conditions. e) Bottom section stop gate shall be have gate valve to equalize hydrostatic water pressure prior to lift up stop gate. The valve
6.14-11 KHABAT TPP UNITS 1&2 - VOLUME I
should be installed at the appropriate at point of bottom section of stop gate. f) The valve shall be specified to be operated through the lifting beam that is controlled from the gantry crane. g) The stop gates shall be of the sliding vertical lift type with downstream seals. In these specifications, the downstream side of the stop gate refers to the unwatered side in the closed position. h) Drain holes to adequate size shall be located in the webs of horizontal beams to completely drain the water from these beams. i) Each stop gate shall be provided with lifting lugs to engage with the lifting hooks of the lifting device. j) Each stop gate shall be sealed at the downstream face with J-type neoprene seals & wedge seal between the stop gate and embedded material so that when properly in position the set of stop gates are free from leakage. k) The seals shall be in continuous lengths where possible and any necessary joints shall be properly made to be watertight and of adequate strength. The seals shall be fastened to the stop gate of stainless steel bolts and nuts to facilitate their replacement. The seals shall be positive in action and shall not unduly interfere with the placing and withdrawal of the stop gate. l) The guides shall be fabricated from suitable material of channel sections and fully grouted with the foundation by welded grouting lugs on the back of the channel sections. The channel sections shall be arranged to give an adequate and permanent location. The tops of the side guides shall be fabricated to give sufficient lead-in to enable the stop-gate to be correctly positioned over the guides. m) Where the rubber seals are located in the guide frame, stainless steel strips shall be provided, the strips may be welded to the channel section by an approved procedure. 8) Splash Housing a) Splash housing shall be provided to enclose the spray system and refuse trough. The housing shall be watertight and provided with hinged and gasketed inspection door.
6.14-12 KHABAT TPP UNITS 1&2 - VOLUME I
b) The rear of the housing shall be removable for access to the screen chain and baskets. c) The arrangement of the housing shall provide for the full opening of the inspection door between adjacent units. 9) Head Shaft Drive a) The head shaft drive shall be the roller-chain type, oil-bath lubricated, and located outside the splash housing in a suitable oiltight enclosure. The enclosure shall be provided with an oil-level sight gage and bottom drain cock. b) The driver shall be a two speed electric motor giving a speed ratio of no less than 2:1. c) A shear pin or approved slip type coupling device shall be provided on the reducer drive sprocket. If shear pins are used, 16 Set(s) extra pins for each size required shall be provided. d) The drive chain shall be furnished with a 12 gauge stainless steel protection guard. 10) Spray System a) The spray system shall be the single header type. b) The spray header shall terminate with a power-operated butterfly valve outside the splash housing for connection to wash water source. Wash water will be provided after having passed through a duplex basket strainer with perforations no larger than 4.5 mm. Valve connection shall be flanged per ANSI/ASME B16.5. 11) Frames a) Screen framework Sections shall be approximately the same length. The head shaft section shall have adequate lifting lugs to enable lifting of the entire assembly. b) The main frame of screen shall be of four(4) post construction with overlapping side guard seals to prevent debris from passing through the chain link and around the outside of the screen frame. c) The raw water pump area screen assemblies shall be designed and fabricated to permit installation and removal by using gantry crane. Bottom frame sections shall have supporting and lifting lugs as required for installation or removal. d) Frame sections shall be of welded and/or bolted construction insofar as practicable. All shop frame joints shall be continuously 6.14-13 KHABAT TPP UNITS 1&2 - VOLUME I
seal welded to eliminate crack corrosion. All field connections shall be bolted. e) Cross bracing shall be provided if required to maintain rigidity and running clearances under maximum differential level operation or to limit combined stresses to allowable limits. However, no material thickness shall be less than 10 mm. f) Renewable chain tracks or guides shall be provided on the ascending and descending side of the framework. g) If required by seismic design, the descending side of the framework may require a guide. h) The Bidder shall provide wall guide ways and anchors for placement in the screen structure wall at the time the structure is poured. The guides shall be transported to the jobsite before the screen assemblies in accordance with the delivery schedule. i) The screen frame shall be adequate to resist the maximum differential head necessitated by the Bidders design or 2 m differential head, whichever is greater. j) The screen panels shall provide for an easy assembly of kelp knives on alternate screen panels. No kelp knives shall be required initially with this equipment. 12) Baskets and Carrying Chains a) Screen mesh for baskets shall not be less than 14 Washburn & Moen wire gage with 10mm square clear openings. The loading that the wire mesh imposes on a basket-carrying frame shall be considered in the frame design. b) Basket frames shall be attached to carrying chains to transfer uniform loading to the chain rollers. c) Screen carrying chains shall be the hardened roller type with ground bushings and pins that have water-tight press fits into chain sidebars. Grease fittings shall be provided for lubrication of bushing wearing surfaces. The screen drive chain shall be heavy duty, steel, roller type. d) Head shaft sprockets for basket-carrying chains shall be provided with renewable, hardened inserts to absorb wear from chain rollers. The headshaft shall be provided with sleeve type bronze bearings mounted in guided ways arranged for adjustment of 6.14-14 KHABAT TPP UNITS 1&2 - VOLUME I
carrying chain tension. Grease fittings shall be provided for the lubrication of head shaft bearings. Foot shaft bearings shall be sleeve type, self-lubricated suitable for underwater service. e) Effective seals shall be provided to prevent passage of trash through or around carrying chains and chain guides also to prevent passage of solids as the screen baskets pass around the foot wheels. f) Shoes shall be provided on the basket framework if stress limitations require center support for the baskets. The shoes shall slide in guides to be provided on the main structural framework. g) Portable chain-tension indicators of the manufacturer's standard design shall be furnished as called for in the material requisition. The devices shall be calibrated for accurate indication. Calibration certificates shall be furnished by Bidder for each device. 13) Motor and Reducer a) The screen drive motor shall be in accordance with NEMA design "B". The motor enclosure shall be TEFC. All drive components shall be designed to withstand the full NEMA stalling torque of the motor without damage to any part of the drive or the foot shaft assembly. The drive shall be capable of starting the screen under a load equivalent to a 760 mm water pressure differential at the high water levels.
The drive unit shall be suitable for screen
travel speed of 3 m/min. b) The drive unit speed reducer shall be a fully enclosed helical gear type with anti-friction bearings. The speed reducing gear shall be connected to the drive motor by non-lubricated stainless steel, disk-type flexible coupling and through keyed shafts. c) Cover guards shall be provided for all motor and speed reducer couplings. 14) Trash Rack a) The trash rack and embedded material shall be designed as a normal load condition for the design differential head. b) The trash rack should be installed vertically at a slight angle of 5 deg from the vertical toward the pump and the discharge structure trash rack should be installed in same location of stop gate vertically. 6.14-15 KHABAT TPP UNITS 1&2 - VOLUME I
c) Trash rack shall consist of a series of equally spaced vertical flat bars supported by a structural frame consisting of two vertical end girders between which horizontal beam shall be located to meet the water pressure and flow conditions. d) The frame, end girders, beams and bars shall be welded together. e) The unsupported length shall be restricted by bar vibration. f) At the design differential head, stress in the trash rack bars shall not exceed 90% of yield stress. g) The trash rack guides shall be consist of vertical steel members embedded in concrete including all anchor bolts. 15) Trash rake a) Hoisting Machinery The hoisting machinery shall consist of a motor with motor brake, gear reducer, limit switch, line shaft, bearings and hoisting drums of sufficient size to store all required hoisting cable without overlap. Trash rake assembly shall be provided with two cast irons grooved hoisting drums and supported by self-aligning roller bearings. Each drum shall be provided with stainless steel wire rope cables. The hoisting cables shall have a minimum breaking strength of 5 times the design lifting capacity. The limit switch shall be mounted at one end of the shaft for automatically stopping the rake at the top and bottom of the travel. The motor brake shall hold the rake in any position when power is removed. Full personal protection cover guards shall be provided for all motor and speed reducer couplings. b) Raking Mechanism The raking mechanism shall be driven from the hoist through a suitable system of cables and sheaves. The support of the raking mechanism shall be by four(4) cables of stainless steel. The rake teeth shall be spaced to correspond with the spacing of the bar rack. The rotation of the rake teeth shall be accomplished by changing the effective length of the cables by a mechanical-hydraulic 6.14-16 KHABAT TPP UNITS 1&2 - VOLUME I
mechanism with this effective change in cable length, the mechanical linkage within the trash rake will rotate the teeth to the cleaning position. Reversing this cycle at the top of the run shall cause an effective discharge of the debris. The design of the tooth rotating mechanism shall also permit opening and closing of the rake teeth at any point in the raking cycle with the rake stationary or in motion. The rake shall have a load lifting capacity of 2600 kg and shall rake at a speed of approximately 9 m/min. The round bar rake teeth shall penetrate the upstream face of the trash rack by about 20mm and shall be of stainless steel. c) Traversing Mechanism The entire unit shall be electrically driven along the rails in a horizontal direction by a reversible drive unit. The wheels shall be cast iron and keyed to the shafts. Each shaft assembly shall be mounted to the shafts. Each shaft assembly shall be mounted to the main frame by two self-aligning roller bearings. The operation of the traversing drive shall be by means of holddown "forward" and "reverse" pushbuttons. Traversing motor shall be provided with a motor brake to stop and hold the drive unit when the pushbutton is released. The rails and rail clips upon which the trash rake equipment moves and operated shall be of carbon steel. The reducer for the traversing drive unit shall be a vertical worm gear type. The motor brake shall be dust-tight, waterproof magnetic disc type mounted to the motor, and shall be suitable sized to keep the unit stationary. The traversing speed shall be approximately 9 m/min. d) Framework The main frame of the trash rack shall be designed to fit the raking mechanism. The framework shall consist of the main frame, dead plate assembly, wheel guides, machinery platform, and debris Hopper. The dead plate located on the front of the main frame shall assure smooth transition of the rake mechanism from the bar 6.14-17 KHABAT TPP UNITS 1&2 - VOLUME I
rack to its discharge position. The design of the dead plate shall allow for operation over 90cm high pipe handrail at the edge of the operating floor, and discharge into the debris hopper. The debris hopper shall be of 2m3 capacity stainless steel and shall be of the hinge open type, for discharge into a refuse trough. e) Hydraulic Control System The hydraulic unit shall include a TEFC motor having class "B" insulation with hydraulic pump, reservoir, relief valve, solenoid valve, flow control valves, hydraulic tubing, piping, valves, etc., to provide complete hydraulic system. A relief valve in the hydraulic mechanism shall be factory set to open, allowing the rake teeth to open when the rake become jammed or otherwise overloaded. Each system shall be furnished with two cylinders for operation of the walking beams. C. Screen Wash Pumps and Equipment 1) Design of Condition a) Two (2) 100% duty/standby wash water pumps, together with auto clean strainers and associated interconnecting pipework and equipment shall be supplied and installed as part of the Works for each drum screen. b) The pumps shall be located adjacent to the drum screens. The pumps shall draw their water from the clean water side of the drum screens, and shall be designed to provide the spray/wash water requirements of the drum screen, with minimum water level in the suction chamber. c) The screen water jet system offered shall be capable of flushing all debris into a collecting trough and washing it away to the sea. The jets and isolating valves (one per jet) shall be readily accessible and easily removable for clearance of any blockage that may occur. Splashguards shall be provided over pipework and nozzles with doors or removable panels to allow viewing of each washwater jet and to provide access for maintenance. d) Nozzles for the wash water system shall be constructed from a suitable material to avoid corrosion. Nozzles shall be easily 6.14-18 KHABAT TPP UNITS 1&2 - VOLUME I
replaceable. Pumps, pipes and valves shall be in accordance with the general requirements of this specification. e) The debris collection trough system shall be fabricated from grade 316 stainless steel. The collection troughs supplied with the drum screen structure shall be securely supported and suitably designed to enable easy replacement. f) The debris collection trough from the screen shall direct the collected debris and wash water into a common disposal trough fabricated from 316 stainless steel and this debris shall discharge to an approved location. D. Instrumentation and Controls 1) General a) The Bidder shall design and supply all instrumentation and control system so as to insure accurate, safe and reliable operation under conditions of service. b) The Bidder shall be responsible for the design to meet the requirements of system performance. Any additional designs required to satisfy the high efficiency, equipment and system protection, safety and stability operation requirements shall be provided at no additional cost. c) All automatic and manual control action of intake equipment shall be possible through PCS (except for trash rake). d) All instrumentation and control equipment shall be supplied. If any requirements given in this specification, the instrumentation shall be supplied in accordance with in this requirements. 2) Scope The work to be furnished by the Bidder per Units shall include, but not be limited to the following; a) Local control station for TWS b) Level monitoring equipment with monitoring panel c) All instruments and related accessories, erection materials for installation of instruments, etc. d) Instrument cabinets to mount transmitters, switches and other local instruments.
6.14-19 KHABAT TPP UNITS 1&2 - VOLUME I
e) Two(2) channel signal distributers of level signals of after TWS, Two(2) channel signal distributer of common level signal of before TWS f) others 3) Design requirements a) General requirements The Bidder shall furnish a complete package of instrumentation and controls necessary for the TWS to function in a manner that will meet the requirements of this specification, and that will offer a high degree of reliability and safety to both personnel and apparatus. The sequencers shall have the capability of turning on and off on to four times each 24 hours for periods of time varying from 1-1/3 revolutions to continuous operation. The screen wash cycle shall be automatically initiated upon attainment of a preset differential level across to screens. The screen wash cycle shall be initiated automatically on high differential head across the screens, with automatic pump shutdown when the wash cycle is complete. Concurrently, the screen shall revolve at least 1-1/3 revolutions to provide complete basket cleaning and to prevent debris from standing and drying out on the screens. The wash cycle shall also be started and stopped manually. Local control stations shall be provided for each screen drive and for each power operated valve. b) Level measuring equipment with monitoring panel The Bidder shall furnish ultrasonic level measuring equipment with all necessary accessories of traveling screen control. Level monitoring panel shall indicate the level of sea water level and differential level between before and after screen. Level monitoring panel equiped with level measuring equipment and accessories hall be the self standing type and its enclosure type shall be above NEMA 4X. c) Field Instrument Requirements Instrument shall be supplied by one(1) recognized manufacturer having wide experience in the manufacture, application as possible. 6.14-20 KHABAT TPP UNITS 1&2 - VOLUME I
d) Local control station Local control station shall be the self standing type and its enclosure type shall be above NEMA 4X. The Bidder shall provide local control station of TWS to be controled by the operator locally. Local control station shall be equiped with control switchs and lamps for manual and jogging operation of TWS. 6.14.2.3 Raw water pretreatment system and potable water system A. Clarifier and Related Equipment. 1) One(1), 100% capacity clarifier shall be provided and shall be of the circular type, sludge recirculation and conical base. Appurtenances consist of chemical mixing zone and feed facility, sludge handling facility with mixing, reaction and separation compartments. Minimum detention time shall be 60 min. with upward velocity 2.44 ㎥/hr.㎡ of rise area. 2) The agitator mechanism shall be mounted on top of the clarifier and shall be complete with shaft, paddles, lubricated bearings, adjustable speed drive, gear reducer, and automatic torque releasing mechanism with alarms. The contents of the reaction zone must circulate to cause flocculation of all particles while they are kept in suspension. The large volume of floc previously formed from the stilling flocculation zone shall be recirculated. The system shall be designed so that all portions of floc are agitated to avoid the formation of cones or pockets. 3). Automatic blow-off equipment, actuated by flow or time for sludge removal shall be provided and furnished complete with adjustable timers by using program, control valves, tank dewatering provision. 4) A structural steel walkway and stairway shall be provided, and the walkway shall be extended to the full diameter of the clarifier. The walkway and stairway shall be provided with kick plates and handrails. 5) Two(2) 100% capacity sludge transfer pumps shall be provided. 6) The shell and bottom of the clarifier shall be fabricated of A 285 Gr.C or equal in accordance with API 650. The clarifier interior shall be coated with 0.3mm of polyamide epoxy. B. Gravity Filters 6.14-21 KHABAT TPP UNITS 1&2 - VOLUME I
1) Three(3), 50% capacity gravity filters shall be provided and shall be of the vertical type, skid mounted, preassembled, piped, wired and tubed. 2) The gravity filters shall contain multiple media and be furnished in accordance with AWWA standards for filtering material. Support media shall be provided, if required. Each filter shall be equipped with all automatic valves required to operate the unit. Service, backwash, rinse and drain valves shall be the automatic butterfly type. 3) Two(2), 100% capacity gravity filter back wash pumps shall be provided. 4) The gravity filter shells shall be fabricated of A 285 Gr. C or equal in accordance with API 650. The vessel interior shall be lined with 0.3mm of polyamide epoxy. The internal upper and lower distributors shall be constructed of extra heavy carbon steel lined with 0.3mm of polyamide epoxy and shall evenly distribute all flows. Internals shall be factory assembled. C. Chemical Feed System 1) The Bidder shall design that the alum aid with electric heater and the alum (solid drug) are melted by the agitator in the dissolving tanks. 2) The caustic(45% liquid) is diluted in the mixing tank. 3) Chemicals shall be delivered in site with bags or containers and dissolved or diluted in the chemical tanks by the agitator. 4) Each tank shall be provided with overflow, drain, and fill connections. and steel tanks shall be provided with hinged cover, bottom dished head etc. The tank capacity shall be sufficient for one day's usage. 5) Slow speed(75 rpm maximum) agitator shall be provided on the related tank. 6) Two(2) flooded suction positive displacement, diaphragm type pumps or KNOC approved equal pumps shall be provided for each chemical. 7) The feeder equipment shall be mounted above skid and assembled with suction and discharge piping. 8) The alum, alum aid and caustic tanks shall be constructed of 316 stainless steel(mininum 3.2mm thickness) or equal. Wetted parts of the alum, alum aid and caustic feed pump shall be constructed of 6.14-22 KHABAT TPP UNITS 1&2 - VOLUME I
316 stainless steel or teflon or equal. Piping shall be schedule 40, 316 stainless steel or hard rubber lined carbon steel or equal. The alum and alum aid tanks shall have a capacity included the usage of waste water treatment system and shall be supplied from branch lines by each feed pump. D. Potable water system 1) The chlorination system shall be able to chlorinate the potable water when the power plant is operating normal at a rate of 20 ㎥/h. Chlorine dosages of 0.2 to 0.1ppm of free available chlorine will be required. 2) Sodium hypochlorite will be supplied by sodium hypochlorite feed pumps from sodium hypochlorite feed tank. The Bidder shall supply discharge piping of sodium hypochlorite feed pumps and a mixing tee. Sodium hypochlorite feed tank shall be designed to include drug capacity of raw water pretreatment system. 3) The Bidder shall adequately size the hydropneumatic tank. 4) The Bidder shall furnish the instrument air piping and valves. 5) Hydropneumatic tank internal pressure shall be maintained by pressure regulation valve and non-slam check valve on the air line from service air header. The Bidder shall also furnish all necessary instruments and controls required for full automatic operations of this equipment. 6) Hydropneumatic tank shall be constructed by ASTM A240 type 304. 7) Two(2) 100% capacity activated carbon filters, the internal upper and lower distributors shall be fabricated of A240 type 304 in accordance with ASTM code. Internals shall be factory assembled. 8) The flow integrating indicator to be installed on the discharge of hydropneumatic tank shall be supplied by the Bidder. E. Service water system 1) The Bidder shall adequately size the hydropneumatic tank. 2) The Bidder shall furnish the instrument air piping and valves. 3) Hydropneumatic tank internal pressure shall be maintained by pressure regulation valve and non-slam check valve on the air line from service air header. The Bidder shall also furnish all necessary instruments and controls required for full automatic operations of this equipment. 6.14-23 KHABAT TPP UNITS 1&2 - VOLUME I
4) Hydropneumatic tank shall be constructed by carbon steel. 5) The flow integrating indicator to be installed on the discharge of hydropneumatic tank shall be supplied by the Bidder. 6.14.2.4 Makeup demineralizer system A. Makeup Demineralizer 1). The makeup demineralizer system shall consist of following components: a) Two(2) 100% capacity activated carbon filters b) Two(2) 100% capacity cation exchangers c) Two(2) 100% capacity degasifiers d) Four(4) 100% capacity degasified water transfer pumps (Two(2) 100% capacity per train) e) Two(2) 100% capacity anion exchangers f) Two(2) 100% capacity mixed bed ion exchangers 2) The two(2) train demineralizer system shall be capable of operating with one train in service while one train is regenerating. During normal operation, one train will be on line with the other on standby. During peak water demands, the system shall have the capability of operating two trains simultaneously. 3) All demineralizer vessel internals shall be designed to adequately distribute and collect the flow without channeling or bypassing and without loss of resin. All internals shall be designed to be removed through the vessel access manhole. 4) The under drain system shall be designed : a) To ensure that there are no inactive resin volumes b) To retain resin fineness less than 50 mesh c) Without sub fill 5) A resin trap shall be furnished in the effluent line of each ion exchanger. The trap basket shall be capable of withstanding a differential pressure of 10.0 kg/sq.cm.g without failure. The resin trap body shall be constructed of rubber lined carbon steel. The basket shall be stainless steel with 100 mesh effective screen size. 6) Each vessel shall be furnished with the following accessories : a) Structural support legs b) One access manhole, 500 mm minimum diameter c) Vent valve to vent the highest point in the tank or piping 6.14-24 KHABAT TPP UNITS 1&2 - VOLUME I
d) Drain valve e) Sight glasses in all backwash lines located down-stream of the rinse line connection f) 75 x 300 mm sight glass in all demineralizer vessels at the settled bed level and at the top of the bed for use during backwash and at mixed resin interface for mixed bed ion exchanger. g) 150 mm flange openings to enable sluice-out of resin h)
A
drain-down
connection
on
each
mixed
bed,
suitably
screened(316 stainless steel) located at the point of drain-down required for proper mixing. Minimum size of drain connection shall be 65 mm. Bidder shall provide a screened pipe probe internally, if required. i) A sampling point shall be provided for the effluent of each in exchanger vessel and activated carbon vessels. B. Regeneration 1) The Bidder shall furnish a complete system for automatic and counter current regeneration of the demineralizer system. The system shall include chemical storage and injection tanks, injection pumps, unloading and transfer pumps, piping, valves, instrumentation, mixing tees and steam water heater, and other components necessary for a complete operating system. 2) The regeneration system shall consist of the following components: a) One(1) 100% capacity acid day tank b) Two(2) 100% capacity acid injection pumps c) One(1) 100% capacity gas scrubber d) One(1) 100% capacity caustic day tank e) Two(2) 100% capacity caustic injection pumps f) One(1) 100% capacity steam water heater g) Two(2) 50% capacity acid storage tanks h) Two(2) 50% capacity caustic storage tanks i) Two(2) 100% capacity caustic unloading & transfer pumps j) Two(2) 100% capacity acid unloading & transfer pumps k) Two(2) 100% capacity mixing tees l) One(1) 100% capacity steam trap m) Two(2) 100% capacity regeneration water pumps
6.14-25 KHABAT TPP UNITS 1&2 - VOLUME I
3). Regeneration chemicals shall be 35 percent hydrochloride acid and 45 percent caustic soda. Dilution of these chemicals to the applicable concentrations and temperatures shall be accomplished at the time of use in closed pressure systems, employing in-line mixing. 4) The cation exchanger shall be regenerated with anion at a concentration of 5 percent. Anion resin shall be regenerated with caustic at a concentration of 5 percent at max. 50 deg.C. 5) Blocking water, acid & caustic dilution water and backwash water of anion exchanger & mixed bed ion exchanger shall be demineralizer water, supplied from demi. water storage tank by regeneration water pump. Generally, rinse water shall be from demineralized water, but filtered water can be used for rinse sequentially. 6) All regenerate system valves shall be spring-to-close except leak off which shall be spring-to-open. 7) Backwash and rinse controllers shall be provided for each equipment with backwash and rinse rates indicated. Equipment shall be designed to prevent excessive rates of flow during backwashing. 8) Acid day tank shall be provided for one regeneration of cation exchanger and mixed bed ion exchanger. Caustic day tank shall be provided for one regeneration of anion exchanger and mixed bed ion exchanger. 9) The concentration of chemicals shall be adjusted by manual setting. 10) An automatic control valve shall be provided on the water side of the mixing tee with the percent concentration indicated downstream of the mixing tee. 11) Acid day tank shall be made by FRP or equal and provided with gas scrubber. This gas scrubber shall also transact poison gas of acid storage tanks. 11) Caustic day tank shall be made by 316 stainless steel or equal. 12) The steam water heater shall consist of a steam shell and tube heat exchanger with 110 percent capacity. Hot water shall be used for the caustic injection and caustic displacement steps. The heat exchanger shall be capable of heating the caustic dilution water from 0 deg.C to 50 deg.C and have the sampling connection at the low point of shell-side and provision to drain the steam condensate to 6.14-26 KHABAT TPP UNITS 1&2 - VOLUME I
the waste system or recover the condensate to the demi. water storage tank. The shell shall be constructed of carbon steel or equal and the tubes shall be constructed of type 316 stainless steel or equal. 13) Two(2) acid and two(2) caustic storage tanks shall be provided and shall have a capacity of about one month consumption included the usage of waste water treatment system. Acid storage tank shall be made of rubber lined A285 Gr.C or equal. Caustic storage tank shall be made of A285 Gr.C or equal. 14) Acid and caustic drugs supplied to waste water treatment system shall be supplied by branch lines of each injection pump outlet. C. Degasifier 1) Degasifiers shall include a flange ring at the top, which will allow the removal of a top section of the degasifier. In addition, the degasifier will include a 300 mm diameter flange port opening, ANSI 150# flange connection, with blind flange, located at the bottom of the packing section, to allow removal of the packing. Air-inlet and airoutlet connections properly sized for the maximum air flow design shall be provided. 2) The clearwell shall be integral with the degasifier section, so designed as to provide complete support of the degasifier section. The clearwell section shall also be constructed of welded steel. The degasifier with integral clearwell shall be shipped in a single piece and be self-supporting. Where the clearwell is of larger diameter than the degasifier, preference shall be given to a clearwell with dish-shaped or flat top, which will aid in supporting the degasifier. 3) Plastic tower packing of polypropylene construction or equal shall be provided. Packing shall be shipped in bags or other suitable shipping containers for field installation. 4) The clearwell drain valve shall be diaphragm type with cast iron body, rubber lined, minimum size 75 mm. 5) Each air blower capable of delivering a minimum of 0.02 cu.m/min. of air per one(1) l/min water flow. The blower shall be properly designed to overcome the static pressure in the degasifier without causing flooding and to meet guarantees. The blower shall be completely packaged and include the motor, V-belt drive with pulley 6.14-27 KHABAT TPP UNITS 1&2 - VOLUME I
and belts assembled if required, belt guard, clear-out door, drain plugs, flange inlet and outlet. The air blower shall include an adjustable outlet damper. The blower shall be shipped and assembled with suitably sized air filter and damper attached. In addition, the Bidder shall provide piping or duct work from blower to the degasifier air inlet connection. The blower shall be mounted on a steel support stand on the side of the degasifier and, if possible, shall be assembled and braced to the degasifier, and shipped in place. The blower shall be provided with inlet silencer and inlet piping. 6) The clear-well shall have a 500 mm diameter or larger bolted manhole, attached with stainless steel bolts. All clearwell nozzles shall be flange, 10.0 kg/cm2 design and the minimum number of nozzles
shall
include
pump
suction,
drain,
level
controller
connections, and high and low-level connections. 7) The degasifier inlet distributor shall be of header lateral with spray nozzle design. The inlet distributor shall be installed and suitably braced at the factory and shipped in place. 8) A perforated packing support plate or grid suitably designed to support the required packing shall be supplied. The support plate or grid shall be factory-installed, suitably braced and shipped in place. 9) The downcomer pipe from the degasifier section to the clearwell section shall end approximately 150 to 225 mm above the bottom of the clearwell. The downcomer pipe shall be factory-installed, suitably braced and shipped in place. 10) Four(4) degasified water transfer pumps shall be provided complete with motors, baseplate, coupling and mechanical seal. Pumps shall be single stage, end or top suction, horizontal type with single-row or double-row bearings. Casing shall have a cover, which shall be easily removed for cleaning and impeller removal without disturbing pipe connections or in lieu of this cover a horizontally split casing shall be provided. The pumps shall be provided with isolating valves, check valves, pressure indicators and accessories on the discharge of each pump. 11) The degasifiers with integral clearwell shall be constructed of welded steel A285 Gr.C or equal. The degasifier shell and integral 6.14-28 KHABAT TPP UNITS 1&2 - VOLUME I
clearwell section shall be completely lined internally with 4.8mm hard rubber, vulcanized in place after the tank has been hydrostatically tested. 6.14.2.5 Piping & valves A. The Bidder shall supply all piping, valves, supports, fittings and appurtenances necessary to make a completely self supporting system. FRP and PVC piping shall be supported by 1.0 m interval. B. All piping shall be ASTM A106 Grade B or A53 Grade B seamless or welded pipe with butt weld fittings unless stated otherwise. Piping of 150 mm and smaller shall be the seamless pipe, 200 mm and larger shall be the welded pipe. All flanges shall be of the ANSI 150# weld neck or slip on type. C. The Bidder shall provide interconnecting piping and fittings, which shall be of welded carbon steel. Piping with diameters of DN 65 and over shall be prefabricated in sections at shop as required for shipment. Flanges shall be provided where required for connections to vessels and valves. D. Piping and fittings connected to the demineralizer shall be lined carbon steel or equal. Rubber or Polypropylene Lining shall be used in lined pipe runs. Before lining, internal surfaces and flanges surfaces shall be blast cleaned to white metal condition in accordance with SSPC-SP5. E. Demineralizer valves size DN 50 and smaller shall be austenitic stainless steel or lined cast iron or equal. Lined cast iron valves shall be the diaphargm type with a rubber or polypropylene lining and a rubber or ethylene polypropylene copolymer(white) diaphragm. Valves over DN 50 shall be flange and lined cast iron, with lining and diaphragm. F. Piping connections DN 50 and smaller shall be the socket weld type, DN 65 and larger shall be the butt-weld type. G. All piping and fittings in contact with demineralizer water, including lines between operating valves and demineralized vessels shall conform to the materials specified in this specification. H. The Bidder shall furnish all regenerate piping. All piping immediately adjacent for both strong and dilute acid shall be made by Schedule 40 polypropylene or rubber lined carbon steel. All piping in contact with caustic shall be Schedule 40 polypropylene or rubber lined carbon steel. The waste water drain piping of each filter (exchanger) shall be PVC or equal. 6.14-29 KHABAT TPP UNITS 1&2 - VOLUME I
I. The Bidder shall furnish all lined piping and fittings for the equipment specified herein which shall be fabricated into piping spools ready for installation. The lining shall be applied by an applicator approved by the KNOC. No welding shall be done on lined pipe. The KNOC will inspect the linings. J. Plastic piping, strainers, or screens used in demineralizer internal shall be subjected to the KNOC's approval. K. The design of all items specified shall conform to OSHA design requirements. L. All piping and fitting in contact with potable water shall be fabricated of A312 type 304 in accordance with ASTM code. M. All drain valve connections shall be located at least 200 mm above the floor. N. The Bidder shall be responsible for pipe sizing and subject to approval of KNOC . O. Insulating flange kits shall be provided where carbon steel piping is connected to stainless steel piping. P. Instrument air piping shall be constructed of STS 304 seamless pipe or equal. 6.14.2.6 Pumps and accessories A. Pumps shall be designed to receive and support all forces and moments associated with startup, normal operation, and temperature changes. Duplicate pumps for the same service shall be designed to operate in parallel, at reduced flows, and without undue noise and vibration and danger of shaft breakage. B. Pump casings, motor supports, and counter flanges or bases shall be sufficiently rigid to safely withstand the forces resulting at any flow obtainable or during startup or shutdown of pumps. C. The Bidder shall list the materials which he recommends and guarantees under the specified conditions of operation and shall completely describe the proposed material by specification and analysis. D. Impellers shall be of the enclosed type, keyed to the shaft. Pump rotating assemblies shall be dynamically balanced. E. Sealing shall be standard packing gland. The glands shall be constructed to permit their inspection and packing removal without disturbing other parts of the pump. Adequate provision shall be made to collect gland 6.14-30 KHABAT TPP UNITS 1&2 - VOLUME I
leakage and drain it from the pump. The Bidder may submit, as an a alternative to standard packing glands, a mechanical seal which he recommends for the service. Seal water shall be applied to all packed pumps. F. Pump shafts shall be provided with replaceable sleeves where they pass through the stuffing boxes. The sleeves shall be hardened and adequately sealed to prevent leakage of air or liquid between shaft and sleeve. Sleeves shall be rigidly positioned. Positioning by set screws will not be acceptable. G. Pumps shall be provided with replaceable wearing rings. H. All pump and motor bearings shall be heavy duty, oil or grease lubricated. Oil lubricated bearings shall be suitable for lubrication with turbine oil. Constant level oilers shall be provided for oil lubricated bearings. I. Flanges shall be faced and drilled according to ANSI B16.5 standards. J. Pump shafts shall be accurately machined and ground and of adequate size and strength to maintain all clearances and withstand safely all stresses resulting from weight to be supported. K. Pumps shall be horizontal, radially split, frame mounted, single suction type, complete with drive motor, base plate, and all required accessories for completely operable units. L. Baseplates shall be either fabricated steel or cast iron, with drip lips and 20 mm minimum drain connections. The baseplates shall extend completely under both pumps and drivers. M. Couplings shall be spacer type, where required, to allow dismantling of the pumps without disturbing the motors or the pump pedestals. Metal coupling guards shall be provided to cover couplings and exposed keyways. N. A completely self-contained priming system shall be provided for the pumps which take suction from the underground filtered water reservoir. The priming system shall include but not be limited to foot valves, vacuum pumps, solenoid valves and a complete valving arrangement to provide pump priming as required. O. Chemical feed pumps shall be the metering, positive displacement diaphragm type and shall be furnished completely with drive motors, reduction gears, stroke control devices, and guards, all mounted on a common baseplate. 6.14-31 KHABAT TPP UNITS 1&2 - VOLUME I
P. Pump capacity shall be determined by the Bidder and shall be of adequate capacity to allow the system to perform as specified. Q. The acid and caustic unloading and transfer pumps shall have capacity to fill feed tank in 10 minutes and also to include minimum flow in addition to the feed tank filling flow. Pumps shall be suitable for chemical application. These pumps shall be started locally. However, additional stop button station shall be provided to the feed tanks to remotely stop the pumps when the feed tanks have been filled. R. The pumps for acid shall be constructed of FRP wetted parts or equal, and the pumps for caustic shall be constructed of 316 stainless steel wetted parts or equal. 6.14.2.7 Instrumentation and controls A. The instrumentation and controls of the raw water and the potable system shall designed in accordance with the section 8 of this technical specification. B. PLC based control cubicles and complete field instrumentation for the automatically controls and monitoring shall be provided. C. The control system shall be designed to enable the operator to supervise and operate the system by using LCD/keyboard. D. The control system shall be provided with the data communication interface devices with PCS for the supervisory control and monitoring in the central control room. E. Minimum two(2) operator interface station with dual LCD monitor(21” min.) and printer shall be provided. F. The PLC shall be provided with redundant (hot back-up) CPUs, power supplies and data communication networks. G. Conductivity cells and pH meters at the outlet of each anion and mixed bed exchanger shall register and alarm a preset conductance on the control panel indicating High Conductivity and Low & High pH. H. Analyzers a)
Specific Conductivity Measurement
b)
pH Measurement
c)
Silica Measurement
I. The flow totalizer shall be provided at the outlet of anion exchanger and mixed bed exchanger.
6.14-32 KHABAT TPP UNITS 1&2 - VOLUME I
6.15
Chemical Feed and Sampling System
6.15.1
Chemical feed system
6.15.1.1 System description The chemical feed system shall conform to the design and arrangement indicated on the drawings and requirements specified in the specification. The chemical feed system shall be capable of providing oxygen scavenging and pH control at the specified locations to prevent corrosion and phosphate to drum scale inhibitor. The plant shall be equipped with chemical feed systems to control the boiler and feedwater chemistry. The system shall be complete in all respects including bulk chemical storage tanks, dilution equipment, feed solution tanks, feed pumps, control systems and all pipework. Each chemical feed system shall comprise all equipment for the safe, reliable and efficient operation of the feed systems, including bunds, segregated chemical drains, appropriate ventilation and emergency eye wash and deluge shower units. Operation Capacity; The chemical feed units and related equipment specified herein shall be located indoors. The units are to be designed for mixing, storage, and feed of chemicals for oxygen scavenging, pH control and scale control of the condensate and boiler feed water for the electric power generating units as detailed in the data sheets and elsewhere in this specification.
6.15-1 KHABAT TPP UNITS 1&2 - VOLUME I
6.15.1.2
Design condition A.
Design Parameters The chemical feed system shall be designed to satisfy as follows. 1) Chemical Injection Procedure Chemical
Operation Mode
Mane
Conc.(%)
Injection Point
Method
Con. Water Boiler Initial Hydrazine
15
Pump Manual
Supply Outlet
Filling & Clean-up
Ammonia
0.2
Closed Cooling Water System
Purpose Oxygen
Revolution: Constant
Removal
Stroke: Constant
Manual pH control
2
Fresh
Auto.
Water Storage
Oxygen Removal
tank Hydrazine
2
Revolution: Constant Stroke: Constant Revolution : Proportion
Deaerator Hydrazine
Control Method
to feedwater flow Stroke: Feed-back control by deaerator outlet hydrazine
Closed Cooling Water System
Manual
Oxygen
Revolution: Constant
Removal
Stroke: Constant
Normal
Revolution: Proportion to condensate flow Ammonia
0.2
Condensate Pump Outlet
Auto.
pH
Stroke: Feed-back
Control
control by deaerator outlet specific conductivity
Phosphate
0.5
Boiler Drum
Manual
Scale Control
Manual
Deaerator Hydrazine
15
Shut Down
Fresh Water Storage
Manual
Oxygen Removel
Manual
Tank Ammonia B.
0.2
Condensate Pump Outlet
Manual
pH Control
Manual
The chemical tank shall have capacity of 2 days storage.
6.15-2 KHABAT TPP UNITS 1&2 - VOLUME I
6.15.1.3 Performance requirement The feed water entering the boiler shall be treated pH 9.3(±0.1) and dissolved oxygen shall be treated less than 7 ppb. The cooling water shall be treated pH 7.2 ~ 8.0 6.15.1.4 Design and construction features A.
General 1) The chemical feed system shall be designed so as to insure continuous, safe, and economical operation providing the maximum of reliability and without vibration or noise. 2) Duplication of components shall be maximized to the greatest extent possible such that similar components shall be interchangeable. 3) The equipment and all assembly joints or junctions shall include alignment or centering fits as required to ensure accurate reassembly or alignment of all parts. 4) The chemical feed system equipment shall be shop assembled, properly aligned and shop tested.
B.
Tanks 1) Two(2) hydrazine tank, one(1) ammonia tank and One(1) phosphate tank shall be provided by the bidder for each unit. 2) One(1) sulfuric acid tank, one(1) sodium hypochlorite storage tank, one(1) sodium hypochlorite tank and one(1) inhibitor tank shall be provided by the bidder for cooling water system. 3) All tanks shall be of welded construction of the size and arrangement as specified. The supports and skid arrangement shall be designed under the applicable code for the loads encountered during operation when filled to overflow capacity. 4) Tank shells and heads for hydrazine, phosphate and ammonia shall be not less than 3.2 mm in thickness. 5) Tank legs and skids shall be of carbon steel or equal.
6.15-3 KHABAT TPP UNITS 1&2 - VOLUME I
6) The bottom discharge of hydrazine, ammonia and phosphate tanks shall be equipped with a vortex breaker. 7) The tanks shall be constructed in accordance with API 650. C.
Metering Cylinders 1) Two(2) hydrazine and one (1) ammonia metering cylinder shall be provided by the bidder for each unit. 2) Demountable thirty(30) liter graduated metering cylinders shall be provided and fabricated as specified below. 3) Graduations should be permanently marked, in one(1) increments, with five(5) liter markings numbered.
D.
Pumps and Accessories 1) Dispensing Pumps a) The bidder shall provide one(1) hydrazine and One(1) ammonia dispensing pumps for each unit. b) Dispensing pump shall be of the air-operated, reciprocating bung type of drum pumps. c) Dispensing
pump shall be suitable for the transfer of a 35 %
solution of hydrazine shall be operated by air of 5.0 ~ 8.8 kg/㎠.g d) The lower assembly material of chemical dispensing pump shall be for type 316 stainless steel or equal. The pump shall have a stainless steel flexible hose in low-pressure. The length of hose supplied shall be suitable for the equipment arrangement and access provided by KNOC. 2) Chemical Feed Pumps a) Two(2) 100% capacity hydrazine feed pumps and two(2) 100% capacity ammonia feed pumps and two(2) 100% capacity phosphate feed pumps for each unit shall be provided by the bidder. b) Three(3) 50% capacity sulfuric acid pumps, two(2) 100% sodium hypochlorite unloading & transfer pumps, three(3) 50% capacity 6.15-4 KHABAT TPP UNITS 1&2 - VOLUME I
sodium hypochlorite pumps and three(3) 50% capacity inhibitor feed pumps for cooling water system shall be provided by the bidder. c) Pumps shall be the single-acting, positive-displacement diaphragm type and shall be furnished complete with drive motors, reduction gears, stroke and revolution-control devices, and guards, all mounted on a common base plate. d) Pumps shall be provided with an electro servo unit to permit changing the stroke with a remote signal. e) The wet parts for chemical service shall be Type 316 stainless steel or equal. Pump heads and check valves shall be replaceable and interchangeable with those within the same pressure-capacity service group, and shall be accurately machined and finished to a smooth surface with necessary drain connections provided. f) Pump frames shall be of cast iron and of rugged construction so as to support the pump chamber. All guides and seals shall be machined integral with the frame. g) Suction and discharge valves shall be replaceable and have replaceable seats, preferably without disturbing piping connections. Valves and seats shall be ASTM A 494(Hastily C) or equal. Pump connections shall be flanged to permit liquid end disassembly without disturbing piping. h) All materials such as gaskets, seals, 0-rings, etc., in contact with the pumped liquid shall be inert and free of organic materials, additives, or plasticizers. Teflon or similar fluorocarbons may be acceptable, provided the design retains the seal and does not permit material to be lost in the pumped liquid. Pump design shall ensure that no foreign material such as oil, grease, or other lubricant is in contact with the solution pumped or can come into such contact as a result of seal failure. i) Speed
reducer,
stroke
and
revolution
mechanism,
and
displacement control shall be totally oil-enclosed with means to
6.15-5 KHABAT TPP UNITS 1&2 - VOLUME I
ensure that no loss of lubricant into the pumping chamber can occur. j) Motor bearings shall be grease lubricated through suitable fittings. k) The control system shall be capable of smooth and continuous adjustment of pump feed rate through a range of 0 to 100 percent of pump capacity in response to controller output signal. l) Pump location shall provide for convenient maintenance and accessibility. m) Skid arrangement shall provide for charging any metering cylinder from a reagent drum with full view of gauge glasses on the metering cylinder. n) The bidder shall provide a relief valve of Type 316 stainless steel or equal with each proportioning pump package, and the valve shall be suitably sized to relieve at full capacity at a maximum pressure not to exceed 10 percent above the design pressure of the pump. Internal relief in a hydraulic displacement system is acceptable in lieu of external relief in the pump discharge line. o) External relief, if used, shall be piped back to the supply tank with means to observe proper reseating by a view port permitting observation of the pipe outlet. 3) Agitators and Strainers a) Each tanks specified herein shall be provided with a mixing agitator. b) All Parts in contact with the liquid, including shafts, tube, chuck and propellers shall be of type 316 stainless steel. c) The bidder shall provide a Y-type strainer of 316 stainless steel between the mixing tank and feed pump inlet. The size of inlet screen shall be at least 18 mesh, with openings not to exceed 1 mm.
6.15-6 KHABAT TPP UNITS 1&2 - VOLUME I
6.15.1.5 Instrumentation and controls A.
The Bidder shall design and supply all instrumentation and control system so as to insure accurate, safe and reliable operation under conditions of service.
B.
Instrumentation and controls shall be designed in accordance with the section 8 of this technical specification.
C.
All automatic and manual control action shall be possible through LCD monitor and PCS’s LCD monitor in main control room. And all engineering work shall be possible through the LCD monitor.
D.
The Bidder shall configure LCD graphic of the chemical feed system to the plant PCS.
E.
PLC based control cubicles and complete field instrumentation for the automatically controls and monitoring shall be provided.
F.
Minimum one(1) operator interface station with dual LCD monitor(21” min.) and printer shall be provided.
G. All hardware and software to establish the digital data communication link between the plant PCS and PLC. 6.15.2
Sampling system
6.15.2.1 General The plant shall be equipped with a system for the continuous extraction and monitoring of selected samples from the boiler steam and water circuit. The system shall be complete in all respects including sample cooling systems, analyzers, measurement devices and pipework. The selection of sample locations and analyzers shall ensure adequate observation and control of condensate, feed-water, boiler water and steam chemistry limits. The measurements from the analyzers shall be recorded on the power station PCS. A manual sampling facility shall be provided for each sample. A.
The system shall be designed with complete sample conditioning devices analyzers, transmitters, interlock, etc. The sample points and sample measuring items of each sample point are shown on the water analysis system design data and the attached drawing, water analysis system flow diagram.
B.
The water analysis system shall be designed to operate accurately and safely under the operating conditions described or implied in this 6.15-7 KHABAT TPP UNITS 1&2 - VOLUME I
specification, without undue heating, vibration, wear, corrosion or other operating troubles. C.
All piping/tubing and system components wetted by the sample stream shall be type 316 stainless steel.
D.
Each sample inlet connection shall be provided with an isolation valve suitable for the specified maximum pressure and temperature conditions for each sample.
E.
The flow stream to each measuring cell or analyzer shall include a flowmeter and a throttle valve for manual flow adjustment.
F.
The fabrication and design of the equipment to be furnished by the Bidder and the arrangement of equipment within the assemblies shall be such as to afford maximum accessibility to all parts.
G. All parts subject to high pressure or temperatures or other severe duty shall be type 316 stainless steel. H.
Parts subject to wear, corrosion or other deteriorating, or requiring adjustment, inspection or repair, shall be made accessible and capable of convenient removal when required.
I.
Rack and panel channel bases shall be provided by the Bidder.
J.
The equipment shall be completely assembled, piped and wired at the factory, ready for installation when received at the site. It shall be suitably braced to prevent distortion and damage during shipping and handling.
K.
Where a measurement signal is used for more than one device, the transmitter or other components shall be fully equipped to provide all signal requirements.
L.
The design shall permit removal from service of any indicating without upsetting the control system or requiring its readjustment.
M. The Bidder shall advise KNOC the approximate size, arrangement, weight, channel base arrangement, and access requirements of the enclosure. N.
To ensure sample freshness, each analyzer sample shall flow continuously. Bumpless transfer shall be incorporated so that the flow to the analyzer is undisturbed by grab sampling or maintenance of analyzers. 6.15-8 KHABAT TPP UNITS 1&2 - VOLUME I
6.15.2.2 Analyzers A.
Analyzers
and
associated
instruments
shall
be
designed
with
microprocessor based. The outputs shall be compatible with receiver and alarm device inputs. B.
Each analyzer shall have a self-contained digital readout meter. Each analyzer shall provide a high or low alarm status. The alarm points shall be set and indicated from the monitor's readout meter.
C.
Each analyzer shall have one(1) analog output circuits with independent zero and span adjustments. However, if a signal is required for chemical feed control system, the Bidder shall additionally one(1) analog output.
D.
Analyzer shall be suitable for flush panel mounting.
E.
Each analyzer shall be suitable to analyze the measuring range of samples as specified in attachments "water analysis system design data".
F.
The Bidder shall provide analyzers warranty service by use of local agent. This means that any problems with the analyzers can be handled locally and any malfunction resolved immediately. However, the formal warranty shall still be from the Bidder to KNOC.
G. Each analyzer shall have an independent power supply. When an analyzer is removed, there should be no power interruption to the other analyzers or devices. H.
The analyzer required reagents shall be provided with one(1) year supply of reagents.
I.
Specification and Cation Conductivity Measurement 1) Indicating analyzers for each point shall be provided for monitoring the signal output from the conductivity cell(constant: k=0.xx) assemblies. Range of measurement shall be as specified in attachments "water analysis system design data". The accuracy of measurement shall be within ±1.0% of reading. 2) The conductivity measurement shall consist of cell assemblies, indicating transmitter, cables and necessary accessories. Indicating
6.15-9 KHABAT TPP UNITS 1&2 - VOLUME I
transmitter shall be the function of password protection to secure data and access to critical setting and configuration. 3) Cation conductivity shall be measured by conductivity cell after cation columns. The Bidder's method of detecting cation column exhaustion shall be subject to approval by KNOC. Resin column, which is made transparent material, can be removed and attached easily. When the resin is exhausted, the resin column shall be refillable with regenerated resin or new resin. Being saturated with cation, the resin color shall be different from original color. 4) Conductivity
analyzer
shall
have
automatic
temperature
compensation with each kind of fluid. J.
pH Measurement 1) pH analyzer for each point shall be provided for measurement of the signal output from the pH electrode assemblies. The accuracy shall be within ±1.0% of reading. 2) pH analyzer shall include pH electrode assemblies (reference and pH electrodes), indicating transmitter, cables and necessary accessories. 3) pH analyzer shall have automatic temperature compensation, and shall have the indication of grass break and line disconnection, and shall have automatic calibration with auto-buffer recognition and sensor status.
K.
Silica Measurement 1) The silica analyzer system shall include all control valves, filters, constant head vessels, solenoid valves, manifold, sample cells, air operated valves, reagent containers and accessories required for proper operation. Unit shall be provided with one(1) year supply of reagents. The accuracy of measurement shall be with in ±5.0% of reading. 2) Zero calibration shall be performed automatically and be fully programmable auto-zeroing(blanking) capability. The measured value shall
be
compensated
implementation.
Span
for
contamination
calibration
shall
by be
analysis also
cycle
performed
6.15-10 KHABAT TPP UNITS 1&2 - VOLUME I
automatically. The Bidder shall subject automatic calibration method. Sample analysis methods shall be fully programmable reagent addition sequence with pre- and post-measurement wash capabilities. Measuring technology shall be single beam dual wavelength fiberoptic probe in the transfection mode. 3) The analyzer shall have the fully auto cleaning device for the cleaning the probe, and have programmable automatic calibration, zero point and gain, and automatic check of sample flow and reagent addition. 4)
At restart after the shutdown, the measurement cycle shall start only when the sample and the unit are at their optimum condition in order to improve the accuracy of the measured values.
5) The silica analyzer shall be capable of analyzing three(3) different sampling points, and independent output signal per each channel shall be available. Additionally while one(1) stream is analyzing, the analyzer outputs signals from the remained two(2) channels shall be maintained for continuous KNOC's PCS monitoring. L.
Dissolved Oxygen Measurement 1) Dissolved oxygen analyzer shall be provided for measurement of the signal output from the oxygen cell assembly.
The accuracy of
measurement shall be within ±5.0% of reading. 2) Dissolved oxygen analyzer shall consist of oxygen cell(316 stainless steel flow cell), indicating transmitter and necessary accessories for proper
operation.
Measurement
shall
be
made
through
electrochemical detection, using an "galvanic sensor" has a silver cathode in close contact to a pre-mounted PTFE membrane, and a lead anode that produces a fixed potential to complete the circuit. 3) Dissolved oxygen analyzer shall be equipped with calibration facility and the Bidder shall propose the calibration method. 4) The analyzer shall have the function of automatic temperature, and ambient pressure compensation, and automatic range switching, and the function of flow monitoring with alarm for flow of sample stream. 5) The Bidder shall provide the analyzer with low operational cost. 6.15-11 KHABAT TPP UNITS 1&2 - VOLUME I
M.
Hydrazine Measurement 1) Hydrazine analyzer shall be provided for measurement of the signal output from the hydrazine cell assembly. The accuracy of measurement shall be within ±5.0% of reading. 2) Hydrazine analyzer shall consist of hydrazine cell, solid state electrode, indicating transmitter and necessary accessories for proper operation. Passive diffusion reagent Addition system to condition the sample for optimal performance. Two point calibration shall be used by adding two known standards to the sample using a syringe pump. 3) Automatic calibration shall be achieved by introducing a standard known hydrazine concentration to the analyzer. The hydrazine analyzer shall automatically introduce the calibration solution, carry out any adjustments and then turn the analyzer to the sample mode. 4) Hydrazine analyzer shall have self-cleaning system with automatic temperature compensation. 5) The Bidder shall provide an analyzer that has low operational cost.
N.
Sodium Measurement 1) Sodium analyzer shall be provided for measurement of the signal output from the sodium cell assembly. The accuracy of measurement shall be within ±5.0% of reading. 2) Sodium analyzer shall be consisted of sodium cell, reagent container, indicating transmitter and necessary accessories for proper operation. Unit shall be provided with one(1) year supply of reagents. 3) The analyzer shall have the function of calibration by introducing double known standard the ppb range. 4) Sodium analyzer shall have the function of auto range change ( 0～1/ 1～10 ppb) and automatic temperature compensation automatic sample and pH conditioning with no pumps and have detection limit for sodium ion concentrations 0.01ppb.
6.15-12 KHABAT TPP UNITS 1&2 - VOLUME I
5) Sodium analyzer shall have flow cell with air stirring and sample air transport. Also, Sodium analyzer shall have the function of Self diagnostics. 6.15.2.3 Sample conditioning rack, analyzer panel, and control panel A.
The water analysis system shall consist of three sections as sample conditioning rack, analyzer panel and control cabinet taking into account improved functions and easy maintenance.
B.
The sample conditioning systems shall maintain samples within the following tolerances of the desired values using cooling water at 35 deg.C maximum and approximately 5.9 kg/cm2g operating, 10 kg/cm2g maximum.
C.
Sample flow to each cell or analyzer ± 2 percent.
D.
Sample temperature to each cell or analyzer 25 ± 1 deg.C.
E.
Under all sampling conditions, cells or analyzers not requiring minimum sample flow rate shall be designed with a flow rate of approximately 50～100 cc/min. If the analytical equipment requires some range of flow rate, the analyzer minimum flow shall be the design basis.
F.
Plant cooling water about 35 deg.C maximum and approximately 5.9 kg/cm2.g operating, 10 kg/cm2g maximum will be supplied to sample conditioning rack where required. The required coolant flow of the cooler in cubic meters per hour shall be stated by the Bidder.
G. Sample condition indicators shall be provided as the following. 1) A thermometer, flow meter and pressure gage in each sample line downstream of the secondary cooling system. 2) A flow meter in the sample line to each measuring cell and analyzer. The flow meter range shall be suitably coordinated with the flow requirements of the cell or analyzer. H.
Rack and panels shall be completely fabricated by the Bidder, including equipment mounting with properly designed supports and complete factory installed internal piping, tubing and electrical wiring for all devices.
6.15-13 KHABAT TPP UNITS 1&2 - VOLUME I
Internal piping, tubing, wiring and connections shall be securely fastened, compactly arranged and readily accessible. I.
Rack and panel shall be furnished with vibration dampeners, for isolation of the panel from vibration transmitted through the supporting floor. Type of the dampeners shall be subject to KNOC approval.
J.
The Bidder shall provide a water baffle between the sample conditioning rack, analyzer panel and control panel to prevent damage to analytical and transmitting instruments in the event of a high pressure tubing rupture.
K.
All required pressure, temperature and flow indicators, and the handle of isolation valves shall be mounted to permit viewing or manipulation from the front of the panel.
L.
Sample Conditioning Rack 1) The sample conditioning rack shall be totally enclosed with rear doors. The rack shall consist of sample lines. The size of sampling conditioning rack shall be enough to maintenance and repair. 2) A typical line shall be consist of the following items, but not be limited to; - Interface connection - Manual isolation valve - Primary cooler with cooling water throttling valve - Automatic controlled sample inlet and blowdown valve - Pressure reducing valve - Sample filter - Pressure relief valve downstream of the pressure reducing valve - Secondary cooling system - Pressure and temperature indicators - Automatic pressure control device (where required) - Grab sample valve - Routing to the sink 3) A manual isolation valve(immediately downstream the interface point) shall allow the operator to isolate the line for maintenance and repair. Double isolation valves shall be provided at high pressure sample lines as shown on attached reference drawing. 6.15-14 KHABAT TPP UNITS 1&2 - VOLUME I
4) Sample temperature control Sample temperature shall be reduced using 'primary' full counterflow sample coolers to achieve close approach temperature of the primary cooling water. Secondary "trim" coolers shall be used and cooled by a closed chilled water system, to achieve a controlled temperature of 25+1 deg.C. All coolers shall be furnished as an integral part of the conditioning rack. The temperature control system shall be furnished to maintain automatically the temperature of all samples (including manual samples) at 25+1 deg.C. Sample temperature shall be controlled by controlling the temperature of the cooling water supply to final temperature control sample "trim" coolers with chiller units. The cooling water shall be circulated between the sample coolers and chiller unit in a closed loop, with temperature automatically controlled by controlling refrigerant flow to the compressor in the chiller unit. The temperature control system shall include all necessary accessories; including the sample coolers, full-capacity circulation pump for the cooling water, full-capacity hermetically sealed compressor, and all necessary piping, valves and controls. A control valve to regulate the refrigerant cooling water supply to the chiller unit shall be furnished.
The chiller unit for each unit service shall be
mounted outside the panel in an adjacent area. The Bidder shall establish the chiller loads and include 50% over capacity, submit the calculation sheet after award. Where required, primary sample coolers shall be installed upstream of the temperature control coolers, to provide the initial sample cooling,
bringing the temperature within a range at which it can be
satisfactorily controlled with the trim cooler. All coolers shall be of the shell and tube type design, with counter current flow of sample and cooling water. All coolers shall be arranged side by side on a rack and shall be connected to an inlet and an outlet cooling water header, without disturbing the sample connections and other cooler for rapid removal and replacement of tube. The primary sample coolers shall be equipped with a inlet globe valve and outlet check valve, and secondary sample cooler shall be 6.15-15 KHABAT TPP UNITS 1&2 - VOLUME I
equipped with a inlet and outlet globe valve for throttling the supply of cooling water. The sample coolers shall have removable shells. All coolers shall have 316 stainless steel tubing. All shells shall be 304 stainless steel. Temperature indicators shall be provided to measure and indicate each trim sample temperature. Temperature measurements shall be taken downstream of each trim cooling device. 5) Two air pneumatic shutoff valves shall be provided for each line. The first valve shall be for sample inlet and the second valve shall be for blowdown. These valves shall be controlled both manually and automatically from the control panel. 6) Automatic pressure reducing devices shall be provided in order to automatically control the required pressure and flow to account for the sample line pressure variation during plant load cycling such as boiler feed pump outlet, economizer inlet and main steam. 7) Primary filters shall be provided and installed upstream of pressure reducing valves, and shall be placed with easy access in the sample conditioning rack. These filters shall be capable of protecting the devices of the filter downstream from contamination. 8) Each analyzer incoming sample except that for grab sample shall be filtered before analyzer.
Pore size shall be between 10 and 300
microns. 9) Pressure control valves with pressure controllers or pressure reducing valves shall be provided to maintain sample pressure specified by the analyzer manufacturer. 10) Each sampling line except hotwell sample line shall be provided with a pressure relief valve downstream of the pressure reducing valve, to protect the associated measuring cells and/or analyzers from overpressure in accordance with pressure limitations imposed by the manufacturer. 11) The conditioning rack shall be a free standing rack, into which all conditioning equipment is mounted. The sample shall be connected to the rack at the top rear side. From this point, the sample shall 6.15-16 KHABAT TPP UNITS 1&2 - VOLUME I
flow through tubing and various control instruments to be conditioned its pressure, temperature, and flow rate. 12) Grab sample facility shall be designed to exhaust sampling water through the common sink and equiped with manual valve individually. 13) The sample conditioning rack shall have a 304 stainless steel waste header extending the length of the rack for collection of all wastes. 14) The sample drain headers shall extend the entire length of the rack and shall be provided with connections for all installed analyzers. 15) The rack shall have a 316 stainless steel used sample header which shall extend the length of the sample rack and have a sufficient number of openings on the top of the header to accommodate all used samples to be reclaimed together for disposal. 16) The Bidder shall provide the differential pressure switch between coolant supply and return line. The switch shall be used for the monitoring of loss of primary coolant. M. Analyzer Panel 1) The analyzer panel shall be designed to be located in close proximity to the sample conditioning rack. The analyzer panel shall be totally enclosed with rear doors. 2) It shall be a free standing panel into which analyzers are mounted. 3) If stand alone type analyzer will be provided, they shall be installed next to the sample conditioning rack. 4) The drain lines from the analyzers shall be directed such that whenever the sample inlet valve closes, cells /probes shall be kept wet until the flow restores. N.
Control Panel and Programmable Logic Controller 1) The control cabinet shall be NEMA 12 enclosure type for protection against dust and water. 2) The system shall have alarms for the following condition as a minimum.
6.15-17 KHABAT TPP UNITS 1&2 - VOLUME I
- Each analysis result abnormal - Condensate hotwell sample pump discharge press. low - Condensate hotwell sample pump trip - Chilled water circulating pump trip - Chilled water temperature high - Control system trouble & power failure - Logic discrepancy - Others (after award) 3) The sampling 4～20mA signals shall be transmitted to chemical feed control system from water analysis control system by hardwire 6.15.2.4
Sample pump A.
The Bidder shall supply one pump per skid, four skids per unit.
B.
Sample pump skid shall include the suction, discharge and return valves, check valve, discharge pressure gages and switches, and differential pressure gages and switches.
C.
The pumps shall be the horizontal, centrifugal canned type with all specified and required accessories for operable units. 1) The pumps shall be designed and manufactured to avoid pump cavitation .
D.
The Bidder shall state the maximum limits of vibration and the method of measurement that will be used to determine correct operation of the pump and coupling before shipment.
6.15-18 KHABAT TPP UNITS 1&2 - VOLUME I
6.16
Auxiliary Boiler
6.16.1
General A.
The auxiliary boiler shall be natural circulation and shall be composed of a drum type, including all pressure parts, refractory, insulation, casing, supporting steel base, usual accessories, trim and soot blowers.
B.
The furnace shall be fired by air and light oil incorporating air inlet damper, forced draft fan with motor, discharge ductwork, inniter system, burner assembly, flue gas outlet breeching, outlet damper, duct and stacks.
6.16.2
Design and construction The boiler shall be designed throughout so as to ensure continuous, safe and economical operating providing max. of reliability and without undue heating, vibration and noise. The boiler, auxiliaries and accessories shall be designed in accordance with the applicable parts of the listed codes and standards. The boiler proper shall be shop assembled as complete as possible and shipped as a single section so that only the forced draft fan with electric motor drive, sir ducts, gas duct and breechings, piping, and miscellaneous trim and control devices will require attachment during installation. Auxiliaries Doiler and accessories shall be designed for the seismic factor and winding loading in this specification..
6.16.2.1 Furnace and casing The furnace shall be adequately sized to prevent overheating in any portion of the boiler when operating continuously throughout any load and condition. The furnace walls, floor, and roof shall be cooled with water tubes, however, a portion of the front wall at the burners may be protected from overheating by an adequate amount of refractory material. The distance from the centerline of the burners to the wall, roof, and internal tubes shall be sufficient to prevent any flame impingement on the tubes throughtout any load and condition. The boiler casing shall be reinforced for pressurized operation and shall be designed to prevent gas leakage. The furnace, fans, flues, ducts, piping, and appurtenances provided by the Bidder shall be thermally insulated so that the outside surface temperature wiil not exceed the ambient air temperature by
6.16-1 KHABAT TPP UNITS 1&2 - VOLUME I
more than twenty(30) degree C when operating with ambient air velocity of 1 meter per sec. The flue gas outlet transition section shall be flanged with an expansion joint for connection to the ductwork or stack. Necessary observation ports and access doors shall be provided as required for operation, inspection and maintenance. 6.16.2.2 Pressure parts Pressure parts for the boiler shall be designed and fabricated from materials with analysis and thickness that meet the requirements of the ASME Boiler and Pressure Vessel Code, Section I. The longitudinal and circumferential welds of the drum and header shall be fully radiographed and stress relieved in accordance with the applicable code and standard, and magnetic particle test shall be examined on the welds after stress relieved. Nozzle shall be forged steel and welded to the drums and headers. The steam drum shall be equipped with multistage internals for steam drying and with provisions for feedwater distribution. Tubes shall enter steam drum radially and below the normal water level. Bends shall be such that the tubes can be cleaned internally with a commercially available mechanical tube cleaner. Tube shall be expanded at drum connections without over-rolling. 6.16.2.3 Trim Boiler trim shall be include all ASME Boiler and Pressure Vessel Codes, Section I items and at least the components listed in the following subparagraphs : A.
Drum and superheater outlet safety valves, including gages and drip pan discharge elbows and exhaust stack.
B.
Electric motor-operated main steam outlet stop valve and check valve, and piping up to main steam steal line terminal point, which may be attached in the field if necessary.
C.
The stop valves of feed water shall be furnished with an electric motor operated sized to hold the valve tightly closed during hydrostatic testing of the feedwater piping system.
D.
The feedwater regulating valves shall be provided with two isolating block valves, a bypass globe valve and all piping. The main steam backpressure control valve shall be provided with all necessary modulating 6.16-2 KHABAT TPP UNITS 1&2 - VOLUME I
type pneumatic controls to ensure that boiler outlet pressure does not fall below a predetermined point. A 25mm bypass valve shall be included with the electric motor-operated main steam outlet stop valve for warmup purpose. E.
Light oil control and trip valves shall include piping from the trip valve to the burners.
F.
Water column with gage glass and level transmitter for high-low level alarm and low-low level fuel trip switches shall be provided and shall be piped to the boiler drum with the isolating valves.
G. Drum level indicator located at eye level at grade shall be provided including a constant head chamber, compatible secondary electronic indicator, and all required shutoff valves and manifolds. H.
Drum steam pressure gage shall be provided with 150mm dial, range (050kg/cm2g), minimum scale range (0.1kg/cm2g), accuracy (± 1.0%), piped with valves for observation at grade.
I.
Self-contained, controlled, steam sootblower system shall be provided by the Bidder.
J.
Continuous bloedown valve located at grade operating level.
K.
Dual lower drum bloeoff valves and piping shall be provided up to terminal point.
L.
Acid cleaning connections shall be provided as required for cleaning the pressure parts and to facilitate flushing and drainage.
M. All drain and vent pipings with valves shall be provided as required. N.
Nozzles with double valves shall be provided for all vents, drains, instrumentation and controls, chemical feed, and sampling connections.
O. Heating steam to the lower drum heating coils will be obtained fron the auxiliary steam system. The steam coils should be large enough to maintain adequate boiler pressure. All piping, valves, steam traps, etc. should also be sized on the above basis. P.
Deaerator pegging steam control valve(s) shall be supplied to control deaerator pressure over the opearting range. The pegging steam shall be derived from the auxiliary boiler steam header. Deaerator makeup shall be controlled by a deaerator makeup control valve supplied by the Bidder. Deaerator storagr tank level shall be controlled by a level control valve suplied by the Bidder.
6.16-3 KHABAT TPP UNITS 1&2 - VOLUME I
6.16.2.4 Forced draft fan The forced draft fan shall have a max. speed of 1,500 rpm and shall be direct motor driven. The fan shall have test block margins of site condition for temperature, 30% for static pressure and 20% (by weight) for capacity. Vane-type inlet dampers shall be furnished with the fan, together with a discharge duct and supports to the boiler windbox. 6.16.2.5 Burners and windbox The burner(s) shall be of a size and quantity to meet the boiler performance requirements. The boiler shall supply all steam necessary for the operation of its burner(s). The connecting piping shall be complete with all valves, traps and strainers. The burner(s) shall be compatible with the control system. The windbox shall be manufactured of steel plate at least 6mm thick and shall be designed to provide uniform air entrance into the burner registers. The windbox shall be seal welded to the boiler front plate. The light oil burner(s) shall be of the air-atomizing type for start-up and steam atomizing after sufficient steam pressure is generated. The switchover shall be done manually at the burner front in cold start-up and automatically in hot start-up. An oil gun shall be designed to fit into a burner socket and shall be clamped securely in place but manually retractable for cleaning. The burner shall incorporate a device to permit the oil passages of the gun to be purged with steam or air after use so that the gun may be removed without dripping oil. All burner-front accessories, such as flexible hoses, supervisory cocks with limit switches, gun engagement switches, fuel and atomizing media gages, atomizing media pressure control valves, and drain traps, shall be provided in accordance with the required codes. 6.16.2.6 Sootblower The unit shall be provided with a motor driven soot blowing system. Sootblower elements shall be suitable for continuous extra high temperature exposure to the products of combustion. Each element shall include its shut-off valve including steam trap with block and bypass valves for complete cycle operation and the following appurtenant items : A.
Integral motor starters with NEMA 12 enclosures for rotary sootblowers and long retractable sootblowers.
6.16-4 KHABAT TPP UNITS 1&2 - VOLUME I
6.16.2.7 Stack The stack shall be self supporting type. The stack shall be of welded steel construction and limited to ensure satisfactory operation throughout the full expected life of the station. All structural steel and plate material shall be ASTM specification A36 or equivalent. All welding shall produce full penetration, gas-tight joints and be in strict compliance with AWS code D1.1 structural welding code. A stack shall be equipped with drains and an inspection manhole. Stack shall be located at grade. The Bidder provide breeching, including a sealed flexible joint and breeching supports, between the casing and the stack. All surfaces of the breeching and all surfaces of the stack to a height of 2.0m above grade or to the top of the breeching, whichever is higher, shall be insulated by the Bidder. Lighting for stack shall be provided, if required. The Bidder shall furnish necessary instrumentation for measuring the contents of oxygen and combustible in the flue gas, which shall be recorded, indicated at the Bidder’s control system. 6.16.2.8 Blowing system One continuous blowdown system shall be supplied for the steam drum. The maximum blowdown rate shall be 3% of the feedwater flowrate at MCR. The blowdown system shall include, but not be limited to, the following. A.
One manual-operated isolation valve, normally locked in the open position.
B.
All blowdown piping to the blowdown tank.
C.
All necessary hangers and supports.
D.
Blowdown valves and piping shall be suitable for passage of acid wash and shall be of design.
E.
Blowdown tank shall be designed, fabricated and inspected in accordance with the ASME Boiler and Pressure Vessel Code, Section VIII, Division I.
F.
Blowdown tank shall be arranged for venting to atmosphere.
6.16.2.9 Combustion and feedwater controls A.
Automatic modulating combustion and feedwater controls of the microprocessor based control system shall be furnished. The control system shall be designed fo automatic and manual operation from the 6.16-5 KHABAT TPP UNITS 1&2 - VOLUME I
operator interface station with bumpless, transfer from one to the other. The electronic and pneumatic controls shall be designed to prevent resetwindup. It shall not be necessary to place any of the control stations in manual mode during periods of normal firing condition, but shall be necessary to operate in manual mode partially during period of low firing or hot standby(boiler shut-down) to prevent reset windup. All instruments and controls for operating the boiler, auxiliary pumps and other associated items in the auxiliary steam generating system shall be located near the auxiliary boiler. It shall be a freestanding item entirely separate from the boiler. B.
Master steam pressure control system shall be provided to maintain steam pressure by proper regulation of fuel and air flows. The control system shall be operate the boiler with a minimum of excess air maintaining steam pressure within ±3 percent of set pressure.
C.
The combustion control system shall include fuel and air flow controls, fuel-to-air ratio adjustments, and fuel and air cross limit controls to ensure a safe-to-air ratio over the entire operating range. The system shall also include the fuel regulator, air flow damper actuator, transmitters, and square root extractors, to form a complete, safe, and dependable control system. Afuel supply pressure regulator shall be provided to maintain constant pressure ahead of the Bidder’s fuel control valve. The fuel flow transmitter shall be designed to assure dependable metareing over the required range of flows and shall be complete with the necessary primary flow element. Aminimum firing rate limit shall be provided to prevent operation of the burner at rates below the minimum required for stable burner performance.
D.
The minimum firing rate limit shall consist of a minimum burner pressure limit. The fuel control valve shall be selected to operate within the maximum and minimum usable Cv listed by the manufacturer. If sufficient range ability cannot be attained with one valve, two fuel conatol valves of different sizes shall be provided in parallel and arranged for sequential operation with overlap.
E.
The Bidder shall provide a three-element, feedwater control system with transmitter and all other necessary devices to form a complete and dependable control system. The feedwater and steam flow transmitters shall be supplied complete with required primary flow elements. 6.16-6 KHABAT TPP UNITS 1&2 - VOLUME I
F.
The deaerator control system shall consist of three major elements ; • Deaerator pressure control • Deaerator condensate make-up control • Deaerator level control The source for pressurizing the deaerator shall be auxiliary steam. Control shall be provided to modulate the pressure control valve(s) over the entire operating range. Split range control shall be used if required. Feedwater demand shall be used as a feed forward index for deaerator level. Suitable interlocks shall be provided to prevent high water level damage to the deaerator during rapid bad changes or boiler trip conditions. Deaerator level control shall be modulated by the deaerator level control valve.
6.16.2.10 Burner safety controls In addition to the safety features included in the combustion control system, the Bidder shall provide an automatic programmable logic controller(PLC) type’s burner ignition, and operational safeguard system in accordance with NFPA standards. The safeguard system shall consist basically of the controls and interlocks required to produce a safe firing and tripping sequence and a series of devices and interlocks to trip the boiler during any of a number of specified unsafe operating conditions. Station operating personnel shall start and/or determine that the necessary auxiliaries are in service before starting the boiler with a push button on the local control panel. Permissive conditions shall be determined by Bidder. 6.16.2.11 Pumps The auxiliary boiler feedwater pumps, condensate make-up pumps shall be horizontal centrifugal pumps with electric motor drivers and light oil feed pumps shall be screw pumps provided with electric motor drivers and baseplates. A.
Auxiliary boiler feedwater pumps The Bidder shall furnished two(2) 100 percent capacity as an integral part feed water pumps of the auxiliary boiler package. The pumps shall include at least 4 percent surge and 4 percent wear allowance. The suction of each pump shall be provided with an isolation valve, strainer and pressure gauge. The pump discharge with isolation and check valve and pressure gauge shall be provided. Minimum flow and 6.16-7 KHABAT TPP UNITS 1&2 - VOLUME I
recirculation lines with control devices and isolation valves piped to the deaerator storage tank shall be provided. Each pump and its driver shall be mounted and line up on a grid fabricated steel, drip-rim, common base plate of adequate size. Pumps shall be mounted below the deaerator and shall operate within their NPSH requirements for all conditions of operation. Each base plate shall be large enough to preclude equipment overhang. Pump material and construction shall be suitable for the specified service. Materials or parts where close running clearances will be encountered shall be selected for their resistance to galling. Shaft sleeves are required and shall be of suitable heat treated or hard faced material, ground and polished and so arranged that that will not turn on the shaft. The sleeves shall have an adequate seal to prevent leakage of air or water between the shaft and the sleeve. The general design and arrangement of all working pumps parts shall provide ready access for inspection, renewable and repair of parts and lubrication. All passages of the pumps shall be designed to permit complete drainage with the pumps in the normal operating position. The pumps shall be designed to be free of crevices and to prevent accumulations of particulate matter. Connections shall be provided for vents, drains and pressure gauges. Attachments for lifting and handling shall be provided. Pump casing shall be designed to withstand the hydro test pressure as well as pump shutoff head at rated speed. The impellers and shafts completely assembled shall be statically and dynamically balanced before incorporation into the pump. They shall be designed with critical speeds substantially away from operating speed. Oil lubricated ball bearing shall be furnished to provided smooth operation and absorb any unbalanced forces during all service conditions. Pump seals shall be of the mechanical seal type. Pumps shall have provisions for collecting seal leakage so it may be routed to sumps. Seal design on all pumps shall preclude introduction of bearing oil in the feedwater. Forged steel, flexible shaft coupling shall be furnished for each pump6.16-8 KHABAT TPP UNITS 1&2 - VOLUME I
motor connection. Coupled pumps shall be provided with coupling guards. Keys of keyholes shall not extend beyond the coupling guard. All necessary controls and instrumentation such as selector switches, pressure switches to activate the standby pump, etc., to meet the pump design conditions shall be provided. B.
Condensate make-up pumps The Bidder shall furnished two(2) 100 percent capacity condensate make-up pump as an integral part of the auxiliary boiler package. The pumps shall operate within their NPSH requirements for all conditions of operation.
Minimum flow and recirculation lines with orifices,
isolation valves and check valves piped to the condensate storage tank shall be provided. Pump seals shall be of the gland seal type. C.
Light oil feed pumps The Bidder shall supply furnished two(2) 100 percent capacity light oil feed pumps as an integral part of the auxiliary boiler package. The baseplates shall be of fabricated steel or cast iron with drain rim and drain connections. The surface of the baseplates shall extend under both the pump and the drive motor, and shall be fitted with all necessary mounting pads, anchor bolts and grout holes. Suction and discharge connections may be flanged as required for the specified service. Flanges of cast steel shall be raised face, face and drilled in accordance with ANSI ASME B16.5. Bearings may be of the sleeve or anti-friction type in accordance with the manufacturer’s standard design. Shafts shall be accurately machined from hardened carbon steel and of adequate size and strength to maintain all clearances and withstand safety all stresses resulting from full voltage starting and normal operation. Pumps shall be furnished with mechanical seals. Drip chambers shall be so constructed to ensure effective collection of all drips. Pumps shall be direct coupled to the drive motor by a flexible coupling of suitable size to transmit the require torque continuously and the satisfactorily and to handle any misalignment that may occur under normal conditions. Pump material and construction shall be suitable for the specified service. Materials or parts where close running clearances will 6.16-9 KHABAT TPP UNITS 1&2 - VOLUME I
encountered shall be selected for their resistance to galling. All necessary controls and instrumentation such as selector switches, pressure switches to activate the standby pump, etc., to meet the pump design conditions shall be provided. 6.16.2.12 Deaerator and storage tank The deaerator shall be of spray and tray type. The deaerator shall be designed, fabricated, examined, and constructed in accordance with the ASME Code, Section VIII, Devision I. The deaerator shall be designed quietness of operation and minimum vibration at all rates up to and including its maximum capacity, during rapid load changes, and with entering feedwater temperature. The deaerator and its component parts shall be designed so that safe working stresses are not exceeded during any mode of operation. Design and fabrication of structural steel shall be in accordance with the applicable Codes and Standards. Deaerator storage capacity shall be at least 5 minutes without influent flow at rated output. Over the entire load range, the free carbon dioxide content shall be reduced to zero, and the deaerated water shall be heated to the saturation temperature corresponding to the steam pressure maintained in the shell. Distribution pipes and other welded internal heater trays, impingement plates and nonwelded internal trim shall be made of ASTM A240 type 304 stainless steel. All internals trim shall be made of ASTM A240 type 304 stainless steel and shall be fastened in place so that they cannot shake loose. The storage tank shall be horizontal and an integral part of the deaerating section. Adequate access shall be provided for inspection and maintenance of the deaerator internals. Pressure vessels shall be of all welded construction. The storage tank shall be provided with a drain connection, located flush with the bottom of the tank. The deaerator shall be provided with an internal stainless steel vent condenser, including vent deflector-hood, vent orifice or a separate vent valve. Downcomers shall be equipped with deflector hoods to protect the tray from upsurges of condensate. Steam inlet impingement baffles shall be designed to withstand an occasional water slug. Nozzle shall be extend beyond the insulation 6.16-10 KHABAT TPP UNITS 1&2 - VOLUME I
thickness. The auxiliary boiler feedwater connection shall extend 75mm up from the bottom of the storage tank. Pipe manifolds shall be furnished for all inlets and outlets requiring multiple connections to the deaerator, including the manifolds for the level instruments. 6.16.2.13 Chemical feed tanks and pumps A complete system shall be provided for mixing, storing and metering phosphate, hydrazine and ammonia solutions into the auxiliary boiler drum and feedwater for the prevention of corrosion and scaling. The phosphate tank and metering assembly shall consist of one tank with cover and two metering pumps. The phosphate tank shall be provided with a motor driven portable mixer, mixing basket and gauge glasses. The hydrazine and ammonium hydroxide tank and metering assemblies shall consist of one tank with cover and two metering pumps. The tanks shall be provided with motor driven portable mixers and gauge glasses. 6.16.2.14 Instrumentation and control A. The Bidder shall furnish a complete package of instrumentation and controls necessary to meet the requirements of this specification, and that shall offer a high degree of reliability and safety to both personnel and apparatus. B. Instrumentation and controls shall be designed in accordance with the section 8 of this technical specification. C. PLC based control cubicles and complete field instrumentation for the automatically controls and monitoring shall be provided. D. Minimum one(1) operator interface station with dual LCD monitors(21” min.) and printer shall be provided. E. All instruments and controls shall be easily accessible for maintenance and adjustment. Cubicles and equipment therein shall be suitable for operation in the ambient condition at their locations. Internal fluorescent illumination with switch, fan, space heater and power receptacles shall be mounted in each cubicle. F. The control system shall be designed to enable the operator to supervise and operate the system by using LCD/keyboard in local and OWS in CCR. 6.16-11 KHABAT TPP UNITS 1&2 - VOLUME I
G. The control system shall be provided with the data communication interface devices with PCS for the supervisory control and monitoring in the central control room.
6.16-12 KHABAT TPP UNITS 1&2 - VOLUME I
6.17
Diesel Generators
6.17.1
General The specification for four(4) set of black start & emergency diesel generator system for Irag Kurd Project complete with accessories are descriptive of the requirements but do not attempt to enumerate all details of accessories and appurtenances. Such details are to be provided by the Bidder after award.
6.17.2
System description
6.17.2.1 Each diesel generator shall be a direct injection, compression ignition, turbocharged and charge air cooled industrial engine of standard design and construction in accordance with the requirements of ISO 8528. 6.17.2.2 The engine flywheel shall be suitable for the required starting duty. 6.17.2.3 Turbochargers shall be exhaust gas driven. 6.17.2.4 Engine governors shall be in accordance with ISO 8528 Performance Class G1. Each diesel generator shall be complete with a local control panel which shall be interfaced to the electrical control system. 6.17.2.5 The fuel shall be derived from the main fuel oil system. 6.17.2.6 One cooling radiator shall be provided for the engine taking into account the engine duty. 6.17.2.7One heat exchanger shall be provided for cooling the engine jacket water. The jacket water system shall be thermostatically controlled, with an engine driven circulating pump. 6.17.2.8 The lubricating oil system shall be self contained independent pressurized serving all the engine requirements. 6.17.2.9Engines started using compressed air shall have one receiver per engine, and the system shall be sized for six starts. 6.17.2.10
It shall be possible to exercise each diesel generator on load for test purposes. When exercising all engine protection, alarms and trips shall be operational. During exercising the load on the essential supplies/common switchboard shall be transferred to the diesel generator.
6.17.2.11
Each generator shall be of the brushless type with Class 155 (F) insulation with temperature rises and total temperatures limited to Class 130 (B) limits. 6.17-1 KHABAT TPP UNITS 1&2 - VOLUME I
6.17.3
Operation condition
6.17.3.1 The power station shall be equipped with diesel engines generating plant with the purpose to perform both black-start of a unit and to feed emergency loads during an emergency shutdown. 6.17.3.2 It shall be composed by four diesel generators. Their size shall be selected in order to allow the following action : -
Three diesel generating units must be able to perform the black start of a plant unit and feed emergency common loads.
-
Two diesel generating units must be able to feed emergency loads of two plant unit and emergency common loads.
-
Each diesel generating unit must be able to feed emergency load of one plant unit and emergency common loads.
6.17.3.3 Each diesel generating set shall be equipped with its own step-up transformer, circuit breakers, protection, measuring and control panel. 6.17.3.4 The characteristics of the generator will be as follows : - Design load(preliminary)
[1250] kVA
- Design voltage
400 V or 6 kV
- Design frequency
50 Hz
- Design power factor
0.85
6.17.3.5 Start-up,
shut-down
and
paralleling
operations
shall
be
performed
automatically by means of a local PLC providing the diesel engine control. 6.17.3.6 Alarms and instrumemtation will be connected to terminals for remote monitoring. 6.17.4
Mechanical design requirements
6.17.4.1 The diesel engine shall be of the multi-cylinder, in-line or V-type, water cooled, cold starting type, fuel diesel, four stroke cycle, stationary type and of the ISO and IEC 60034-22 standard design for emergency source of power required for power plant service. 6.17.4.2 The power rating of the engine shall be stated by the Bidder for each rated output of the unit. The site continuous rating shall be based on unlimited engine operating hour and not less than 2,000
engine operating hour
between maintenance overhauls.
6.17-2 KHABAT TPP UNITS 1&2 - VOLUME I
6.17.4.3 The engine shall be manufacturer's current design for stationary service. The engine shall be directly connected to the generator. The rated speed of the engine shall not exceed that of the manufacturer's engines of the same configuration already in operation for a period of 3 years either base load or emergency electrical power generation. Tandem or twin units driving a common generator are not acceptable. 6.17.4.4 The basic engine accessories shall include : a) Engine piping, including inlet and outlet connections as required for jacket water, lubricating oil, fuel, starting air and exhaust, including all counter flanges. b) Lubricating oil sump including level dip stick indicator for level observation c) Electric load, speed-sensing and woodward type or equivalent governors including control box, resistor box, and potentiometer. The governor shall have capability for both independent and parallel operation. Load sharing is not required. The governor supplied shall comply with ISO 3046. Frequency drop for independent operation shall not exceed 5％. d) Overspeed trip device at 115 percent of the rated speed. e) Flywheel turning device. f)
Turbochargers exhaust gas driven type.
g) Relief valve for cylinder and/or crankcase. 6.17.4.5
The air intake system shall include : a) Dry type intake filter. b) Finned tube or plated fin air cooler.
6.17.4.6
The exhaust gas/air system shall include : a) Silencer, reactive type. b) Expansion joint, stainless steel bellows with carbon steel flanges.
6.17.4.7
The fuel oil system shall include: a) Heavy duty filters with fine mesh, duplex, replaceable element type, inlet and outlet differential pressure indicator gauge, differential pressure switch for annunciation. b) The fuel storage capability of day tank designed for 4 hours continuous operation with high and low level switches for annunciation and level gauge, suitable supporting structure for placing on foundations.
6.17-3 KHABAT TPP UNITS 1&2 - VOLUME I
c) Control provisions(dry contacts) for starting and stopping the fuel oil transfer pump by high and low level of fuel oil day tank. d) Solenoid valve for fuel inlet 6.17.4.8
The lubricating oil system shall include : a) Cooler, radiator driven AC motor. b) Duplex full-flow lube oil filter metal edge type, or basket type with fine mesh, inlet and outlet differential pressure indicator gauge and differential pressure switch for annunciation. c) Warm lube oil circulating and prelubrication pump, motor driven, with mechanical seal, baseplate, and flexible coupling with guard. d) Lube oil temperature indicators on inlet and outlet of lube oil cooler. e) Main lube oil pump, integral with engine. f)
Priming lube oil pump including one(1) stand-by pump.
g) Lube oil preheater. h) Potable electric lebe oil pump for filling. 6.17.4.9
Cooling system shall include : a) Engine-driven jacket water circulating pump. b) Air-cooled radiator with shroud and mounting devices. c) AC Motor driven radiator fan. d) Expansion tank with level indicator and level switch for low level alarm, air vent and float valve. e) Jacket water heater with thermostatic control to maintain minimum jacket water temperature when engine is not in operation. f)
All instruments, controls, etc. necessary to maintain the required minimum and maximum water temperatures for each component.
6.17.4.10 Starting equipment shall include : Suitable starting equipment shall be supplied. The equipment shall be of the compressed air and rated for three start attempts in succession followed by one successful start. a) Compressed air system shall include that one(1) air receiver tank sized to start engine a minimum of four(4) times without recharge, with pressure gauge, safety valve, and automatic drain, which shall be designed in accordance with ASME Section Ⅷ. One(1) air compressor multi-staged, air cooled type, having capacity to 6.17-4 KHABAT TPP UNITS 1&2 - VOLUME I
charge air receiver from minimum pressure to maximum pressure within thirty(30) minutes. Start and stop of air compressor shall be controlled automatically by pressure switch fitted at air receiver. b) In case of the initial starting for black start & emergency diesel generator sets under black out, the Bidder shall provide small capacity of generator set with cell motor starting device using battery remotely for supply electric power of lube oil priming pump and air compressor. c) Air compressor including one(1) stand-by compressor d) Small diesel engine generator(90kVA Class) including battery, battery charger, minimum one(1) fuel oil tanks, etc. 6.17.4.11 Other mechanical requirements; a) Each auxiliary system supplied by the Bidder shall be complete with sufficient pressure, temperature, level, flow, and differential pressure instruments for control and monitoring of the system. b) Exhaust thermocouples shall be in accordance with JIS. c) Each pump, except those mounted inside of equipment shall be provided with local pressure indicators in the suction and discharge. d) Each cooler, except those mounted inside of equipment shall be provided with local temperature indicator at the inlet and outlet. e) Pneumatic instruments and controls shall not be used. f)
The Bidder shall provide process temperature connections 25mm(1inch) NPT and pressure connections 20mm(3/4inch) NPT for connection of monitoring instruments.
g) A complete set of foundation bolts, nuts, plates and washer for the diesel generator unit where required, shall be supplied by Bidder to anchor the engine generator to the foundations. h) One set of special tools, required for regular operation, maintenance, and repair of the diesel generator unit shall be supplied for the station. i) The Bidder shall be responsible for sizing and providing anchor bolts and nuts. 6.17.5
Electrical and Control System Design Requirements
6.17.5.1 The diesel generator unit shall be capable of picking up and sustaining the guaranteed loads continuously with operating limit Values complying with ISO 8528-5 Class G2.
6.17-5 KHABAT TPP UNITS 1&2 - VOLUME I
6.17.5.2 The diesel generator set shall be equipped with the local control board which consist of the following panels; - Engine control panel - Generator control panel - Synchronization panel 6.17.5.3 The Bidder shall guarantee the diesel generator unit to be capable of attaining rated frequency and voltage within 15 sec. after receiving the starting signal. 6.17.5.4 Starting loading and operation shall be automatic upon receipt of a starting signal. The diesel engine normally will be shut down manually. For test purpose, local and remote manual starting and stopping capability shall be furnished. 6.17.5.5 The diesel generator loading shall be accomplished automatically after being started, whether for operation or test purpose. This function will be carried out by the KNOC furnished load-sequencing system. The loading shall commence as soon as the generator-rated frequency and voltage are reached. 6.17.5.6 The generating unit shall be provided with protection equipment which shall protect the alternator/generator set from damage due to fault conditions. All relays or similar equipment for overspeed, oil pressure, cooling water level and high cooling water temperature, directly associated with the prime mover shall be mounted on the generating set engine and associated with a suitable trip relay. Protection equipment shall be provided and arranged to trip the associated circuit breaker, suppress the excitation and shut down the prime mover if faults should occur. 6.17.5.7 The Bidder shall provide provision for the following remote control features on ECS in the CCR: a)
Manual start and stop selection
b)
Auto/Manual synchronizing selection(Auto-Off-Man)
c)
Voltage selection for synchronizing
d)
Governor Control (Raise-Lower)
e)
Voltage Control (Raise-Lower)
f)
Synchronizing CB closing switch
6.17-6 KHABAT TPP UNITS 1&2 - VOLUME I
6.17.5.8 Auto-manual selector switch Equipment and necessary panels and wiring shall be supplied by the Bidder to provide the following local control features :
6.17.5.9
a)
Emergency stop push button
b)
Manual start and stop control switch
c)
Auto/Manual synchronizing selector switch
d)
Voltage selector switch for synchronizing
e)
Frequency control switch
f)
Voltage control switch
g)
Auto-manual selector switch
h)
Local-remote selector switch
i)
Generator breaker close-trip control switch
j)
D/G master on-off switch
The control panel shall include, but not be limited to the following instrumentation to monitor the emergency diesel generators during operation. a)
Frequency meter
b)
Excitation voltmeter & ammeter with transfer switch
c)
Generator output ammeter with transfer switch
d)
Generator output voltmeter with transfer switch
e)
Generator output wattmeter
f)
Power factor meter
g)
Watt hour meter
h)
Engine speed
i)
Running hour meter (RH)
j)
Temperature indicator, digital type, with alarm contact
k)
Pressure indicator, digital type, with alarm contact
l)
Level indicator, digital type, with alarm contact
m)
Automatic voltage regulator (AVR)
Digital type
6.17.5.10 The instrument panel shall include, but not be limited to the following instrumentation to monitor the emergency diesel generators during operation. a)
Exhaust gas temperature
b)
Jacket water temperature
c)
Lubricating oil temperature 6.17-7 KHABAT TPP UNITS 1&2 - VOLUME I
d)
Lubricating oil pressure
e)
Compressed air pressure
f)
Fuel oil pressure
g)
F.O day tank level
h)
Water expansion tank level
6.17.5.11 The generator control panel shall include a master "Station in control" onoff selector switch that will disconnect all remote control and automatic start features. 6.17.5.12 The Bidder shall provide sufficient mechanical and electric instrumentation to survey the variables required for successful operation and to generator abnormal and trip signals required for alarm for the following systems. a)
Starting air system
b)
Lubrication oil system
c)
Fuel oil system
d)
Cooling water system
6.17.5.13 The following conditions shall be alarmed on a Bidder furnished visual annunciator, and an audible alarm buzzer as a minimum. The sequence of operation of all alarms shall be ISA-S18.1, sequence M. a)
Lubricating oil pressure low
b)
Jacket water temperature high
c)
Fuel oil day tank level low/high
d)
Compressed air pressure low
e)
Water expansion tank level low
f)
Speed or frequency high/low
g)
Voltage high/low
h)
Engine running no load
i)
Alarm system failed
j)
Engine start switch not on REMOTE
k)
Oil mist high
l)
Start failure
m)
Control power failed
n)
L.O filter pressure differential high
o)
F.O filter pressure differential high
p)
Generator bearing temperature high
q)
Generator overcurrent trip 6.17-8 KHABAT TPP UNITS 1&2 - VOLUME I
r)
D/G trouble(electrical or mechanical failure)
6.17.5.14 The protective devices that function to shutdown the diesel generator shall comprise the following : a)
Start failure
b)
Engine overspeed high-high
c)
Jacket coolant temperature high-high
d)
Lube oil pressure low-low
e)
Generator bearing temperature high-high
f)
Emergency stop
6.17.5.15 The diesel generator shall also be designed for automatic operation. Equipment shall be supplied for automatic loading. This equipment shall include, but not be limited to : a)
Speed governor
b)
Automatic voltage regulator
c)
Overspeed protection
d)
Overload alarms
6.17.5.16 The Bidder shall provide devices to signal that the diesel generator has reached rated voltage and frequency and is ready to accept load. The output of these devices shall be used to initiate closure of diesel generator circuit breaker and load sequencing. 6.17.5.17 The Bidder shall provide the synchronizing equipment at the local control panel. This equipment shall include, but not be limited to; a)
Synchroscope
b)
Dual indicated voltmeter
c)
Dual indicated frequency meter
d)
Synchronizing switch
6.17.5.18 The diesel generator unit shall utilize two(2) separate control and auxiliary power supplies for redundancy. The Bidder shall provide a automatic transfer scheme for the above two separate power supplies. 6.17.6 6.17.6.1
Generator The generator shall be designed for single-operation and for parallel running.
6.17-9 KHABAT TPP UNITS 1&2 - VOLUME I
6.17.6.2
The diesel generating set shall be complete with a direct driven generator together with automatic voltage control equipment (AVR). The AVR shall be of well established design selected in conjunction with the other features of the diesel generating set offered, to ensure trouble free operation.
6.17.6.3
Three phases sensing of the AVR shall be used to minimize the effect of the waveform distortion caused by load. The generator shall be fitted with a fully linked damper winding to keep the sub-transient reactance to a minimum.
6.17.6.4
The generator frames shall preferably be of fabricated construction and incorporate an exciter. The generators shall be air cooled, insulation shall be to at least Class F with temperature rise to the next lowest class of insulation.
6.17.6.5
A solid coupling shall connect the generator rotor to the diesel engine crankshaft.
6.17.6.6
Generator rotor shafts shall be machined all over to accept the cooling fan and the rotating field assemblies for the generator and exciter, all of which shall be readily detachable for maintenance purposes. The whole rotor assembly shall be statically balanced on completion.
6.17.6.7
Deviation Factor: 10 percent maximum, open circuit, line to line terminal voltage.
6.17.6.8
Adjustable Frequency range: 48 to 52 Hz for synchronizing.
6.17.6.9
Overspeed: To withstand an overspeed of 20 percent 2 minutes without mechanical injury.
6.17.6.10
Maximum Momentary Overloads: To carry 30 seconds overload of 50 percent of normal rated current.
6.17.6.11
The generator shall be provided with space heaters which shall be singlephase with operating 230 Volts AC.
6.17.6.12
Terminal connections, including those for neutral earthing, space heaters shall be made in terminal boxes to be provided by the Bidder.
6.17.6.13
The diesel generator frame shall be provided with two earthing copperfaced pads located on the corners of the generator frame. The pads shall be furnished with solderless connectors for 120mm2 copper earth cables. 6.17-10 KHABAT TPP UNITS 1&2 - VOLUME I
6.17.6.14
The diesel generator neutral earthing cubicle including resister shall be provided. The rating of resister shall be as follows;
6.17.7 6.17.7.1
Exciter and voltage regulator The generator shall be provided with a brushless exciter with fast response voltage regulator, including necessary power, current and potential transformers.
6.17.7.2
Automatic voltage regulation shall be within ±2½ percent at rated kVA, power factor and frequency.
6.17.7.3
The regulator shall provide for manual operation, independent of the automatic control, and have a manually adjustable voltage set point.
6.17.7.4 6.17.8
The Bidder shall provide a rectifier fault detector and monitor. Piping and valves If the connecting type of piping, the Bidder shall design, supply the isometric drawing shown on interconnecting piping considering the arrangement of equipment for the Bidder, and also submit necessary counter flange, gasket, packing and bolts/nuts/washers for counter piping.
6.17.9 6.17.9.1
Drives When equipment is V-belt driven, the drive shall be in accordance with manufacturer’s standard.
6.17-11 KHABAT TPP UNITS 1&2 - VOLUME I
6.18
Service Gas System The service (N2) gas supply system including the gas storage facility shall be provided for unit preservation against oxidation during long periods of plant shut down. The system shall be installed in common use for two (2) units. The N2 gas supply system and the scope of supply shall be generally as shown on the Bid drawing. A.
N2 gas shall be supplied to following portions during long period of plant shut down. 1) Boiler 2) High and low pressure feed water heaters 3) Deaerator 4) Other portions, if required
B.
The N2 gas supply system shall include, but not be limited to the following: 1) N2 gas, bottles and bottle racks 2) Pressure reducing and control equipment 3) All necessary piping, valves, connections and accessories for each unit
The volume of N2 gas storage shall be sufficient to provide at least one (1) times of filling in empty one (1) unit after blowout of boiler water. The N2 gas bottles shall be provided in some groups to enable to switch supplying line from each group. The N2 gas bottles shall be of standard type available locally with appropriate fill pressure. The storage area shall be arranged to comply with the appropriate standards and safety regulations with provisions for easy removal of gas bottles.
6.18-1 KHABAT TPP UNITS 1&2 - VOLUME I
6.19
Fire Protection and Detection
6.19.1
General requirements All plant and buildings shall be designed and arranged to minimize the possibility of fire hazards originating from them or spreading to them from a fire in the vicinity. Plant and cables shall be segregated to reduce fire risk, damage and multiple shutdowns. Electrical equipment located in hazardous areas shall be explosion proof, flame proof, intrinsically safe or otherwise designed to be suitable for the location zone. The Bidder shall provide all calculations for all of the fire protection systems; conduct the design, procurement, equipment and system installation and subsequent testing. All shall comply with the applicable NFPA and related Code requirements, applicable national and local Codes and Standards and local Fire Department (FD) regulations and shall be subject to approval by the KNOC. All equipment and valves etc shall be FM and UL approved and listed.
6.19.2
Scope of supply The scope of the fire protection and detection system shall include but not be limited to the following: A.
fire fighting water supply system, comprising fire water storage (dedicated reserve of raw water tank), main electrical motor driven and standby diesel engine driven pumps, jockey pumps, and Fire water mains;
B.
automatic water spray deluge protection for all oil filled transformers and cable floors, steam turbine lub oil system and surrounding floor area (manual protection for steam turbine bearings);
C.
automatic water sprinkler system for steam turbine cable tunnels, and for stores and workshop;
D.
manual-initiated water sprinkler system for burner areas of boilers;
E.
fire detection for burner areas of boiler;
F.
fire detection for air heaters;
G. manual initiation of water sprinkler system for air heaters; H.
automatic foam/water spray deluge protection for fuel oil pump house;
I.
remote/local manually initiated foam protection for the fuel oil tanks and the bund area and spray cooling water system for fuel oil tanks;
6.19-1 KHABAT TPP UNITS 1&2 - VOLUME I
J.
standpipe and hose reel/hose rack cabinet system in the buildings and plant areas;
K.
yard hydrants and yard hose cabinets;
L.
gas extinguishing fire protection system for switchgear rooms, panels, instrument room and control rooms;
M. fire protection system for fuel gas scrubber and boosting station; N.
portable extinguishers in all the buildings;
O. comprehensive site fire detection system with master alarm panel in Control Room and repeater panel in gatehouse. 6.19.3
Fire water supply
6.19.3.1 Fire water storage Water for fire fighting purposes will be treated raw water. An indicative analysis of raw water is provided in Volume 2, Schedule A. A dedicated reserve of water for fire fighting shall be stored in a combined raw/fire water tank - refer to Section 6 for details. 6.19.3.2 Fire water pumps One 100% duty electric motor driven pump and one 100% duty diesel engine driven pump shall be supplied, each pump capable of supplying water to all sprayers, sprinklers, hydrants or hose reels associated with the largest single fire risk and comply with the requirements of NFPA 20. The pumps shall be of the horizontal axis centrifugal type with flooded suction. Details of the pump characteristics shall be submitted for approval. The design of the diesel engine, in particular its lubricating system, shall be such that periods of long standing will not affect the starting up of the diesel engine. The fuel supply tank shall have a capacity such that the diesel engine can be run at full load for at least [eight] hours. The outlet from the tank shall be at a height of not less than 600 mm above the inlet to the fuel injection pump on the engine. A trickle charger system shall be provided suitable for keeping the starting battery fully charged. In the event of fire water demand within the site the duty electric pump shall start on sensing low pressure in the main. The diesel pump shall start if the pressure remains low after a 5 second delay, or falls due to high demand. Each pump discharge shall be fitted with a full flow recirculation line to the 6.19-2 KHABAT TPP UNITS 1&2 - VOLUME I
storage tank to facilitate pump testing. Isolating valves normally locked closed shall be fitted to these recirculation lines. Pressure relief devices shall be provided to protect the pumps under low flow conditions. One 100% duty jockey pumps shall be provided to maintain the fire main under pressure and to cater for minor usage/leakage. The status of each pump shall be indicated on the master fire alarm panel. The fire pumps shall be located within a building to give adequate protection from the environmental conditions. 6.19.3.3 Fire main The pressurized fire main shall be designed on a ring main basis and sized to cater for the maximum water demand in accordance with NFPA 24. Valves (normally locked open) shall be fitted at appropriate points in the main to allow isolation of discrete sections of the site. All thrust blocks (if required), valve pits, vent and drain connections and corrosion protection measures are to be provided. The capacity and layout of the main, and the position of hydrant outlets shall be submitted for approval after award. 6.19.4
Fire fighting systems
6.19.4.1 Automatic water spray deluge system Automatic water spray deluge systems shall be provided for the protection of oil filled transformers, cable floors and for the steam turbine lubricating oil piping, all in accordance with NFPA15. Deluge system for the transformers shall be operated by a pneumatic detection systems and for cable floors shall be operated electrically. The pneumatic detection system shall derive instrument air from the station air distribution system. The alarm system shall be as described in Section 8. Local manual push button release of deluge valves shall also be provided. Steam turbine generator bearings shall be protected by a manually initiated spray water deluge system. The bearings shall be provided with shields to prevent discharge of water onto hot turbine parts and control valves shall include contacts to transmit system activated signal to the CCR. 6.19.4.2 Automatic wet pipe sprinkler alarm system A wet pipe sprinkler and alarm system shall be provided for the steam turbine building, and workshop and stores buildings. The sprinkler systems shall 6.19-3 KHABAT TPP UNITS 1&2 - VOLUME I
operate on the ‘Quartzoid’ bulb principle and shall detect an outbreak of fire and distribute water automatically over a predetermined area. The installation shall be in accordance with NFPA 13 and local FD regulations for sprinkler installations. Alarm valves shall be provided with a retarding chamber. Operation of each individual sprinkler zone shall initiate an alarm after a time delay on the fire alarm system specified in Section 8. The alarm shall be initiated by a suitable flow switch type alarm valve. 6.19.4.3 Automatic foam/water spray deluge systems The design of these systems shall be in accordance with NFPA 11 or 11A as appropriate and FD regulations and water shall be taken from the underground hydrant ring main. A.
Balanced pressure proportioning system. The fuel oil pump house shall be provided with balanced pressure proportioning system with aqueous film forming foam (AFFF), capable of a 3% mixture in service water, shall be stored in the foam concentrate storage tank. The capacity of the tank(s) shall be twice the size of the calculated foam charge. Two positive displacement foam concentrate pumps (duty and standby) with automatic regulating valves shall draw foam and inject into the water supply via proportioners. The thermal detectors located in the fuel oil pump house shall initiate operation of the deluge valve through the fire alarm panel.
Operation of
the deluge valve shall start the foam concentrate pump and open the foam concentrate motor operated isolating valve. Local manual push button station shall also be provided. B.
Diaphragm pressure proportioning system. The diesel engine fire pump including its fuel oil day tank shall be protected by foam/water which shall be provided from a diaphragm type foam concentrate proportioning tank via an in line injector. The water supply for automatic foam/water system for the fuel transfer pump house shall be fed from the fire main. An automatic control panel located in the boiler control room and a manual push-button station with complete alarm indication/annunciation to the master fire panel shall be supplied. The size of the foam tank shall be suitably sized (1 m3 minimum). The foam concentrate shall be AFFF capable of a 3% mixture in service water. 6.19-4 KHABAT TPP UNITS 1&2 - VOLUME I
The thermal detectors located in each protected area shall initiate through the firm alarm panel, the operation of the deluge valve and solenoid valve which shall open a piston operated ball valve to pressurize the bladder and eject foam through the proportioner.
Local push button stations
shall also be provided. 6.19.4.4 Remote/manual foam system and water spray system The fuel oil storage tanks and bund area shall be protected with a remote manual foam system, comprising foam injection system, bund pourer system, and foam monitor system (located on the fuel oil tank bund wall), and a remote/manual spray water cooling system, sized to cool a full tank. All systems shall comply with the requirements of NFPA 11 or 11A as appropriate and 16. The foam systems shall be supplied from the foam station comprising foam concentrate tanks, foam concentrate pumps, motor operated valve and proportioning equipment. The fire water supply shall be obtained from the underground ring main. The oil tank foam injection, bund pourer, foam monitor and cooling water spray systems shall be controlled remotely from the foam station. Operation of the deluge valve shall automatically start the foam concentrate pump and open the foam concentrate isolating valve. Local manual release push button station shall also be provided. 6.19.4.5 Fuel oil tank foam injection system The foam concentrate shall be fluoroprotein foam capable of a 3% mixture in desalinated water. One foam station shall be provided for the injection of foam into each group of fuel oil tanks. The foam station shall comprise one concentrate storage tank, two positive displacement concentrate delivery pumps (duty and standby), one balance pressure proportioner and all associated pipe work, motor operated valves and deluge valves. The design and capacity of foam pumps and chambers shall be based on foam concentrate injection rate calculated in accordance with the codes. The foam concentrate storage tank shall be sized to hold two times the calculated foam charge to protect the fuel oil tank. Each foam chamber mounted on the fuel oil tank shall have a rupture disc assembly provided on the foam discharge outlet, to ensure that the foam 6.19-5 KHABAT TPP UNITS 1&2 - VOLUME I
system is not contaminated by oil should an overflow occur. 6.19.4.6 Fuel oil tank farm bund area foam pourers The oil tank bund area shall be provided with foam pourers, equally spaced along the bund walls of each oil tank bund area which shall be capable of covering with foam/water the entire bund area (including the oil tank) and shall be supplied with foam water from the main pipe work ring located outside the bund. The details of the system shall be as described for the Tank Foam Injection system. 6.19.4.7 Foam monitors system Motor operated oscillating type foam monitors complete with pipe work and valves shall be provided and placed on the bund walls. At least three monitors shall cover the tank and its bund area. Monitors shall be capable of operating at the fire system pressure and reaching the top of oil tank from any direction. Monitors shall have horizontal and vertical movement in any combination thereof to give a complete arc of operation over the bund area with locking facilities to allow manual operation from any position. Monitors shall be of stainless steel construction and be provided with motor operated valves. Access platforms and ladders shall be provided as necessary to facilitate operation and maintenance of all monitors, valves and equipment. One foam station shall provide the bund pourers and foam monitors located on the tank bund wall. Each system shall be fitted with motorized isolating valve. The foam concentrate storage tanks for foam pourers and monitors shall be sized to hold two times the calculated foam charge to protect one oil tank. 6.19.4.8 Spray water cooling system for the fuel oil tanks The fuel oil storage tanks shall be protected by a remote/manual controlled spray water cooling system. The system shall be supplied with water from the underground site hydrant water supply system. The design and construction of the cooling system shall comply with the requirements of NFPA 15 of VdS 2109. Run off spray water shall not be taken into account in the design of the cooling system.
6.19-6 KHABAT TPP UNITS 1&2 - VOLUME I
The system provided for the tank shall be divided equally into four hydraulically balanced quadrant systems, the operation of any one quadrant or combination of quadrants being individually controlled automatically and also from local manual release push button stations. Each tank quadrant shall be provided with headers individually piped to a motorized control valve position suitably located outside the bund wall. A number of frangible bulb temperature detectors shall be provided on the external periphery of the tank shell adjacent to the tank roof to activate the cooling water spray system and to raise alarm on the main fire alarm panel located in the control room. Each control valve shall be provided with all fixtures necessary for test, and operation, and shall include manual override facility for emergency manual operation. Pressure switches shall be provided for each deluge valve to provide ‘system activated’ signal to the fire alarm panel located in the Control Room. 6.19.4.9 Standpipe and hose cradle/reel cabinet system Each building shall be provided with a standpipe system complying with NFPA 14 and designed to give Class [III] service. The Bidder shall provide fire hose reels and hose cradles in each building. Fire hose reel cabinets shall be equipped with a 30 metre length of 25 mm diameter double braded rubber, non collapsible hose mounted on reel drum which shall be of the swinging arm type. The hose reel connected to the water supply shall be supplied with DN25 isolating ball valve and DN25 pressure reducing valve and adjustable spray/jet nozzle. Hose cradles shall consist of a 30 metre length of 40 mm lined, collapsible, synthetic hose mounted on a hose rack which shall be of the swinging arm type. Both hose reels and hose cradles shall be equipped with quick coupling type of gun metal with adjustable jet/spray nozzles. A single 65 mm
automatic
pressure regulating
valve
with
female
instantaneous coupling connection shall be provided in each hose reel/hose rack cabinet, connected separately to the water supply inside the cabinet and available for the connection of Fire Brigade hoses even when the hose reel/hose rack is in use. The hose reel/hose rack cabinet shall be made from galvanized steel with double glass door clearly labelled “FIRE” in Arabic and English and painted red with white lettering to an approved procedure. Each hose reel/hose rack 6.19-7 KHABAT TPP UNITS 1&2 - VOLUME I
cabinet shall also be supplied with one (1) unit of 9-10 kg dry power fire extinguisher for class ABC fires. 6.19.4.10 Site fire hydrant system 6.19.4.10.1 Fire hydrants The arrangement of the site fire hydrant system shall comply with the requirements of NFPA 24 and shall generally comprise a buried sectionalized ring main, distribution pipe work complete with post indicator valves, isolating valves wash-out valves and valve pits. The distribution network shall provide supply of water to each standpipe system, automatic spray foam and water deluge system, fire hydrants positioned around the power station site and the main oil tank area fire protection systems. All fire hydrants shall be installed at a spacing not greater than 60 m and shall comply with FD requirements. Fire hydrants shall be constructed from cast iron (150 mm) with two DN65 globe valve couplings, cap, chain and a 100 mm connection for fire engine pump suction. Each fire hydrant shall be provided with an auxiliary valve with curb box. Curb box assembly shall be cast in concrete at grade and depth of cover shall be adjusted to the proper depth of pipe. The valve shall be key operated with an operating key provided at each outdoor hydrant cabinet. Each fire hydrant and post indicator valve position shall be protected from damage by four vertical guard rails painted with red and white bands. Where direct buried these shall be protected by suitable sleeving and backfilled with selected material approved by the KNOC. Post indicator valves shall be butterfly type and provided at all branch lines and for sectionalizing portions of the water network and shall meet UL design requirements. The stem length of the post indicator valves shall match the site gradient and hydrant main invert. 6.19.4.10.2 Outdoor hose storage cabinets and equipment The Bidder shall provide one outdoor hose storage cabinet at each hydrant location, comprising weatherproof steel cabinet complete with a break glass lock mechanism. Each cabinet, mounted on a concrete foundation shall contain, as a minimum: A.
One (1)
hydrant turnkey and bar
B.
One (1)
65 mm hose standpipe with instantaneous outlet connections
C.
Three (3)-25 m lengths of 65 mm light synthetic fibre imperviously jacketed hose with light alloy instantaneous couplings 6.19-8 KHABAT TPP UNITS 1&2 - VOLUME I
D.
One (1)
Jet/spray - on/off nozzle
E.
One (1)
65 mm hose branch pipe 22 mm bore nozzle
F.
One (1)
Fire axe and crowbar
6.19.4.10.3 Fire hose The fire hose shall be light and flexible besides being resistant to abrasion and damage due to contact with chemicals or oil.
The hose shall comply with
the relevant internationally recognized codes and standards. The bursting pressure of the hose shall not be less than twice its working pressure. Hose is to be 65 mm gauge and supplied in 25 m lengths with male and female
instantaneous
couplings
compatible
with
local
requirements/regulations. 6.19.4.10.4 Jet/spray - on/off branch pipe nozzle These nozzles shall emit a powerful straight jet, atomized spray or a wide spreading cone of solid water and shall include fog and shut off features. The type of spray shall be adjusted by twist control. Nozzles are to be manufactured in light alloy and fitted with a stainless steel valve cone and designed for maximum velocity at the minimum restriction to flow. The inlet shall be a male instantaneous coupling. 6.19.4.10.5 Standard water branch pipe Branch pipes shall comply with the relevant internationally recognized codes and standards. The inlet shall be a male instantaneous coupling. The outlet shall be 5/8” diameter to give a high power straight jet of water. 6.19.4.10.6 Fuel gas treatment (AGI) system The AGI for the gas system shall be protected by the yard hydrants which shall be located near this area at spacings as specified. The area shall also be provided with a fire detection system as described in section 8. 6.19.4.10.7 Portable extinguishers The following types of portable fire extinguisher equipment complying with NFPA 10 shall be provided and installed at agreed locations including wall mounting, in the plant and building areas. A.
9-10 kg capacity dry power extinguishers for use against oil fires associated with electrical equipment. The powder shall be expelled from the extinguisher by compressed CO2 gas and controlled by a pistol grip nozzle attached to the discharge hose. 6.19-9 KHABAT TPP UNITS 1&2 - VOLUME I
B.
9-10 kg and 6 kg capacity CO2 extinguishers for use against fires associated with electrical equipment. The extinguishers shall be provided with fixed discharge horn and trigger valve control and trolley where required.
C.
9-10 litre/capacity CO2 gas pressure operated water extinguishers for use against ordinary small fires. The discharge nozzle shall be supplied with flexible hose and the control shall be such that intermittent control is possible.
D.
9-10 litres capacity foam extinguishers for use against small oil fires. The extinguishers shall be pressurized with CO2 gas.
The number and types of extinguisher per building are to be advised in the Tender and shall be in accordance with the recommendations given in NFPA 10 and shall be to the KNOC approval. 6.19.4.11 Fire detection and alarm system The fire alarms system shall be complete in all respects and shall include the main and local fire alarm/control panels, the fire detection system, the alarm contacts for local and remote signaling, all cabling between the fire detectors and alarm contacts and the local and main fire alarm/control panels. Refer to Section 8 for details regarding the fire and gas detection and fire alarm systems.
6.19-10 KHABAT TPP UNITS 1&2 - VOLUME I
6.20
Cranes and Lifting Equipment
6.20.1 Conditions of service 6.20.1.1 Description of service A. The Bidder shall furnish lifting device with associated support, rails, runways and lifting eyes required for the adequate maintenance weighting in excess of 25kg any equipment. B. The overhead traveling cranes are indoor installations. The turbine over head crane will be used to service the generator rotor and other equipment and components within the turbine building for construction, and maintenance. C. The adegunit type cranes at the raw water intake (one for the bar screen area and one to serve the traveling band screens) are installations and for construction and maintenance, respectively. D. The overhead traveling cranes will be preferably operated in longitudinal direction of the subject building. Each crane shall be capable of handling the heaviest part and the part with a certain overall length installed in the subject building, i.e. the stators of the alternators E. In the case of the steam turbine building the traveling crane lifting height shall be designed for lifting the turbine rotor of the lower part of the turbine casing, as also for lifting the LP heater tube nests out of their shell or shells above tops of the tube nests, up to the steam turbine building floor F. Wherever required, local hoists (monorails) shall be installed for proper handling and maintenance of equipment. According to specific needs, the hoists can be permanently installed or can be removable. They can be electrically or manually operated. G. The B.F.P underhung crane will be used to service the B.F.P and auxiliaries components in the B.F.P area for construction and maintenance. H. All cranes will be used during plant construction for lifts up to the crane rated load. 6.20.1.2 Design conditions A. General The cranes, hoists and lifting devices shall be used primarily for unloading, installation and future maintenance of the mechanical and electrical equipment. The Bidder is not bound to adopt the crane design outlined in 6.20-1 KHABAT TPP UNITS 1&2 - VOLUME I
the drawings, but he shall observe all governing dimensions shown there. Regarding the outer appearance, the crane shall be pleasant from an aesthetic point of view, and the mechanical and electrical equipment shall be fully protected from the influence of dust and high salty air humidity at the Site. The crane drive and trolley arrangement shall be designed to require a minimum of space while optimizing the accessible working area. Furthermore, the design shall provide easy accessibility of all important parts which require regular maintenance and inspection. The maximum full load starting speed shall be 10% (ten per cent) of the maximum operating speed for the crane hoists, the gantry drive and trolley drive. Electrical driven cranes hoists and lifting equipment shall have a nominal and a creep speed. The crane shall operate within the following tolerances : With the hook carrying 125% (one hundred and twenty-five percent) of the nominal load and with the hoist brakes properly set and operating under normal conditions, the vertical motion at the rated inching speed shall be controllable within 3 mm. The crane will be installed indoor or outdoor, and building temperature and relative humidity are indicated in General Design Condition. B. Additional Seismic Requirement Seismic requirements shall be in accordance with Seismic Zone. All cranes shall be designed to withstand seismic conditions, including the horizontal and vertical seismic forces combined with the gravity load. Positive means shall be provided on the crane to prevent bridge, trolley, or any other part from falling on structures or equipment below the crane in the event of an earthquake. The holding brakes or restraining lugs, using normal design stress, shall be designed to prevent the trolley and bridge from falling during an earthquake. 6.20.2 Design and construction features 6.20.2.1 General The crane to be furnished under this Section of the specification shall be of rigid frame design. All equipment and components shall be in conformance with codes and standards. 6.20.2.2 Material standards The material to be used for manufacturing the lifting equipment steel structures 6.20-2 KHABAT TPP UNITS 1&2 - VOLUME I
shall conform to the equivalent ASTM standards. However, the Bidder shall restrict the structural steel to St. 37-2 and St. 52-3 or ASTM A 36; the latter may be regarded as equivalent to St. 42. 6.20.2.3 General design particulars A. Nameplates stating the nominal load capacity in kg or tons shall be attached to both sides of the lifting equipment structure and to both sides of the rope block. The printing shall be clearly legible from the floor. Flexible couplings shall be installed to relieve the bearings and shafts from any stresses due to misalignment and to facilitate the removal of motors, wheels and gears. The motor couplings also shall be of the flexible type. All couplings, drive wheels and gears shall be press fit and keyed to the shaft. All wheels shall have a hardened tread with a minimum Brinell hardness number of 320, and shall be made of carbon steel or low-alloy steel forgings. They shall have double flanges, shall be machined to a uniform diameter concentric with the hub bore. All bearings preferably shall be anti-friction bearings designed to permit easy shaft disassembly and easy replacement. The minimum average lifetime under design load conditions shall be 5000 hours. All bearings except those for the hooks and rope sheaves shall be lubricated by central lubrication systems. An independent system for the trolley and one for two independent systems for the bridge will be acceptable. All gears shall be designed and executed as bevel gears. For all high-speed gears and pinions, oil bath lubrication shall be provided. Low-speed gears may be lubricated with soft grease. Suitable oil and grease catching drip pans shall be installed and be readily accessible for draining and cleaning. B. Trolley The trolley frame shall be made of welded structural steel and shall have a rigid construction to ensure a uniform distribution of the loads to all wheels without undue deflection. After manufacture, the trolley frame shall be stress-relieved. Flexible bumpers shall be provided at the ends of the trolley frame; they shall be designed to absorb the impact forces arising when the trolley, running at maximum speed with the nominal load suspended from it, is stopped with the motor switched off. Removable track sweeps shall be furnished, and the trolley frame shall be fitted with safety grips to prevent the 6.20-3 KHABAT TPP UNITS 1&2 - VOLUME I
trolley from leaving the rails and to limit the maximum sag of the trolley to 20 (twenty) millimeters in the event of any one wheel assembly breaking. The trolley shall be driven by an electric motor mounted on the trolley frame and connected through gearing and an axle to one wheel on each track. C. Ropes The wire ropes for the hoists shall be of twist-free construction preferably with a fiber-core; the wires should consist of hardened and tempered plow steel. They shall be long lay-ropes with heavy-duty permanent lubrication. The stresses in the ropes shall be assumed at the maximum point and shall include the overall efficiency of the hoist in the parts of the line from the drums as well as the weight of the load, hook, and rope sheaves. The ropes shall be attached to the drum in a simple and safe manner so that for their adjustment and replacement, only a minimum number of parts need to be removed. D. Drums The drums shall have machined grooves to the right and left to receive the ropes. The center of the drums shall not be grooved. The drum bullgear shall be press or shrink fit to it and secured by dowels or keys or similarly fastened to the drum shaft if the drum is driven through the shaft. The drum shall be dimensioned adequately to leave at least three complete windings of the lifting rope in the grooves on each side with the hook in lowest position for the specified lifting distance, and it shall not be necessary for the rope to be wound in a double layer when the hook is in its highest position. E. Sheaves and Blocks The rope sheaves shall be cast steel or steel weldments with machined grooves which have suitable diameter tolerances and are sufficiently smooth to minimize wear on the ropes. The sheave pins shall be made of annealed carbon steel or steel alloy and shall have an ample sheave bearing surface. All moving sheaves shall be fitted with roller bearings, each suitable for force-feel fabrication; they shall be accurately balanced for smooth running. The load blocks shall be built so that they will entirely surround the lifting ropes and will prevent the rope from coming out of the sheave for all operating conditions. The rope-guard shall be of grease-tight cast steel or welded construction and shall fit close to the rope sheave circumference. 6.20-4 KHABAT TPP UNITS 1&2 - VOLUME I
F. Hooks The load hooks shall be made at forged steel subject to the KNOC approval; the yield point shall be approximately two thirds of the ultimate strength. The hooks shall be load tested to 150 % of the rated load and x-rayed of magnafluxed after testing to ensure that there is no hidden damage to the hooks. The hooks shall be finish-ground by hand and shall rotate freely on anti-friction bearings. The bearings shall be totally enclosed, dust-tight and properly sealed to avoid the egress of grease. The main hoist shall be equipped with a double hook in accordance with DIN 15402. G. Brakes The main hoist and the auxiliary hoist shall be equipped with brakes. Holding the load shall be effected by means of an automatic springset, electrically or elctro-hydraulically released double shoe-type brake. The brake capacity shall be not less than 200 % of the torque caused by the maximum nominal load of the crane. The brake must prevent the load from descending until the hoist motor is energized for operation in the lowering sense. The load control brake preferably shall be an electrical brake, working on the basis of frequency transformer control. An electrical brake of the eddy-current type or a combination of electrical and mechanical brakes also will be accepted. Friction load braking will not be accepted. Bridge and trolley drives shall be equipped with a spring-set, electrically (solenoid or electro-hydraulic) released shoe or disc brake, whose capacity shall be at least 1.5 times the full operating torque of the drive. The brake shall be applied when the motor control switch or the main power switch is in the "off" position and/or when the current fails on any one phase. The braking action shall be gradual and the brake shall become fully effective after a certain time lag. Remote Wireless Pendant Control with hard wired pendent as back up. Auto crane movement audible alarm signaling crane movement/operation.
6.20.2.4 Instrumentation control equipment and electrical equipment The crane control system shall be the full magnetic type, complete with main circuit-breakers, master switches, controls, resistors, time or current relays, reversing contactors, overload relays, auxiliary relays, accelerating contactors, limit switches and all other accessories required for speed and operating control as specified. 6.20-5 KHABAT TPP UNITS 1&2 - VOLUME I
The coils and contacts of the magnetic control must be enclosed in metal cabinets. The Manufacturers shall supply detailed information about the materials used in these components, such as contact life, closing and opening time of the contacts, etc. The main contacts shall be able to operate without excessive wear, overheating, sticking or any other malfunctioning. The electrical control devices shall be installed in panels and steel cubicles mounted on the crane girder. All controls shall be conveniently grouped in a panel to enable the operator to operate the crane from a point where he can best watch all crane movements, by means of a pendant switch control panel respectively by means of wireless control. All master switches, hand-operated switches, circuit breakers, contactors and relays shall be distinctly and durably marked. The control switches shall be reversible. All control switches shall be accommodated in adequately ventilated sheet steel housings. Each of the housing shall have a small heater to prevent condensation. The heating system shall be controlled by a thermostat which will disconnect the current in the event of an undue temperature rise. The resistors shall be air-cooled, and corrosion and fire-resistant. They shall be dimensioned adequately to withstand all stresses from the crane movements. A. Limit Switches The crane shall be equipped with the following enclosed limit switches of the closed-circuit type : 1) Block-actuated switches to limit upward travel of the load blocks; 2) Two switches to limit travel of bridge and trolley in both directions; first switch to reduce the speed to creep speed 0.5 m before the end position is reached, second switch to stop at the end position, 3) Lower hoist limit switch, gear or chain-driven from drum (on auxiliary hoists acceptable for upper and lower hook position). 4) Limit switches shall be arranged to reset by reversing the associated controller. Only the motion being limited shall be affected by tripping the limit switch. B. Motors The motors to be provided shall be induction motors with adequate rating to cope with the load involved. Motors of relatively low-speed shall be given preference. The motors shall comply with Section 7. 1) Current Feed Cables for Trolley 6.20-6 KHABAT TPP UNITS 1&2 - VOLUME I
The current feed cables for the trolley shall be arranged so that they are readily accessible for replacement. A sufficient number of cables shall be furnished and installed so that each motor is electrically-controlled independent of all other motors and controls. Additional cables shall be provided for grounding the trolley to the ridge frame and for one socket which shall be suitably located on the trolley for maintenance purposes. 2) Cables, Cable Conduits and Terminals Cables shall be laid in rigid, galvanized steel conduits with screwed connections and draw-in boxes which shall be suitably built into the crane structure. All cables shall run to terminal strips for making the outer connections. The cables must not be spliced. All cables shall be clearly identified by suitable tags or durable markings to facilitate installation and maintenance. Separate cable conduit systems shall be provided for the power, light and control circuits. The entire cable conduit arrangement shall be grounded. The configuration of all lines, terminal strips and cables shall be subject of approval. 3) Power Supply Line for the Crane Power shall be fed to the crane by 4 (3-phase plus grounding) rigid copper conductors of the protected type located on the upstream wall of the
powerhouse.
These
conductors,
complete
with
insulating
wall-mounting brackets and collectors mounted on the crane, shall be included in the supply. 6.20.3
Control points
6.20.3.1 The cabin shall be fitted with a emergency-stop foot switch. 6.20.3.2 All cranes shall be operated from a pendant. The pendant shall be supported in such a manner as to be readily handled by a single operator. It shall control the bridge, trolley, and hoist power at either end of the bridge with the trolley at the other end. The pendant shall be provided with a traverse motor controlled from the pendant and a key to control the master switch located on the crane. The pendant control pushbuttons shall be oil-tight heavy-duty and return to off position when released. 6.20.4
Electrical overhead travelling cranes
6.20.4.1 A pendant operated overhead travelling crane shall be provided in the [Workshop, the steam turbine building], and in other plant buildings if required for maintenance of the plant. 6.20-7 KHABAT TPP UNITS 1&2 - VOLUME I
6.20.4.2 The crane shall be designed and constructed in accordance with the requirements of the relevant internationally recognized codes and standard’s and shall be complete in all respects for safe and efficient operation. 6.20.4.3 The bridge or gantry, trolley and hoist movements shall be controlled by suitable reversible controllers. The bridge trolley and hoist control schemes shall permit variable speeds in both directions of travel. Limit switches shall be provided at end limits of bridge, trolley and hoist travel. 6.20.5
Mobile cranes Mobile crane shall be diesel powered and minimum 40ton.
6.20.6
Runway beams and lifting facilities
6.20.6.1 All heavy parts of the plant supplied under the Contract shall be provided with arrangements for lifting, slinging and handling during erection and overhaul. All parts normally lifted during periods of maintenance and weighing one tonne or over shall be appropriately marked with their weight. 6.20.6.2 Runway beams shall be provided to facilitate handling of the various parts of the plant which require to be removed for cleaning and overhaul. The beams shall be supplied with trolleys for the attachment of blocks and lifting tackle and a range of suitable blocks and tackle shall be supplied. The runway beams shall comply with the requirements of the relevant internationally recognized codes and standard shall be tested after erection. The Bidder shall be responsible for the provision of the appropriate test certificates which must be in accordance with Appendix C of the relevant internationally recognized codes and standard. All necessary lifting beams and slings shall be provided 6.20.7
Testing
6.20.7.1 All cranes and lifting equipment shall be proof load tested, mechanically, electrically and operationally. The Test results shall be recorded on certificates, copies of which shall be submitted to the KNOC. 6.20.7.2 The safe working load shall be clearly marked on all cranes and lifting equipment. 6.20.7.3 Load test The hooks shall be load tested to 150% of the rated load and x-rayed of magna fluxed after testing to ensure that there is no hidden damage to the hooks. 6.20-8 KHABAT TPP UNITS 1&2 - VOLUME I
6.20.8
Use of cranes for initial erection All cranes used during the initial erection of the plant shall be refurbished to their "as new" condition before they are taken over.
6.20-9 KHABAT TPP UNITS 1&2 - VOLUME I
6.21
Laboratory Equipment These equipment are to be used for analysis and test of water, fuel and environment.
6.21.1
Design features A. Laboratory equipment and appurtenance furnished under this specification shall be designed to meet the requirements of this specification. B. The Bidder shall furnish laboratory equipment in accordance with the specification. C. Scale shall be designed to read directly in engineering units, legends, charts, scales, and nameplates shall be in the English language. D. All equipment requiring compressed air shall accept the following : instrument dry compressed air at 5～8.8 kg/cm2g. E. Unless otherwise stated in the specifications of this specification, the Bidder shall furnish the list of manufacturer's standard and optional accessories to support each item and equipment. F. Training and Technology Transfer. The Bidder shall provide training and technology transfer to the KNOC for operation and maintenance. G. The water analysis for examination of water and waste water shall have the equipment, accessories and chemicals necessary to perform, at least the following analysis. 1) Alkalinity 2) Oxygen (DO, BOD) 3) COD 4) Ammonia (NH3) 5) Calcium (Ca) 6) Hardness 7) Chlorine (Cl2) 6.21-1 KHABAT TPP UNITS 1&2 - VOLUME I
8) Chloride (Cl) 9) Conductivity, high and low concentrations 10) Copper (Cu) 11) Hydrazine (N2H4) 12) Iron (Fe) 13) Phosphate (PO4) 14) pH 15) Silica (SiO2) 16) Sodium (Na) 17) Total Solids 18) Turbidity 19) Others Magnesium (Mg) 20) Sulfate (SO4) 21) Aluminum (Al) 22) Acidity 23) Nitrite (NO2) 24) Nitrate (NO3) 25) Others H. The fuel analysis for examination of fuel and lube oil shall have the equipment, accessories and chemicals necessary to perform, at least the following analysis. 1) Low Heating Value (LHV) / High Heating Value (HHV) 2) Specific Gravity 3) Viscosity 4) Flash point 5) Acidity 6.21-2 KHABAT TPP UNITS 1&2 - VOLUME I
6) Water and Sediment in Oil 7) Others a) Materials b) Composition and physical properties of all materials shall be best suited to their purposes in accordance with the Bidder's usual practices for this type of equipment, unless otherwise specified. 6.21.2
Attachment A. Laboratory Equipment List – Refer to the C2 mechanical Schedules C2.20 1) Optional accessories specified below shall be supplied with its test equipment as scope of supply. 2) Standard accessories shall be supplied with test equipment at no extra cost. 3) Battery chargers shall be supplied with rechargeable batteries specified below at no extra cost. 4) Operation & service manual shall be supplied. 5) The installation and operation & test-run should be carried out by the Bidder at end-user's site. B. The specification in the following list is the minimum requirement, so the Bidder shall provide detailed specification and supply the latest model as of the date of purchase without any extra cost. C. The Bidder shall provide one(1) lot of laboratory equipment for two(2) Units.
6.21-3 KHABAT TPP UNITS 1&2 - VOLUME I
6.22
Workshop, Stores and Equipment
6.22.1
General A complete workshop shall be provided to enable general maintenance work, of the whole plant, to be carried out. The workshop shall be provided with an overhead travelling crane, pendant operated, of suitable capacity for the largest maintenance load. This workshop is not intended for major boiler overhaul work. A stores building shall be provided to provide suitable storage conditions for plant spare parts, consumables etc The Bidder shall furnish the services and equipment including all necessary features, components, accessories and appurtenances for the safe, efficient and reliable erection, operation and maintenance whether mentioned in this specification or not. A store building shall be provided to provide suitable storage conditions for plant spare parts, consumables etc.
A. MECHANICAL WORKSHOP MACHINE TOOLS & EQUIPMENT Item No 1 2 3
Item Description
Qty
Large Lathe (580mm dia ,swing over bed x 2000mm between centers with gap bed ) Medium Lathe (450mm dia ,swing over bed x 1500mm between centers with gap bed ) Radial drill machine (distance from center main axis to column; Min. under 300mm, Max. over 1300mm)
1 1 1
4
Flore drill machine swing 540 mm over
1
5
Universal Milling machine (table size 1100mm x 270mm)
1
6
Shaping machine table size 710 x 320mm
1
7
Metal cutting sow machine Cap. Φ450mm, 450mm x 310mm
1
B. Furnish all relevant documentation and drawings.
6.22-1 KHABAT TPP UNITS 1&2 - VOLUME I
6.22.2
Workshop compressed air system It is intended that the station instrument and general service air systems be piped into the workshop building. The Bidder may however propose a separate system for the workshop if the location of the workshop poses any difficulties in routing of the station compressed air supplies into the building.
6.22.3
Stores equipment The stores shall be fully fitted out for operational use. The Bidder may offer his own proposals but these shall include but not be limited to: A.
Steel racking for storage of materials and components.
B.
Steel racking and plastic bin system for storage of smaller parts.
C.
Propane powered stacking fork lift truck with capacity to reach highest storage racking.
D.
Outdoor Storage, Storeman’s Office, Substantial Shelving, (cannot be manufactured from re-bar or from scrap)
6.22-2 KHABAT TPP UNITS 1&2 - VOLUME I
6.23
General Plant Requirements The following requirements shall apply to all plant and equipment to be supplied under this Contract, unless specified otherwise in sections relating to specific items of equipment. For general requirements regarding inspection and testing, refer to Volume 2, Schedule G of this Specification.
6.23.1
Plant referencing
6.23.1.1 Plant referencing system The Bidder shall apply a plant coding/referencing system e.g. KKS (Kraftwerk Kennzeichen System) or other similarly internationally recognized numbering system for referencing of power equipment and systems. The Bidder and his subcontractors shall use the plant referencing system for numbering of equipment, piping, valves, cable, instrumentation and spares. Reference numbers listed on identification nameplates or tags shall be as per the approved plant referencing system. 6.23.1.2 Plant numbering/nomenclature guidelines In addition to the plant referencing system, plant and equipment items shall be identified by a nomenclature system; the following guidelines shall be used by all parties in determining the plant numbering/nomenclature: A.
the reference should be logical and simple
B.
each name should be unique
C.
there should be a differentiation between unit and non-unit names
D.
the names should be as short as possible
E.
the name should start with the major and proceed to the minor (in the case of feed heaters numbering shall be consecutive from the lowest pressure to the highest) the same name should consistently appear on all drawings, schedules and labels.
References shall follow a logical sequence based on layout or history and in any particular installation, a set of similar duty drives where any number of units may run, shall be suffixed 1, 2, 3 4 etc. whereas alternative drives for the same duty, where only one unit may run (i.e. duty/standby), shall be suffixed A, B, C etc.
6.23-1 KHABAT TPP UNITS 1&2 - VOLUME I
The Bidder shall also prepare a comprehensive Plant or Equipment Identification Schedule(s) using the plant reference system, which shall be updated and issued to KNOC every 6 months for the duration of the Contract. The Schedules shall include the Purchaser’s numbering system and the respective flow sheet or Diagram Identification Numbers. After final painting, all main plant items shall be identified by the reference characters. Such references to be affixed in a prominent position on the plant body with characters not less than 100 mm high or as otherwise specified. Characters shall be bold capital letters and/or Arabic numerals. The abbreviation ‘No.’ shall not be used 6.23.2
Nameplates and labels Instruction plates, nameplates and labels shall be provided for all items of the plant giving particulars of duty, size, serial number and full information for identification and operation. Nameplates shall be 3 mm thick laminated white, black, white traffolyte with lettering of a minimum height of 4 mm. Warning labels and emergency equipment shall have red lettering in place of the black. Warning and safety notices shall be in the English and Arabic languages. Labels shall be of sufficient size to carry a full description of the plant item and a unique item identification alpha-numeric. Abbreviations in the plant description shall only be used with prior approval of the KNOC. Valve labels shall be circular and fitted in the centre of the valve handwheel. All other labels shall be square or rectangular and shall be fitted by 3 mm stainless steel self-tapping screws or stainless steel banding as appropriate for the location. Labels shall be fitted such that they are not readily lost or broken during routine operation and maintenance. Any labels damaged or defaced during installation or plant start-up shall be replaced by the bidder prior to plant acceptance by the KNOC.
6.23.2.1 Pipe service identification A color banding scheme shall be used to identify pipe work. The identification requirements and colors employed shall be in accordance with the requirements of the relevant internationally recognized codes and standards. Color bands shall be painted on each side of all valves and equipment on the piping systems. The use of adhesive-backed color bands is not permitted. Valve labels shall be circular and fitted under the hand wheel captive nut. For 6.23-2 KHABAT TPP UNITS 1&2 - VOLUME I
check valves and small valves the Bidder may provide rectangular labels fitted to the valve or secured close by the valve. The inscription or “name” on each valve label shall summarize the duty of the valve, and the number shown on each valve label shall be the number in the unified plant valve numbering scheme. Where the direction of flow through a valve or other device is an important requirement for correct functioning, the body of the valve or device shall be legibly marked with a cast on or a properly secured arrow, showing the direction of flow. Pipe work shall be provided with plentiful large painted arrows and/or other secure and durable arrow markings to allow the flows of fluids around the plant to be readily understood. 6.23.3
Plant vibration Rotating Plant shall be designed and constructed to operate throughout its operating range without vibration insofar as the nature of the works will permit. In the case of rotating plant, vibration shall be reduced to the minimum, which can be achieved by good design, careful balancing and correct installation and alignment, as follows: A.
Rotating elements shall be balanced in accordance with the relevant grade of ISO 1940-1 as applicable.
B.
The vibration levels for the machinery covered by this Specification shall comply with the appropriate parts of ISO 10816 and ISO 7919 standards.
C.
Provision shall be made for the reduction of vibration transmitted to covers, cladding, platforms and structures that are liable to vibrate.
Refer to the relevant specification sections for vibration requirements for specific equipment, and to Section 8, Control and Instrumentation for details of vibration measurements. 6.23.4
Sunshades Outdoor plant shall be rated and constructed so that its performance, operation, reliability, maintenance, or life shall meet the specified design and operating conditions. Where personnel have to be in attendance frequently or maintenance has to be regularly carried out, permanent minimum weather protection or sunshades shall be provided. Facilities such as lighting, lifting beams and rainwater drainage shall be 6.23-3 KHABAT TPP UNITS 1&2 - VOLUME I
provided wherever necessary to the approval of KNOC as an integral part of the sunshade structure. 6.23.5
Special tools and tackle for maintenance The Bidder shall supply a complete set of any special tools and other equipment necessary for the dismantling, re-erection and adjustment of the plant. This shall include any special lift jigs, frames and stands necessary to remove and support the major items of plant. The tools provided shall be in new condition, adequately labelled as to their use and contained in stout and suitable padlocked boxes. The KNOC’s instructions as to who shall be the recipient of the tools shall be sought before delivery is made. Any special slings required shall be provided and clearly marked by embossed labels to show safe working loads. Test certificates shall be provided where applicable.
6.23.6
Locks and keys for mechanical plant Locks and keys for mechanical plant shall be of an approved dead latch type, or padlocks as appropriate. Three keys shall be supplied for each lock. Keys shall be unique to each lock. Where a set of locks is provided under any particular section of the Plant, a group master key shall be supplied in addition. All locks and padlocks shall be of brass and where they are fitted to switchboards or similar cubicles shall have the visible parts chromium plated. Where a group of locks is supplied under any part of the Contract, a rack or cabinet of approved design shall be supplied for the accommodation of all padlocks and/or keys while not in use. The padlocks and keys shall be engraved with an agreed identifying code or inscription and this shall be repeated on the racks or cabinets on engraved labels.
6.23.7
General mechanical requirements
6.23.7.1 General The Bidder shall be responsible for the detailed design and engineering of the plant and systems. The requirements specified herein shall form the minimum basis for the design and scope of work and working practices, manufacturing, testing and erection. 6.23-4 KHABAT TPP UNITS 1&2 - VOLUME I
Selection of materials, components, methods of construction and erection shall be made with due consideration to the requirements and capabilities of the equipment served, as well as the reaction and thermal, chemical, or other effects of the medium being handled by each system or component. Corrosion allowance for piping shall be 1.5 mm unless otherwise specified. The equipment, materials and services provided by the Bidder shall be consistent with the need to develop a safe, dependable, and adequate installation. The Bidder shall ensure that no individual element or system will set a limit on the station capability, or will disturb its architectural appearance when completed. 6.23.7.2
Pumps
6.23.7.2.1
General requirements
All pumps supplied within the Contract shall be designed, manufactured and tested in accordance with the requirements of the relevant Standards and Codes. Unless specified otherwise, centrifugal pumps shall be designed, manufactured and tested in accordance with the relevant internationally recognized codes and standards or equivalent internationally recognized standards. The pumps shall operate satisfactorily when delivering varying quantities from minimum up to the design maximum flow and shall be constructed to ensure continuity of service, ease of inspection, cleaning and repairs, together with satisfactory operation under all climatic conditions prevailing at site. Where duplicate pumps for the same service are provided they shall operate satisfactorily in parallel with each other. All pumps shall be designed far maximum continuous operation conditions even at system frequencies between +4% of rated frequency. All pumps shall have a design margin of 10% on flow and 20% on head. The characteristic curve of a centrifugal pump shall be stable under all conditions, i.e. the head shall increase with decrease in delivery until maximum head is reached at zero flow. Details of head and flow/performance characteristic curves shall be submitted for design review. The Net Positive Suction Head (NPSH) required at any capacity up to and including runout shall be at least 20% or 1 m less than the available NPSH, whichever creates the greater margin. The pumps shall be free from vibration at all load conditions and shall be designed to allow satisfactory and safe operation during all possible operating conditions, including cold and warm start-up and run out flow. 6.23-5 KHABAT TPP UNITS 1&2 - VOLUME I
The pumps shall be designed in such a way that no leakage shall result from a change in fluid temperature. In general mechanical sealing systems shall be used throughout. Material shall be specifically chosen to resist cavitation, erosion and corrosion, seizure or other destructive influences to which a pump may be subjected in service. If the pump impellers and the impeller shaft are of different material, any portion of the impeller shaft which could be in contact with the fluid must be covered by a sleeve of the same material as used in the impeller construction. The general arrangements of the pumps, motors, supports, piping etc. shall allow handling for maintenance with the least possible dismantling and joint breaking. All structures and foundations etc shall be designed, supplied, installed and tested under this Contract. This shall include steel wedges, levelling screws, support plates, foundation plates and anchor bolts, etc. All leakages shall be collected and directed to suitable drain connections and discharge system. Flexible coupling with guards shall withstand all service conditions and shall be arranged for easy disconnection and reassembly. Suitable connections for instruments, drain and vents shall be provided. 6.23.7.2.2
Types of pumps
Horizontal spindle pumps of the centrifugal type shall have fully balanced impellers and at least two bearings. The driving motors shall be mounted on an extension of the pump base plates. Base plates shall be provided with drip tray facilities and provision shall be made for drainage. All pumps shall be capable of reverse rotation up to 125% of rated speed due to back flow of fluid without causing damage to the pump, alternatively a reliable method of preventing reverse rotation shall be provided. For certain services, the pump may be installed in a tank of suitable material which forms a well from which the pumps takes its suction. Such tanks will normally be cast in concrete, with the discharge flange above the floor level. Only the mounting and discharge flange bolts will require removal to pull the pump. Portable sump pumps shall be of the heavy duty submersible self priming type, each complete with 10 meters of flexible hose, sealed-off electric motor and flexible power cable 20 meters long. The power cable/pump motor connection shall be completely waterproof when connected. All portable sump pumps 6.23-6 KHABAT TPP UNITS 1&2 - VOLUME I
shall be suitable for pumping dirty water which may be contaminated with fuel oil. All positive displacement pumps shall be of the horizontal screw or gear type. All positive displacement pumps shall be complete with electric motor driver, common baseplate, gear type flexible coupling and base mounted coupling guard, arranged for easy disconnection and reassembly and designed to withstand all service conditions. The pump/motor combination shall be nonoverloading at 125% of the normal system operating pressure at the maximum pumping viscosity value. Spacer type couplings shall be used if required to allow pump disassembly without moving the motor. All pumps shall be direct drive. Pumps of the rotary screw type shall have two (2) or three (3) rotors in accordance with manufacturer’s standard. Externally lubricated indexing gears and bearings shall be provided. 6.23.7.2.3
General construction requirements
Air release valves shall be fitted where necessary at suitable points on the pump casing. Each pump shall be fitted with isolating valves and pressure gauges to suction and discharge, and a non-return valve on the discharge line. The following requirements are applicable to all pumps unless specifically noted otherwise in the particular system subsection. A.
Casing
B.
Cast iron/cast steel/stainless steel casting for casing materials shall be used to suit the duty.
Connections between pump parts shall be doweled where necessary to assure proper alignment and fitted with gaskets of standard thickness and material selected for durability and compatibility with the pumped fluid. The pump casings shall be horizontally split to allow easy maintenance, and suitable means shall be provided for withdrawing the removable top half casing and impellers without disturbing any of the connecting pipes or valves. A.
Seals Shaft seals shall be of highest quality design and material. Ample room shall be provided for seal maintenance and/or replacement. Unless specified otherwise, mechanical seals shall be used exclusively. Precautions shall be taken to prevent seal leakage entering the bearing housings. 6.23-7 KHABAT TPP UNITS 1&2 - VOLUME I
B.
Bearings Antifriction type bearings shall be provided as required by the particular pumps specification. They shall be amply sized to carry all loads applied and shall be designed for 100,000 hour rated life under design conditions. Where bearings are of the ball or roller type the inner race shall be fitted directly to the shaft and shall be located at a raised machined shoulder of the shaft. Where the pumps are operated intermittently, special care shall be taken to prevent brinelling of the races while the pumps are not in operation. Intermediate shaft bearings for the suspended vertical type of pumps shall be securely connected to the main pump supporting tube. The weight of the pump impellers and shaft in addition to fluid axial forces shall not be taken by the motor bearings but by a separate thrust bearing for which ample access shall be provided for examination and maintenance. All bearings shall be oil tight against the atmosphere. Provision shall be made at each end of the bearing to prevent oil or grease being thrown off outside the bearing housing or creeping along the shaft. Bearings requiring cooling water shall be provided with all the necessary pipe work, valves and strainers for this purpose. All pumps shall have adequate thrust bearing provision.
C.
Shafts Impellers shall be mounted on shafts, keyed against rotation, and accurately positioned by collars or other suitable means. Shaft material shall be stainless steel 316 L unless specified otherwise.
D.
Impellers Impellers shall be accurately machined, statically and dynamically balanced to provide vibration-free operation. All surfaces shall be finished to a smooth contour. Impellers shall be of stainless steel 316 L unless otherwise specified.
E.
Couplings Each coupling half shall be keyed and properly fitted to it’s shaft. It shall be capable of absorbing variations in alignment and axial movements without affecting performance. It shall be adequately sealed to prevent entrance of sand or other foreign material. All couplings and any intermediate or dummy shafting shall be efficiently guarded. 6.23-8 KHABAT TPP UNITS 1&2 - VOLUME I
F.
Wear rings Renewable casing and impeller wear rings shall be furnished on all pumps and shall be of materials compatible with pump casing and impeller.
G. Workshop tests All pumps shall be workshop-tested in accordance with the relevant approved standard, as noted above. Pump performance curves, based on actual tests unless prototype tests are accepted, shall be submitted for each pump in the quantity and manner set forth elsewhere herein. 6.23.7.3 Tanks and pressure vessels Unless otherwise specified, tanks and pressure vessels shall be of welded construction, manufactured from carbon steel plate of accepted quality and thickness, and designed, constructed and tested in accordance with the appropriate API, AWWA and ASME standards as applicable. The tank supports - if any - shall be of such a height as to permit cleaning and painting of the floor plate of the tanks from the tank bottom. Tanks and vessels which are to be lagged shall be provided with external lugs for attaching reinforcement wire where necessary. Prior to the application of internal protection the tanks and vessels shall be thoroughly cleaned, dried by hot air or other approved means and shall then be
sandblasted
and
treated
internally
by
processes
as
specified.
Arrangements shall be made for the blanking off or removal of all valves or pipe connections during sand blasting to prevent the ingress of sand or other matter. The protective process shall be applied also to any ferrous fittings mounted inside the tanks. All tanks and pressure vessels shall be painted externally, in accordance with the specified provisions. All equipment shall be earthed and cathodically protected where appropriate. Corrosion allowance for pressure vessels and tanks shall be 3.0 mm unless otherwise specified. Tanks where appropriate shall be electrically isolated from cathodically protected pipe by insulating flanges or dielectric unions. 6.23.7.4
Bolts and nuts All bolts and nuts etc. shall conform to the stipulated standards. Bolts or studs which are subjected to high pressure and temperature shall be high tensile alloy steel with nuts of a suitable, approved material, and shall comply with ANSI requirements for power piping. 6.23-9 KHABAT TPP UNITS 1&2 - VOLUME I
All bolts or studs manufactured from alloy steels or steel shall be suitably machined at the shank and under the bolt head. Washers shall be provided under nuts, and also under bolt heads if required. 6.23.7.5
Thermal insulation
6.23.7.5.1
General requirements
Unless otherwise stated all pipework, ductwork, casings, flues and equipment that transmits or receives heat, or will form condensate shall be insulated with asbestos free materials. Heat insulation of all plant and pipe work having temperature of 65°C or more shall be provided to reduce the heat loss to atmosphere to a minimum, reduce the cooling load on the air-conditioning system, and to afford operational safety to the personnel. Where applicable the heat insulation shall be made of prefabricated formed lagging. Otherwise, insulation mats stitched on a mesh of galvanized wire shall be used. The insulation material shall consist of noncombustible and chemically inert material. The aim is to achieve an optimum reduction in heat loss by providing insulation of the appropriate type and thickness. Personnel protection insulation and protective covering shall he provided on piping and equipment where heat loss is inconsequential and where the surface temperature may exceed 60°C. All piping, valves and equipment which contain chilled water shall be covered with approved anti-sweat insulation, comprising a vapour resistant barrier jacket. Furthermore, the thickness shall be chosen in such a way that a heat loss of 230 watts/m2 is not exceeded. That calculation of thickness and thermal conductivity shall be subject to approval by the KNOC. All insulation shall be installed with proper allowance for expansion and insulation exposed to the weather shall be installed with proper flashing so as to keep the insulation dry at all times. The Bidder shall exercise extreme care in storing and applying insulation to make sure that it remains dry until water proofed. Insulation materials shall be stored in an enclosed area and shall always be stored in original containers until ready for application. Insulation that has become damp shall not be applied. Before applying the insulation, all piping vessels and equipment shall be 6.23-10 KHABAT TPP UNITS 1&2 - VOLUME I
tested for leaks and repaired, if necessary. Metal surfaces to be insulated shall be free from rust, grease, dirt, frost and moisture. Insulation shall not be applied to any vessel or equipment until all tests have been made, leaks repaired and tests accepted. Piping shall be covered with pre-formed half-cylindrical or curved segments of insulation materials. Insulation shall be applied with the circumferential joints staggered for single layers and with both the circumferential and longitudinal joints staggered for double layers. Each layer shall be securely wired. All joints of each layer and any voids or irregular surfaces shall be filled with insulating cement so that the surface will be cylindrical and smooth before the next layer or jacketing is applied. This principle shall be applied to every application. Covering on vertical runs of pipe shall be supported in such a manner as to prevent displacement due to slipping or contraction. This shall be accomplished without welding to pipes. Flange covers shall be made of sectional pipe covering or block insulation. These flange covers shall be made removable and to the thickness of the pipeline covering. Sufficient space next to flange shall be allowed for bolt removal. All valves and fittings shall be covered with insulating material of the same kind and thickness as that specified for the pipeline in which they are installed or by plastic insulating cements. The surface shall be coated with a vapour barrier cement or mastic and covered as appropriate. The final outer layer shall be aluminium cladding so as to be completely weatherproof. In the case of reducing fittings the largest pipe size shall determine the thickness of the material to be used. Insulation shall be removable. On equipment with regular surfaces such as tanks and vessels, calcium silicate blocks shall be applied. Layers shall be secured on the shells with stainless steel bands on 225 mm maximum centers machine stretched, and clamped in place under tension.
Where multilayer application is required, all
joints are to be staggered over joints of preceding layer. Heads of vessels are to be insulated with flat block insulation and secured with bands on 300 mm maximum centers attached to a double layer of circumferential bands or to rings welded to the vessels. Where removable head covers are required for exchanger head removal, the covers shall be field fabricated to allow access to these areas without disturbing adjacent insulation. Equipment insulation is to be covered with aluminium jacketing as specified for piping. Longitudinal 6.23-11 KHABAT TPP UNITS 1&2 - VOLUME I
and circumferential seams shall be lapped a minimum of 75 mm.
Insulation
shall be cut away from markings such as nameplates, clips, code inspection plates, etc, sealed and flashed against the entrance of water. Insulation and metal covers for manholes and blind flanges where required shall be twopiece removable covers. Skirts and supporting legs on equipment shall not be insulated. Longitudinal expansion of vessels shall be provided for by installing expansion joints. Nameplates on insulated equipment shall be removed and reinstalled by the Bidder on outside of covered surface in a secure manner satisfactory to the KNOC. Code stampings on pressure vessels shall be insulated with a removable section of insulation and lagging for easy accessibility for inspection. The Bidder shall furnish and install all insulation clips. All instrument connections on pipes, ducts, vessels or equipment shall be insulated. The insulation shall be shaped at these connections by tapering it to and around the connection with insulating and finishing cement. All access doors, removable panels, manhole covers and other parts on equipment requiring insulation, which must be opened or removed, shall be insulated. The method of insulating removable parts shall be such as to eliminate damage to the insulation on the removable part and on the adjacent surfaces. Edges and corners shall be protected by light structural angles or metal strips, and wire mesh shall be employed where necessary to hold the insulation securely and permanently in place. 6.23.7.5.2
Materials for heat insulation
The material used shall withstand the specified temperatures without deterioration shrinkage, change in form or pulverization. A.
Heat insulation Heat insulation materials shall be calcium-silicate in the form of flat or curved blocks for equipment and in the form of half-cylindrical or curved segments for piping. The materials shall meet the requirements of ASTMC533, Type I or equivalent. The use of preformed insulation materials shall be maximized when fabricating covers on valves, fittings, flanges, vessels, etc. The Bidder shall ensure a satisfactory fit on all piping and tube sizes to accommodate thermal expansion.
B.
Finishing cement If required finishing cement shall consist of asbestos free mineral fibre and suitable fillers premixed with a hydraulic setting binder. It shall be 6.23-12 KHABAT TPP UNITS 1&2 - VOLUME I
compatible with adjacent insulating materials and conform to ASTM-C449 or equivalent. When mixed with water, it shall form an easily workable plastic mix suitable for trowel application. After drying, it shall present a hard, smooth and durable surface free of cracks. C.
Wire-mesh and binding wire Wire mesh shall have hexagonal openings of 10-20 mm nominal size. It shall be woven of No 20 wire gauge from stainless steel wire. Binding wire shall be of stainless steel and not smaller than No 16 SWG.
D.
Aluminium for jacketing Aluminium sheets shall be of alloy type, resistant to seawater corrosion, medium hard. Embossed material with vapor barrier shall be used for cladding over thermal insulation with a minimum thickness of 1.2 mm.
E.
Mineral wool Mineral wool shall be used for loose insulation where use of prefabricated blocks is not possible. The mineral wool shall be stitched on one side to wire mesh by means of stainless steel wire. The material shall comply to the following specification: The mineral wool shall not contain any sulphur, or other corrosion causing materials i.e. it should be resistant to acid, hot water and steam. The mats shall have good resistance to shocks. The fiber of the mineral wool shall not be destroyed under the influence of long-term mechanical vibrations.
6.23.7.5.3
Frost protection (if applicable)
The plant shall be adequately protected against frost damage. Particular attention should be given to pipe work, pump casings, etc, and any part of the plant and equipment likely to stand for periods charged with static water. Water used in closed circuits shall be treated with an approved antifreeze compound. All water pipe work, pumps, valves, etc situated out of doors shall be protected against frost damage by thermostatically controlled electric trace heating and approved
weatherproof
insulation.
The
trace
heating
shall
energize
automatically when the ambient air temperature drops to 3°C and shall maintain the system at a temperature no lower than 3°C. The trace heating supply shall be energized at 110 V 50 Hz, centre point earthed, utilizing on approved proprietary system. The trace heating system shall be installed in sections such that failure of one section does not affect other sections of the heating system. Local panels 6.23-13 KHABAT TPP UNITS 1&2 - VOLUME I
shall indicate when each section of heating is energized and failure of any section such that the faulty section can be readily identified. An alarm shall be raised when a fault occurs and transmitted to the PCS system in the central control room. Insulation shall be suitable for outside installation and completely impervious to all weather and atmospheric conditions on the works. Lagging materials containing asbestos shall not be used. The lagging shall be sectional and easily removed for maintenance purposes. Joints shall be sealed together with an approved waterproof adhesive tape. 6.23.7.5.4
Finishes
Protective covering shall be applied to all heat, personnel protection, and antifreeze insulation. The materials for anti-sweat insulation shall be highly effective in preventing sweating and capable of satisfactorily withstanding moisture, and shall therefore not require additional protective covering. Metallic cladding and weather proofing shall be applied to all insulated surfaces where practicable. Longitudinal and circumferential joints for lagging shall be lapped to a minimum of 75 mm. Longitudinal laps shall be generally located on the horizontal centerline of horizontal runs of pipe.
The outer
part of the lap for all horizontal joints and circumferential joints in vertical runs of piping shall be turned downward in order to shed all water from the joint. Jackets shall be secured with stainless steel sheet metal piping screws on l00 mm centers on longitudinal joints. Elbows, bends and fittings shall be provided with cladding made from individual segments. The covering shall be furnished with neatly cut-off openings with separate sheets collars for the pipe hangers and other pipe connections/tappings. On bends, fittings valves and on equipment where a minimum overlap of aluminium is not possible, special workmanship such as beaded and crimped edges, shall be employed to produce a weatherproof covering. 6.23.7.5.5
Insulation for the boiler
Adequate cleats shall be provided together with wire netting reinforcement to ensure a satisfactory fixing of the insulation to all flues and ducts and other similar equipment. The boiler, superheater and economizer enclosure, and all gas ducts shall be insulated where possible by a preformed slab material. The casing finish shall be in galvanized mild steel or other stainless material sheeting and completely 6.23-14 KHABAT TPP UNITS 1&2 - VOLUME I
weathertight. Access doors in the ducts shall be insulated to a similar degree as the unit casings and flues which they serve. Insulation of doors shall be removable and replaceable to enable access to be gained without damage to the surrounding insulation. The insulation shall preferably be calcium silicate, mineral wool or other equivalent material and shall contain no asbestos such that cutting and forming operations will not present a health hazard. Refer to the General Mechanical Section for overall insulation requirements. 6.23.7.5.6
Insulation for the turbine
The insulation of the turbine shall contain no asbestos-derived materials. Cylinder insulation is to be by mineral wool with galvanized netting. The netting shall be covered by an impervious service. On areas to which access is required, such as valves, mattresses made of insulating material and enclosed in aluminium sheets may be used. All other hot areas, including hot drains piping shall be lagged and cleaded with metal cleading. All instrument root and drain valves to be external to the cleading. A soundproofed enclosure shall be supplied for the steam turbine if noise levels at any point 1 m distance from the set will exceed 85 dB(A). The enclosure shall have hinged access doors to enable routine inspections with adequate lighting system as required for routine inspection, completely wired with plugs and disconnects to allow for enclosure removal. Refer to General Mechanical Section for overall insulation requirements. 6.23.8
Steelwork All supporting steel structures shall be provided for plant, ducting, pipework and galleries, including pipe support brackets. All necessary platforms, toe-plates, ladders, stanchions, handrails, chains and all associated fittings shall be supplied to provide a safe and efficient installation. All mild steel items shall be protected by hot dip galvanizing after fabrication with a minimum thickness of 85 microns, unless otherwise specified. No cutting, drilling, bending, riveting, threading or similar operation will be permitted after galvanizing, and due care shall be exercised in transporting, handling and fixing galvanized metalwork to prevent damage to the zinc coating. Under no circumstances shall damage to the zinc coating be repaired with rust inhibiting paint. 6.23-15 KHABAT TPP UNITS 1&2 - VOLUME I
6.23.8.1
Platforms Platforms shall be constructed using galvanized open steel flooring to the relevant internationally recognized codes and shall cater for the relevant loadings for maintenance. The minimum acceptable size being 30 mm deep, 3 mm thick bars at 42 mm bar spacing. The flooring shall be bolted to the framework using approved bolted clips. The platform framework shall be galvanized. Platforms shall be provided and toe plates fitted to all platform edges. All platform panels shall be individually secured and be of suitable size and weight for ease of handling. Plated flooring shall be chequer plate having a minimum base thickness of 8 mm with a non-slip tread pattern, secured to the supporting steelwork with countersunk screws, which shall be cadmium plated. For manoeuvring smallwheeled items eg switchboard trucks, plain floor sheeting 8 mm minimum thickness shall be provided over specified areas. Open mesh platforms shall be open type, galvanized mild steel flooring suitable for a loading of 15 kN/m2 supported by heavy duty curbing giving a landing of 35 mm. Hinged grating with facilities for securing in the open position shall be provided as necessary.
6.23.8.2
Ladders and stairways Access ladders shall be provided as required. Step type ladders shall have flat section, non-slip, open type treads not less than 450 mm wide between stringers, with handrails fitted to each side extended to meet the platform handrails at the upper end. Vertical fixed ladders for emergency use shall be in accordance with the relevant internationally recognized codes and standards with equally spaced rungs between 230 and 260 mm apart with a width between stringers not exceeding 400 mm. Safety hoops shall be provided where necessary. Stairways shall be not less than 760 mm wide between stringers, and have an inclination to the horizontal not exceeding 40°. The stairways shall be constructed of galvanized mild steel stringers with galvanized open steel treads, reinforced at the leading edges, supported by substantial structural members. Galvanized handrails and standards shall be provided on each side of the stairway. 6.23-16 KHABAT TPP UNITS 1&2 - VOLUME I
6.23.8.3
Stanchions, handrails and chains Handrailing shall be 25 mm bore, with welded joints carried on solid forged steel handrail standards all galvanized with the upper rail not less than 1.1 m above the platform level. Ball type tubular standards are to support the handrails at not more than 1.5 m centers and arranged so that there is a standard not more than 300 mm away from any bend and 150 mm from any handrail joint. Handrails are to be secured to prevent movement within the standards. Stanchions and handrails shall be attached to the platform/walkway frame and not to any non-structural floor or toe-plates. Wherever possible, runs of handrail shall be continuous and sharp vertical changes of direction shall be avoided. Handrails shall terminate in swept ends either to the wall or return to the knee rail by means of a U bend which shall not extend greater than 350 mm beyond the centre line of the last standard. Entry points to ladders and platforms where necessary shall be protected by a double row of safety chains of mild steel 3 swg × 3 links per 100 mm complete with ‘S’ hook attachments.
6.23.8.4
Toe-plates All platform and walkway frames shall have toe-plates attached to the sides where handrails are fitted. Only around cut-outs provided in floor plates shall the toe-plate be secured the floor plate by welding. Toe-plates shall be at least 100 mm high and 5 mm thick and the gap between toe and floor plates shall not exceed 15 mm.
6.23.9
Safety guards for plant and apparatus Guards to ensure safety of personnel shall be provided to the approval of the KNOC and shall be generally in accordance with the relevant internationally recognized codes and standards.
6.23-17 KHABAT TPP UNITS 1&2 - VOLUME I
6.24
Painting and Protection Against Corrosion All material and equipment shall be effectively protected against corrosion during transit and while being stored at site. All materials and equipment shall be protected by the application of anti-corrosion agents in a mineral-oil base. This specification defines the requirements for painting, surface preparation, as well as the application of protective coatings for structural steel, equipment, piping, tanks, etc. for the entire plant.
6.24.1
General The Bidder shall, at all times, have access to the works in order to inspect surface preparation or application of work in progress in the workshop as well as on Site. Should any work or product be found to be defective or not in compliance with the specification, correction or replacement shall be made by the Bidder at his costs. The Bidder shall bear the full responsibility for the application of coatings, applied by him on surfaces, primed or painted by others. All coatings proposed for the internal protection of potable water tanks shall be certified by an approved independent institute. Covers should be used where required to protect building structures, equipment, insulation and lagging. When surfaces have been stained or otherwise damaged by the painting and/ or surface preparation work, the
Bidder is responsible to thoroughly clean and/ or repair these surfaces. Scaffolding shall be erected, maintained and dismantled without damage to equipment, piping, machinery or structures. Parts which cannot be coated and which are very sensitive to atmospheric exposure must be efficiently packed for storage. The inside of equipment and machinery shall be cleaned thoroughly at works, and before transportation all holes and access openings shall be efficiently sealed in order to prevent infiltration of dirt and humidity. Treated and machined parts not to be painted shall receive a provisional corrosion protection.
6.24-1 KHABAT TPP UNITS 1&2 - VOLUME I
Unless otherwise specifically indicated, surfaces, such as stainless steel, brass, copper or any other nonferrous items, finished hardware, aluminium windows, etc. shall not be painted. •
Exception : Gas turbines/generators and its auxiliaries shall be painted in accordance with the Bidder’s’ Standard.
•
Structural bolts shall be galvanised, sheradised or cadmium-plated and painted as specified under painting systems for carbon steel surfaces.
The method of application shall be to the approval of the KNOC and shall be taken to ensure mechanical and electrical compatibility with the factory applied coating and the cathodic protection system. The Bidder shall provide a full paint and coatings schedule to demonstrate the adequacy of the provision. The Bidder shall submit to the KNOC six (6) sample chips (100 × 150 mm size) of each colour and finish on the type of surface specified. Colours shall be indicated on the paint and coatings schedule. 6.24.2
Protective coatings and paint systems Type and number of protective coatings for any item which requires corrosion protection on this project shall be in accordance with the attached coating specification. The intention of the coating specification is to protect all parts which require corrosion protection with a prime coat which should be applied at Bidder's works. Only touch-up of bolts, welds and damaged areas will be required for field priming of these items. For parts which are not likely to be damaged during transportation, the KNOC may give the approval to apply the full number of coats for these parts in the shop.
6.24.3
Conditions for painting In general, coatings shall not be applied when the temperature of the steel is below +10 ℃. Surface temperature must be at least 3℃ above the dew point to ensure that condensation does not occur on the surface. In order to prevent condensation on the steel surface, the relative humidity must be checked continuously. The measurement of these conditions is under the Bidder’s responsibility. 6.24-2 KHABAT TPP UNITS 1&2 - VOLUME I
Coating materials should not be applied if the steel temperature is above +38 ℃. No coating should be executed during sand storms and rain. If more stringent, the manufacturers' recommendations shall supersede the above. Special exception for applications at higher or lower temperatures are possible if approved by the Coating Bidder and the KNOC at Site. 6.24.4
Safety precautions All necessary precautions shall be taken by the Bidder to protect personnel and property from hazards due to falls, injuries, toxic fumes, fires, explosion or other harm. All painting and corrosion protection work, including the inside of buildings and vessels, shall be performed under strict safety conditions. The Bidder is responsible for adequate ventilation, protection from open flames, sparks and excessive heat, by taking into consideration the high temperatures prevailing especially during summer. The areas where this work is performed shall be clearly marked with warning signboards. the Bidder is responsible to ensure that all work to be done and all equipment used is in accordance with the local authority regulations. The Bidder also has to follow the safety regulations of the relevant local or plant safety department.
6.24.5 Surface preparation All surfaces to be protected shall be coated in accordance with the requirements of ISO 12944: 1998. Preparation grade for surfaces shall be a minimum of Sa 2½. 6.24.6 Galvanizing Where employed, galvanizing of surfaces shall be in accordance with the requirements of ASTM A123/A123M-01a or equivalent. Bolt fixings shall be galvanized in accordance with the requirements of ASTM A153/A153M-01a. Preparation grade for surfaces shall be Sa 2½. Where the galvanized surface is rendered discontinuous for any reason, the un-galvanized surface shall be thoroughly cleaned to bright metal and painted to the requirements of ASTM A123/A123M-01a or equivalent.
6.24-3 KHABAT TPP UNITS 1&2 - VOLUME I
6.24.7 Painting All exterior surfaces, including buried and aboveground pipe work, shall be of high durability (>15 years) and appropriate to a C5-I (very high industry) or C5-M (very high marine) environment as appropriate. Interior surfaces shall be of be of high durability (>15 years) and appropriate to a C4 environment. High temperature and intumescent coatings shall be in accordance with manufacturers’ guidelines.
6.24-4 KHABAT TPP UNITS 1&2 - VOLUME I
6.25
Packing and Marking On Packages All apparatus shall be carefully packed for export shipment and storage at Site in such a manner that it is protected against all climatic conditions. All tubes and pipes shall be protected from external damage and to prevent ingress of dirt during transport and storage. The Bidder shall submit details for approval of the proposed methods of protecting the individual pipe ends before any pipes are dispatched to Site. Wood plugs shall not be used for sealing the ends of tubes. When tubes are to be stored on Site they shall be placed on supports so that they are not in contact with the ground. All bright parts liable to rust shall receive a coat of anti-rusting composition and shall be suitably protected. Special precautions shall be taken to protect journals where they rest on wooden or other supports likely to contain moisture. At such points wrappings shall be used impregnated with antirusting composition and of sufficient strength to resist chafing when subjected to the pressure and movement likely to occur in transit.
Motors and
equipment with ball or roller bearings shall be protected with resilient packing to prevent damage due to vibration. The packing cases and packing materials are included in the Contract and shall be the property of the KNOC. 6.25.1
Receipt and storage at site All items, packing cases, containers and packages received at Site shall be recorded against the shipping schedule and immediately inspected for signs of damage. All items are unpacked and inspected upon receipt including those with packing that is damaged. All signs of damage shall be investigated and the extent and nature of the damage recorded. The contents of each packing case, container or package shall be checked against the contents list and any discrepancies noted. Each item shall be carefully unpacked and checked for mechanical damage and/or damage to the corrosion protection. All such damage shall be recorded. No item will be accepted for storage on Site until all mechanical and/or corrosion protection damage has been notified and rectified to the KNOC’s satisfaction. It is emphasized in this respect that for damage which may affect the life or function of the component the Bidder must submit a full report to KNOC describing the consequences of the damage and the proposed rectification procedures. 6.25-1 KHABAT TPP UNITS 1&2 - VOLUME I
All plant and equipment to be stored out of doors shall be placed on timber or the equivalent so that it is out of contact with the ground and provided with adequate protection against weather. KNOC may, if he considers it necessary, instruct the Bidder to carry out a repair or special cleaning process on any item on which the protection has been ineffective and/or which has been subjected to adverse storage conditions. All items stored at Site shall be inspected on a regular basis and adequate records of inspection and corrosion protection rectification carried out shall be kept. All such records and the items in store will be subject to periodic audit and inspection by KNOC who may require additional work to be carried out to either restore the condition of the item or to ensure that deterioration does not occur. The cost of all recording, inspection and rectification shall be borne by the Bidder who is also responsible for any necessary insurance claims against shipper and/or other parties in respect of the damage to or loss of any item or component. On withdrawal from store, each item or component shall be prepared for erection by removal of temporary shipping and site storage protection. Immediately prior to erection, inspection shall be carried out to ensure that all such protection has been properly and completely removed as necessary unless the protection is to be used for additional protection during erection. All such ‘left on’ protectives must be removed prior to commissioning the plant unless with the specific approval of KNOC they will be removed during testing and/or commissioning without detriment to the plant or associated plant and equipment. All desiccants and vapor phase inhibitors must be removed prior to erection
even
though
semi-completed
systems
and/or
vessels
may
subsequently require reprotection by similar means to prevent deterioration during erection. The Bidder shall be held responsible for, and make good, all damage occurring due to improper preparation of goods for shipment or storage. 6.25.2
Erection mark All members comprising multipart assemblies, eg steel framework, piping installations, etc. shall be marked with distinguishing numbers and/or letters corresponding to those of the approved drawings or material lists. These erection marks, if impressed before painting or galvanizing, shall be clearly readable afterwards. Color banding to an approved code shall be employed to 6.25-2 KHABAT TPP UNITS 1&2 - VOLUME I
identify members of similar shape or type but of differing strengths or grades.
6.25-3 KHABAT TPP UNITS 1&2 - VOLUME I
6.26
Flue Gas Desulfurization System
6.26.1
System description The FGD system shall be designed throughout so as to insure continuous, safe and economical operation providing the maximum of reliability and without undue noise, vibration, unstability, unbalance, scaling, plugging, overheating, abrasion and corrosion. The FGD system shall be designed and guaranteed up to 115% gas volume (FGD design condition) compared to gas volume of BMCR that include the increase of excess air, air preheater leakage and etc. From the SOx's point of view, the FGD system shall be designed and guaranteed up to max. Shut down of one unit shall not affect the operation of the other unit. The FGD system shall be designed to keep the balance of gas flow through absorber and flue gas system under all operation conditions. The Bidder shall submit the CFD(computational Fluid Dynamics) result descriptions including gas flow velocity and pressure distributions under all operation conditions.
6.26.2
System design criteria
6.26.2.1 The FGD system shall be designed and guaranteed to perform all performance guarantees with the boiler burning residual oil, heavy fuel oil, light fuel oil and natural gas. But, the flue gas system requirements given in design guide shall be designed and guaranteed to perform with the measured max. gas flow rate. After award, at the time of FGD system design start, the Bidder shall measure and recheck the flue gas conditions on Bidder's own responsibility and design the FGD system to meet all performance guarantees required in this specification under any flue gas conditions. 6.26.2.2 One(l) absorber shall be furnished per unit. 6.26.2.3 The FGD system shall be designed to provide reliable service over the life of the plant. 6.26.2.4 The Bidder shall also meet any additional design considerations imposed at the various boiler load conditions. 6.26.2.5 The FGD system shall operate automatically over the load range. 6.26.2.6 The specific location of equipment and arrangement of the facilities is flexible within the general area shown and shall be located by the Bidder to minimize 6.26-1 KHABAT TPP UNITS 1&2 - VOLUME I
the unstability and unbalance of gas flow, and pressure losses, optimize operational costs and procedures, and allow maintenance access to all equipment. 6.26.2.7 The limestone slurry preparation system and gypsum dewatering system shall be designed as a common facility for Two(2) units. 6.26.2.8 The FGD waste water treatment system shall be capable of treating all FGD waste water discharged from the FGD system of Two(2) units. 6.26.3
Design and construction features
6.26.3.1 Absorber system A.
General description The process adopted for the FGD system supplied by the Bidder shall be the wet limestone-gypsum process with in-situ forced oxidation. In the absorption reaction process, the sulfur dioxide captured from the flue gas by the chemical reaction with calcium carbonate in the slurry shall be converted to calcium sulfite. The clean gas shall pass through the mist eliminators to remove entrained mist droplets and solids from the gas stream. Air is sparged into the slurry collected in the absorber reaction tank i.e. the absorber lower section, for in-situ oxidation of the calcium sulfite to calcium sulfate. For complete oxidation and good mixing, a sufficient number of agitators shall be provided to maintain solids suspension and good mixing within the reaction tanks. The gypsum slurry shall be bleed to the gypsum dewatering system. All mist eliminator washing water shall be used as make-up water to the absorber.
B.
Number of components and redundancy The Bidder shall provide main equipment including the following not be limited to:
6.26-2 KHABAT TPP UNITS 1&2 - VOLUME I
Number for one(1) unit
Number for two(2) units
One(1) lot
Two(2) lots
N + 1 sets (one set stand-by)
Two(2) * (N + 1) sets
N sets
Two(2) * N sets
One(1) lot
Tow(2) lots
E. M/E washing water tank
-
One(1) lot
F. M/E washing water pump
-
Items A. Absorber with internal B. Absorber recirculation pump C. Reaction tank agitators and drivers D. Mist eliminator including water washing subsystem
G. Gypsum bleed pump
Two(2) sets (one set stand-by)
H. Oxidation air blowers
-
Three(3) sets (One set stand-by) Four(4) sets (Two sets stand-by) Three(3) sets (One set stand-by)
One(1) lot
Tow(2) lots
Two(2) sets (One set stand-by) Two(2) sets (One set stand-by)
Four(4) sets (Two sets stand-by) Four(4) sets (Two sets stand-by)
L. Emergency storage tank with agitator
-
One(1) lot
M. Emergency storage pump
-
Two(2) sets (One set stand-by)
1 lot
2 lots
I. Absorber slurry sump agitator J. Absorber slurry sump pump K. Absorber density pump
N. Other equipment required for complete absorber & aux. system
C.
Absorbers 1) The type of the absorber shall be designed by the Bidder. Each absorber shall include all necessary internal components, supports and linings, in-situ forced oxidation facilities, integral reaction tank and agitators, and maintenance access doors. The type and number of SO2 removal stages shall be determined by the Bidder. The Bidder must submit the detail data for the approval. The Bidder shall provide a design for the absorber which has been demonstrated to operate successfully in similar electric power utility service. 2) The optimum design parameters in the absorber, such as pH level, L/G ratio, limestone stoichiometric ratio, gas velocity, oxidation ratio, 6.26-3 KHABAT TPP UNITS 1&2 - VOLUME I
pressure drop, gypsum super-saturation, slurry reaction tank retention time, suspended solids content, etc. shall be determined by the Bidder based on the design conditions in this specification, and shall be described in the Bidder's document. The design parameters shall be of a proven design. The design concept shall have been used in previously designed and currently successfully operating installations at the same or similar design conditions. The basis for the selection of these design parameters shall be submitted for the review. 3) The absorber shall be constructed to form a leakproof envelope. Welded joints shall be used wherever possible. Flanged and bolted joints shall be used only where necessary for maintenance. Any penetrations of the shell required for slurry spray headers, piping connections, or accessories, shall be sealed and made leakproof. 4) The absorber shall be designed for the maximum positive or negative pressure loads, whichever is more severe considering upset conditions caused by damper operation. The absorber shall be provided with over pressurization protection to prevent an inadvertent over pressurization. Over pressurization protection shall be provided by piping loop water seal or the KNOC approved equivalent. Make-up water to loop seal shall be provided automatically from the washing water system and shall re-establish the seal in the event of over pressurization. The loop shall be sized to relieve the maximum flow from all pressurizing sources while maintaining vessel pressure at level where no damage to the vessel or linings could occur, but in no case shall that pressure be above the vessel design pressure. The water seal shall be freezing protected. The absorber tower shall also be designed for piping forces and moments, wind and seismic loads, and all other loads imposed on the absorber. Bracing and reinforcement shall be adequate to prevent excessive deflection and vibration. Internal supports and mist eliminator section shall be designed to withstand the maximum flooded weight of the supported section or the weight of the supported section with scale build-up and deposits that may be experienced in the plant. 5) The absorber shall be designed to achieve the uniformity of gas flow distributions on the absorber inside under all operation conditions. If 6.26-4 KHABAT TPP UNITS 1&2 - VOLUME I
the serious variation of gas flow occurs on the absorber inside, the Bidder shall provide the means to overcome the problem. 6) The Bidder shall perform computational fluid dynamics(CFD) model study of GGH, absorber, ductwork and stack(if required) combination to assure that appropriate gas velocities and uniform distribution is achieved in the full- scale installation of FGD systems furnished under this specification. The CFD model study shall be performed, completed, reviewed and approved by the KNOC within three(3) months after contract so that the test results can be fully incorporated into the final GGH/absorber/duct design. The CFD modeling shall demonstrate that the scrubbed flue gas at the inlet face of the first stage mist eliminator shall have the following gas velocity/distribution characteristics : a) 85% of all individual gas velocity reading shall be within ±15% of the average gas velocity. b) All individual gas velocity reading shall be within ±25% of the average gas velocity. c) In addition, the scrubbed flue gas leaving the second stage mist eliminator shall have appropriate uniform distribution for proper operation of GGH. The Bidder shall submit to the KNOC for approval a copy of the proposed model study, methodology and standards at least four(4) week prior beginning the model study. 7) The absorber and internal shall be constructed of ASTM A240(6% Mo. Or equivalent). The CCT (Critical Crevice Temperature) range value shall be average value of the super austenitic stainless steel(6.0% Mo) value or more. The CCT value shall be tested in accordance with the ASTM G48, method B or D. The guaranteed CCT Value shall be submitted for approval. High wear areas shall be protected against erosion. Wet-dry zones of the absorber inlet shall be ASTM B 265(Grade 2) solid, ASTM B575(14.0% Mo.) solid or equivalent up to the expansion joint immediately upstream of the absorber tower. Tower exterior shall withstand the corrosive salt laden atmosphere of the project site. 8) All equipment exposed to hot flue gas shall be designed by the Bidder to withstand upset gas temperature excursions. Also, materials 6.26-5 KHABAT TPP UNITS 1&2 - VOLUME I
located in the wet gas path shall be protected from the temperature excursion by operation of the emergency quenching system. Outlet gas temperature from the emergency quenching system under the conditions of maximum temperature excursion shall be low enough to preclude damage to components located in the gas path. There shall be no damage whatever to any equipment as a result of these excursions. 9) The Bidder shall design and select the proper distance between the upper spray level and the bottom of the absorber mist eliminator. The absorber gas inlet shall be located sufficiently high enough to prevent splashing from the absorber reaction tank. The gas inlet shall be downward sloping to facilitate draining of all fluids. A means of preventing sprayed slurry from entering the gas inlet side shall be provided. 10) The absorber shall be designed to include side-hinged, bolted manholes/access doors to permit entry. A larger access door shall be provided for the reaction tank to permit entry of cleanout equipment and/or maintenance tools and personnel. 11) The Bidder shall provide viewpoints to permit on-line viewing of mist eliminator surfaces and other section needed for inspection of absorber internal. Each viewpoint shall be at least 500 mm diameter, be constructed of suitable material and have a manual washing system of the internal viewing surface. 12) The absorber reaction tank volume shall be adequately sized to provide sufficient retention time for limestone dissolution, oxidation of calcium sulfite to calcium sulfate(gypsum), desupersaturation of recycled scrubber liquid to minimize vessel scaling, and promote gypsum crystal growth. The tank shall be sized to provide a minimum retention time which conforms to the Bidder's standard, proven design based on actual operation experience of full-scale commercial FGD system installations. The absorber reaction tank shall be constructed such as ASTM A240(6.0% Mo.) soild or equivalent. 13) The Bidder shall provide a detailed justification for the selection of the absorber reaction tank retention time sizing and materials of construction. 6.26-6 KHABAT TPP UNITS 1&2 - VOLUME I
The location and number of agitators for each absorber reaction tank shall be determined to minimize solids deposition on the tank bottom and to prevent pump cavitation. The reaction tank bottom shall be designed to prevent accumulation of any slurry and for ease of cleanout. Motor driven knife gate drain valve at the absorber reaction tank bottom shall be provided to permit complete draining of the absorber reaction tank to absorber slurry sump. In addition, the absorber reaction tank shall be provided with a sloped floor to facilitate cleaning of residual solids and/or liquids as well as washing water. The absorber reaction tank shall be provided with an overflow pipe properly sealed and heat-traced if required. The overflow pipe shall be designed for ease of cleanout. The slurry overflowed from reaction tank shall be collected in the absorber slurry sump. 14) For in-situ forced oxidation, oxidation air shall be introduced to the absorber reaction tank. The oxidation air supply system shall be equipped with the oxidation air humidification facilities. The oxidation air supply pipeline shall be solid super austenitic stainless steel(6.0% Mo) or equivalent from the humidifier to inside of the absorber and A53 Gr.B or eq. for rest parts of the line. A part of oxidation air line shall be insulated for personnel protection. The oxidation air supply facilities shall be designed to avoid being plugged by settlement of slurry, and to facilitate cleanout. The oxidation air flowrate shall ensure that adequate mixing velocities are maintained within the absorber reaction tank to prevent dead spots and permit even distribution of air flow. 15) Each absorber shall be equipped with one(1) absorber automatic vent valve required for maintenance, clarification, and etc. The vent valve shall be designed for complete and rapid ventilation of absorber. D.
Absorber recirculation system 1) The absorber recirculation system shall consist of pumps, pipe work, spray headers and nozzles to provide intimate contact between the slurry and the flue gas to be cleaned. This system shall be designed to have a sufficient and necessary liquid to gas (L/G) ratio to reliably achieve the required performance without scaling of absorber internal 6.26-7 KHABAT TPP UNITS 1&2 - VOLUME I
surfaces. The Bidder shall design for the appropriate number of absorber recirculation pumps. Each absorber recirculation pump shall serve only one(1) spray level. No manifolding of recirculation pumps shall be permitted unless it is part of the Bidder's proven commercial design with operating FGD system. The absorber recirculation pumps shall be installed in the absorber recirculation pump room of absorber building. 2) The absorber recirculation pumps shall be equipped with auto isolation valve on each suction and discharge line. The Bidder shall provide the facilities(auto isolation valve) to prevent the leakage of flue gas or slurry to the discharge line during pump maintenance in the discharge line at an accessible location. The slurry recirculation line shall be equipped with auto-flushing system, and the Bidder shall determine the flushing procedure of absorber recirculation pump not to break the mechanical seal. 3) The Bidder shall design the arrangement of spray levels and nozzles such that the absorber cross-section is uniformly covered. The spray pattern shall have extensive overlap to ensure full coverage of the gas path, thus avoiding channeling. The Bidder shall clearly demonstrate exactly how this uniform slurry spray pattern is achieved. The Bidder shall submit the absorber spray droplet distribution. Internal spray header piping shall be corrosion and erosion resistant material on the internal and external surface such as alloy or FRP suitable for the intended service. External spray header piping shall be rubber lined carbon steel, duplex stainless steel, or equiv. Nozzle arrangement shall be designed to minimize and preferably avoid direct slurry impingement on internal surfaces, or absorber walls. 4) The absorber spray nozzles shall be designed to prevent scaling, plugging and thermal shock, and to ensure long term operation. Spray nozzles shall be constructed of ceramic material such as silicon carbide or stellite. 5) Spray nozzles shall be connected to the spray nozzle header by flanged connection or special quick disconnect clamps for easy installation and removal. Flanged sections shall be abrasion and
6.26-8 KHABAT TPP UNITS 1&2 - VOLUME I
corrosion resistant material suitable for intended service. Flange bolts shall be ASTM A240(6% Mo.) solid or equivalent. 6) The absorber recirculation pumps shall be of an appropriate design suitable for handling abrasive slurry and well proven in full-scale commercial operating wet limestone-gypsum FGD plants. Impeller tip speed shall be less than 25 m/sec. The absorber recirculation pumps shall be provided with lifting devices for installation and maintenance. 7) The operation of absorber recirculation pumps shall be interlocked with the reaction tank level and absorber start-up permission. Whenever a pump is stopped, it shall be automatically drained and flushed with make-up water. The time interval for flushing and draining shall be adjustable by the operator. 8) Regardless of how many absorber recirculation pumps are provided, at least one absorber recirculation pump shall be a standby for effective operation and maintenance under any operating conditions. The stand-by pump shall be automatically put into service when any operating pump fails in the automatic mode. All performance requirements and guarantees of FGD system must be met at least one pump/spray header in stand-by and regardless of stand-by spray header position. 9) The recirculation flow rate to the discharge of each absorber recirculation pump shall be monitored and recorded by utilizing electrical current flow to the pump motors. 10) The bearings of the absorber recirculation pump shall be provided with temperature measuring instruments with temp. transmitter which shall be alarmed and logged in control system. 11) The absorber recirculation pumps shall be started or stopped corresponding to the effective required L/G ratio to remove SOx in the untreated flue gas so that the desulfurization process can be economical. The Bidder shall provide the detailed explanation of each reaction conditions and performance curve of the absorber recirculation pump at the reaction conditions. E.
Mist eliminators 1) The absorber shall be equipped with multi-stage, multi-pass, chevron type mist eliminators. The mist eliminators shall be located 6.26-9 KHABAT TPP UNITS 1&2 - VOLUME I
downstream of the last absorber recycling slurry header section. All mist eliminators shall be washed with make-up water and shall be designed for minimum carryover, pressure drop and plugging. The mist eliminator shall be of the continuous vane arrangement. For first stage, hooks or pockets shall not be used. The total carryover mist content(including acidic mist) from final mist eliminator shall not exceed 100 mg/N㎥ dry gas. The particulate loading downstream of the mist eliminator section shall not exceed the particulate loading into the FGD System. Performance test of entrained mist shall be performed using recommended method by mist eliminator manufacturer. The Bidder shall submit the relation between mist size distribution inlet of mist eliminator and mist removal efficiency. 2) The mist eliminators shall be constructed in individual cells with integral supports holding the slats or blades together such that the cell can be removed intact. The individual cells shall be sized so that no more than two maintenance personnel can handle them manually for removal from the absorber vessel even if they are fully scaled or plugged. Each cell shall be capable of passing through the access doors for the mist eliminator section. The individual cells shall also be capable of being removed without replacing the adjacent cells. 3) The mist eliminators shall be constructed of materials capable of withstanding the chemical and thermal environment of the absorber module. They shall be capable of withstanding high pressure water lancing typically employed in manual cleanings. Alloy, FRP or polypropylene is considered acceptable. 4) The mist eliminators and support structure shall be capable of supporting the weight of maintenance personnel and equipment in addition to any scaling or plug of the mist eliminators without deformation. The mist eliminator and spray nozzle support structure shall be constructed of solid super austenitic stainless steel(6.0% Mo) or equivalent which is the same material of absorber. 5) The actual average gas velocity through each mist eliminator part with vertical gas flow shall not exceed 4m/sec at design condition(115% BMCR Condition). The actual average gas velocity
6.26-10 KHABAT TPP UNITS 1&2 - VOLUME I
through each mist eliminator with horizontal gas flow shall not exceed 7m/sec at design condition(115% BMCR Condition). 6) For the absorber, the distance between two mist eliminators shall be no less than 1.5m. The cross-section of the tower or duct after the last mist eliminator shall not reduce in cross-section for at least 2.0 m. 7) The mist eliminator washing nozzles shall be connected to separate washing water supply headers for different areas of the mist eliminator. An automatic isolation valve shall be located on each header just outside the absorber module to allow independent operation of each header. The pressure of the washing water shall be monitored and adjusted in the supply line just before the header connection. The washing headers shall be designed such that the pressure of each nozzle shall be operated within ±10 percent of the average washing water pressure. Washing headers and nozzles should be of alloy, FRP or PP. Sufficient nozzles shall be supplied to provide at least 50 percent spray overlap coverage. 8) The mist eliminators shall be automatically washed on-line. The controlling system for the automatic mist eliminator washing sequence, duration, and frequency shall be capable of being easily reprogrammed. Washing procedure shall be not to occur the mist carry-over. Also, provision shall be made allowing the operator to manually initiate or interrupt the sequence. 9) The front and back side of each stage mist eliminator shall be provided with washing header and nozzles. The backside washing header of the second stage mist eliminators will be used at low or no load conditions. 10) The mist eliminator shall be capable of operating for at least 12 months without an increase pressure drop of more than 20% above the pressure drop measured during clean operation. The Bidder shall provide pressure taps and transmitters at the absorber inlet, just upstream of the first stage mist eliminators, and after the last stage mist eliminators. Pressure taps shall be provided with a method for cleaning without removal of the transmitters and associated equipment. The Bidder shall provide a differential pressure transmitter each mist eliminator.
6.26-11 KHABAT TPP UNITS 1&2 - VOLUME I
11) Test ports shall be provided downstream of the last mist eliminator to enable performance testing. Test ports shall be located at a minimum of eight equally spaced locations around the absorber circumference for vertical flow mist eliminators. Test ports for horizontal flow mist eliminators shall be located at locations acceptable to the KNOC. 12) The Bidder shall provide the mist eliminator washing system. The Bidder shall furnish one(1) mist eliminator washing water tank and 50% × 3 washing water pumps for two(2) units. F.
Gypsum bleed pumps 1) The Bidder shall provide two(2) gypsum bleed pumps per absorber, one is in service and the other is in stand-by for the full range of fuel sulfur content and boiler load. The main purpose of the gypsum bleed pump is to bleed off gypsum slurry from the absorber reaction tank to the gypsum dewatering system. Also, the gypsum bleed pump may be used to bleed chloride from the absorber tank. The gypsum bleed pump shall be designed to ensure the required performance without any disturbance of the SOx absorption and gypsum dewatering. 2) The operation mode of gypsum bleed pumps shall be determined by the Bidder and shall be designed so that the entire FGD system shall not be adversely effected by varying of the inlet SOx, Cl and particulate matter content in flue gas and the boiler loads. The amount of gypsum bleed shall be controlled by solid density of absorber recirculation slurry. 3) The gypsum bleed pumps will transfer slurry from each absorber to one(1) gypsum dewatering feed tank for two(2) units common use. Either continuous or batch transfer of the gypsum slurry bleed is acceptable providing there is no adverse impact on the performance of the Bidder's FGD system. The gypsum bleed system shall be equipped with auto-flushing system. A. Impeller tip speed of gypsum bleed pumps shall be less than 30m/s.
G. Oxidation air system 1) The oxidation air package shall consist of blowers, electric motors, lubrication systems with cooler, humidifier, distribution piping, absorber internal distribution system, isolation valves, associated 6.26-12 KHABAT TPP UNITS 1&2 - VOLUME I
instrumentation and controls and all required accessories to supply a fully functional system. 2) Oxidation air blower shall be of a single stage centrifugal type and shall provide oil free air. The bearing type of oxidation air blower is sleeve bearing with forced oil lubrication system or air bearing without oil system. The flow control method of oxidation air blower is inlet vane or outlet vane with actuator. 3) Humidifier shall be provided to pre-saturate the oxidation air. The spray water from the humidifier shall not flow into oxidation air blower. 4) The blower system and its associated enclosure shall be designed to the limit noise level. 5) Each blower of forced oil lubrication type shall be supplied with a complete lubrication system to supply oil at suitable pressures and temperatures to the blower and driver bearings, gears and couplings, as applicable. Provision in the lubrication system shall be made to allow the unit to shutdown and achieve a full stop condition without bearing damage in the event of lubrication system failure. Reservoir fill openings shall be equipped with a strainer. In addition, the reservoir shall be provided with an oil level indicator and sufficient degasification capability with adequate vent and a breather filter. 6) The water or oil cooler, if required, shall be a removable bundle shell and tube type arranged for maximum maintenance access without disturbing piping connections. Coolers shall meet the requirements of ASME Section Ⅷ, Division 1 and TEMA Class R heat exchangers and should be code stamped if required. Coolers shall be constructed of stainless steel. 7) The impeller may be made of aluminum-forged alloy or equivalent. After the final machining, the impeller and gear assembly shall be dynamically balanced in the manufacturer's plant. The rotor assembly shall be designed so that its design resonant speed is less than operating speed. 8) The bearing of the oxidation air blowers shall be provided with temperature measuring instruments with temp. transmitter which shall be alarmed and logged in the control system. The instrument shall be installed to proper area around the bearing. 6.26-13 KHABAT TPP UNITS 1&2 - VOLUME I
9) Gear casing shall have one smooth flat surfaces tapped to permit the installation of vibration probes provided by the Bidder. And the blower of air bearing shall have one vibration probe to get the axial movement. H.
Wastes and drainage transfer system 1) Drainage and flush water from pumps, piping and other FGD system facilities along with washing down water in FGD system shall be collected in the absorber slurry sump through pipes or trenches. 2) The collected slurry in the absorber slurry sump shall be returned to the absorber reaction tanks utilizing absorber slurry sump pumps furnished by the Bidder. 3) The absorber slurry shall be drained into the piping system through the absorber drain line. The absorber slurry sump pumps shall then transfer the slurry to the emergency storage tank. 4) The Bidder shall provide two(2) 100% capacity absorber slurry sump pumps for one(1) absorber. The absorber slurry sump pump shall be designed with sufficient capacity to pump the entire contents of the absorber reaction tank into the emergency storage tank within eight(8) hours.
I.
Emergency storage tank and transfer system 1) When it is necessary to empty the absorber, the absorber slurry will be drained to the emergency storage tank. The absorber slurry shall be transferred two ways. a) Utilizing the absorber slurry sump pumps b) Utilizing the gypsum bleed pumps. 2) The Bidder shall furnish one(1) emergency storage tank to serve two(2) units. 3) The emergency storage tank shall be equipped with two(2) 100% duty emergency storage pumps to reclaim the collected slurry from the emergency storage tank to each absorber reaction tank. In addition, the emergency storage pumps shall be able to feed the slurry collected in the emergency storage tank to the gypsum dewatering system for processing.
6.26-14 KHABAT TPP UNITS 1&2 - VOLUME I
4) The emergency storage pumps shall be sized to return, within eight(8) hours, the absorbent slurry to the absorber reaction tanks. 5) The emergency storage tank shall be constructed of carbon steel plate with a suitable corrosion/erosion resistant lining. The emergency storage tank shall be designed and constructed to drain the slurry completely. 6) The emergency storage transfer system shall be equipped with autoflushing system. J.
Absorber off-load cleaning system The absorber internals may be cleaned during normal unit maintenance outages. The absorber will be cleaned by the mist eliminator washing water and/or the make-up water from the mist eliminator washing header. The make-up water may be utilized to clean the spray headers manually by flexible hose connected from the mist eliminator-washing header by quick coupling connection. The Bidder shall provide one(1) quick coupling connection at the ground level, absorber inlet duct and mist eliminator washing spray header level for make-up water.
6.26.3.2 Flue gas system A.
General description Flue gas from the one(1) boiler will be transferred to one(1) GGH (untreated side) by means of two(2) CID fans located upstream of GGH. The flue gas will then enter the absorber where SOx is removed. And then, from absorber, treated flue gas will flow via the GGH treated side to the stack. The Bidder shall design a optimum flue gas system and absorber & aux. system in order to minimize the pressure drop across the whole FGD system, and provide the optimum and accurate gas pressure condition. The Bidder shall design and furnish all ductwork required. The ductwork shall be complete with expansion joints, access doors, flanges, insulation, lining, supports and hangers.
B.
Components The FGD flue gas system for each unit shall be composed of, but not be limited to the following :
6.26-15 KHABAT TPP UNITS 1&2 - VOLUME I
1) One(1) gas-gas-heater (GGH) 2) Flue gas ductwork 3) Expansion joints as required to allow for differential thermal expansion 4) Isolation dampers at FGD inlet duct 5) Isolation damper at FGD outlet duct 6) Isolation dampers at emergency bypass flue gas duct 7) Emergency quenching system 8) GGH washing water sump pumps & agitator 9) Purge air fan C.
Gas gas heater(GGH) 1) Flue gas treated by the absorber system shall be reheated to prevent visible plume and corrosion of duct and stack and to improve the diffusion efficiency into the atmosphere. The GGH shall be capable of reheating the treated flue gas temperature to 90℃ or higher at the stack inlet without supplemental heat input, based on MGR load. The GGH shall be designed and constructed for operation under all flue gas conditions and designed to provide the specified duty during all modes of operation including on-line mist eliminator washing. 2) For one(1) unit, one (100% x 1) rotation type regenerative counter flow GGH, that are vertical shaft, bi-sector rotary regenerative type, shall be furnished. 3) The GGH must be fabricated of materials proven to be resistant to the corrosive environment within the FGD system, and be suitable for emergency gas temperature excursions. a) The basket, rotor structures and untreated gas inlet connection duct shall be constructed of low alloy corrosion resistant steel plates (ASTM A588 or DIN equiv.), with a 50% increase in thickness for corrosion allowance. The rotor housing, both side outlet and treated gas inlet connection ducts shall be carbon steel plates with minimum thickness of 2 mm flake glass lining. b) The heat transfer element, not less than 1.2 mm total thickness, shall be made of low carbon steel covered with porcelain coating enamel or equiv.
6.26-16 KHABAT TPP UNITS 1&2 - VOLUME I
c) The radial, axial and by-pass seals, the face of sealing plates, retractable cleaning equipment and sealing plate adjusting mechanisms shall be fabricated from ASTM B575(14.0% Mo.) or equiv. 4) The GGH shall include, but not be limited to, the following main equipment a) Heat transfer surface b) Rotor drive The primary rotor driving mechanism shall consist of a drive motors, coupling, speed reducer and pinion gear. An auxiliary air drive system shall be supplied with the GGH and start automatically upon failure of the main drive motor, or remote manually or locally. The GGH rotor shall be supported at the bottom by a self-aligning thrust bearing assembly and guided at the top by a spherical roller bearing assembly. Both bearing assemblies shall be lubricated by oil baths or grease, and equipped with a complete shop assembled oil or grease lubrication system with oil level/temperature gauges. Water cooling shall be incorporated in the guide bearing oil circulation system to maintain proper oil temperature. c) Two stationary water washing devices Each stationary water washing device shall consist of a straight pipe with spray nozzles spaced to distribute washing water evenly over the heat transfer surface. These devices shall be used only for off-line washing. The pipes shall be located, one each, in the untreated gas inlet and outlet ducts integral with the GGH. d) Retractable cleaning devices Two combination, retractable cleaning devices located, one each, in the untreated gas inlet and outlet ducts integral with the GGH shall be supplied. The devices shall be for both regular soot blowing and on-line water washing. Each device shall consist of a single, retractable lance and drive mechanism equipped with separate steam and water nozzles, and limit switches to signal end of travel in both directions. The swivel and rotary retractable cleaning device is not acceptable. The Bidder shall provide two(2) high pressure wash 6.26-17 KHABAT TPP UNITS 1&2 - VOLUME I
water pump for two(2) units. The material of the GGH soot blowing and on-line/off-line washing nozzles, lances and connectors shall be constructed of ASTM B575(14.0% Mo.) or equivalent. -
On-line water washing system Material of on-line washing pipe shall be STS316 or higher.
-
Soot blowing system
An automatic soot blowing system shall be sequentially selective, retractable and furnished complete with all components for adequate operation.
If the supplied steam conditions are not suitable for GGH cleaning, the Bidder shall furnish the necessary means to attain the required steam pressure and enthalpy at all soot blowers. The Bidder shall furnish the electric heater to increase the steam enthalpy during low load.
The soot blowing system shall be equipped with equipment to prevent nozzle plugging and fouling.
The soot blowing steam line diameter shall be suitably determined to prevent from
excess
warming-up and
deterioration of steam quality. e) Scavenging system The material of fan and duct associated with scavenging fan shall be constructed of duplex stainless steel. The Bidder shall provide equipment to prevent opposite rotation when the scavenging fan is trouble during the FGD system operation time. -
Hot end leakage control system
-
Rotor Stoppage Alarm
5) Casings shall be furnished with provision to absorb differential expansion between the casing and rotor, and be fabricated of welded construction, properly ribbed and stiffened to prevent reverberation and amplification of vibrations. This may include, but not necessarily be limited to, both sliding bearing plate as well as any guidance structures required. 6) The maximum GGH leakage shall be less than two(2) percent of the gas flow entering the GGH at all load specified herein without operating of scavenging fan. 6.26-18 KHABAT TPP UNITS 1&2 - VOLUME I
7) Access for replacement purposes of all GGH baskets shall be provided. Suitable beams, lifting hoists and monorails, which shall be permanently installed, shall be provided for basket replacement. 8) Access doors shall be gas-tight when closed and shall be of adequate size for inspection, cleaning, and replacement of parts. The Bidder shall also furnish grating type walkways as required for maintenance and inspection of heating element and other internal. 9) A properly sized and designed drainage system complete with sampling points, valves and piping shall be provided under GGH hoppers. The Bidder shall design and supply a system to smoothly divert the ash collected in GGH hoppers and the washing water drained from GGH to the GGH washing water sump. D.
Ductwork 1) The Bidder shall provide all necessary flue gas ductworks, breeching, plenums, sampling connections, washing down and dropout hoppers, expansion joints, splitter plates/turning/guide vanes, gaskets/bolting materials, and access facilities for the scope of duct supply. 2) The superficial velocity of gas in the ductwork shall not exceed 20 m/sec at any location at the FGD design condition(115% BMGR Condition). Gas ducts shall be provided with suitable sampling connections. The test connections shall be located so as to be easily accessible and shall be provided with suitable caps to seal them when not in use. 3) Each duct described herein shall be constructed of the following materials or the approved equivalent. Materials Duct Zone
Plate / Thickness
Clad Material/ Thickness Clad
FGD Inlet Damper to GGH Inlet (Untreated Gas)
CRLS or EQ / 6mm
N/A
GGH Outlet to Absorber Inlet
SS400 or EQ / 6mm
Nickel-Base Alloy(14% Mo) or EQ. / 1.6mm
SS400 or EQ.
Wet Dry Zone
Nickel-Base Alloy(14% Mo) or EQ. / 6mm
N/A
SS400 or EQ.
Stiffener
Inner Stay
SS400 or A588 or EQ EQ / 6mm / 6mm Nickel-Base Alloy (14% Mo)or EQ. Nickel-Base Alloy (14% Mo)or EQ.
6.26-19 KHABAT TPP UNITS 1&2 - VOLUME I
Absorber Outlet to GGH Inlet (Treated Gas)
SS400 or EQ / 6mm
Nickel-Base Alloy(14% Mo) or EQ. / 1.6mm
SS400 or EQ.
GGH Outlet (Treated Gas) to FGD Outlet
SS400 or EQ / 6mm
Nickel-Base Alloy(14% Mo) or EQ. / 1.6mm
SS400 or EQ.
Nickel-Base Alloy (14% Mo)or EQ. Nickel-Base Alloy (14% Mo) or EQ.
All ductwork shall be designed to withstand the flue gas high temperature and pressure excursion situation. 4) Gas duct shall be furnished with supports to carry weight of duct, insulation, dust on the bottom, and vertical live load on horizontal projection of roof surface of 250 kg/㎡(outdoor duct). Ducts shall have a minimum thickness of 6 mm including a minimum of 1.6 mm for corrosion allowance. Gas duct shall be reinforced with stiffener having a minimum thickness of 6 mm. All duct internal material shall be constructed of the same material as the connected duct. Access doors shall be located at inspection point and area where access for maintenance is required. Doors shall have all necessary safety equipment such as stair and handrails. Access doors shall be fabricated of steel plate with positive closing mechanism, gas and airtight. Minimum size opening shall not be less than 500mm on vertical and horizontal axis. Steel plates bolted over access openings are not acceptable. 5) All plates to be field welded shall be shop-beveled or otherwise prepared so that the field welding may be done without additional field preparation. Clips shall be shop-welded to each section to facilitate alignment of the plates during field welding. 6) Abrupt turns with a radius with a less than five(5) diameters shall be avoided, but if such turns are required, guide vanes shall be provided. Guide vane shall be not thinner than 3 mm, spaced to minimize draft loss, suitably welded, supported, and reinforced. Distribution plates and other corrective devices, such as teardrop vanes, shall be incorporated as required on duct transition pieces. 7) Permanent scaffold brackets shall be provided where required for maintenance. Access platforms shall be provided at all hopper outlets. 6.26-20 KHABAT TPP UNITS 1&2 - VOLUME I
8) The drain piping and its valves shall be arranged at suitable locations on the flue gas duct for draining any condensate from the ducts. Drain piping materials shall be corrosion and acid resistant with the same property of the related duct plates. Especially, the Bidder shall consider the proper drain facilities for absorber outlet horizontal duct. Drains shall be collected in the GGH washing water sump. E.
Expansion joints 1) All expansion joints shall be of nonmetallic flexible belt type of gas tight construction and belt material shall be viton or equivalent. The belt and frame/bolt materials shall withstand the appropriate temperature and pressure associated with the design conditions specified and the appropriate safety margins without damage and shall be corrosion and abrasion resistant and non-vibration. 2) Expansion joints located at the interface with other equipment such as dampers and fans, or at the limit of the FGDs scope of supply shall have bolted flanges for the interface connection. Expansion joints adjacent to dampers shall have adequate clearance to preclude interference with damper moving parts. 3) Expansion joint belt material shop tests shall be conducted at the time of manufacture, and the test results shall be submitted to the KNOC for approval prior to delivery of the expansion joints. 4) Expansion joint flange materials shall be constructed of the same materials as the connected duct materials. Expansion joint flanges shall be insulated and lagged. 5) Expansion joints located in horizontal duct runs which are exposed to wet flue gas shall be provided with drains molded into the expansion joint belt material. Drain fittings shall be fabricated of FRP or the approved equivalent.
6.26-21 KHABAT TPP UNITS 1&2 - VOLUME I
F.
Dampers 1) All necessary dampers for equipment isolation and flow rate control shall be furnished by the Bidder for each FGD system. All dampers for flue gas shall be installed in a horizontal duct. 2) The damper assembly shall be designed to withstand the flue gas temperature excursions and pressure excursion situation (Min. CID Fan Test Block Pressure) without damage, binding, warping or leakage. 3) Limit switches shall be provided with all dampers to indicate fully open and fully closed positions. These limit switches shall be independent of those provided with the drive units (Limit switches and other damper I & C components shall have protection provision). 4) Electrical equipment that will be exposed to outside ambient conditions shall be housed. 5) Provision shall be provided to allow manual locking of the damper blade in the open and closed positions by the Bidder. The damper operator shall be equipped with a handwheel for manual operation. 6) Dampers in wet or low temperature flue gas shall be provided with drains. 7) The damper frame shall be designed to support damper actuators, seal air systems and other auxiliary equipment. The structural design of the damper frame shall be capable of withstanding a minimum of full actuator stall torque. 8) The damper operator shall have a rated torque output of not less than 300 percent of all combined dead and live loads at the maximum differential pressure across the closed damper under any operational condition. 9) Specific requirements for the isolation damper a) The Bidder shall provide the double multi-louver or tandem dampers per unit as the follows. -
Emergency bypass dampers for the full flue gas bypassing at emergency situation.
-
FGD inlet dampers in FGD inlet ducts.
-
FGD outlet damper for isolation of FGD system
b) Especially, the emergency damper shall be double multi-louver type. 6.26-22 KHABAT TPP UNITS 1&2 - VOLUME I
c) The emergency damper’s full close to full open time shall not exceed 10 seconds. When emergency damper is closed, the flue gas stream in power plant and FGD system shall be not affected by the pressure change. 10) The emergency damper shall be opened and the other isolation dampers shall be closed, whenever following conditions happen: a) Electric power failure b) Boiler master fuel trip c) CID fan trip d) Emergency quenching system start e) Too high temperature at the FGD inlet f) Too high or too low pressure at the FGD inlet g) Other conditions, the Bidder deems necessarily in order to ensure a safe operation Trip of single CID fan will open associated emergency damper and close isolation dampers. The other fan will continue operate. 11) The FGD dampers shall be constructed of the following materials or equivalent. Description
Emergency Damper
Internal Frame
Blade
Seal
ASTM B575 Up(14.0% Mo.), ASTM ASTM A588 or equiv. ASTM A588 or equiv. stream B265(Grade 2) or equiv.
Emergency DownDamper stream FGD inlet damper
FGD outlet damper
ASTM B575 (14.0% Mo.), ASTM B265(Grade 2) or equiv.
ASTM B575 (14.0% Mo.), ASTM B265(Grade 2) or equiv.
ASTM B575 (14.0% Mo.), ASTM B265(Grade 2) or equiv..
ASTM B575 (14.0% Mo.), ASTM ASTM A588 or equiv. ASTM A588 or equiv. B265(Grade 2) or equiv. ASTM B575 (14.0% Mo.), ASTM B265(Grade 2) or equiv.
ASTM B575 (14.0% Mo.), ASTM B265(Grade 2) or equiv.
ASTM B575 (14.0% Mo.), ASTM B265(Grade 2) or equiv.
12) The combined axial compression and bending stress shall not exceed 60 percent of yield at design conditions.
6.26-23 KHABAT TPP UNITS 1&2 - VOLUME I
13) Maximum blade deflection at the center of the span shall not exceed dimension of the blade divided by 360(L/360). Louvers shall overlap by a minimum of 14 mm to provide a positive stop to prevent over travel of the damper louvers. 14) Isolation dampers shall be provided with edge seals in addition to the frame seals. Seals shall be properly formed to insure proper sealing when the blades deflect under the differential pressure. Seal shall be bolted to the louvers for easy removal. Bolts, washers and nuts shall be constructed of 317LM stainless steel. 15) All dampers shall be designed for a fail-safe condition. This position, open, closed or in-place will be determined during detail design. 16) Seal air system a) Seal air system of all dampers shall be designed to prevent condensation and provide zero-leakage of flue gas across the damper. Seal air system also shall provide 100% isolation of flue gas from ductwork during non-operation of the seal air with corrosion resistance material. b) Each seal air fan and motor shall be sized to provide the following : -
The design flow shall be two(2) times the expected operating flow. The air heating capacity of each seal air heater shall be designed to maintain the proper range of seal air operating temperature at design flow.
-
The steam shall be used as the heating medium for the seal air heater of dampers. If the supplied steam conditions are not suitable for heating, necessary means to attain the required steam pressure and temperature at all heaters shall be provided by the Bidder.
-
For the design flow, the seal air fan shall be capable of maintaining at least an 80 mmH2O differential pressure between each seal air chamber and the flue gas pressure.
G. Emergency quenching system 1) The inlet duct of each GGH shall be equipped with an automatic emergency quenching system to automatically protect the GGH and absorber from gas temperature excursion during an air preheater
6.26-24 KHABAT TPP UNITS 1&2 - VOLUME I
failure or loss of normal liquid flow to the slurry recycle spray system or loss of electric power to the FGD system. 2) The emergency quenching system shall be designed and fabricated to provide quenching water at an adequate flow and pressure to lower the temperature of the flue gas entering the absorber to a level which will not cause physical deterioration or decrease service life of the FGD module. Quenching system shall be designed of materials suitable for the operating conditions experienced in the GGH inlet. Pipes, nozzles and headers shall be of a non-plugging type and duplex SS or equivalent. After emergency quenching, remaining water shall be fully drained to GGH washing water sump via the GGH wash drain line without inflow to the CID fan. The drain line shall be fully submerged in order to prevent the gas leakage. 3) Initiation of the emergency quenching system shall be alarmed. H.
Purge air fan 1) The Bidder shall provide one(1) purge air fan for each absorber, which ensure for man-safe entry, maintenance, etc. The purge air fan shall use non-leakage type valve or duct to prevent the gas leakage. 2) Each absorber shall be equipped with one(1) purge air fan required for man-safe entry, maintenance, clarification, etc. This purge air fan shall be selected in accordance with the requirements for welding in confined spaces, as contained in NFPA51 and NFPA51B and the OSHA requirement or equivalent. The purge fan shall be sized to permit personal entry within one(1) hour after an absorber is removed from service.
I.
Wastewater and drainage transfer system 1) Condensate and washing water from GGH shall be collected in the GGH washing water sump through pipes or trenches. One(1) GGH washing water sump per unit shall be provided. 2) The collected water in the GGH washing water sump shall be transported to the FGD wastewater treatment system via the GGH washing water sump pumps furnished by the Bidder. The Bidder shall provide associated piping, fittings, automatic isolation valve, etc. 6.26-25 KHABAT TPP UNITS 1&2 - VOLUME I
6.26.3.3 Limestone slurry preparation system A.
General description 1) The limestone slurry preparation system will consist of limestone powder storage silos, screw feeders, pumps, tanks, etc. and one(1) train will be in stand-by for the Max. sulfur oil and maintenance of another train. The limestone slurry preparation system shall be capable of 24 hours operation per day and 7 days operation per week. 2) Limestone powder of [325] mesh size will be delivered from tank lorry. Limestone powder in the tank lorry shall be transported by pneumatic conveying system to two(2) limestone powder storage silos through conveying pipe. 3) Screw feeders shall deliver limestone from the limestone powder storage silos to the limestone solution tanks. Filtrate water shall be added to the limestone solution tank. 4) In the limestone solution tank, limestone slurry will be prepared for 25% wt. concentration. Limestone slurry shall be pumped from the limestone slurry storage tanks to the absorbers of two(2) units by the limestone slurry feed pumps. 5) The limestone slurry preparation system shall be equipped to automatically drain and vent all non-free draining slurry piping upon shutoff of flow to the piping leg. 6) The Bidder shall design and provide facilities to prevent large particles or inert from causing equipment damage, nozzle and pipe plugging in limestone slurry preparation system.
6.26-26 KHABAT TPP UNITS 1&2 - VOLUME I
B.
Number of components The Bidder shall provide, but not be limited to, equipment including the following : Items
Common
A. Air Compressor for Pneumatic Conveyor (include Air dryer)
One(1) set
B. Limestone Powder Storage Silo
Two(2) sets Two(2) sets ( One(1) at each silo )
C. Screw Feeder D. Limestone Solution Tank
Two(2) sets
E. Limestone Solution Tank Agitator
Two(2) sets ( One(1) at each tank )
F. Limestone Slurry Transfer Pump
Two(2) sets (One set standby)
G. Limestone Slurry Storage Tank
One(1) set
H. Limestone Slurry Storage Tank Agitator
One(1) set
I. Limestone Slurry Feed Pump
Two(2) sets (One set standby)
J. Limestone Area Sump Pump
Two(2) sets (One set standby)
K. Limestone Area Sump Agitator
C.
One(1) set
Limestone powder storage silo 1) Limestone powder storage silo shall have minimum 30 days storage capacity based on usable storage volume and a apparent density of [980~1,120] kg/m3 2) The related equipment shall be designed considering the following conditions: a) The limestone powder density - Pneumatic conveyor belts capacities
:
[1,120] ㎏/㎥
- Calculations of drive and pneumatic
:
[1,120] ㎏/㎥
:
[1,820] ㎏/㎥
conveyor belts strength - Structural steel
3) Limestone powder storage silo shall be consist of cylindrical and conical section, skirt plate stiffeners, dust collection system and all attachments, as specified herein.
6.26-27 KHABAT TPP UNITS 1&2 - VOLUME I
4) Provision for emergency off loading of the silo to a truck such as flange connection shall be provided by the Bidder. 5) Limestone powder storage silo shall be made of more than 10mm thick carbon steel with external stiffener and supports.
Plates and
structural steel shall be in accordance with ASTM A36 unless otherwise noted. Plate welds shall be full penetration tested and all welds shall be carefully examined to insure that there are no slag inclusions, craters, cracks, or undercuts. Defects shall be removed by chipping or grinding and then rewelding.
Hoppers shall have a
minimum slope of 60°. 6) Limestone Powder Storage Silo cone shall be lined with stainless steel with a surface profile equal to a 2B finish. 7) All curved plates and structural members shall be figured to the proper shape by pressure and not by blows.
Plate edges for both
shop and field welds shall be manufactured to be beveled and accurately cut. 8) One silo cone with plate shall be shop assembled to check fit before delivery.
Silos shall be shipped in the largest knock down parts to
reduce field welding to a minimum. Equipment and material shall be packed to prevent distortion or damage during shipment. 9) Each silo shall be provided with external ladders, ladder cages, landing platforms, rail guards at the periphery of the silo roof, covered manholes, relief valves, vent filters, and any other attachment required for safe operation and maintenance. 10) Limestone powder storage silo shall be consist of high and low level switches and equipment for the level measurements. Silo level shall be indicated and annunciated locally. 11) Limestone powder storage silo shall be supported equally spaced about the circumference on the support beam (ring beam), beneath the skirt and on the straight side of the silo just above the point of coning. 12) Dust collection system a) General - The design of the dust collection system is the Bidder's responsibility. The dust collection system shall be installed in limestone silo and loading hopper. 6.26-28 KHABAT TPP UNITS 1&2 - VOLUME I
- Limestone Service system, provisions shall be fabricated the containment of limestone dust and the prevention of dust emission to the atmosphere. The dust collection system shall be located outdoor or indoor. The Bidder shall design the detail drawing of dust collectors showing the arrangement. - Dust collection system shall be designed to meet the emission limits. b) The Bidder shall design dust collection systems for silos. The dust collector shall be designed on the basis of continuous operation. Air volume and air to cloth ratio shall be designed on continuous operation at 150 percent of initial design capacity. c) The dust collectors shall have the following safety features ; Pressure differential dial gauge to indicate pressure drop through the collector. d) Dust collectors shall be equipped with necessary supports, platforms, handrails, filter bags and all other items as maybe required. e) Bidder shall perform to assemble all dust collector and accessories, and shall test and ship them.
All piping and valves
shall be shop assembled and tested. All instrument and control components shall be properly protected during shipment and transportation to jobsite. Bidder shall make provisions for lifting assembled units into place without damage. f) Dust collectors shall be available to easy maintenance so that any bag can be replaced without removal of other equipment. g) Duct collector shall be fabricated of galvanized steel more than 3.5mm thickness. h) The top of the collector shall have an upper plenum chamber, which houses the compressed air supply to the bag nozzles for reverse flow pulses of high pressure air at regular intervals. The compressed air supply shall be provided with controls, timers, solenoid valves, nozzles and all interconnecting piping. i) Maximum outlet dust loading of all dust collector shall be less than 50mg/S㎥. D.
Screw feeder 6.26-29 KHABAT TPP UNITS 1&2 - VOLUME I
1) Bin vibrator bottom shall be provided to discharge limestone from the silo to the screw feeder. 2) Screw type weighing feeder and rotary feeder shall control the limestone flow from the silo to the solution tank. 3) Screw feeder shall be adjustable to any feed rate over the full range of designed feed rate.
Load cell shall be designed with built-in
overload protection and shall be compensated for temperature. Screw feeder weigh accuracy shall not exceed ±0.5 percent for 0 to 100 percent of feeder capacity. 4) The screw feeder shall be provided with a local emergency stop pushbutton, local test push button with lockout provision, remote operation, and a feeder discharge plug switch and alarm. 5) The screw feeder shall be designed with variable speed drives and equipped with a manually adjustable flow regulating gate. 6) Screw feeder shall be subject to the requirements for the following, but not be limited to : a) Screw feeder shall be horizontal, heavy duty and supported by structural steel beams. b) Material of the feeder shall be STS304 or equivalence. c) The feeder shall be totally enclosed. 7) The feeder shall be designed to deliver the required rate of flow regardless of the type of limestone being handled. E.
Limestone slurry preparation system 1) Limestone slurry preparation system shall be compose of screw feeder, limestone solution tanks with agitator, limestone slurry transfer pumps, limestone slurry storage tank with agitator and limestone slurry feed pumps. 2) The limestone powder shall be conveyed to limestone solution tank with the help of screw feeder for slurry preparation. In the limestone solution tank, limestone slurry will be prepared for 25% wt concentration. 3) Limestone slurry from limestone solution tank shall be transferred to limestone slurry storage tank by limestone slurry transfer pumps.
6.26-30 KHABAT TPP UNITS 1&2 - VOLUME I
4) Two(2) limestone slurry feed pumps shall be provided for two units. One is in operation, the other in stand-by. The impeller tip speed of limestone slurry feed pumps shall be less than 27 m/s. 5) Capacity of each limestone slurry feed pump shall be 115% at BMCR and max. sulfur oil for two(2) units. The Bidder shall furnish the ceramic ball type modulating flow control valves on the individual limestone slurry feed lines to the absorbers. 6) The limestone slurry feed pumps, feed line to the absorbers, and return line to the limestone slurry storage tanks shall be designed in order to maintain min./max. line velocities with in the proper range. Each line shall be equipped with auto-flushing system. F.
Air compressor One (1) number indoor, screw non-lubricating compressor of suitable capacity and discharge pressure complete with accessories shall be provided to convey limestone powder from tank lorry to limestone powder storage silos. Air compressor shall be reciprocating balanced opposed horizontal. Two stage, two cylinder, double acting, non lubricated, heavy duty, water cooled type and shall be designed for continuous operation with high efficiency to satisfy the performance requirements. Satisfactory operation in parallel shall be ensured without any uneven load sharing, undue vibration. noise etc. Air compressor and their drives provided shall be completely interchangeable. Air compressor shall have dry type suction air filter to protect the compressor. The filter inlet area should be large enough to ensure that frequent filter changes are not required. Self priming oil pump for lubrication of frame and running gear shall be provided for air compressor.
E.
Divertor valve Divertor valve shall be used to discharge limestone powder from each pneumatic conveyer line to required silos. These valves shall be remote operated and shall be of proven design and shall be reliable in operation. The divertor valve shall also be used in the solid pneumatic conveyer line upto limestone powder storage silo. The divertor valve should be of 6.26-31 KHABAT TPP UNITS 1&2 - VOLUME I
proven design and shall be reliable in operation. These in line valve should be provided with proven sealing arrangements to prevent any leakage of compressed air. The inline valve shall be of special proven design. Its flap/disc/dome should not come in contact with the limestone powder during conveying. The general particular of limestone powder divertor valve is as under:
F.
Type
Y / In-line type
Method of
Remote operated through
operation
Pneumatic Cylinder/Actuator
Size
By Bidder
End connection
Flanged
Material
M.S. fabricated (with reinforced backing
Body (Y)
plates )/alloy cast iron
Valve Body
Cast Iron
Valve Shaft
STS 304
Piping All fittings such as bends, lateral etc. shall be of alloy cast iron having wear backs of extra heavy thickness. Material hardness specified shall be uniform throughout the metal thickness and surface hardening will not be acceptable. The minimum radius of the bends in powdered limestone lines shall be minimum five times the nominal diameter of the pipe, a spool piece of specified length shall also be provided at the discharge of each bend at beginning of next pipe line segment. The piping design of pneumatic conveying system shall be such that the joints remain leak tight for a very prolonged period of plant life. All joints should be flanged end. At suitable interval (25 to 30 meters) pipe shall be provided with an expansion joints, which shall take care of piping expansion as well as for clearing of line blockage and easy dismantling of pipe. All the flanges should be alignment type, one flange should have a projection and the other should have groove so that when they are tightened together perfectly aligned joints are there. All expansion joints used in pneumatic conveyer line shall be of proven design for such services.
6.26-32 KHABAT TPP UNITS 1&2 - VOLUME I
Provision of vent pipes with isolation plug valve of DN25/DN50 for detection of line blockage in limestone powder transportation line shall be included in the scope. 6.26.3.4 Gypsum dewatering system A.
General description 1) The gypsum dewatering system shall be capable of 24 hours/day and 7 days/week operation. This dewatering system shall be continuously capable of receiving slurry from the units 1&2 absorbers and producing gypsum. The gypsum dewatering system shall consist of two(2) trains. With one(1) trains in operation, the other train will be in stand-by for Max. sulfur oil and maintenance of another train. 2) The gypsum slurry from the units 1&2 gypsum bleed pumps shall be collected in the gypsum dewatering feed tanks. The gypsum slurry in the gypsum dewatering feed tanks shall then be transferred to the primary dewatering system by the gypsum dewatering feed pumps. 3) Primary dewatering system will consist of 1st stage hydrocyclone. The overflow from 1st stage hydrocyclone will flow by gravity to the filtrate tank. 4) Underflow from the 1st stage hydrocyclone will be routed to the secondary dewatering system. The secondary dewatering system shall be vacuum belt filter and shall be located directly below the 1st stage hydrocyclone clusters. 5) After dewatering, the gypsum cake will be transferred to the gypsum handling system. The filtrate from the vacuum belt filter and 1st stage hydrocyclone overflow will be routed to the filtrate tank for use in the FGD system. 6) The filtrate shall be pumped by the filtrate transfer pumps to the units 1&2 absorbers and the limestone slurry preparation system for reuse. Also, the filtrate shall be pumped to the 2nd stage hydrocyclone to control the chloride concentration in FGD system by the 2nd stage hydrocyclone feed pumps. 7) The overflow from the 2nd stage hydrocyclone will be routed to the FGD wastewater blowdown tank, and pumped to the FGD wastewater treatment system by the FGD wastewater blowdown pumps. The underflow from the 2nd stage hydrocyclone will be routed to the filtrate tank. 6.26-33 KHABAT TPP UNITS 1&2 - VOLUME I
8) Cake washing shall take place in the secondary dewatering system to remove chlorides for achieving an acceptable gypsum product. The washing water shall be discharged to the filtrate tank. 9) All equipment in this system shall be designed as indoor type. 10) The Bidder shall design the wastewater blowdown system and control method to maintain the chloride concentration below 1000ppm continuously in absorber. 11) The related equipment shall be designed considering the following conditions: a) Maximum slope of inclined belt conveyor( if any ) : b) Maximum belt speed (Gypsum conveyor)
15 degrees
: 60 m/min
c) The gypsum density - Storage capacities
:
1,089 ㎏/㎥
- Belts capacities
:
1,120 ㎏/㎥
- Calculations of drive, belt strength and structure steel B.
:
1,920 ㎏/㎥
Number of components The Bidder shall provide, but not be limited to, equipment including the following. Item
Total Number (for two(2) units)
A. Gypsum dewatering feed tank with agitator
One(1) set
B. Gypsum dewatering feed pumps & motors
Two(2) sets (One(1) set standby)
C. 1st stage hydrocyclone
Two(2) sets (One(1) set standby)
D. Vacuum belt filters including necessary accessories
Two(2) sets (One(1) set standby)
E. Filtrate tank with agitator
One(1) set
F. Filtrate return pumps & motors
Two(2) sets (One(1) set standby)
G. 2nd stage hydrocyclone feed pumps & motors
Two(2) sets (One(1) set standby)
H. 2nd stage hydrocyclone
One(1) set
I. FGD wastewater blowdown tank with agitator
One(1) set
6.26-34 KHABAT TPP UNITS 1&2 - VOLUME I
J. FGD wastewater blowdown pumps & motors
Two(2) sets (One(1) set standby)
K. Gypsum dewatering area sump pumps & motors
Two(2) sets (One(1) set standby)
L. Gypsum dewatering sump agitator
C.
One(1) set
Hydrocyclones 1) The hydrocyclone cluster shall consist of multiple cyclones. Each hydrocyclone shall be operated at a constant flow rate. 2) The Bidder shall design the underflow from the 1st stage hydrocyclone to be 40 ~ 50% solids and overflow to be less than 5% solids. And the Bidder shall design the overflow from the 2nd stage hydrocyclone to be less than 1.0% solids. 3) The diameter of the underflow orifice shall be designed so that it controls the underflow-to-throughput ratio. The Bidder shall design the hydrocyclone with a variable underflow orifice size to allow flexibility in meeting the range in design operating condition. 4) The inside walls of the hydrocyclone shall be provided with a smooth, abrasion resistant surface liner such as rubber, polyurethane, ceramic or other suitable lining material. This liner shall also be provided on the overflow nozzle. The hydrocyclone housing shall be coated with corrosion and abrasion resistant lining materials. Each hydrocyclone shall be mounted in vertical or inclined orientation. Hydrocyclone orientation shall prevent plugging of the underflow orifice. To facilitate maintenance, the hydrocyclone assembly shall consist of flanged sections or other suitable arrangements. 5) Where considered necessary to avoid siphoning, the hydrocyclone overflow bends shall be provided with vented pipes. 6) Each hydrocyclone cluster shall have 25% redundancy at maximum load operation. 7) 1st stage hydrocyclone cluster distribution manifold shall include piping and manual knife gate valves to allow isolation of individual hydrocyclones. And, 2nd stage hydrocyclone cluster distribution manifold shall include piping and manual knife gate or ball valves to allow isolation of individual hydrocyclones. The valves will be used for isolation only and shall not be used for control. 6.26-35 KHABAT TPP UNITS 1&2 - VOLUME I
8) Hydrocyclone cluster shall be designed to prevent splashing of slurry from the launders. A curtain or similar device is acceptable. 9) Hydrocyclones shall be arranged in a circular configuration and fed from a cylindrical feed chamber, completely lined with rubber. The feed chamber shall contain no internal partitions, baffles and/or obstructions. The feed chamber shall be designed to provide uniform and constant inlet pressure. A full diameter domed removable cover shall be provided for inspection and maintenance. Feed piping shall be from below the feed chamber. 10) A local pressure gauge with diaphragm seal and capillary shall be provided for monitoring the feed chamber pressure. A pressure indicating transmitter shall be provided for input to the FGD control system for alarm and monitoring the feed chamber pressure. D.
Vacuum belt filter 1) The vacuum belt filter shall produce the dewatered gypsum cake, which is contained less than 15% free moisture. The vacuum belt filter shall be of a continuous feed type design utilizing a combination of gravity and vacuum assisted force as the driving force for the process. A detailed description of the construction, design, operation, and maintenance of the belt filter and vacuum pumps shall be submitted. 2) The structural main frame of the belt filter shall be of steel construction with coatings for corrosion resistance and longevity, which are suitable for the intended service. 3) Belt shall be of the endless type. The belt shall be provided for support of the filter cloth. The rubber belt shall be internally reinforced with a minimum of four layers of woven polyester. Belts shall have tensile strength several times greater than the maximum tension to which the belts are subjected. The belt shall be molded with styrene butadiene rubber. 4) A belt washing system shall be provided to clean the belt after the dried cake has been discharged. The belt washing pipe and nozzle shall be housed in stainless steel enclosure and be provided a highpressure water spray to clean the belt of material that blinds the belts. 6.26-36 KHABAT TPP UNITS 1&2 - VOLUME I
A strainer or cleaning system on the belt washing inlet piping shall be provided and the capability to remove, or clean strainers shall be provided without interruption to the water supply. Where multiple stages of cake washing are required, the filter area shall be divided into segments, the washing water from the segments collected and used as washing water for preceding segments. Booster pumps shall be provided to supply washing water to the belt washing water. 5) The filter cloth shall be continuous fabric belt, and continuously washed after gypsum cake is discharged. The cloth shall be guided by a roller mounted, on a fixed support at one end, and on moving support with pneumatic actuator at other end. Continuous cloth tensioning shall be controlled by a movable roller and can also be actuated by additional tension device. The actuator which shifts the position of the cloth alignment shall be provided and controlled by sensors which actuate when necessary. The filter cloth shall be appropriate for the intended service. The filter cloth shall be designed to operate for minimum 4,000 hours of continuous duty without replacement. 6) Movement of the belt and cloth during the filtration cycle shall be proceeded by the tension pulley, traction pulley, and drive assembly which turns the traction pulley itself. The pulley shall be mild steel welded construction with internal reinforcement. Speed variation required by the range of operating conditions is achieved through a frequency variation system that allows motor rotation speed to be varied. 7) A discharge blade shall be provided at the outlet end of belt filter before washing to scrape the gypsum from the belt filter to a collection system. Blade tensioning system parts shall be made of corrosion-resistant material. Double-edged blade shall be provided to reduce frequency of replacement or resurfacing. 8) The Bidder shall design the bearings to be easily accessible for external maintenance and service. Bearings shall be double sealed to prevent contamination. Bearing life shall be designed on the basis of maximum load. 9) Vacuum boxes and drainage piping shall be corrosive resistant materials connected to the vacuum belt filters. The Bidder shall 6.26-37 KHABAT TPP UNITS 1&2 - VOLUME I
design and provide sufficient drainage capacity to allow washing out the vacuum belt filters, as well as to contain waste streams during normal operation. 10) A gypsum cake thickness monitoring system shall measure the gypsum thickness through the ultrasonic level sensor coated corrosion resistant material and increase or decrease the belt speed by the sensing signal. 11) If vacuum assisted force is used for the belt filter, all auxiliary equipment items to support the proper functioning of the filter shall be provided. 12) Vacuum pump shall be provided to furnish the necessary pressure differential across the cake and the filter media. The vacuum pumps shall be liquid ring type. Moisture trap and vacuum receiver shall be provided. Where a liquid ring seal is used, water shall be reused. 13) Vacuum receiver shall be provided to separate air from liquid and may act as a reservoir for the suction line of the self-priming pump. Self-priming pumps are required to carry the water separated in the vacuum receiver to necessary place. 14) Each vacuum pump shall be furnished with inlet filter, silencers, vacuum breakers, valves, fittings, instrumentation and accessories. Each pump shall be driven by its own motor. The vacuum pump and driving motor shall be mounted on a common support frame. 15) The Bidder shall provide the quick coupling connection equipment at the vacuum belt filter area and ground floor. The service water will be utilized to manually clean the floor by flexible hose connected by quick coupling connection. E.
Gypsum dewatering feed and transfer equipment 1) For FGD system of two(2) units, the storage tank shall be designed and furnished as the following. a) One(1) gypsum dewatering feed tank : The tank shall have a minimum available storage capacity of six(6) hours of gypsum slurry produced by FGD system of two(2) units. b) One(1) filtrate tanks : The tank shall have a minimum available storage capacity of four(6) hours of filtrate produced by FGD system of two(2) units. 6.26-38 KHABAT TPP UNITS 1&2 - VOLUME I
c) One(1) FGD waste water blowdown tank : The tank shall have a minimum available storage capacity of two(2) hours of FGD waste water blowdown quantity produced by FGD system of two(2) units. 2) Each gypsum slurry storage tank shall be designed to receive the gypsum slurry products of any absorber for two(2) units. 3) All tanks shall be vertical cylindrical shape and made of carbon steel with corrosion resistant lining, and shall be equipped with agitator for solids suspension. 4) Two(2) transfer pumps for tanks of each service shall be provided, and each pump shall take suction from all tanks of each service. FGD waste water blowdown pumps shall be designed to cover more than maximum FGD wastewater blowdown flow rate produced from the two(2) units. F.
Gypsum dewatering sump pump and agitator Gypsum dewatering sump pumps and agitators shall be provided for gypsum dewatering system area draining.
6.26.3.5 FGD wastewater treatment system A.
FGD wastewater pond and air blower Two(2), 100% capacity air blower shall be provided with all accessories such as air diffuser pipe, sleeve nozzle, sleeve pipe, embedded material, support etc. and the supplied material shall be suitable corrosion resistant material.
B.
pH adjust, reaction and coagulation tank 1) The capacity of pH adjust and reaction tank shall have a 10 minute retention time in order to react with chemical. Coagulation tank shall have a 20 minute retention time. The type of the those tank shall be rectangular, and shall have a agitator. The agitator shall be mounted on the top of those tanks 2) The agitator for pH adjustment, reaction and coagulation tank shall consist of shaft, propeller or paddles, lubricated bearings, constant speed and gear reducer. The tanks shall be made of rubber lined carbon steel and agitator shall be lined with minimum 3mm of FRP or equivalent.
6.26-39 KHABAT TPP UNITS 1&2 - VOLUME I
C.
Chemical injection system(acid, caustic, alum, polymer for coagulation and polymer for dehydrator) 1) The chemical dissolving/injection tank shall be provided with inlet, outlet, overflow, drain, level gauge connection nozzle etc. The dissolved chemical shall be dosed to proper tank automatically by injection pump. 2) The chemical dissolving/storage tank and injection tank shall be constructed by FRP or equal in according with application code. 3) The capacity of dissolving/storage tanks shall be sufficient for three(3) day's usage or minimum 2 ㎥, whichever is bigger. The capacity of injection tanks shall be sufficient for one(1) day usage or minimum 1㎥. 4) The agitator for each chemical dissolving/storage tank and injection tank shall be provided with proper support. 5) All accessories such as platform, ladder, handrail, mono rail etc. shall be provided for chemical dilution, operating and maintenance 6) The chemical tank and pump shall be skid mounted as per each kind of chemical including all accessories such as piping, calibration cylinder, support, electrical and instrumentation etc. 7) Two(2), 100% of each chemical injection pumps shall be provided with the single-acting, internal self relief, positive-displacement diaphragm type including drive motors, reduction gears, stroke and guards 8)
The acid and caustic injection pumps shall be provided with electro stroke controller in order to control of chemical feed rate.
9) Fume scrubber shall provide for acid injection tank. 10) The chemical feeding equipment shall be provided for the equipment using powder chemicals. D.
Clarifier and thickener 1) The clarifier and thickener shall be made of A283 Gr.C or equal in accordance with code and standard and shall be lined FRP with minimum 3 mm thickness including internal facilities. 2) The bottom of clarifier and thickener shall have sufficient slope for solids collection by scraper.
6.26-40 KHABAT TPP UNITS 1&2 - VOLUME I
3) The platform with handrail shall be installed in the top of clarifier and thickener across the center driving device. The driving device shall have a sufficient torque to rotate the rake arm. 4) The thickened sludge from the thickener shall have the 4% solid or more. 5) The Bidder shall design the clarifier as follows; a) Retention time
: 2~5 hours
b) Surface loading
: 15~20 ㎥/㎡.day
c) Efficient depth
: 3~4 m
d) Linear velocity of driver
: 1~2 m/min.
6) The Bidder shall design the thickener as follows;
E.
a) Retention time
:
0.5~2 day
b) Surface loading
:
25~40 kg/㎡.day
c) Efficient depth
:
2.5~4 m
ZLD(Zero Liquid Discharge) system 1) The pre-heater, 1'st and 2'nd heat exchanger, evaporators, concentrate tank and filtrate tank shall be made of super austenitic stainless steel(6% Mo or equal). The tube of pre-heater and 1'st and 2'nd heat exchanger shall be made of titanium or equal. The condenser tube shall be made of 316L stainless steel. 2) The evaporator shall be the forced recirculating type by circulation pump. The capacity of heat exchanger shall be designed up to 110% waste water rate. 3) The others material such as pumps, piping, valves etc. in contact with FGD wastewater shall be made of suitable corrosion resistant material. 4) All pressure vessel shall be designed and fabricated in accordance with the requirement of ASME Section VIII including all accessories for the operating and maintenance.
F.
Chemical injection system for ZLD system 1) The Bidder shall provide the cleaning facility with all accessories for ZLD system. The capacity of CIP tank and pump shall be sufficient for evaporator cleaning. The tank shall be made of 316L stainless steel
6.26-41 KHABAT TPP UNITS 1&2 - VOLUME I
and heater shall be made of 316 stainless steel or equal in according with application code. 2) The Bidder shall provide the anti-foam injection facility with all accessories for ZLD system. The capacity of tank shall be sufficient for three(3) day's usage or minimum 2 ㎥, whichever is bigger. The tank shall be made of FRP and agitator shall be made of 316 stainless steel or equal in according with application code. 3) The Bidder shall provide the anti-scale injection facility with all accessories for ZLD system if required. The capacity of tank shall be sufficient for three(3) day's usage or minimum 2 ㎥, whichever is biggest. The tank shall be made of FRP and agitator shall be made of 316 stainless steel or equal in according with application code. 4) The chemical tank shall be provided with inlet, outlet, overflow, drain, level gauge connection nozzle etc. 5) The agitator for each chemical tank shall be provided with proper support. 6) All accessories such as platform, ladder, handrail, mono rail etc. shall be provided for chemical dilution, operating and maintenance 7) The chemical tank and pump shall be skid mounted as per each kind of chemical including all accessories such as piping, calibration cylinder, support, electrical and instrumentation etc. 8) Two(2), 100% of each chemical injection pumps shall be provided with the single-acting, internal self relief, positive-displacement diaphragm type including drive motors, reduction gears, stroke and guards. G. Dehydrator package 1) One(1), 100% capacity of belt press dehydrator with cake hopper shall be provided in order to make sludge with all accessories as follows; a) One(1) 100% cake hopper with air cylinder b) One(1) 100% sludge mixing tank with agitator c) One(1) 100% recycle tank d) One(1) 100% auto strainer e) Two(2) 100% recycle washing pump
6.26-42 KHABAT TPP UNITS 1&2 - VOLUME I
2) One(1), 100% capacity of centrifuge dehydrator for ZLD system shall be provided in order to make crystallized solids with all accessories. 3) One(1), 100% capacity of vacuum dryer package shall be provided in order to make crystallized solids with all accessories. 6.26.4
Instrumentation & controls
6.26.4.1 General A.
All instrument and control systems shall be designed, supplied and erected to operate reliably and safely under the operating conditions without experiencing undue strain, wear, heating, vibration, corrosion or other operational difficulties.
B.
For critical control measurements, such as FGD inlet pressure, absorber differential pressure, absorber slurry pH, temperature for emergency quenching, etc., the Bidder shall install redundant measuring instruments.
C. PLC based control cubicles and complete field instrumentation for the automatically controls and monitoring shall be provided. D. Minimum two(2) operator interface station(per unit) with dual LCD monitor(21” min.) and printer shall be provided. E. The control system shall be designed to enable the operator to supervise and operate the system by using LCD/keyboard in local and OWS in CCR. F. The control system shall be provided with the data communication interface devices with PCS for the supervisory control and monitoring in the central control room. G. Electro-magnetic type flow meter shall be provided for all slurry flow measurements, and the material of sensing element shall be titanium to prevent corrosion free against slurry. H The Bidder shall provide ultrasonic level transmitters for all slurry tank and sump level applications. Level detectors for absorber reaction tanks shall be the differential pressure type level transmitter with flushing connection. Cage float, displacer and gauge glasses are not acceptable for slurry tank level instrumentation. I.
The Bidder shall provide the SO2 analyzer with the probe might be installed on a duct directly. The sensor probe shall be mounted on the side of the duct, which projects into the gas stream. Particulate, moisture, vibration and other gases presented in the measurement gas shall not interfere with its performance. The analyzers with the control unit shall 6.26-43 KHABAT TPP UNITS 1&2 - VOLUME I
provide sufficient output signals for the designed and specified purposes. The probes should be mounted at suitable positions to give representative readings of flue gas components concentration at the FGD plant inlet and outlet. The equipment supplied shall be suitably protected against corrosion, dust, vibration and water ingress. J. The pH values of various sample points of the process circuits shall be measured with standard glass electrode. The analyzer shall have a full auto cleaning device for cleaning the probe. The cleaning cycle shall be programmable. The flushing and cleaning times shall be freely definable. During the flushing, the sensor shall be retracted for cleaning, and during the measuring, the sensor shall enter the measuring position. The cleaning water used for the pH electrode shall not contact the process during its normal operation and cleaning period. K.
Slurry density meter requirements shall be provided to measure the slurry density for optimum control of the oxidation and gypsum slurry bleeding loops. The density meter should not have an affection from the air in the process fluid.
6.26-44 KHABAT TPP UNITS 1&2 - VOLUME I
6.27
Waste Water Treatment System
6.27.1
System description The waste water originating from the power plant can be classified into three categories such as normal waste water, abnormal waste water and oily waste water. The normal waste water is generated from water treatment system, sampling system, boiler CBD, etc. and abnormal waste water is generated during boiler chemical cleaning, E/P washing, A/H washing or boiler start-up. The oily waste water is generated during rainfall season at the fuel oil storage tank area and transformer area as well as from the turbine building, fuel building, workshop building, etc. The surface water generated by rainfall rates of up to the first 5mm shall be collected and treated by the oily water treatment system. The waste water generated from each source of the power plant shall be treated by the wastewater treatment system with physical and chemical method and treated water shall meet the emission regulation.
6.27.1.1
The normal waste water is transferred to the neutralization pond, and mixed/aerated by the surface aerator. The waste water in pond is neutralized with acid and caustic transferred from water treatment system. The pH shall be monitored and recorded. This water is transferred into the clarifier by the neutralized water transfer pump.
6.27.1.2
The oily waste water is transferred into the API oil separator. Oil is removed in the API oil separator and CPI(Corrugated Plate Separator) and treated water flows into the normal waste water pond.
6.27.1.3
The abnormal waste water is transferred to the abnormal waste water pond. The abnormal waste water is neutralized with acid and caustic. This water will be treated by the same method as normal waste water.
6.27.1.4
Alum and alum aid transferred from water treatment system are fed into the clarifer. The suspended solid, organic and inorganic matter in the waste water, is coagulated.
6.27.1.5
The clear water separated in the clarifier is collected into the clarified water pond and the settled sludge is transferred into thickener by sludge pump.
6.27-1 KHABAT TPP UNITS 1&2 - VOLUME I
6.27.1.6
The residual suspended solid and sludge in clear water is removed by an activated carbon filter.
6.27.1.7
The pH of treated water is controlled in the final pH adjustment pond with caustic or acid. This treated water flows into the final disposal channel or is used as filter's backwash water.
6.27.1.8
The water separated in the thickener flows into the neutralization pond. The sludge thickened in the thickener flows into the thickened sludge storage pond and is transferred to the dehydrator by thickened sludge transfer pump.
6.27.1.9
The sludge dewatered by the dehydrator will be treated and the recycled water is returned to the neutralization pond.
6.27.2
System design criteria
6.27.2.1
General The Bidder shall design the wastewater treatment system to treat the wastewater discharged from each source of the power plant, and determine the wastewater treatment system capacity based on the wastewater discharge rate and concentration per each source. The capacity of waste water treatment system shall be designed capable of treating for 16hours/day. When abnormal waste water is generated, the waste water treatment system shall be operated for 24hours/day.
6.27.2.2
Design parameters A.
General All equipment, piping and accessories shall be designed meeting the following conditions: 1) Pressure a) Equipment
Max. allowable
Activated Carbon Filter b) Piping and accessories 2) Temperature, deg. C B.
Working Pressure
1.5
150 lbs class, STD wall pipe Max. 95
Reinforced concrete ponds and/or tanks shall be as follows: 1) API oil separator a) Number of pond, set
One(1) × 100% 6.27-2 KHABAT TPP UNITS 1&2 - VOLUME I
b) Type
Underground, open, rectangular
c) Material
R/C
d) Interior protection
Modified epoxy coating or eq.
2) Oil separated water pond a) Number of pond, set
One(1) × 100%
b) Capacity
Max. oily wastewater rate per day
c) Type
Underground, open, rectangular
d) Material
R/C
e) Interior protection
Modified epoxy coating or eq.
3) Abnormal waste water pond a) Number of pond, set
One(1) × 100%
b) Capacity
Max. abnormal wastewater rate/day
(including chemical cleaning during shutdown period) c) Type
Underground, open, rectangular
d) Material
R/C
e) Interior protection
Modified epoxy coating or eq.
4) Neutralization pond a) Number of pond, set
One(1) × 100%
b) Capacity
Max. normal wastewater rate per day
(including oily wastewater and filter wash water) c) Type
Underground, open, rectangular
d) Material
R/C
e) Interior protection
Modified epoxy coating or eq.
5) Clarifier a) Number of pond, set
One(1) × 100%
b) Type
Abovegroud, open, cylindrical
c) Material
R/C
d) Interior protection
Modified epoxy coating or eq.
6) Clarified water pond a) Number of pond, set
One(1) × 100%
b) Type
Underground, open, rectangular
c) Material
R/C
d) Interior protection
Modified epoxy coating or eq.
7) Final pH adjustment pond a) Number of pond, set
One(1) × 100%
b) Type
Underground, open, rectangular 6.27-3 KHABAT TPP UNITS 1&2 - VOLUME I
c) Material
R/C
d) Interior protection
Modified epoxy coating or eq.
8) Final disposal pond a) Number of pond, set
One(1) × 100%
b) Type
Underground, open, rectangular
c) Material
R/C
d) Interior protection
Modified epoxy coating or eq.
9) Thickener a) Number of pond, set
One(1) × 100%
b) Type
Abovegroud, open, cylindrical
c) Material
R/C
d) Interior protection
Modified epoxy coating or eq.
10) Thickened sludge storage pond
C.
a) Number of pond, set
One(1) × 100%
b) Type
Underground, open, rectangular
c) Material
R/C
d) Interior protection
Modified epoxy coating or eq.
Normal and abnormal waste water treatment System 1) Surface aerator for abnormal waste water pond a) Number of aerators, sets
Two(2) × 50%
b) Type
Surface aspiration aerator(Floating type)
2) Abnormal waste water pump a) Number of pumps
Two(2) × 100%
b) Type
Horizontal, Centrifugal
c) Material - Case SSC 14 or eq. - Impeller SSC 14 or eq. - Shaft STS 316 or eq. 3) Surface aerator for neutralization pond a) Number of aerators, sets
Two(2) × 50%
b) Type
Surface aspiration aerator(Floating type)
4) Neutralized water transfer pump a) Number of pumps, sets
Two(2) × 100%
b) Type
Horizontal, Centrifugal
c) Material 6.27-4 KHABAT TPP UNITS 1&2 - VOLUME I
- Case SSC 14 or eq. - Impeller SSC 14 or eq. - Shaft STS 316 or eq. 5) Clarifier rake a) Number of collector
One(1) × 100%
b) Type
Center Driving
c) Revolution
0.02 ∼ 0.05 rpm
d) Material
Carbon steel with rubbercoating or eq.
6) Clarified water pump a) Number of pumps
Two(2) × 100%
b) Type
Horizontal, Centrifugal.
c) Material - Case GC 25 or eq. - Impeller SSC 13 or eq. - Shaft SM 45C or eq. 7) Activated carbon filter a) Number of filters
Two(2) × 100%
b) Type
Vertical, Cylindrical
c) Linear velocity
10 ㎥/㎡·hr
d) Material
Carbon steel or eq.
e) Interior protection
Modified epoxy coating or eq.
8) Filter backwash pump a) Number of pumps
Two(2) × 100%
b) Type
Horizontal, Centrifugal
c) Material - Case GC 25 or eq. - Impeller SSC 13 or eq. - Shaft SM 45C or eq. 9) Agitator for Final pH adjustment pond a) Number of agitator
One(1) × 100%
b) Material
Carbon steel with rubber lining or eq.
10) Agitator for thickened sludge storage pond a) Number of agitator
One(1) × 100%
b) Material
Carbon steel with rubber lining or eq.
11) Sludge pump a) Number of pumps
Two(2) × 100% 6.27-5 KHABAT TPP UNITS 1&2 - VOLUME I
b) Type
Horizontal, Centrifugal
c) Material - Case GC 25 or eq. - Impeller SSC 13 or eq. - Shaft SM45C or eq. 12) Thickened sludge transfer pump a) Number of pumps
Two(2) × 100%
b) Type
Horizontal, Centrifugal
c) Material - Case GC 25 or eq. - Impeller SSC 13 or eq. - Shaft SM45C or eq. 13) Dehydrator a) Number
One(1) × 100%
b) Type
Belt Press Filter
c) Cake moisture content
80 %
d) Accessory Sludge mixing tank(or thickener) with agitator, recycle tank, recycle washing pump, auto strainer, etc. 14) Cake hopper a) Number of tank
One(1) × 100%
b) Type
Rectangular
c) Material
Carbon steel or eq.
d) Interior protection
Modified epoxy coating or eq.
e) Accessory
pneumatic actuator
15) Pump room sump pump a) Number of pumps
Two(2) × 100%
b) Type
Vertical, Centrifugal
c) Material - Case GC 25 or eq. - Impeller SSC 13 or eq. - Shaft SM45C or eq. 16) Exhaust Fan a) Number
One(1) × 100%
b) Type
Vertical, Cylindrical
c) Material
FRP or eq. 6.27-6 KHABAT TPP UNITS 1&2 - VOLUME I
D.
Oily waste water treatment system 1) Oil separated water pump a) Number of pumps
Two(2) × 100%
b) Type
Horizontal, Centrifugal
c) Material - Case GC 25 or eq. - Impeller SSC 13 or eq. - Shaft SM45C or eq. 2) CPI a) Number of separator
One(1) × 100%
b) Type
CPI
c) Material - Body A283 Gr.C or eq. - Pack FRP or eq. E.
Chemical injection system 1) C-Polymer injection tank for dehydrator a) Number of tank
One(1) × 100%
b) Type
Vertical, Cylindrical
c) Material
FRP or eq.
d) Accessories
Dissolving basket, Electric heater
2) C-Polymer injection tank agitator for dehydrator a) Number of agitator
One(1) × 100%
b) Material
STS 304 or eq.
3) C-Polymer injection pump for dehydrator a) Number of pumps
Two(2) × 100%
b) Type
Diaphragm, Metering
c) Material Head STS 316 or eq. Diaphragm Teflon or eq. Check Ball STS 316 or eq. 6.27.3 6.27.3.1
Design and construction features General
6.27-7 KHABAT TPP UNITS 1&2 - VOLUME I
A.
The waste water treatment plant shall be designed so as to insure continuous, safe, and economical operation providing the maximum reliability without vibration and noise.
B.
Duplication of components shall be maximized to the greatest possible extent so that similar components shall be interchangeable.
C.
Each item of the waste water treatment plant equipment shall be shop assembled, properly aligned, and if required, matchmarked and assembled for shipment, and the Bidder shall state the equipment disassembled and provide subassembly drawings for shipment.
D.
The equipment and all assembly joints or junctions shall include alignment or centering fits as required to ensure accurate reassembly or alignment of all parts.
E.
Structural steel walkways and stairways shall be provided, and the walkway shall be extended to the full dimensions of the equipment for monitoring and maintenance.
F.
Accessories for concrete pond, namely, walkway, stairway, ladder, sleeve for piping, handrail etc. shall be supplied by the Bidder, and all accessories for the clarifier and thickener also shall be supplied by the Bidder.
G. The design of all items specified shall conform to OSHA design requirements. H.
The waste water treatment system shall include the equipment to measure the flow, temperature, pH, SS and COD of the final treated water.
6.27.3.2
Waste water treatment system A.
Normal and abnormal waste water treatment system The normal waste water which is drained into each sump or pit from the waste water sources (building drain, laboratory, etc.) shall be transferred into the neutralization pond by sump pump and stored there. The abnormal waste water shall be transferred into the abnormal waste water pond by sump pumps. And then, abnormal waste water shall be transferred into the normal waste water pond by pumps. Chemical injection shall be done in the abnormal and normal waste water ponds, clarifier, the final pH adjustment pond and the sludge mixing tank. Cleaned water from the clarifier shall be transferred to the activated
6.27-8 KHABAT TPP UNITS 1&2 - VOLUME I
carbon filter by pumps. Thickened sludge will be treated and dewatered by dehydrator. The cakes shall be collected and removed. 1) Surface aerator An electric motor driven propeller aspirator aerator, which induces the flow of atmospheric air below the surface of the water, shall be provided. Aerator elements shall be suitable for continuous operation and structural frames, anchoring cables and floats shall have maximum corrosion resistance in severe waste water environments. 2) Activated carbon filters After removing SS and COD in the clarifier, the influent shall be filtered by the activated carbon filter. a) Two(2) activated carbon filters shall be provided and shall be of the vertical type, preassembled, piped, wired, and tubed. b) The filters shall contain filtering media and shall be furnished in accordance with AWWA standards for filtering media. If required, support media shall be provided. Each filter shall be equipped with all automatic valves required to operate the unit and bypass pipe. Service, backwash, rinse, and drain valves shall be of the automatic butterfly type. c) Two(2) filter backwash pumps, each of 100% capacity, shall be provided. Two(2) backwash pumps shall be used for backwashing. d) Activated carbon filter shall be fabricated of A 515 Gr.60 or eq. in accordance with ASME code section Ⅷ. The vessel interior shall be lined with a minimum modified 0.3mm of epoxy. The internal upper and lower distributors shall be constructed of STS316L and shall evenly distribute all flows. Internals shall be factory assembled. 3) Sludge handling units a) The sludge from the clarifier shall be collected in the thickener by the sludge pumps. The sludge shall be thickened in the thickener prior to dewatering. By thickened sludge transfer pumps, the sludge shall be supplied to a belt press system. The sludge shall be dewatered by the belt press and removed by KNOC. b) The clarifier and thickener rake shall consist of rake arms driven by a variable speed drive. As a part of the drive unit an overload 6.27-9 KHABAT TPP UNITS 1&2 - VOLUME I
protecting
device
shall
be
furnished.
Take-up
motor
and
accessories shall be provided on the drive mechanism. c) The rake arm will remove the settled sludge to a central discharge point. The blade shall be bolted to the bottom chord of truss structure of rake arm. The rake and rake support parts submerged below the liquid level shall be STS 316 or eq. for protection against abrasion and corrosion. 4) Chemical injection system a) Chemicals (acid, caustic, alum, alum aid) will be supplied from water treatment system. b) C-polymer injection tank shall be provided with a hinged cover, structural steel supports, overflow, drain, fill connections, and walkways, stairways and handrails including all accessories for the operation, inspection and maintenance. The capacity of the tank shall be sufficient for one day's usage. The chemical tank shall be provided with agitator. c) Chemical injection tank shall be constructed of FRP or equivalent. d) Two(2) flooded suction positive displacement, diaphragm type pumps shall be provided for each chemical with accumulators for dehydrator. On-off valve for the protection of siphon shall be installed at the chemical injection pump discharge. e) The injection tank and pump shall be skid mounted including piping, support, electrical and instrumentation etc.. B.
Oily waste water treatment system Oil contaminated water is led to each sump from the plant area. Oily water shall be transferred to the API oil separator by sump pumps and pretreated in the API oil separator. The pretreated oily waste water is led to the oil separated water pond. The pretreated oily waste water is transferred to the CPI and treated. The treated water is led to the neutralization pond through piping.
6.27.3.3
Pipings & valves A.
The Bidder shall supply all piping, valves, fittings, supports and appurtenances necessary to make a completely self supporting system.
6.27-10 KHABAT TPP UNITS 1&2 - VOLUME I
B.
The Bidder shall provide piping from the discharge of chemical unloading and transfer pumps to the waste water treatment system.
C.
All piping design shall be in accordance with ASME B31.1 power piping. The Bidder shall fabricate piping spools ready for installation. Particularly lined pipes shall be the same.
D.
Piping connections of DN50 and smaller shall be the socket weld type and piping connections of DN65 and larger shall be the butt-weld type. Flanges shall be provided where required for connections to lined pipes, equipment and valves.
E.
The Bidder shall furnish all chemical feed piping. All piping in contact with strong or dilute acid shall be made of lined pipes or equivalent. The lining shall be sealed with an applicator approved by the KNOC. No welding shall be done on the lined pipe. All piping in contact with caustic, alum and alum aid shall be low carbon austenitic stainless steel(A 312 TP 316L,Welded) or equivalent.
F.
The piping between the discharge of the neutralization pond, abnormal waste water pond and the inlet of the clarifier shall be polypropylene lined carbon steel.
G. All drain valve connections shall be located at least 200mm above the floor. H.
The Bidder is responsible for the sizing of piping within the terminal points of the supply scope.
I.
All flanges of piping including terminal points shall be in accordance with ANSI B 16.5 standard.
J.
The valve in contact with chemical waste water shall be the diaphragm type or equivalent.
K.
Branch lines and valves including all accessories for the discharge shall be installed at all pipings.
6.27.3.4
Pumps and accessories A.
Pumps shall be designed to receive and support all forces and moments associated with start-up, normal operation, and temperature changes. Duplicate pumps for the same service shall be designed to operate in parallel, at reduced flows, without undue noise and vibration and danger of shaft breakage.
6.27-11 KHABAT TPP UNITS 1&2 - VOLUME I
B.
Pump casings, motor supports, and counter flanges and bases shall be capable of withstanding the forces resulting from all conditions of steady and transient operating conditions during startup or shutdown of pumps.
C.
The Bidder shall draw up and provide the list of materials which he recommends and guarantees under the specified conditions of operation, and shall completely describe the proposed material by specification and analysis.
D.
Impellers shall be the enclosed type, keyed to the shaft for pump rotating assemblies which are dynamically balanced.
E.
Sealing shall be standard packing gland. The glands shall be constructed to permit their inspection and packing removal without disturbing other parts of the pump. Adequate provision shall be made to collect gland leakage and drain it from the pump. The Bidder may submit, as an alternative to standard packing glands, a mechanical seal which he recommends for the service. Seal water shall be applied to all packed pumps.
F.
Pump shafts shall be provided with replaceable sleeves where they pass through the stuffing boxes. The sleeves shall be hardened and sealed adequately to prevent air or liquid from leaking between shaft and sleeve. Sleeves shall be rigidly positioned without set screws.
G. Pumps shall be provided with replaceable wearing rings. H.
All pump and motor bearings shall be heavy duty, oil or grease lubricated. Oil lubricated bearings shall be suitable for lubrication with turbine oil. Constant level oilers shall be provided for oil lubricated bearings.
I.
Flanges shall be faced and drilled according to ANSI 16.5 standards.
J.
Pump shafts shall be accurately machined and ground and of adequate size and strength to maintain all clearances and withstand safely all stresses resulting from weight to be supported.
K.
Pumps shall be horizontal, radially split, frame mounted, single suction type, complete with drive motor, base plate, and all required accessories for complete operable units.
L.
Baseplates shall be either fabricated steel or cast iron, with drip lips and 20mm minimum drain connections. The baseplates shall extend completely under both pumps and drivers.
M. Coupling shall be spacer type (stainless steel double disk flexible type), where required to allow dismantling of the pumps without disturbing the 6.27-12 KHABAT TPP UNITS 1&2 - VOLUME I
motors or the pump pedestals. Metal coupling guards shall be provided to cover coupling exposed keyways. N.
Chemical injection pumps shall be the metering, positive displacement diaphragm type and shall be furnished complete with drive motors, reduction gears, stroke control devices, Y-type strainer and guards, all mounted on a common baseplate.
O. Pump flowrate and head shall be determined by the Bidder and shall be of adequate capacity to allow the system to perform as specified. P.
Strainers(Y-Type) for the pumps shall be installed on the open concrete ponds except settled and thickened sludge storage ponds.
6.27.3.5
Instrumentation and controls A.
All automatic and manual control action shall be possible through local LCD monitor and PCS's LCD monitor in central control room. And all engineering work shall be possible through the LCD monitor.
B.
Instrumentation and controls shall be designed in accordance with the section 8 of this technical specification.
C.
PLC based control system and complete field instrumentation for the automatically controls and monitoring shall be provided.
D.
Operator interface station with two(2) dual type LCD monitor and printer shall be provided.
E.
The control system shall be designed to enable the operator to supervise and operate the system by using LCD/keyboard in local and OWS of PCS in CCR.
F.
The control system shall be provided with the data communication interface devices with PCS for the supervisory control and monitoring in the central control room.
G. The flowmeter type shall be magnetic on the inlet of each waste water pond, weir or flume with ultrasonic level detector on the outlet of the disposal channel. H.
The Bidder shall furnish all necessary sensing elements, transmitters, and related devices to provide specified annunciations.
I.
Analyzers 1) pH measurement 2) SS measurement 3) COD measurement
6.27-13 KHABAT TPP UNITS 1&2 - VOLUME I
6.27.3.6
Structural and miscellaneous steel All structural steel material, plate and miscellaneous structural fittings shall comply with the ASTM A36, A7, A242.
6.27-14 KHABAT TPP UNITS 1&2 - VOLUME I
6.28
Sewage Water Treatment System
6.28.1
System description The sewage water treatment system shall be designed according to requirement stated on this specification. The sewage water treatment facility shall be designed to meet the quality of the final effluent before being discharged to the river.
6.28.2
System design criteria
6.28.2.1
Design conditions A.
The design capacity of sewage water treatment system for two uints shall be as following, but it is changable for the detail design by Bidder.
B.
The Bidder shall guarantee that the equipment, materials and all accessories furnished shall be entirely suitable for all operation condition required in this specification. The sewage water treatment systems shall conform to all applicable codes, satisfactorily meet all conditions of performance and design requirements specified herein, and be capable of continuous operation at any condition without detrimental effects.
C.
The Bidder shall also guarantee that all equipment furnished is free from defects in design, workmanship and material, and is of sufficient size and capacity and of proper materials to satisfactorily fulfill the specified operating conditions in this specification.
6.28.2.2
Design parameters A.
Sewage water treatment system 1) Number :
100%×1
2) Capacity (Changable for detail design) :
min. 60㎥/day
3) Type :
Biological method
4) Location :
Underground
5) Material :
by Bidder
6) Assessories : Chlorination equipment B.
Final disposal pump 1) Number of unit :
100%×2
2) Capacity The capacity shall be able to discharge sufficiently the treated sewage water. 3) Type :
Submersible 6.28-1 KHABAT TPP UNITS 1&2 - VOLUME I
4) Material - Casing : GC250 or eq. - Impeller : SSC13 or eq. - Shaft : STS410 or eq. C.
Instrumentation and automatic control equipment 1) Pressure guage a) Type :
Diaphragm Seal Type
b) Size :
Min. 100 mm Round Daial
c) Accuracy :
± 1.0% of F.S
d) Range :
0~1.5 times of Max. operation pressure
2) Level switch
D.
a) Type :
Quick Float Type or Electrode Type
b) Rating :
10A 120V AC, 0.5A 125V DC
c) Enclosure :
NEMA 4X
The control panel for sewage water treatment system and final disposal pump including channel base, anchor bolts, nuts and etc.
E. 6.28.3
Others
Design and construction features
6.28.3.1
The sewage water treatment system A.
The sewage water into treatment system shall at least be treated by screening and primary sedimentation, biological clarification in activated sludge basins, sedimentation for removing the activated sludge and as a last stage an effluent disinfection for discharging into the river. The sewage sludge should be periodically emptied and cleaned by an external company.
B.
The sewage water treatment system(including type, size, capacity and material) shall be adequately manufactured and furnished according to regulation related with sewage water treatment.
C.
The sewage water treatment system shall be stably operated under various quantities of sewage water flow or shall be installed with the type of system which uniformly maintain the inflow quantities of sewage water produced from various condition.
6.28.3.2
Piping system The piping system shall be designed and installed to be successfully
6.28-2 KHABAT TPP UNITS 1&2 - VOLUME I
performed the hydrostatic test, pneumatic test and air tightness test without any defect. 6.28.3.3
Instrumentation and control system A.
The Bidder shall provide the instrument and control equipment which certificated and approved in accordance with the applicable cords and test regulations.
B.
Local control panel 1) The local control panel shall be supplied with one(1) feeder from motor control panel and shall be automatically operated according to the water level. The sewage water treatment system shall be capable of manual control by local control panel. 2) Space heater shall be provided. Thermostatically controlled space heaters equipped with dehumidifier shall be provided so that the temperature inside each panel shall be maintained above the dew point temperature for the conditions of operation and protect the instrument from freezing during the winter. 3) The local control panel shall be capable of the following; a) Automatic/manual start-up and stop of sewage water treatment system and pumps b) Shift operation of operation pump and standby pump
6.28.3.4
Construction features A.
The design of welding and pipework shall meet with requirements stated in ASTM B 31.1 All flange shall meet with requirements stated in ANSI B 16.5.
B.
All equipment shall be shipped and delivered after complete assembling, except in case of conflict with the limitation of regulation related with shipping and delivery.
C.
The Bidder shall submit the welding procedure when the welding is required for manufacture and assembling of equipment. The Bidder shall provide satisfactory electrode in accordance with applicable codes and standards.
D.
All pressure parts shall be performed the hydrostatic test in accordance with applicable code and standards and pumps shall be performed the performance test in accordance with applicable code and standards.
6.28-3 KHABAT TPP UNITS 1&2 - VOLUME I
6.29
Sump Pump
6.29.1
System description The sump pump with completed accessories will be used to transfer waste water & sanitary water through the related piping system to the waste water & sewage water treatment system or ditch.
6.29.2
System design criteria
6.29.2.1 Design conditions A.
General The sump pump system shall be designed throughout so as to insure continuous, safe and economical operation providing the maximum of reliability and without undue noise, vibration, instability, unbalance, scaling, plugging, overheating, abrasion and corrosion.
B.
Design conditions System design shall be based on following conditions 1) Sewage water O Quality Assumed BOD5(mg/l)
min. 300
Assumed Suspended Solids(mg/l)
min. 200
Assumed Nitrogen(mg/l)
min. 60
2) Oily waste water O Quality Assumed pH
6–9
Assumed Oil and Grease(mg/l)
50 - 200
3) Boiler blowndown water O Quality Assumed pH
9 - 11
Assumed Temperature(℃)
Max. 100
4) Chemical waste water O Quality Assumed pH
2 - 11
6.29-1 KHABAT TPP UNITS 1&2 - VOLUME I
C.
Design parameters As the type of waste water, the material and pump type shall be as follows : Items
Sewage
Chemical Water
Oily Water
Storm Water
Pump Type
Submersible
Vertical
Submersible or Vertical
Submersible
Casing & Strainer
GC250 or eq.
SSC16 or eq.
GC250 or eq.
GC250 or eq.
Impeller
SSC13 or eq.
SSC16 or eq.
SSC13 or eq.
SSC13 or eq.
Shaft and sleeves
STS304 or eq.
STS316L or eq.
STS304 or eq.
STS304 or eq.
Sump cover plate and base plate
A36 or eq
A36 or eq
A36 or eq
A36 or eq
The sump pumps to transfer the waste water & sewage water are as follows. But the additional sump pump required transferring the waste water generated besides below mentioned area and the pump capacity, head and sump size shall be determined by the Bidder based on the design conditions in this specification. 1) Sewage water sump pumps Type
Number
Workshop BLDG. Sump Pump
Submersible
100% x 2
Administration BLDG. Sump Pump
Submersible
100% x 2
Security Gate House Sump Pump
Submersible
100% x 2
Submersible
100% x 2
Submersible
100% x 2
Submersible
100% x 2
FGD waste water treatment BLDG. Sump Pump
Submersible
100% x 2
Unloading entrance gate Sump Pump
Submersible
100% x 2
Name
FGD Control BLDG. Sump Pump Operation & Maintenance Management BLDG. Sump Pump Water & Waste Water Treatment BLDG. Sump Pump
6.29-2 KHABAT TPP UNITS 1&2 - VOLUME I
Chiller BLDG. Sump Pump
Submersible
100% x 2
No.1, 2, 3 Guard Tower Sump Pump
Submersible
100% x 2 (per Sump)
Type
Number
Unit 1 Boiler Area Sump Pump
Vertical
100% x 2
Unit 2 Boiler Area Sump Pump
Vertical
100% x 2
Chemical Storage Area Sump Pump
Vertical
100% x 2
Type
Number
Unit 1 TBN BLDG. Area Sump Pump
Submersible
100% x 2
Unit 2 TBN BLDG. Area Sump Pump
Submersible
100% x 2
Unit 1 Transformer Area Sump Pump
Vertical
100% x 2
Unit 2 transformer Area Sump Pump Fuel Oil Storage Tank Area Sump Pump Fuel & Light Oil Pump House Sump Pump Fuel Oil Emergency Tank Sump pump
Vertical
100% x 2
Vertical
100% x 2
Vertical
100% x 2
Vertical
100% x 2
Light Oil Storage Tank Area Sump Pump
Vertical
100% x 2
Workshop BLDG. Sump Pump
Vertical
100% x 2
Emergency Diesel BLDG. Sump Pump
Vertical
100% x 2
AUX. Boiler Area Sump Pump
Vertical
100% x 2
Type
Number
Submersible
100% x 2
2) Chemical water sump pump Name
3) Oily water sump pump Name
4) Other sump pump Name Raw Water Intake Canal Area Sump Pump
6.29-3 KHABAT TPP UNITS 1&2 - VOLUME I
6.29.3
Design and construction features
6.29.3.1
General A.
The Bidder shall provide sumps and sump pumps wherever wastewater will be generated in the power plant.
B.
Pumps will be of advanced and well-proven design suitable for handling abrasive and corrosive waste water & sewage water. All components of the waste water transfer pumps which come into contact with the waste water & sewage water will be made of corrosive and abrasive resistant material with excellent durability for the intended service.
C.
Each sump pump shall be a vertical/submersible, centrifugal, electric motor-driven, non-clog unit of the wet-pit type with suction screen.
D.
Each pump and its components shall be constructed of the best materials available for the most severe service conditions under which each pump will be required to operate. All materials of construction shall be identified with ASTM or ASME specification numbers.
E.
The Bidder shall design the maximum noise level of pump and motor not to exceed 85dB(A) of overall sound pressure level at a distance of one(1) meter from each equipment.
F.
The pump shall be capable of operating over the whole operation range with efficiencies as high as possible, and be free of harmful effects from vibration, cavitation or recirculation.
G. The pumps shall be installed to be capable of service without any intervention while one(1) operate and one(1) stand-by or two(2) operate at the same time. H.
The pump shall be able to be both automatically operated by level switch and manually operated by local control panel. Level switch shall be provided with adequate material and type about the fluid.
I.
The Bidder shall guarantee the following performance of pumps and motor drives 1) The performance guarantee of pump 2) Rated Capacity 3) Total Differential Head 4) Pump Speed 5) NPSH required or minimum submergence 6) Efficiency at Rated Capacity 7) B.H.P at rated capacity 6.29-4 KHABAT TPP UNITS 1&2 - VOLUME I
8) Acoustic Requirement(dB(A)) 9) Vibration(Shaft, Housing) 10) The performance guarantee of motor drive 11) Rated Output 12) Full Load Speed 13) Efficiency at 100% Rated Load 14) Power Factor at 100% Rated Load 15) Temperature Rise 16) Maximum Starting Current at Rated Voltage 17) Full Load Torque at 100% Rated Voltage J.
Pump shall not be damaged by reverse flow due to check valve failure in discharge line.
K.
Pumps shall be of a proven heavy duty, liberal design to assure equipment as maintenance free as possible, and long life reliability.
L.
Pumps designed for same service and operating conditions shall be identical in all respects so that pump parts are interchangeable, in so far as general arrangement permits.
M. To avoid excessive vibration, the Bidder shall verify that the nearest critical speed of each combined pump unit specified herein (each motor and pump) is at least 25% below or above the motor operating speed. The vibration levels as measured on the thrust bearing housing or the top motor bearing (if the thrust bearing is located in the motor) shall not exceed the level specified by the Hydraulic Institute at design speed and flow conditions. The same vibration level also shall not be exceeded when pumps are coming up to speed or are operating at less than full flow. N.
Pump discharge column shall be of such design so as to permit removal of the entire pump unit for maintenance and repair without dismantling any portion of the discharge column.
O. Bolts, nuts, studs and screws shall have threads conforming to ANSI standards, coarse thread, or equivalent, and shall be finished in accordance with the latest approved practice for the duties involved. P.
The Bidder shall provide the discharge pressure gauges with root valve.
6.29-5 KHABAT TPP UNITS 1&2 - VOLUME I
6.29.3.2
Shaft and impeller A.
Impellers shall be vortex, non-plug or semiopen, depending on the Bidder's standard. Impellers shall be statically and hydraulically balanced radially to ensure smooth operation under all conditions.
B.
Each impeller shall be securely keyed and locked to the shaft.
C.
Shafts shall be designed to withstand all stresses, including those from rotor weight, hydraulic loads and thrust, and full voltage starting. Pump shaft shall be of suitable steel type and of ample diameter to prevent any whipping action or other disturbance under any operating conditions.
6.29.3.3
Bearing A.
Pump bearing capacity shall be over than 130 percent of the maximum load imposed when pumping the maximum amount of solids. Bearings shall have an average life rating over than 5 years continuous operation. All pump bearings shall be equipped with either a forced grease feed system or a sight feed lubrication system. Grease fittings or oil cups shall be located above the pump baseplate or above sump cover plate. Intermediate guide bearings shall be provided
B.
Rotating equipment in access controlled areas shall be sealed for life bearings or grease lubricated bearings, size permitting, or where oil lubrication is used slinger rings and oil collection devices shall be used to collect and contain leakage rather than let it drip or spill to base plates or floors.
C.
The intermediate and case bearings shall be the sleeve, dry lube type for all pumps.
6.29.3.4
Couplings Couplings for vertical wet-pit sump pumps shall be solid flanged steel flexible couplings, statically balanced, and designed for the pump load.
6.29.3.5
Casing A.
Castings shall be uniform so that the deviation of thickness shall be less than 10 percent from Bidder's standard. Each casting shall be sound and free from cracks, pits, or nodules.
B.
Waterways shall be finished of good commercial quality.
C.
Bolt holes on all flanges, including nozzles, case-to-cover joints, etc., shall be commercial standard. Bolt holes shall straddle centerlines. 6.29-6 KHABAT TPP UNITS 1&2 - VOLUME I
6.29.3.6
Cover plate A.
The sump cover plate shall be designed for non-gaslight installation. Bolt holes shall be drilled in the pump manufacturer's standard locations.
B.
Each cover plate shall adequately support the equipment, under static and dynamic conditions, without sagging more than 0.1 inch and shall be not less than 1/2 inch thick. The Bidder shall provide any structural steel stiffeners for the sump cover that may be required.
C.
Provisions shall be made in the design of the sump cover plate so that each individual pump can be removed as a unit without disturbing the operation of the other pump.
D.
The pump baseplates shall be not less than 1/2 inch thick. The baseplate shall be fitted with above the floor flanged discharge connection and bolt holes drilled to match those in the sump cover plate.
E.
The size of manhole shall be big enough for access inside sump during maintenance. Final arrangement of the pumps and accessories will be indicated on Bidder's general arrangement drawings.
6.29.3.7
Submersible pump A.
The Bidder shall provide guide support, guide pipe, guide holder chain for automatic installation & removal and pump lifting device, which include chain, power cable, cable holder, guide support and automatic connection discharge pipe for pump lift to out of sump or pond, to maintain easily.
B.
Shaft seal for sewage water sump pump shall be exclusive mechanical seal for sewage water only and shall protect from entrance of water and solid into the motor.
C.
The material of submersible equipment including casing, shaft, bolts and nuts, etc. shall have abrasion and corrosion resistance quality.
6.29.3.8
Drives A.
The Bidder shall provide the pumps with motors in accordance with Section 7.
B.
Motor rated horsepower shall not be exceeded at the specified pump rating by the impellers selected for the service. The service factor may be used infrequently, but the horsepower shall not be exceeded by any operating condition that can be developed by the installed impellers.
6.29-7 KHABAT TPP UNITS 1&2 - VOLUME I
6.29.3.9
Piping & valves The Bidder shall supply all piping, valves, fittings, supports and appurtenances necessary to make a completely self supporting system except where specifically excluded. All piping systems shall include flanged connections, in accordance with ASME/ANSI B16.5, to permit convenient disassembly of sections and removal of installed components for maintenance and replacement. Valves shall be designed for the maximum pressure, temperature, and chemical conditions to be utilized. The pipe materials will be the following: 1) Sewage(above ground), oily water(above ground), Storm water(above ground) : Carbon steel pipe 2) Sewage(underground),
oily
water(underground),
Storm
water
(underground) : HDPE pipe 3) Chemical water : Carbon steel pipe with rubber lined 4) Boiler Blowdown water : Stainless Steel pipe The facing of connection flange for the discharge connection will be the following: 1) For Steel Pipe : RF Type 2) For HDPE Pipe : FF Type 6.29.3.10 Instrumentation and controls A.
The Bidder shall provide completely all local instruments and accessories required for the operation of the sump pump.
B.
The Bidder shall supplied local control panel for the sump pump control.
C.
Instrumentation and controls shall be designed in accordance with the section 8 of this technical specification.
D.
Local control station shall be provided with voltage free contact for Plant Control System(PCS) as follows 1) Pump fault (common for main pump & standby pump) 2) Sump level extra high
6.29-8 KHABAT TPP UNITS 1&2 - VOLUME I
6.30
Piping
6.30.1
General 1)
Scope of work The design, manufacture, installation and testing of piping systems shall be in accordance with approved ASME B31.1 code During the design , the Bidder shall supply to the KNOC schedules of the piping systems provided under this Contract. The schedules shall state, for each piping system, the design code, pressures and temperatures, the piping materials and contents, the valve type and materials, corrosion allowances, piping supports and insulation proposals and any other data relevant to the mechanical design of the piping system or part thereof. Unless otherwise specified or approved, all pipes shall be of seamless drawn carbon or alloy steel. In any one system or piping service all piping and fittings shall be of the same material or similar analysis. All piping shall be routed to provide a neat and economical layout so that full access is provided for the operation and maintenance of equipment and that removal or replacement of equipment can be achieved with the minimum dismantling of piping. The number of joints shall be kept to a minimum necessary. Tees and bends shall be to standard dimensions. Bends shall be of the pulled type or forged. Hot bending with packing may be used for larger sizes according to facilities available, but hot bends in alloy or stainless steels shall be subject to approval of the KNOC. No crimping or flattening of the bend will be accepted. Where employed for low pressure piping, gusset or miter bends shall be designed to the relevant piping code. Where piping is subject to mechanical cleaning (pigging) the bend radius shall be not less than 5 pipe diameters. Piping work shall include piping design, procurement, manufacturing and delivery of materials, installation, cathodic protection if required, test, 6.30-1 KHABAT TPP UNITS 1&2 - VOLUME I
cleaning, painting, commissioning and their drawings or reports. Piping includes fitting, flange, valve, trap, strainer, flexible hose or expansion joint, support, thermal insulation and lagging and accessories. Major pipe’s size and wall thickness calculation, main steam, reheat steam, HP & LP bypass steam and boiler feed water pipe’s stress calculation and analysis shall be submitted. Design drawings especially piping arrangement shall be approved by KNOC. Isometric and support drawings shall be submitted for information. Vendor drawings especially piping specialty, that is, steam trap, expansion and flexible joint, strainer, flow nozzle, desuperheater drawings, etc. shall be submitted for information by Bidder. Drawings of the high pressure pipe work which show amongst others the magnitude and direction of the thrust on the turbine steam chest, boiler superheater outlet header, economizer inlet header, feed pumps, feed heaters, brine heaters and reducing stations, both in the hot and cold condition, shall be submitted to the KNOC for information. The responsibility, however, lies with the Bidder. Provision shall be made for steam blowing and chemical cleaning. All such branches serving the purging and cleaning process shall have flanged connections type. Blank flanges shall also be provided. The Bidder shall supply the isometric drawings for information including supports, branches and expansion joints. The isometric drawings will be accompanied by a complete nomenclature. The Bidder shall complete sets of all isometric drawings in an agreed format for each line or system, properly classified and will keep it continuously updated with the latest revisions of the isometrics. Pipe welding, cleaning and hydrostatic or pneumatic test procedure shall be submitted prior to execution of their work and inspection or test result 6.30-2 KHABAT TPP UNITS 1&2 - VOLUME I
report shall be submitted. During the contract, the Bidder shall supply to the KNOC schedules of the pipe work. The schedules shall state, for each pipe system or parts of a pipe system, the design and operating pressures and temperatures, the fluid transmitted, the piping and valve materials, the types of valves, any corrosion allowances, the piping design code, insulation proposals, pipe supports and any other data relevant to the mechanical design of the pipe work or part of a pipe work. The Bidder shall submit detailed comprehensive pipe and valve specifications for approval. After contract, the bidder should submit pipe line designation list based on P&ID This specification shall state in minimum design and operating pressure and temperature, the fluid transmitted, the piping and valve materials, types of valves, any corrosion allowances, piping design code, insulation proposals and piping supports. 2) Piping material Systems operating in the area of materials creep rupture strength shall be designed for a system live time of 200,000 hours. In this and other parts of this Specification the term high pressure refers to steam piping where the design pressure exceeds 17 bars and to other systems where these values exceed 24 bars. Piping operating temperature exceeded 400 ºC shall not use of carbon steel material. The use of cast iron pipes will not be allowed without KNOC’s approval. The steels shall be suitable to withstand the temperature 6.30-3 KHABAT TPP UNITS 1&2 - VOLUME I
and pressure conditions involved in the operation of the plant under all circumstances. In any one system or pipe service all pipe work and fittings shall be of the same material or similar analysis unless specified or agreed by the KNOC. No crimping or visible flattening at the bend will be accepted. The following standard pipe sizes shall be used for the different systems: Diameter in DN 25, 40, 50, 80, 100, 150, 200, 250, 300, 350, 400 etc. Diameter larger than DN 600 pipe size may be fit in AWWA standard. Pipes with a diameter size smaller than DN 25 may be used only for control air, control oil, chemical dosing, sealing water, instrument connections, cooling water connections to equipment, sampling pipes and input pipes. Any plastic piping required to be used in outdoor applications shall be fully suitable to withstand the effects of sunlight over the life of the plant and shall be subject to the KNOC’s approval. Plastic pipes above 150 mm nominal diameter shall not be site run and design arrangements shall be submitted to the KNOC for approval. Where plastic pipe work is used it shall be arranged to minimize the risk of accidental damage during plant operation or maintenance. Flanges shall comply with the requirements of the code to which the piping is designed. Flanges having ratings less than ASME class 150 or AWWA class B will not be permitted except where agreed with the KNOC. Bolts, studs, nuts and washers for flanges are shall be galvanized for carbon steel and plastic flanges, and stainless steel for stainless steel 6.30-4 KHABAT TPP UNITS 1&2 - VOLUME I
flanges. Jointing of thermoplastic piping shall be carried out in strict accordance with the manufacturer’s recommendation. Demineralized water, potable water, instrument air piping shall be stainless steel. The Bidder shall complete the detail piping material specification sheets by piping classes according to the following applicable service of piping material data sheets and these shall be approved by the KNOC. Corrosion allowances as noted below shall be used in design calculations of all pressure components and this shall be in addition to any allowances for manufacturing tolerances and tube thinning during manufacture: All major pressure part components such as the steam drum, Headers, and down comers shall include 2.5 mm All Water wall, roof and hanger tubes shall include 1 mm or 10% of minimum calculation thickness which ever is the larger. In order to prevent the possible conversion of the carbide phase of carbon steel tube and pipe materials to graphite they shall not be employed when metal temperatures exceed 425°C. Similarly to avoid the use of extrapolated stress data found in some design codes the following maximum design temperatures shall be used in relation to the low alloy materials described:
1-1½% Cr steels, maximum allowable design temperature 480°C
2-2¼
Cr steels, maximum allowable design temperature
520°C
9-12% Cr steels, maximum allowable design temperature 580°C
6.30-5 KHABAT TPP UNITS 1&2 - VOLUME I
Applicable service of piping material data sheets Applicable Service
Pipe Material
Service Air Raw Water (above ground) Closed Cooling Water
ASTM A53B
Waste Water (A/G, non-chemical) Service Water (A/G) Misc. Vents & Drains BFP Suction COP Suction LP Heater Extraction Steam Aux. Steam Light Oil Pump Suction
ASTM A106B
COP Discharge Deae. Extraction Steam Light Oil Pump Discharge Cold Reheat Steam Chilled Water
ASTM A53B with Galvanized-Flanged
Main BFP Discharge
ASTM A106C
Boiler Feedwater FWH#5,6,7 Ext. Steam
ASTM A335P11
LP Bypass (PCV Downstream)
ASTM A335P11
LP Bypass (PCV Upstream)
ASTM A335P92 or Equivalent
Fuel Oil
API 5L - Gr B
Main Steam
ASME/ASTM A335P92 or Equivalent
Hot Reheat Steam
6.30-6 KHABAT TPP UNITS 1&2 - VOLUME I
Demi. Water Potable Water Condensate Transfer
ASTM A312TP304
Instrument Air Sanitary Water Chemical Feed Hotwell Sampling Pump Suc. LP Sampling
ASTM A312TP304L
Chemical Feed Condensate Sampling Condensate Sampling Hot Reheat Steam Sampling Main Steam Sampling
ASTM A312TP316
Feedwater Sampling
Circulation Water (A/G - DN65& Larger)
ASTM A53B with Rubber Lined
Circulation Water (U/G)
GRP
Chemical Waste Water Fire Fighting (A/G)
ASTM A53B with Galvanized
Non Chemical Waste Water – Under Ground Floor & Equip. Drain – U/G
HDPE or GRP
Potable Water (U/G) Fight Fighting (U/G)
Note; a) The Bidder may propose alternative materials to those specified above. In each case, the Bidder shall demonstrate to the satisfaction of the KNOC that the proposed alternative materials are equivalent to or superior to those specified.. b) All boiler pressure parts shall be designed and constructed to withstand the forces and moments applied through the main steam,
6.30-7 KHABAT TPP UNITS 1&2 - VOLUME I
cold and hot reheat, feed and integral pipework under all service conditions. c) . Plastic pipe shall not be used to convey chemical reagent solutions of >5% w/w strength or where the fracture of the pipe could pose danger to personnel. 3) Corrosion protection All above ground fuel pipes shall be protected against corrosion in accordance with the Painting and Protection requirements defined in this specification. Buried portions shall be protected against corrosion with factory applied coating and cathodic protection, suitable for the ground conditions. The selection of coating and method of application shall be to the approval of the KNOC and shall be taken to ensure mechanical and electrical compatibility with the cathodic protection system.
4) Cathodic protection Cathodic protection shall be applied by the impressed current method to all buried pipework. The cathodic protection shall be brought into operation immediately upon completion of the pipeline construction with the protection designed and installed in accordance with the requirements
as
defined
in
the
Cathodic
Protection,
This
Specification. Particular note shall be taken of the presence of other buried services in the area of gas pipeline and the procedures of the relevant internationally recognized codes and standards : Part 1 shall be followed.
5) Fire main The pressurized fire main shall be designed on a ring main basis and sized to cater for the maximum water demand in accordance with NFPA 24. Valves (normally locked open) shall be fitted at appropriate 6.30-8 KHABAT TPP UNITS 1&2 - VOLUME I
points in the main to allow isolation of discrete sections of the site. All thrust blocks (if required), valve pits, vent and drain connections and corrosion protection measures are to be provided. The capacity and layout of the main, and the position of hydrant outlets shall be submitted for approval. Above ground piping shall be ASTM A106 seamless carbon steel or approved equivalent, galvanized and painted in red. The pipe size up to DN50 shall have pipe schedule 80 having screwed joints and above DN65 to be standard schedule with flanged joints. The pipe material including fittings, flanges and bolting etc. shall meet the appropriate codes requirement of ASTM and ASME standards. The valve material shall be steel body and bronze trim and shall meet the design rating of the system. The material for buried pipework, valves and fitting up to the above ground connection point at the valve station shall be ductile iron (ISO 2531) with mechanical joints, cement lined (AWWA C104) with external bituminous coating and polyethylene wrapped (AWWA C105). Buried valves shall be grey cast iron body complying with the requirement of MSS SP70 and ANSI B16.1. All buried pipework shall be accommodated in trenches which are excavated and backfilled to ground level with the requirements of the relevant internationally recognized codes and standards, the depth of cover over the crown of the pipe shall be not less than 900 mm. 6.30.2
Layout A.
Piping arrangement The layout of the piping shall be subject to approval by the KNOC. The Bidder shall submit with his Proposal, layout drawings illustrating the proposed distillate oil supply ,heavy fuel oil and crude oil supply and transfer systems including the pumping station, the piping arrangement in the tank area and all major items of equipment. The drawings shall indicate the position of all supports, drainage points, fittings and all closing pipes. However, all piping systems shall be 6.30-9 KHABAT TPP UNITS 1&2 - VOLUME I
arranged to allow for adequate slopes in the direction of flow. All piping shall be routed to provide a neat and economical layout and requiring the minimum number of fittings. Piping shall be arranged so that full access is provided for the operation and maintenance of equipment, and that removal or replacement of equipment can be achieved with the minimum dismantling of piping. Overhead piping, inclusive of fittings, insulation and support steelwork, shall have a minimum vertical clearance of 2.1 meters above access platform and walkways and 6 meters above roadways. As far as it is possible all process pipes shall be above ground on pipe supports. Wherever the pipes have to cross roads or other facility, this shall be achieved by proper pipe trench. No direct buried pipes are acceptable for fuel oil in the plant battery limit. At the point of drainage, drain pockets of sufficient size and approved construction shall be fitted Drain piping shall be separately run to the blow down tank or drain tank as may be appropriate. The venting system shall serve as a safe removal system for all possible hydrocarbon vapour occurring during regular operations or emergencies. All vent gases shall be collected in a closed piping system which shall direct the gases to a venting stack, where they are vented safely. The drains from gas scrubbers and gas filters and from other points shall be led to a common underground concrete pit from where the same will be pumped via effluent pumps to mobile tankers. All gas vessel nozzles shall be flanged, and equipment shall be fitted with isolation valves to permit removal for maintenance without interrupting the gas supply
6.30-10 KHABAT TPP UNITS 1&2 - VOLUME I
The meter shall be located such that sufficient straight lengths of piping are provided both upstream and downstream of the device.
1) High pressure and high temperature pipe work All branch connections shall be designed with due consideration to both reinforcement and compensation. Where forged steel tees are used, they shall be of similar material analysis to the adjacent pipe, and they shall match correctly the bore of the adjacent piping and shall be proportioned to avoid stress raisers. The main steam pipe work shall be designed to the maximum safety valve lift pressure and the maximum design temperature condition. Air release and drain branches shall be provided where necessary, arranged in such a way that the drains and air release valves in they locations can be operated easily. Drain and air release pipe work shall be designed for the maximum pressure of the service line to be drained. Drains shall run separately to the point of discharge. Each high-pressure drain and vent with pressure-temperature rating of ASME class 600 and above shall be fitted with two valves at the nearest drain point at basement level in an approved manner. The valves arrangement shall allow a convenient operation. Provision shall be made to prevent scalding during operation. All steam pipes minimum drainage fall shall be 1/200 (0.5%) at any hot or cold condition. The desuperheating pipe work shall be designed to withstand the maximum pressure of the feed pump and the final feed temperature.
6.30-11 KHABAT TPP UNITS 1&2 - VOLUME I
2) Feed water pipe work The feed water pipe work shall be designed to withstand the closed valve pressure of the feed pump and the final feed temperature. Boiler feed water pump minimum flow pipe work up to and including minimum flow control valve shall be designed for the closed valve pressure produced by the feed pump as specified in the schedules. Minimum flow piping shall run to the feed water storage tank and shall be connected to an internal diffuser pipe fitted inside the tank.
3) Fuel oil pipe work, valves and fittings All fuel oil pipe work shall be designed, constructed, installed and tested in accordance with ANSI B31.3 or equivalent internationally recognized standards. All buried fuel oil pipe work shall be accommodated in trenches which are excavated, prepared and backfilled in accordance with; the depth of cover over the crown of the pipe shall be not less than 900 mm. All isolating valves in the fuel oil systems shall be of the nonlubricated ball type with Teflon seals and resilient faces, where applicable. The valves shall be of the fire-safe design. Threaded valves shall only be used where required for equipment compatibility. Cast iron valves shall not be used for oil service. All piping and equipment shall be protected against excess pressure utilizing pressure relief valves. Over pressurization of blocked or isolated pipelines and equipment by solar heating and ambient temperature changes shall be considered in the design.
Relief valve discharge shall be piped
to the return header or pump suction, as required. Vents and drains equipped with a ball valve shall be provided at strainers and all high points and low points respectively. In addition, connections required for periodic tests shall be equipped with valves 6.30-12 KHABAT TPP UNITS 1&2 - VOLUME I
and threaded nipples which shall be protected by threaded caps. 4) Lubricating oil pipe work Supporting systems must prevent vibration under all possible operating conditions. Welding shall be used as far as practicable. Where screw joints are used they will be properly secured against loosening by vibration. Arrangement and support of all oil piping shall be such that detrimental vibrations do not occur under any possible operating condition. Thermowells shall be welded to the pipes. Piping shall be prefabricated in the factory and be dispatched fully acid-pickled and properly sealed and protected against corrosion. The Bidder may consider stainless steel in order to facilitate a fast track programme for oil flushing. Within the boiler block, for ease of pipe fitting on Site, the fitting lengths installed in the various pipe runs shall be flanged to avoid welding on prefabricated pipes. The fitting lengths shall be cleaned and acid-pickled before installation.
5) Compressed air pipe work All compressed air pipe work shall be hot dip galvanized throughout conforming to the relevant internationally recognized codes and standards. All galvanizing shall wherever possible be carried out after fabrication work. Where pipes are cut or screwed after galvanizing this shall be made good. All galvanized pipe connections shall be threaded, or flanged, but not welded. All branches shall be taken from the top of the mains. Each branch pipe to compressed air points shall terminate in a standard fitting. The mains shall have a suitable slope to allow drainage and shall be 6.30-13 KHABAT TPP UNITS 1&2 - VOLUME I
fitted with automatic drain traps and the necessary isolating and bypass valves. Instrument - and control air connections from the mains to the consumers shall be made of 316L stainless steel pipes with screw fitting joints. Similarly 316L stainless steel piping shall be utilized between the air compressors and the dryers.
6) Ductile iron pipe work and fittings Ductile iron cement lined pipes and fittings, as used in potable water distribution for underground piping systems, shall comply with the requirements
of
ISO
specifications
as
regards
methods
of
manufacturing, tolerances, marking and testing. The pipes, fittings and rubber rings used for jointing shall be suitable to withstand the operating requirements and ambient weather conditions. Pipes shall be supplied in standard lengths with mechanical joints wherever possible. The specification, dimensions and thicknesses of pipes and fittings, unless otherwise stated, shall comply with the requirements of the latest edition of ISO 2531 standard. Where ductile iron pipes and fittings are supplied with sockets for push-on joints, mechanical or rubber ring, thrust blocks shall be provided at all changes in direction etc. unless the Bidder can justify otherwise. Glands shall be of ductile cast iron of the same quality as the fittings and tested for tensile strength and hardness. Glands shall be marked with the manufacturer’s name, date of manufacture and nominal diameter and coated with a 4 mm thick bituminous compound. For easy maintenance all valves and interconnection sections shall be flanged. All fittings with flanged ends of 600 mm diameter and smaller shall be in accordance with ASME B16.1/B16.5. Bolts and nuts shall be of galvanized mild steel and gaskets shall be of rubber and reinforced, of thickness not less than 3 mm and shall conform to AWWA C11.
6.30-14 KHABAT TPP UNITS 1&2 - VOLUME I
7) Floor and wall opening collars, wall boxes and weather hoods At all points where pipes pass the through concrete or other similar floors and walls, suitable floor collars or wall boxes shall be provided. The floor collars shall have raised curbs of suitable height, which shall not be less than 75 mm. The wall boxes shall be flush fitting and of neat design and approved finish. The Bidder shall provide all necessary fittings for the passage of pipes through external walls and roofs, together with the supply of all necessary components for weatherproofing or vermin proofing. Wherever possible, service pipes running adjacent to each other shall pass through a common box. Where pipes of varying bore pass through a common box, a neat “fillin” cover plate shall be provided between the pipes and the box. In the case of flanged pipe work, boxes shall be large enough to permit the passage of the flange.
8) Vents and drains Adequate provision shall be made for safely venting, purging, and where necessary, draining those sections of pipework and equipment which have to be isolated during construction, commissioning and maintenance. The venting system shall be suitable for the disposal of vented or emergency relief gases. All vent gases containing hydrocarbon vapours, e.g. during stream purge on shut down operation, shall be piped to safe locations or to a vent stack. Block and bleed with integral vent arrangements shall be provided, where necessary, to ensure plant safety, and purge vents shall include facility for connection of gas detection equipment. Vents and drains only needed for tests shall be plugged and sealwelded; all others shall be equipped with blind flanged or blind plugged gate or ball valves. Vents and drains shall have a minimum 6.30-15 KHABAT TPP UNITS 1&2 - VOLUME I
diameter of DN25. The vent system shall be designed to remove the largest amount of vent gas, which could occur during any reasonably assumed plant condition or emergency expected throughout the power station. Basic and detailed design shall be subject to KNOC’s approval
9) Terminal connections All welding and flange connections shall be carried out unless otherwise specified, by and under the full responsibility of the Bidder. For flange connections the Bidder shall also supply, where appropriate, the companion flange and the necessary jointing material. In case of weld connections the Bidder shall, where appropriate, make good the final joint, pipe protection and reinstatement. Termination points shall be as indicated in the Bidder drawing. The Bidder shall be responsible for finalizing the connection requirements at each termination point and shall agree the precise location and scheduling of interconnection work with KNOC to minimize disruption to existing plant and services. 6.30.3
Fluid vlocities The following maximum fluid velocities are guidelines to be used for the purpose of pipe sizing during the preparation of Bidders. The final selection of fluid velocities and pipe sizing after contract award shall be the responsibility of the Bidder, such selection being subject to review and approval by the KNOC The maximum allowable velocity of flow in pipes shall be as follows:
High-pressure live steam
75 m/s
Low pressure steam lines for FWH Extraction
60 m/s
Saturated steam
40 m/s
Service air
15 m/s
Instrument air
10 m/s 6.30-16 KHABAT TPP UNITS 1&2 - VOLUME I
Feed water
7.3 m/s
Water piping(discharge)
3 m/s
Water piping(suction)
1.8 m/s
Aux. Cooling water in heat exchangers and piping
3 m/s
Fuel oil(discharge)
2 m/s
Fuel oil(suction)
1 m/s
Higher values may be approved in special applications or for systems used intermittently. Pipes of diameter less than DN25 may only be used for control/impulse and chemical dosing. The rating of discharge piping of pumps shall be a minimum of 1.05 times of pump maximum outlet pressure or pump shut-off pressure, whichever is the largest. 6.30.4
Stress calculation The Bidder shall provide, as required by the KNOC, stress calculations and diagrams or print outs from a stress analysis computer program to show the location and magnitude of the stresses and the magnitude and direction of the thrust and resultant bending moments at the terminal points and at each point of restraint in a piping system after contract. The calculations shall be based on the most arduous combination of the specified operating conditions. In minimum, a stress analysis must be performed for all piping systems with an operating temperature≥200℃. The load cases “dead load” and “thermal expansion”, “occasional & seismic load” and “internal pressure” must be verified using the ASME B31.1 criteria. Adequate provision for expansion of the pipe work shall be made. Expansion joints or bellows shall be used only where they can be justified technically and economically and with KNOC’s approval. Piping connected to axial bellows units shall be adequately guided and anchored. 6.30-17 KHABAT TPP UNITS 1&2 - VOLUME I
6.30.5
Cleaning of pipes All items shall be prepared for shipment in such a manner to avoid damage of atmospheric corrosion to inside or outside surface during storage period and while in transit. Plain or bevel ends shall be protected with a non-metallic cover The Bidder is responsible for ensuring that the internal and external surface of all pipelines is thoroughly clean before the pipelines are placed in commission and painting. The internal cleaning may be performed by one of steam, air or nitrogen blowing or chemical cleaning or launching the pig. The procedure adopted is to include the following and may be more specifically described elsewhere in the specification. Thorough cleaning of all internal surfaces prior to erection to remove accumulations of dirt, rust, scale, and welding slag due to site welding before erection. Prior to, and during erection, all parts shall be inspected to make sure that they are clean, and adequate steps shall be taken to prevent entry of foreign matter both during and after erection. Each section erected shall be cleaned out before being connected into the previous section. All headers shall be cleaned before closing up. In the case of high temperature piping, a cycle of heating, cooling and blowing or flushing is to be repeated several times to ensure that any remaining slag or scale which would otherwise become loosened during service, is removed before commissioning. The Bidder shall provide all necessary facilities in the pipe system for carrying out the requirements of items above including any temporary pipe work, valves and supports.
6.30.6
Pipe supports 6.30-18 KHABAT TPP UNITS 1&2 - VOLUME I
Piping shall be supported and anchored in an appropriate manner in accordance with the provisions of ASME B31.1 or the Standard to which the pipe work is designed. Supports shall not be dependent for flexibility on the flexure of supporting rods or straps. Supports shall be positioned before the pipe has been erected and near to valves wherever possible. Supporting straps around flanges or welded joints will not be accepted. All supports shall be provided with means of adjusting the tension of springs, the height of supports and the length of rods or straps. All such adjusting devices shall be capable of being securely locked. Parts of supporting elements for high working temperature piping shall be made of suitable alloy steel or shall be protected so that the temperature of the supporting member will be maintained within the appropriate temperature limits of the material. The supporting arrangements of all piping systems shall be designed with due regard to any additional loads imposed during hydraulic or hydrostatic testing, and cleaning and steam blowing operations. Particular attention shall be paid to sliding surfaces in guides and sliding supports and to the springs employed in variable and constant load supports. The Bidder shall provide stainless steel and low friction plastic for important sliding surfaces. Where necessary, constant load supports shall be provided. The Bidder shall take all necessary precautions to ensure that the piping shall be free from vibration by the installation of sway braces and/or vibration dampers or other acceptable means. Except for springs, all supports shall be designed for a safety factor of not less than 5, based on the ultimate strength of the material. Outdoor piping support systems shall be designed to withstand the environmental conditions. 6.30-19 KHABAT TPP UNITS 1&2 - VOLUME I
Supports shall be so designed and fabricated that, in the event of spring failure, they do not release the pipe. The spring hangers, counter poise support, etc. on pipe work shall have scale showing hot and cold (static and dynamic) load settings marked by punching. Springs shall be of the helical compression type and shall be provided with means to prevent misalignment, buckling, eccentric loading or excessive travel, with a working stress not exceeding 10 N/mm2 at the most favorable loading conditions. The Bidder shall prepare pipe work layout or other similar drawings marked to show the position of every pipe support on all high-pressure piping. Each of the supports marked on these drawings shall be assigned a unique plant reference number by the Bidder. The Bidder shall prepare the drawings of all these supports for submission to the KNOC before erection. The support drawings shall, as a minimum, state the support reference number, the type of support, the directions of freedom of movement, and the magnitude and direction of pipe movement from the cold installed to the hot operating conditions. A spring support drawing shall also be provided to the KNOC and included in the operating manuals, which as a minimum, states the support reference numbers, the spring rates, the hot operating load, and the magnitude and direction of travel from the cold installed to the hot operating conditions. 6.30.7
Underground ppe wrk All underground pipe work shall be designed in order to withstand the loading from covering soil as well as from traffic. Underground piping systems shall be self-anchoring, i.e. no thrust blocks for loadings resulting from test and operation pressure are permitted except in specific areas where partially encased thrust blocks may be provided as reviewed case by case. The cathodic protection system for underground pipe work wherever 6.30-20 KHABAT TPP UNITS 1&2 - VOLUME I
deemed necessary in addition to the insulation proposed by the Bidder shall be approved by KNOC. Where guiding tubes or sleeves for penetrations such as through building walls, walls or dikes of tank farm, etc., of steel are practicable, such material has to be supplied and proper sealing and outside protection carried out by the Bidder. 6.30.8 1)
Valves General All valves shall be manufactured from first quality material, have superior designed parts, dust-tight construction, and have easily maintained lubricating systems. All valve parts shall be arranged for ease of accessibility in the installed position. The design and manufacture of all valves shall be to the approval of the KNOC. Valve information shall be detailed in the appropriate technical data sheets to be included in the Bidder and shall include operating pressure range, nominal set pressure, and type of actuator. Valves shall be suitable for the service intended, with materials suitable for the medium to be handled, and certified as acceptable by relevant codes and standards for the service and duty intended. For the boiler package, the Bidder’s Standard will be considered. Manually operated valves with a nominal size greater than DN250, which have to be opened or closed very quickly or with minimum manual effort shall be provided with a suitable gear system. All isolating valves which are required to open or close during normal operation of the plant, including start up and shut down shall be equipped with an installed actuator and shall be capable of being locked in both the open and closed positions. The Bidder shall provide the necessary devices and locks. The internal diameter of all valves at the ends adjacent to the pipes shall be the same as the internal diameter of the pipes to which they are jointed unless 6.30-21 KHABAT TPP UNITS 1&2 - VOLUME I
otherwise approved by the KNOC. Valves shall have butt weld or flanged ends in accordance with the piping system requirements. Butterfly valves shall only be used when specifically approved. Cast iron, bronze or brass valves are not permitted for any piping system except as specifically mentioned herein. All valves and pipe fittings material shall be as indicated in ASTM code or approved equivalent. All valves of sizes up to and including DN 50 shall be globe valve type and shall have an ASME Class 600 rating for all services. Where globe or angle style valves are used they shall be installed with the normal flow entering beneath the disc. Check valves shall be of the inner-shaft type and no stuffing box or counterweight type check valve shall be permitted. Check valves shall be non-slamming type. Examination and/or replacement of parts shall be possible without removing the check valve from the line. Check valves in vertical pipe runs should be avoided, however, where necessary these shall be provided with by passes and drain valves. Cast or steel-forged bodies shall be used for high-pressure valves >25 bar) with a nominal bore larger than DN 65, and for smaller bore, steel forged bodies shall be used. For low-pressure valves (<25 bar) with a nominal bore larger than DN 250, cast-steel bodies shall be used. Carbon steel shall be used for temperatures below 400℃. For temperatures above 400 C, alloy steel shall be used unless agreed by the KNOC All valves shall be designed to prevent erosion of the valve seats when the valves are operated in a partially open position. In areas with increased hazard valve actuators shall be driven by air with spring to close feature. Only in well justified cases the use of electric actuators will be accepted in those areas. In this case explosion proof design is mandatory. 6.30-22 KHABAT TPP UNITS 1&2 - VOLUME I
Spring load for pneumatic actuators shall be employed to facilitate safety during air failure, i.e. the valve is closed by spring force. However, in the case of the main inlet fuel system block and bleed valves, if there is a loss of air or electric power the valve shall lock in position. Only when there is a fire signal shall these valves “fail close”. Valves with welding ends shall have ready machined ends, which shall match exactly the dimension of the pipe to which the ends have to be welded. The welding ends shall be of the same material as the pipe and shall be long enough to allow heat treatment after welding, without the risk of damage to the valve by temperature increase. All valves shall be installed in such a way that they can be easily operated by one person. Where required, valves spindles shall be sufficiently long, or extended in such a manner that the hand-wheel is at a level of approximately one meter above floor or platform level, from which the valve can be operated. Where required these shall be provided with headstocks and pedestals of rigid construction. Where extension spindles are fitted they shall incorporate two universal joints. All valve pedestals shall be mounted direct on floor girders and not on floor plating. All floor steelwork necessary for supporting pedestals shall be included. Installation with the valve stem oriented downwards/tilted is not acceptable. All valve actuators shall have local indicators fitted to show whether the valves are in an open or shut position. In the case of valves being equipped with extended spindles, indicators shall be fitted to both the extended spindle and to the valve spindle. Motor driven valves shall have position indicators. Plastic or bakelite valve hand-wheels are not permitted. The stops limiting the travel of any valve in the "open" or "shut" position shall be arranged externally to the valve body. All valves shall be closed by turning the hand-wheel in the clock-wise direction when looking on top of the hand-wheel. 6.30-23 KHABAT TPP UNITS 1&2 - VOLUME I
The face of each hand-wheel shall be clearly marked with the words "open" and "shut" in English, with adjacent arrows to indicate the direction of rotation to which each refers. If, due to the use of a gear reducer, the valve has a spindle with a left-turn thread, this should be clearly marked. Each valve hand-wheel shall be fitted with a name-plate of an approved material, indicating in English the valve reference number and function. The name-plate shall incorporate the colour code corresponding to the particular service of the piping. Each valve shall be permanently marked with the code designation of valve, casing material, manufacturer’s serial number, nominal bore and the nominal pressure/test pressure and temperature. Hand-wheels equipped with electric servo motors, or hand-wheels of valves to which a servo motor may be fitted, shall not rotate when the servo motor is in use and shall furthermore, be able to be handled without being mechanically connected to the servo motor. When determining the actuating forces, design pressure for one side and zero (0) bar pressure on the other side of the valve disc (i.e. full differential) shall be assumed. Eye bolts shall be provided where necessary to facilitate handling heavy valves or parts of valves. Valves shall be fitted with approved limit switches where required for interlocking purposes and to implement the control scheme as necessary for remote indication and control. Spindles of valves for outdoor use shall have weatherproof protection covers. In general all valves exposed to the elements shall be corrosion resistant.
6.30-24 KHABAT TPP UNITS 1&2 - VOLUME I
Test certificates for all valves shall be issued by the Manufacturer duly signed by the Inspection Authority.
Valve trim materials for steam service generally should be 316 type stainless steel or equivalent with stellited sealing rings and seats, and all other materials should be dimensionally stable over the operating temperature range. Where the valves having seats and
back seating facility should
stellited hard facinf or other hard facing material. Bonnets and valve covers shall be bolted in position and not screwed. Other than for main turbine stop valves, isolating valves for steam services should normally be of the parallel slide or pivoted wedge gate type. Parallel slide, butterfly or gate valves may be used for air, water services, and sluice valves for low head applications. Parallel slide or gate valves should be such that the bore of the fully open valve is unobstructed by any part of the gate. Valves operating under vacuum conditions may be of the wedge or gate type with glands and seating rings water sealed. Diaphragm valves shall be used for services carrying chemicals or aggressive fluids, and also for seawater services. Any valve is designed for one directional flow shall have an arrow mark embossed or cast on the valve body clearly indicating the required flow direction. All valves, unless otherwise approved or specified, shall be of the external rising spindle type. Any gear or bevel wheels used to transmit motion shall be of cast steel or approved quality cast iron with machine cut teeth. Special attention shall be given to the operating mechanism and correct lubrication of all valves to ensure a minimum of maintenance and ease of operation.
6.30-25 KHABAT TPP UNITS 1&2 - VOLUME I
All valves shall be provided with stainless steel plate labels or nameplates and stainless steel wire. These labels shall include in the inscription a valve “name”, abbreviated description of the valve duty and a unique plant reference number from the flow diagram or P&ID for the valve. The valve-numbering scheme to cover the complete Contract works shall be agreed with KNOC. After approval of the numbering scheme, the Bidder shall submit a valve schedule to cover the Contract works. The scheduled details of each valve shall include the valve number, its title as it appears on the valve label, the nominal size of the valve, its design pressure and temperature, the Manufacturer’s name and model number and a brief description of the valve materials. The valve list, valve drawings and the operating and maintenance manuals shall be submitted for information by Bidder. Valves operating under vacuum conditions for all DN65 & above valves, DN50 & smaller MOVs, and all control valves shall be water sealed. All necessary sealing water piping shall be provided. When the over pressure reliving devices is indicated in P&ID, the valves shall be provided with approved means of preventing an accumulation of high pressure between discs in parallel slide valves and wedge gate type. When a differential pressure occurs across a closed valve approximately equal to the pressure rating of the valve at the operating temperature, the valve shall be provide with a pressure equalizing bypass. Double block valve shall be used on all drain, vent and instrument connection piping with pressure-temperature rating of ASME class 600 and above All valves for ASME class 600 and higher shall have the pressure seal bonnet or cover type.
6.30-26 KHABAT TPP UNITS 1&2 - VOLUME I
For parallel slide gate valves, overpressure protection shall be furnished for discharge of entrapped water. Especially, overpressure protection for parallel slide gate valves of BFP discharge, the BFP minimum flow, feedwater heater inlet & outlet, bypass and economizer inlet shall have external pipe with small valve After contract, the bidder should submit valve list based on P&ID 2)
Valve materials Unless specified otherwise, the following requirements for valve materials shall be fulfilled.
Service
Fuel oil
Type
Body
Trim
Remarks
Ball (trunnion
Cast or forged
SS ball 316.L of
Top/Bottom
mounted)
steel ASTM 216
ENP
entry
Gr. WCB or A350
- welded ends
LF2
DM water
Diaphragm/stainles
Cast, forged
s steel
steel/stainless
SS.316 L
Flanged ends
Steel
Service water
Gate
Cast/forged steel
13% Cr/SS 304
Flanged ends
Fire water
Gate
Cast/forged steel
13% Cr/ SS 304
Flanged ends
Service air
Ball
Hot dip
13% Cr/ SS 304
Screwed or
galvanized cast
flanged ends
steel
Instrument air
Ball
Hot dip
13% Cr/ SS 304
galvanized cast
Screwed or flanged ends
steel
Chemicals
Diaphragm
Suitably lined
Flanged
6.30-27 KHABAT TPP UNITS 1&2 - VOLUME I
steel
Chilled water
3)
Gate/ball
Cast/forged steel
13% Cr/SS 304
Flanged
Drain, vent valves and traps Except for fuel oil piping all low and high-pressure drain valves shall be of a regulating type. For gas and gas oil service only ball valves shall be used. All material shall be resistant to all chemicals commonly used for acid pickling of the piping system. Double isolation valves shall be provided on vents and drains of systems where the maximum operating pressure is 25 bar g or above, and for all pressures on hazardous services To drain the compressed air lines of condensed water and moisture suitable traps of the thermostatic-thermo-dynamic types shall be installed.
4) Non return valves All non-return valves shall be provided with means of draining the space between the valve and its adjacent isolating valve. The design shall preclude the possibility of the valve jamming in the open position or the effect of solid particles settling-out in dead spaces within the valve should be recognized in this respect. Unless otherwise noted, non-return valves should be rapid closing. Power assisted closing is acceptable where necessary for rapid shut-off. For large non return valves on air and water services, consideration shall be given to the consequences of valve slam and the possible requirements for a hydraulic shock absorber to minimize the slam effects.
5)
Butterfly valves Butterfly valves shall have bodies of either the flanged or lugged wafer type at pipe size is larger than DN 300mm. 6.30-28 KHABAT TPP UNITS 1&2 - VOLUME I
The actuator and manual gearbox shall be mounted direct to the valve body, No actuator loads shall be transmitted to the piping. If the valve is designed for one directional flow, a flow arrow shall be cast or embossed in a prominent position on the valve body to indicate that direction. The valve must be capable of positive shut off in both directions against full system pressure. The seating of the disc must not be passing through the shut position. If the valve body is rubber or plastic lined, the lining should be fully bonded. Internal shaft bearings must be capable of operating dry, that is, not dependent on the presence of the pumped fluid.
6) Safety and thermal relief valves All sections of piping which can be subjected to pressure beyond the design value, e.g. due to change in temperature shall be provided with thermal relief valves. If the piping downstream of a pressure reducing valve is of a lower design pressure then a pressure-relief valve shall be provided on the outlet side of each reducing valve capable of exhausting the maximum discharge of the reducing valve without undue build-up of pressure on the low pressure side. The discharge from the relief valve shall be led to a safe location. Pressure gauge and thermometers shall be provided up-stream and downstream of reducing valves. Valves shall have been certified as acceptable by relevant codes and standards for the service and duty intended. The valves shall be high capacity, flat seated, reaction type with adjustable reaction rings, attaining full lift, spring loaded on top and having a maximum blow down of 4% of the set gauge pressure and have flanged ends at inlets and outlets. Number, individual capacities, and set pressures shall be such as to exceed the minimum requirements of all relevant codes.
6.30-29 KHABAT TPP UNITS 1&2 - VOLUME I
Where multiple valve arrangements are employed the valves shall have a combined flow rate equal to or more than 100% of the maximum flow rate. The actual pressure at which the valve is to lift shall be clearly marked on the valve. Valves shall be equipped with lifting levers. Test gags shall be furnished for hydrostatic testing. Valves shall be factory set for pressure. A spare set of reaction rings shall be provided for each valve. Great care shall be taken in routing the outlet pipe-work to ensure that the point of exit is not liable to cause a safety hazard. Encased or bellows type relief valves shall be used if there is a build up of back pressure on the discharge side and to prevent leakage. The valves shall have a test certificate issued by the manufacturer with inspection authority approval and shall be verified by site test. 7) Pressure reducing and control valves All pressure reducing and control valves shall be of an approved type and shall be perfectly stable, quiet and free from vibration in operation when pressure reducing any flow up to the maximum flow, and shall be suitable for continuous use at the operating temperature. If the piping downstream of a pressure reducing valve is of a lower design pressure then a pressure relief valve shall be provided on the downstream (outlet) side of each pressure reducing valve which shall be capable of exhausting to atmosphere the maximum discharge of the reducing valve without undue build-up of pressure on the low pressure side. The discharge from the relief valve shall be led to a safe point.
Pressure and temperature
gauges shall be provided upstream and downstream of the reducing valve. All control valves shall have a sufficient overload range. At full load and normal operation, the control valves shall be 70-80% open. Valves shall be sized for flow requirements taking into account the appropriate CV factor. 6.30-30 KHABAT TPP UNITS 1&2 - VOLUME I
Control valves for pressures over 25 brag shall be preferably single seat or cage type valve, with a body of forged steel with flanged end connections, and pressure sealing bonnet. Valve class and material shall take into account pressure-temperature rating. Cast iron bodies for control valves will not be accepted. Control valves, independent of their type, shall have a tight shut-off as per the applicable Standards. With the exception of high temperature services, all control valve gland packing shall be of the self lubricating Teflon type. Inner valve trims shall be selected to suit best the process requirements. Inlet/outlet isolating and bypass valves adequate for full flow shall be provided for control valves. Manufacturer’s shop test certificates shall be furnished for the hydrotest of control and pressure reducing valve bodies and for the leakage rates across control valve seats. Valve characteristic curves shall be provided for each type and size of valve. 8) Float valves Float valves should be of the equilibrium ball float type. Floats shall be of a stainless steel. All operating rods, guides, brackets and covers shall be of non-ferrous material. Float valves operating in liquids other than fresh water shall be of materials to the KNOC’s approval. 9) Power oerated valves (Motor Operated or Pneumatic Operated valves) All motor operated valves shall be fitted with both hand and motor operating gears. Where a bypass valve is provided and this by-pass has to be operated each time the main valve is operated then this also shall be arranged with both hand and motor operating gears interlocked to ensure that the bypass 6.30-31 KHABAT TPP UNITS 1&2 - VOLUME I
valve is opened before the main valve. Each valve shall be fitted with limit switches for automatically stopping the motor when the valve gate has reached the “fully open" or "fully closed" position. The motor shall be placed in such a position relative to the valve that there is no possibility of a leakage of liquids or corrosive gas from the valve joints into the motor or control equipment. All power operated valves shall have position indication in the CCR. The hand operating and motor operating mechanism shall be interlocked in such a way that the hand operating mechanism must be disconnected before the motor can be started. Valves shall be provided with seating control, and for small valves, a slip clutch or other torque limiting device shall be incorporated in the motor drive.
Torque limiting or other devices shall be provided to prevent damage to the mechanism in the event of jamming of the driven device. All powered valve or damper mechanisms shall be provided with accurate indication of the position of the driven device. Electrically operated devices may be provided with integral or separate switch control equipment in accordance with the requirements of the control and instrumentation specification. Provision shall be made for the inclusion of interposing relays and volt free contacts to suit modem control systems, including digital control systems. Direct solenoid operation of valves shall comply with the control and instrumentation section of the specification. Reversing contactors and limit switches, used to control electric power driven mechanisms, shall be robust and have proven reliability by both type test and commercial operation.
6.30-32 KHABAT TPP UNITS 1&2 - VOLUME I
10)
Valves for demineralized water systems Valves for the demineralized water systems shall be of the diaphragm type, either rubber lined cast steel or stainless steel.
11) Valves for fire protection and fire safe service Valves for fire protection and fire safe duty shall be of designs specifically designed for the service and capable of receiving regulation approval; e.g. UL, FM etc. 12) Valves for water, drain and air services All valves for water, drain and air services shall be of a make and design with materials of the internal parts all to the approval of the KNOC Sealing between the disc and body of butterfly type valves shall be renewable metal to rubber facings secured to the disc and body in an approved manner.
13) Valves for gas services Valves shall be trunnion mounted ball valves, fire safe to API 607 and provided with antistatic device which shall ensure electric continuity between the ball stem and the body of the valve. No aluminium or zinc alloys or similar low melting material shall be included in their construction. Valves up to 50 mm in size may be of the non-lubricated type, valves greater than 50 mm in size shall incorporate design features that enable lubricant to be injected under pressure between the plug and body whilst the valve is in service. All valves shall incorporate sliding sealing surfaces such that further movement of the closing part is provided after gas shut-off. All valves shall provide reliable tight shut-off and be capable of easy operation after long periods in one position.
14)
Valves for oil services All valves intended for fuel oil or lubricating oil services shall be of cast or forged steel construction with flanged, butt weld, screwed or socket-welded 6.30-33 KHABAT TPP UNITS 1&2 - VOLUME I
ends. Welded on flanges will not be acceptable. All valves shall be fire safe and shall be provided with suitable features in the valve to ensure electrical continuity between the valve stem and the body of the valve. No aluminium or zinc alloys or similar low melting material shall be included in their construction. All valves shall provide reliable tight shut-off and be capable of easy operation after long periods in one position. 6.30.9 1)
Insulation and lgging General The Bidder shall furnish and install insulation for all piping, ducting, vessels and equipment which could have a surface temperature of 60oC or higher. The material shall comply with the following standard specifications or equivalent for mineral fiber: Pipe cover
ASTM C547-95
Wired mats
ASTM C592-97
Block and board
ASTM C612-00
Density (general)
ASTM C612-00
The design value of radiated heat for insulation material shall be as follows: -. Radiated heat : Not more than 837 kJ/m2h -. Ambient temperature : 30°C -. Wind Velocity : 2 m/sec Thermal insulation shall refer to the supply and application of all heat insulation materials together with all necessary associated materials such as fastenings, vapour barriers, jacketing cements, adhesives, etc., which are used as insulating materials for piping, vessels, ductwork and equipment for the purpose of reducing heat loss, prevention of condensation and for personnel protection. All insulation materials for hot application shall be of inflammable, compatible with the surface being covered and shall not cause corrosion of the covered material. All insulation material shall be chemically inert. Asbestos insulation material is not acceptable. 6.30-34 KHABAT TPP UNITS 1&2 - VOLUME I
Insulation for condensation prevention shall be applied to equipment, plant, piping at temperatures below the maximum dew-point where condensation could form to the detriment of plant structures or equipment or cause discomfort to operating personnel. Insulation immediately adjacent to hot surfaces shall be capable of withstanding the full
temperature conditions
without
deterioration or
breakdown of the material and due allowance shall be made for expansion. The type and thickness of insulation materials used shall be entirely suitable for the particular application and shall be sumitted by Bidder. Calcium silicate or mineral fiber shall be used for insulation of hot surfaces of indoor pipes and perlite (water repellent type) for insulation of surfaces of outdoor pipes unless otherwise approved by KNOC. Sprayed on ''asbestos free" insulation shall be provided on irregularly shaped items of equipment. The type of jacketing shall be capable of withstanding the site atmospheric conditions without surface deterioration. All insulation shall be covered with more than 0.3mm aluminum sheets jacket for piping and vessels. Where aluminum sheeting is used, provisions must be made to avoid any electrolytic action. Jacketing fixing devices shall be of an approved non-corrodible material. All outdoor insulation shall be completely weather tight sealed, in particular against heavy rain. All joints in aluminium sheeting shall have a rolled edge to prevent water ingress by capillary action. Piping to be placed in trenches should be covered with insulating materials held with galvanized woven wire mesh. Over the mesh, a coat of refractory cement shall be applied and the whole shall be covered with water proof paint.
6.30-35 KHABAT TPP UNITS 1&2 - VOLUME I
The Bidder shall submit a list of the materials he proposes to use, their thermal emission calculation for the operating temperatures of each application, the thickness and density of each material. Insulation shall be applied in a manner which will allow withdrawal of the removable part without damage to such sections or to adjacent insulation. Equipment nameplates mounted on brackets extended from the body shall be exposed ready for identification. The insulation and cladding of the items requiring maintenance shall be designed to permit quick and easy removal. During the application of insulation the Bidder shall protect the adjacent plant, buildings and floors from damage. In the event of damage the Bidder must make good at his own expense. In mixing insulation or covering compounds, salt or brackish water shall not be used. Wherever insulation is necessary only for the protection of personnel, it shall be applied around that portion of the pipeline of the length that is located within 2.10 m above the passage way floor, or within 1.20 m horizontally to the side or at the end of any floor, platform, walkway, stair or ladder. After contract, the bidder should submit piping and equipment insulation list based on P&ID
2)
Methods of application The insulation shall generally be installed in accordance with the recommendations of an approved international standard. Piping and equipment must be clean, dry and free from grease, dirt, loose rust or scale before application of insulation materials.
6.30-36 KHABAT TPP UNITS 1&2 - VOLUME I
On vertical or near-vertical piping all insulation shall be supported in position by means of metal rings, part rings, studs or cleats at intervals not more than 3.5m. On flat, or large curved surfaces, the insulation material shall be supported by cleats or similar attachments welded or screwed to the surface being insulated. Preformed materials shall be applied for the insulation of pipe work but where the pipe size is too large for preformed material, radiused and bevelled lagging sections shall be applied. The preformed insulation materials shall be secured to pipe work by means of circumferential tie wires. The wire material shall be corrosion resistant and if the overall finish is to be aluminum sheet the wires must be either of aluminum or plastic coated metal. Where flanges and flanged valves are to be insulated, the pipe work insulation must be terminated short of the flanges to enable easy withdrawal of the flange bolts without damage to the insulation. Flanges and valves shall be insulated with aluminum boxes lined with preformed rigid or flexible insulating material which is arranged for easy removable for inspection or maintenance without disturbing the insulation of adjacent pipe work. There shall be no direct contact between the aluminum of the box and the insulated metal surface. Glands of all valves shall be left out of the insulation box. Thermowell bosses, pressure tapings and equipment nameplates shall be left out of insulation. The piping and equipment shall be completely insulated before the commencement of the experimental operation, but the final lagging of all valves, fittings, and pipe flanges shall not be carried out until the system has been continuously under operating pressure and temperature for at least two (2) days, so as to enable the joints to be inspected.
3)
Finishes and appearance cladding Metal cladding shall be provided to give a neat, smooth external finish and to 6.30-37 KHABAT TPP UNITS 1&2 - VOLUME I
protect the insulation of all pipe work, ducting, vessels and casings. Metal cladding shall be of aluminium or galvanized steel unless otherwise agreed by the KNOC. Areas where workman occasionally walk over shall be provided with insulation strong enough to support a man’s weight. The insulation layer in this region shall consist of a material to withstand walking on such as for example a monoblock or similar material. The Bidder or shall identify such areas and include this in his insulation schedule.
6.30-38 KHABAT TPP UNITS 1&2 - VOLUME I
6.31
Elevator
6.31.1
Scope
6.31.1.1
General This specification states the conditions and requirements for for procurement, delivery to jobsite, installation, start-up, for perfect operation, including two(2)elevators its accessories and equipments in the boiler buildings and two(2)elevators its accessories and equipments for the FGD absorber area at khabat district of Iraq (150MW Ｘ2Units).
6.31.1.2
Description of service A.
A passenger-freight electric elevator with vestibules shall be furnished to serve the major level of Boiler building and FGD absorber area
B.
This elevator shall be designed and constructed according to the following indoor operating condition :
6.31.1.3
1) Temperature
: 4 ~50 deg.C
2) Pressure
: 760 mmHg
3) Relative Humidity
: 12~92%
Design condition A.
Boiler building 1) Capacity 2) Speed
B.
: 60 m/min.
FGD absorber area 1) Capacity 2) Speed
6.31.1.4
: 2.0 Tons (30persons)
: 1.5 Tons (20persons) : 60 m/min.
Performance guarantee The Bidder warrants that the equipment shall be free from liens and defects in design, material, workmanship, and title, and shall conform in all respect to the terms of this specification and to the applicable drawings issued for manufacture, and shall be new and of the best quality, unless otherwise specified.
6.31.2 6.31.2.1
Design and consturction conditions General 6.31-1 KHABAT TPP UNITS 1&2 - VOLUME I
A.
Elevator systems shall be designed and installed according to information provided on the design drawings, manufacturer's standards, and the applicable regulation of ASME A 115.1.
B.
The elevator system shall be designed so as to ensure continuously safe, reliable and economical operation without vibration and noise.
6.31.2.2
Hoistway equipment A.
A guide rail for car and counterweight, machine support beam and braces shall conform to ASTM A 36.
B.
Counterweights shall be steel plate weights restrained within a steel frame and the frame within its guide shoes, and shall be equal to the weight of the complete elevator car plus 45 to 50 percent of the specified load pacity.
C.
Hoist and governor ropes shall be wire ropes for elevator and shall conform to ASME A 115.1. The safety factor of the wire ropes shall be not less than 10.
D.
The machine shall be rigidly mounted on supports with the necessary bearing plates anchored onto the structure. Bearing plates shall be equipped with noise isolators approved by the KNOC.
E.
The leveling device for cars shall be the "two-way automatic maintained" type.
6.31.2.3
Car and hoistway doors A.
Car and hoistway doors shall be motor-operated and equipped with safety device which will prevent car travel while doors are open. Car and hoistway doors shall be made of stainless steel, not less than 1.5mm.
B.
Door sills shall be manufacturer's standard extruded aluminum with groover surface. Hoistway door sill shall be provided with suitable anchors for attachment to the floor construction.
C.
Doors shall be equipped with retractable safety strip at leading edge which shall enable the door to open automatically when obstructed during closing cycle, and shall resume closing when obstruction is removed.
D. 6.31.2.4
A door panel shall contain sound-deadening material(glass wool). Elevator car
A.
The car frame shall be rigid structure of structural steel members.
6.31-2 KHABAT TPP UNITS 1&2 - VOLUME I
B.
The car platform frames shall be constructed entirely of steel, with necessary reinforcement.
C.
The car enclosure shall be made of stainless steel, not less than 1.5mm.
D.
The top of the car shall provided a work platform, accessible from the car through an exit hatch. A switch shall prevent the car from travelling while the hatch is open.
E.
The convenience receptacle shall be provided on top of the car and underneath the car platform for maintenance.
F.
Exposed hardware, such as control panel, handrail, telephone cabinet door, and protective pad hook shall be stainless steel, the type SUS 304.
G. The car floor shall be made of steel plate or checkered steel plate as specified in design data, not less than 4.5mm. 6.31.2.5
Motor A.
The motor shall be reversible type designed for elevator service, capable of operating the elevator's specific load and speed without exceeding the NEMA Class B temperature rise above 40 deg.C maximum ambient temperature.
B.
The motor insulation shall be Class "F" or better in accordance with the NEMA standard. The motor shall have antifriction bearings, Alemite Pin Type Grease Fittings and spring type grease relief fittings.
C.
The primary voltage of the motor set shall be 460V, 3 phase.
D.
The locked rotor current of AC motors shall not exceed 650% of full load current when tested at rated voltage and frequency. Motors shall have a safe stalled rotor time which is longer than the accelerating time.
E.
The sets shall start automatically by activating the car button or the emergency service button and shall continue to run for a predetermined time interval after the last call has been answered. The elevator controller shall be Variable Voltage Variable Frequency type.
F. 6.31.2.6
The details of motors shall conform to manufacturer’s spec. Wiring
A.
All necessary wiring for proper operation of the equipment, including the power and lighting receptacles, shall be furnished and installed by the Bidder.
B.
All control and instrumentation wiring shall have a flame retarding braid covering. 6.31-3 KHABAT TPP UNITS 1&2 - VOLUME I
6.31.2.7
Car lighting and ventilation A.
Interior car lighting shall be the combination of exhaust ventilation fan and light fixture.
B.
Lighting of the car shall be uniform illumination, not less than 100 Lux measured at the car floor.
C.
The Bidder shall provide a dry type transformer in relay panel to step down the 480V source for the lighting and ventilation power supply, 220V AC 1 phase, 60 Hz.
D.
Ventilation shall be provided by a one speed motor driven, fan. capable of delivering 17 m3 of air per minute.
E.
All elevator shall have a self-contained battery operated emergency interior lighting fixture which shall conform to all requirements of ASME A 115.1. This light comes on automatically in case of normal lighting power failure. It shines with a brightness of 1 Lux(at the distance of the floor of car) for 30 minutes or more.
6.31.2.8
Car interphone and telephone A.
The Bidder shall furnish and install at the jobsite a Interphone, a Interphone amplifier junction box, and wiring between these two devices. The KNOC shall furnish wiring between the car and the main control room. The Interphone shall be mounted in the elevator car interior and the machinery room. The Telephone shall be furnished and installed in the elevator car interior and the main control room. The amplifier junction box shall be mounted on the top exterior of the elevator car.
B.
The Bidder shall provide a wireway between Interphone enclosure and the Interphone amplifier junction box mounting location.
6.31.2.9
Operation and control A.
Operation and signals shall be pushbutton system of selective and collective automatic. Operation shall include a top-of-car operating device, control panel in the car and emergency automatic control.
B.
Car control panel shall be flush-mounted, consisting of a bank of buttons numbered to the corresponding landings served, CLOSE DOOR and OPEN DOOR and OVER-RIDE buttons, emergency button to be connected to an alarm bell, located in control room.
C.
Each landing car call button and numbered buttons on car control panel shall contain a light which shall illuminated until the call is answered. 6.31-4 KHABAT TPP UNITS 1&2 - VOLUME I
D.
An electric multilight position indicator shall be furnished and installed in the car, directly over the entrance. The position of the car in the hoistway shall be indicated by illumination of the numeral corresponding to the floor at which the elevator is stopped or passing.
E.
Adjustable time limit relay shall be provided to hold the door open for a period of 10 to 30 seconds at landings, to enable passengers or freight to enter or leave the car. Pressing the car button for other landing before this time period elapses shall not cause the car to start until the car and hoistway doors are closed. Only when the control panel has answered the farthest call in this interval, a car button call register to permit the car to travel in the opposite direction or a landing button call can register for opposite direction of a landing button call can register for opposite direction of travel. After the control panel answers all calls the car shall automatically return to the "home landing" as designated by the KNOC.
F.
The emergency stop-switch in the elevator interior shall switch off the power to the driving-machine motor and the brake, and stop the elevator in emergency.
G. The key-operated "override" switch shall allow a passenger to operate the car without regard to landing calls. "Override" switch shall be a keyed switch in the car with key type as approved by the KNOC. This switch, when activated shall initiate the following services: 1) The elevator shall be operated only by pressing buttons in the control panel including the CLOSE DOOR and OPEN DOOR buttons, and shall not respond to landing calls. 2) Constant pressure on the CLOSE DOOR button shall close the doors, Releasing the pressure on the button before doors are fully closed, shall cause the doors to reopen. 3) Changing travel call shall be accomplished by momentary reactivation of the keyed switch. 4) Car shall travel and stop at the call landing. 5) Once fully opened, doors shall remain open until closing is initiated by pressure on the CLOSE DOOR button. 6) Elevator shall be restored to normal operation when deactivating the "override" switch in the car.
6.31-5 KHABAT TPP UNITS 1&2 - VOLUME I
H.
For each elevator a key-operated emergency "override" switch shall be provided at the designated "home landing" level. This switch shall be adjacent to the landing cal button.
I.
When the "override" switch is activated, the car control panel shall cancel all calls, the car shall return nonstop to the designated landing, doors shall automatically open and remain open until closed by pressing the CLOSE DOOR button in the car control panel.
J.
Electrical position indicator(s) shall be furnished and installed at all floors directly over the entrance. The position of the car in the hoistway shall be indicated by illumination of the numeral corresponding to the floor at witch the elevator
car is stopped or passing. The hall position indicator frame
shall include an illuminated "override" indicator marked to read "EMERGENCY", This position shall illuminate when any emergency calls, emergency operations, emergency stops occur, or car activated from the control panel in the car, or at designated "Home Landings," and shall remain illuminated until deactivation and return to normal operation. K.
After answering all calls, the car shall return and park at the designated "Home Landing".
L.
At all elevators an 8 ohm paging speaker shall be installed in the cars for connection to the public address system. The speaker shall include a 70 volt matching transformer.
M. A flush-mounted plate with necessary push buttons shall be provided at each landing. All plates shall contain an illuminated fixture that will indicate when the car is in service. N.
Each elevator shall be equipped with a seismic triggering device, to operate in conjunction with the elevator control system and prevent operation of the elevator during an earthquake. The earthquake system shall be activated by a seismic switch or derailment device. Upon acting of the earthquake system, the cars shall operate as follows : 1) If the car in motion,
all car calls shall be cancelled, and the car shall
be proceeded to the next floor in the direction of travel and stop. 2) If the car is stopped at a floor, all car calls shall be cancelled, and the doors open and remain open. 3) Elevator shall not return to normal operation until the seismic switch or derailment device is reset.
6.31-6 KHABAT TPP UNITS 1&2 - VOLUME I
6.31.2.10 Controller and relay panel A.
The controller and relay panel shall be of the full magnetic type including all apparatus necessary to control starting and stopping of the elevator and to accomplish the specified operation. Starters are to be provided and arranged to stop the motor in the event one starter fails to open.
B.
AC magnetic contactors shall be rated in accordance with KS C 4504. The life expectancy of the magnetic contactor and auxiliary relay shall not be less than the following values. 1) Magnetic contactor : 100,000 electrical operations. 2) Auxiliary relay
: 5,000,000 mechanical operations. 1,500,000 electrical operations.
C.
Thermal overload relays of the manual reset type shall be provided for protection of the motor.
D.
Control panel doors shall be 2.3mm thick steel sheet panel with spongy edge side.
6.31.2.11 Safety devices A.
Oil buffer shall be used with necessary blocking and supports provided. Detail construction and requirements for buffers shall conform to ASME A 115.1
B.
The governor shall be designed to meet the overspeed switch set for tripping for the power supply to the elevator motor when the rated car speed is exceeded.
C.
Wedge shall be mounted on the bottom members of the car platform and actuated by a governor mounted over the hoistway. When the cage begin to travel at excessive speeds, the governor activates these wedge brakes, which grasp the guide rail and bring the cage to a safe stop.
D.
Limit switches(normal terminal stopping device) shall be provided and arranged to slow down and stop the car automatically, at or near the top and bottom terminal landing.
E.
Final limit switches(final terminal stopping device) shall be provided and arranged to cause the electric power to be removed automatically from the elevator driving-machine motor and brake when the car has passed a terminal landing.
6.31-7 KHABAT TPP UNITS 1&2 - VOLUME I
F.
Load weighing devices which will prevent operation of the elevator shall be installed in the car. This device sounds a buzzer when the load on the elevator platform is in excess of 110% of the rated load.
6.31.2.12 Coating A.
All surfaces to be painted shall be thoroughly cleaned of all mill scale, rust, grease and other foreign materials.
B.
Stainless steel surface shall not be painted.
C.
Car exterior shall be coated with manufacturer's standard finish.
D.
Guides, counter-weights and other rough steel or iron surface shall be painted with manufacturer's standard primer. Electrical equipment, controls and motors etc. shall be coated according manufacturer's standards.
Dimensions of all major components shall be checked in accordance with drawings approved by the KNOC.
6.31-8 KHABAT TPP UNITS 1&2 - VOLUME I
6.31.3
Elevator Data
ELEVATOR DESIGN DATA for Boiler Building and FGD Absorber area TYPE OF SERVICE
Passenger and Freight
CONTROL SYSTEM
VVVF(Variable Voltage Variable Frequency)
NO. OF UNIT
Set
SYSTEM
PERFORMANCE OF UNIT CAPACITY
2.0 Tons (30 persons) and 1.5 Tons (20 persons)
TRAVEL DISTANCE NO. OF STOPS PIT SIZE TYPE OF OPERATION Selective Collective Automatic DOOR TYPE
2 Panel Horizontal Sliding
DOOR OPENING SIZE HOISTWAY SIZE POWER SUPPLY LIGHTING CAR INTERNAL SIZE CAR ENCLOSURE
Stainless Steel (Hairline Etching Finish)
CAR FLOORING
Checkered Stainless Steel Plate THK 4.5 mm
CAR DOOR
Stainless Steel (Hairline Etching Finish)
LANDING DOORS
Stainless Steel (Hairline Etching Finish)
CAR CEILING
Stainless Steel Sheet and Fluorescent Lighting Through Milk
LANDING SILL
Extruded Aluminum
OPERATION PANEL
Touch Type
POSITION INDICATOR
Digital Type
LANDING BUTTON
Illuminated Type Touch Button
KICK PLATE
Stainless Steel
6.31-9 KHABAT TPP UNITS 1&2 - VOLUME I
7
ELECTRICAL SYSTEM This part of the specification details the requirements for the electrical plant for each of the units and the station auxiliaries, and the criteria against which the equipment shall be designed. The electrical system shall be designed for operation where continuity of supply is the prime consideration. The failure of any one part of the electrical system within the power station shall not result in the total loss of generating capability. Fault studies have been carried out by others, the results of these studies will be made available upon request.
7.1
General
7.1.1
Nominal voltage ratings The following voltage levels will apply:
7.1.1.1
Electrical power AC 132kV ± 10%, 50Hz 3 phase, 3 wires wye AC 6kV ± 5%, 50Hz 3 phase, 3 wires wye AC 400V ± 10%, 50Hz 3 phase, 4 wires wye DC 220 volts, +10% ~ -15% range
7.1.1.2
Electrical power for instrumentation and control AC 230V ± 1%, 50Hz 1 phase DC 220 volts, +10% ~ -15% range
7.1.1.3
Lighting, receptacle and small power AC 400/230V ± 10%, 50Hz 3 phase, 4 wires
7.1.2
Electrical equipment enclosure Unless otherwise specified, Equipment enclosure classes shall be as follows. - Indoors (in air-conditioned clean rooms): IP31 - Outdoors, and indoor areas subject to water spray: IP54 7-1 KHABAT TPP UNITS 1&2 - VOLUME I
or heavy condensation Electrical equipment such as medium voltage (MV) & low voltage (LV) switchgear, motor control centers (MCCs), distribution boards (DBs), etc., shall be installed in the electrical room where provided with HVAC system, except for the equipment to be located outside of electrical room by its purpose or nature. Anti-condensation heater will not be provided for the electrical equipment located in the air-conditioned electrical room. Electrical equipment layout shall be subject to the KNOC’s approval. 7.1.3
Control and selector switches Control switches shall be of the three-position type with a spring return action to a central neutral position. Switches for other apparatus shall be operated by push buttons, shrouded or well recessed in their housings to minimize the risk of inadvertent operation. Each position of the selector switch shall be suitably labeled to signify its function. It shall not be possible at any time to operate any switchgear Equipment from more than one location simultaneously, and suitable lockable selector switches shall be provided to meet this requirement. Particular variations of the above requirements may be agreed by the Owner for the above controls when incorporated on special instrument or control Equipment, i.e., central control room desks and panels, and electrical Equipment cubicles. The contacts of all control and selector switches shall be shrouded to minimize the ingress of dust and accidental contact, and shall be amply rated for voltage and current for the circuits in which they are used.
7.1.4
Switchboards, panels and cubicles Unless otherwise specified, switchboards (switchgears, MCC’s, distribution boards, etc.), panels and cubicles shall be of floor-mounted and free-standing construction and be in accordance with the specified enclosure classification. Switchboards, panels and cubicles shall be rigidly constructed from folded 7-2 KHABAT TPP UNITS 1&2 - VOLUME I
sheet steel of adequate thickness to support the equipment mounted thereon. Switchboards, panels and cubicles shall be mounted on an approved form of anti-vibration mounting whenever necessary. All switchboards, panels and cubicles shall be vermin-proof. All cable entries to equipment shall be sealed against vermin as soon as possible after installation and connecting-up of the cables. All switchboards, panels and cubicles shall be provided with a natural air circulating ventilation system. All control, protection, measurement, metering and indication equipment shall be designed to operate without forced ventilation. The bottom or top of switchboards, panels and cubicles shall be sealed by means of removable gasketted steel plates. Suitable space between the plate and terminal blocks shall be reserved for cable connections and maintenance. Switchboards, panels and cubicles shall be suitably designed to permit future extension wher specified. Instrument and control devices shall be easily accessible and capable of being removed from the panels for maintenance purposes. All switchboards, panels and cubicles whether individually mounted or forming part of a suite, shall incorporate a common internal copper earthing bar onto which all their earth connections shall be made. Suitable studs or holes to the Owner's approval shall be left at each end of the bar for connection to the main station earthing system and possible future extension. All switchboards, panels, cubicles shall incorporate electric heaters capable of providing movement of sufficient heated air to avoid condensation. The apparatus so protected shall be designed so that the maximum permitted rise in temperature is not exceeded if the heaters are energised while the apparatus is in operation. 7.1.5
Indicating lamps and fittings All indicating lamps shall be of a LED type. Lamps shall be easily removed and replaced where possible from the front of the panel by manual means preferably not requiring the use of extractors.
7-3 KHABAT TPP UNITS 1&2 - VOLUME I
The variety of indicating lamps provided shall be rationalised to reduce maintenance and spares requirements. The lamp glasses shall be in the standard colours, red, green, white and amber. Lamps test facilities shall be provided for switchboards, control panels etc., where practical, to enable all lamps to be tested whilst the equipment is in service. Operation of the lamps test facility shall not cause any other device to operate. 7.1.6
Panel wiring and terminal boards
7.1.6.1
General All electrical equipment mounted in or on switchboards, panels and cubicles shall have readily accessible connections and shall be wired to terminal blocks for the reception of external cabling. The insulation of the wiring shall be of a type capable of withstanding the conditions at the site without deterioration. Due allowance shall be ensured for such temperature conditions as may arise within any enclosure. The insulating material shall not assist the spread of fire, i.e., shall not continue to burn once the source of flame is removed. Both ends of every wire shall be fitted with interlocking ring-type numbering ferrules of white insulating material, and engraved in black. Wiring shall be supported using an insulated system which allows easy access for fault finding and facilitates the installation of additional cables. Connections to apparatus mounted on doors, or between points subject to relative movement, shall be made in flexible wires, arranged so that they are subject to torsion rather than bending.
7.1.6.2
Identification of wires The insulated covering of internal wiring in switchboards, panels and cubicles shall be colored or identified by numbering and lettering ingrained in the insulation or ferruling. Where a wire of a multi-core cable passes from one piece of Equipment to another, e.g. from a circuit breaker to a remote control panel, the Supplier shall ensure that the identity of the wire is apparent at both ends by the use of ferruling. Each core of multi-pair wiring shall be identified by color and terminal block 7-4 KHABAT TPP UNITS 1&2 - VOLUME I
identification. Permanent identification of all terminals, wires and terminal blocks shall be provided. 7.1.6.3
Terminals and terminal boards Terminal boards shall have separate terminals for internal and external connections, and not more than two wires shall be connected to each terminal. Wires shall be grouped on the terminal boards according to their functions. Adjacent terminals to which wires of different voltage, polarity or phase are connected shall be separated by a protruding insulating barrier. This requirement also applies to terminals carrying wires of the same voltage but originating from different sources. Sufficient terminals shall be provided to permit all cores on multi-core cables including spare cores to be terminated. Terminals for spare cores shall be numbered and be located at such position to provide the maximum length of spare core. When two lengths of screened cable are to be connected at a terminal block of a junction box, a separate terminal shall be provided to maintain screen continuity. The use of pre-formed factory tested cable connections to field mounted marshalling boxes may be allowed as applicable. All of electrical equipments shall be furnished with 20 percent spare terminals.
7.1.7
Current transformers All current transformers shall comply with IEC 60044-1. CT secondary windings shall be earthed at one point only through an accessible link. The secondary windings shall have a 1 A rating as appropriate. Facilities shall be provided to allow primary injection testing with minimum disturbance to the equipment. The following accuracies shall be used:
Metering
Class 0.5
Instruments
Class 0.5
Differential protection
Class 5P20
Other protection
Class 5P20 7-5 KHABAT TPP UNITS 1&2 - VOLUME I
The minimum burden foreseen for all the type of current transformers for 15kV system and above shall be 30VA. 7.1.8
Voltage transformers All voltage transformers shall comply with IEC 60044-2. For MV applications the primary windings shall be connected through renewable fuses. The secondary winding of all VTs shall be provided with an accessible phase coded fuse or miniature circuit breaker. VT secondary circuits shall be complete and earthed at one point only. It shall not be possible to connect VT secondary circuits in parallel where the VTs are connected to different sections of busbar. The following accuracies shall be used:
Tariff metering
Class 1.0
Instruments
Class 1.0
Protection
Class 3P
The minimum burden foreseen for all the type of voltage transformers for 15kV system and above shall be 30VA. 7.2
Generators
7.2.1
General The generators shall be two pole synchronous machines and shall comply with the requirements of IEC 60034-3. Each generator shall be of an established design having a proven record of reliability for similar applications. The stator and rotor insulation systems shall be to Class 155 (F) in accordance with IEC 62114 but the relevant temperature rises and total temperatures shall not exceed the limits for Class 130 (B). Each generator shall operate satisfactorily in parallel and with the grid system under all normal system operating conditions. In designing the layout of the power station particular attention shall be paid to ensuring free access for the complete withdrawal of each generator rotor. It shall also be possible to remove and reinstate each generator stator with the minimum disruption to adjacent plant and equipment. Any special equipment necessary for rotor and stator handling shall be provided.
7.2.2
Rating and capability Each generator shall have a rated output and capability that shall equal or exceed the output of the steam turbine with valves wide open and with the 7-6 KHABAT TPP UNITS 1&2 - VOLUME I
boiler at overpressure and shall not under any condition, limit the output of the respective generating set. Each generator shall be capable of generating rated active power over the range of power factor from 0.85 lagging to 0.95 leading. Each generator shall be capable of supplying it’s rated output at rated frequency and rated power factor for a voltage range of ±5 per cent at the generator terminals, and shall also be capable of supplying its rated output at rated voltage and rated power factor at a frequency which may vary between 48.5 Hz and 51.5 Hz. The short circuit ratio shall be not less than 0.5. 7.2.3
Generator cooling Each generator shall be cooled by hydrogen or a combination of hydrogen and demineralised water. The hydrogen shall be circulated around the machine by shaft mounted fans, and then cooled by water to hydrogen heat exchangers mounted within the generator housing. The cooling water for the machines shall be supplied from a closed circuit system. Gas coolers shall be arranged in the stator frame so that they can be individually withdrawn with the stator in position. Any apparatus required to withdraw the coolers shall be provided. The coolers shall be sized such that the generator will be capable of 80 per cent rated output with one cooler section out of operation. Auxiliary systems shall be provided according to the requirements of IEC 60034-3.
7.2.4
Gas systems The cooling and scavenging gas systems shall be complete for each generator with all pipework and valves, controls and instrumentation. Bulk gas storage facilities shall be suitably located adjacent to the turbine house. The Bidder shall provide the gas required for operation of the machine up to taking over but the gas supplies after taking over will be provided under a separate contract. A distribution system shall convey the gas to each generator gas control panel where the pressure shall be reduced accordingly. The gas control panel equipment shall automatically maintain the set hydrogen pressure in the casing and correct purity and humidity levels 7-7 KHABAT TPP UNITS 1&2 - VOLUME I
during operation. The gas supplies and storage shall have adequate capacity for successive gas changes and nominal leakage. The maximum hydrogen leakage rate shall be stated in the Tender. The purge gas system shall include a heater to ensure that the temperature of the gas does not cause damage to the generator. The cooling gas system shall include a dryer through which the gas from the generator casing shall be continually circulated. The desiccant in the dryer shall be able to be reactivated with the machine in normal operation. The dewpoint of cooling gas in the stator casing and the gas dryer outlet shall be continually monitored and recorded. 7.2.5
Demineralized water system Where the standard design of generator adopts a demineralised water cooling system for the stator windings, terminal bushings and other components, the system shall be complete with motor driven pumps, fine strainers, ion exchanger, buffer tank, water to water heat exchangers, piping, valves and all measuring and monitoring equipment. Means of measuring cooling gas leakage into the demineralised water shall be provided, together with an alarm to indicate when the leakage exceeds a preset limit. Instrumentation to continuously monitor the oxygen level in the demineralised water shall be provided.
7.2.6
Seal Oil System A. A seal oil system shall be provided for the generator to maintain the hydrogen purity within the generator casing. B. The seal oil system shall be complete including all pumps with drive motors, piping with hangers and supports, pressure switches, storage tanks, traps, valves, main and emergency seal oil pumps and starters, gauges, vacuum treatment system, controls and indicating and alarm devices all as required by the Supplier's standard design. C. All controls and signals(process, equipment status/demand) for the shaft seal oil system shall be constructed and implemented in the turbinegenerator control system(TCMS), and shall be operated by TCMS’s LCD monitor in the main control room. The Supplier shall perform the 7-8 KHABAT TPP UNITS 1&2 - VOLUME I
satisfactory operation of the shaft seal oil system. The Supplier shall provide local cabinet for field instruments and devices. The seal oil system, with the exception of field instruments shall be mounted on a single baseplate and be preassembled in the shop to the maximum practicable extent. Field instruments shall be mounted in the local instrument cabinet. D. Provisions shall be made to maintain integrity of the shaft seal oil system in the event of loss of auxiliary power to the (normal) seal oil pump. E. The method of sealing shall be the same during the shutdown period as for the operating period, and equal precautions shall be taken to prevent hydrogen contamination during both periods. F. The DC powered seal oil pump motor shall be provided with magnetic trip-only circuit breaker and magnetic starter with overloads arranged for alarm. G. A backup emergency oil system which supplies the seals with oil from the turbine bearing oil system shall be provided. 7.2.7
Terminals The line terminals of each generator shall suitable for the connection of isolated phase busbars.
7.2.8
Sliprings and brushgear The generator rotor sliprings and brushgear shall be separately enclosed and fan cooled by air drawn from the turbine house through dry type filters. The warm air outlets of the enclosure shall be arranged so as to avoid recirculation of the cooling air. The ventilation circuit shall be designed so that the cooling air shall flow in an axial direction over the slipring surfaces and eliminate the risk of oil vapour and dust fouling the slipring surfaces. Filters shall be readily accessible for inspection and maintenance. Windows shall be provided in the slipring and brushgear enclosure so that all the brushes can be seen when the machine is in operation. Internal lighting arrangements shall be provided.
7.2.9
Instrumentation and metering 7-9 KHABAT TPP UNITS 1&2 - VOLUME I
Continuously acting rotor winding earth fault and shorted turn fault monitoring shall be provided. On-line condition monitoring equipment shall be provided for the stator winding insulation system. A full description of the proposed equipment shall be provided with the Tender. Resistance temperature detectors shall be three wire Pt 100 type and the minimum requirements for each generator are as follows:
Stator windings - between coils
3 per phase
Demineralized water cooled stator windings - coolant exit
3 per phase
Stator core
3
Stator teeth
3
Cold gas from coolers
1 per path
Warm gas to coolers
1 per path
Inlet cooling water
1 per path
Outlet cooling water
1 per path
Dual type resistance temperature detectors shall be provided for the bearing metal and also bearing outlet oil temperature measurement on each bearing. The leads from the temperature detectors shall be brought out in a safe manner to metal clad terminal boxes fitted in accessible positions. Flexible connections should be used to avoid damage to the leads by vibration. The boxes shall have suitable labels to enable the individual detectors to be readily identified. 7.2.10
Accessories Shaft earthing of the generator shall be provided, together with the means of monitoring shaft voltages and bearing insulation. All necessary special tools for assembling and dismantling of the generator, including jacks, slings, lifting beams, skids, shaft extensions, shall be provided.
7-10 KHABAT TPP UNITS 1&2 - VOLUME I
7.3
Excitation System and Equipment Each generator shall be provided with a static excitation system. The system shall utilize a three phase fully controlled thyristor bridge rectifier energized from the machine terminals through a suitable transformer. The system shall comply with the requirements of the relevant IEC standards. The excitation equipment shall operate reliably and shall not impose restrictions on the availability of the generator due to excitation equipment faults or malfunctions. The excitation system shall be capable of supplying the specified ceiling excitation for a period of not less than 10 seconds following full load operation with the generator subsequently returning to full load operation The excitation system shall be complete with all the necessary control, monitoring and protection equipment to enable operation from the central control room. The rectifier and AVR equipment shall be located in an air conditioned enclosure, adjacent to the respective turbine unit. Cubicles shall have a minimum degree of protection of IP54.
7.3.1
Rectifier A fully controlled three phase, six pulse thyristor bridge rectifier shall be provided. Spare capacity shall be built into the equipment to allow uninterrupted operation during the period between generating set overhaul outages. Any rectifier failures during this period shall not place a restriction on steady state or transient performance. The design shall allow easy replacement of thyristors and fuses if used. Where forced air cooling is considered necessary, main and standby fans shall be provided. To reduce the risk of bearing damage in stationary fan units, both fans shall either run continuously or be subject to cyclic operation. Hot air shall be ducted outside of the equipment area. The cooling air shall be drawn into the rectifier cubicles through dry type air filters. The position of air filters shall be chosen to achieve maximum operating time between filter cleaning or replacement. An alarm shall be given when the air pressure drop across the filter has reached the maximum permitted value. Alarm and trip facilities shall be provided to cover failures of the cooling 7-11 KHABAT TPP UNITS 1&2 - VOLUME I
system. 7.3.2
Excitation transformer The excitation transformer shall be of the three phase, cast resin type, suitable for indoor installation and shall comply with the requirements of IEC 60076, IEC 60146 and IEC 60726. The transformer shall be equipped with a two stage temperature alarm relay with volt free contacts. The operating temperature of the two stages shall be individually adjustable. The transformer shall be housed in a naturally ventilated steel enclosure, located below the generator main connections in the turbine hall.
7.3.3
Control equipment The excitation system shall include a continuously acting automatic voltage regulator, with no dead bands. The regulator shall have dual automatic channels together with manual control facilities for commissioning and maintenance. An auto following control function shall be provided to ensure smooth transfer between automatic channels. The voltage reference signals for the two automatic channels shall be provided from separate sets of VTs. Local and remote set point control shall be provided for automatic control, with local control provided for manual operation. Appropriate auto/manual changeover facilities shall be provided. Limiters shall be provided for underexcitation, overexcitation and overfluxing. Each limiter shall have adjustable settings. Circuits shall be provided for reactive load sharing with other machines and line drop compensation. A power system stabilizer and a reactive power controller shall also be provided.
7.3.4
Field suppression Field suppression equipment shall be provided to rapidly reduce the excitation of the generator to zero in response to a trip signal or a circuit breaker open signal. The field suppression equipment shall operate independently from the excitation control equipment. It shall be housed in a cubicle and form part of the excitation equipment cubicle suite.
7.3.5
Connections Connections between the generator rotor brushgear terminals and the field 7-12 KHABAT TPP UNITS 1&2 - VOLUME I
suppression equipment shall be run as cables or solid bars. Adequate support shall be provided to prevent conductor movement under both normal and fault current conditions. Positive and negative conductors shall be run close together to minimize stray magnetic fields. Where solid bars are used adequate insulation to earth and between poles shall be provided. Bars shall be adequately supported to prevent natural frequency vibration. If cables are employed they shall comply with the requirements detailed elsewhere in this Specification. The connections between the generator line terminals and the excitation transformer shall be run in a phase isolated bus system compatible with that being provided for the generator main connections. All connections between the low voltage terminals of the excitation transformer and the rectifier shall be in single core cables. Adequate support shall be provided to prevent conductor movement under both normal and fault conditions. Cable runs shall be arranged to ensure that all phases have the same impedance in order to prevent current unbalance in the rectifier phases. Cables shall comply with the requirements detailed elsewhere in this Specification. Connections shall be of sufficient cross section to carry the maximum steady state excitation current continuously, and the maximum field forcing current for 10 seconds without exceeding permitted temperature rise. 7.3.6
Monitoring and protection Monitoring equipment shall be provided to check conduction in each thyristor of the bridge rectifier equipment. Protection equipment shall be provided for the excitation system equipment to detect the following:
Excitation transformer primary and secondary side failure.
Short circuit across the excitation system output.
Failure of automatic voltage regulator channel 1.
Failure of automatic voltage regulator channel 2.
Insufficient rectifier capacity available.
7-13 KHABAT TPP UNITS 1&2 - VOLUME I
Sustained excitation in excess of equipment continuous rating.
Loss of field, or sustained low excitation.
Loss of coolant supply to, or dangerously high temperature in the equipment.
Excitation circuit earth fault.
As a general rule the response of the protection equipment shall not initiate a trip of the field circuit breaker if the synchronizing circuit breaker is closed. 7.4
Generator Main Connections and Neutral Earthing
7.4.1
Function The connections between generator line terminals, unit auxiliary transformer and generator transformer shall be carried-out by means of natural air cooled isolated-phase bus duct, where the conductor of each phase is concentrically installed within its own enclosure, supported by insulators.
7.4.2
Major components
Main bus From generator terminals to step-up transformer
Tap-off bus from main bus duct to unit auxiliary transformer
Generator neutral grounding bus
Generator neutral grounding devices
7.4.3
Design criteria
7.4.3.1
General Bus type shall be isolated-phase, metal enclosed for indoor and outdoor service. The connections shall be designed to withstand full asymmetrical peak currents under short circuit fault conditions. Neutral connections shall be designed for full phase to earth voltage, and shall be adequately rated to take the full unrestricted fault current for three seconds. The busbar installations shall comply with IEC 60071, IEC 60105, and IEC 60298. Induced currents in adjacent structures shall be kept to a minimum. A means of preventing electrolytic corrosion shall be provided where the conductor is connected to a dissimilar metal. 7-14 KHABAT TPP UNITS 1&2 - VOLUME I
Disconnecting links shall be provided in the connections to transformers. Earthing of the busbars shall comply with IEEE 665. All enclosures for generator neutral connections, generator neutral earthing equipment, generator frame, generator main connections, voltage transformers, excitation transformer, unit transformer and generator transformer shall be connected to a main connections earth bar. This earth bar shall be positioned away from the main connections so as to prevent excessive forces being produced under earth fault conditions. 7.4.3.2
Enclosures Enclosures shall be designed to exclude dust and moisture and be suitable for operating over long periods without maintenance or insulator cleaning. Where connections are installed external to the turbine hall they shall be completely weatherproof. Enclosures shall incorporate means to allow for thermal expansion, and also for any small discrepancies in alignment or location. Flexible connections shall be used to connect the busbars to generators and transformers. Drain plugs shall be provided at the lowest parts of the housings or enclosures. Where the enclosures pass through walls etc, supports and suitable external sealing arrangements shall be provided. Internal seals shall be provided if the walls are fire barriers or external walls. All seals shall be fire resistant with a minimum, one hour rating.
7.4.3.3
Neutral grounding devices A neutral grounding system shall be provided for each generator that shall comprise a distribution transformer with the secondary winding loaded with an appropriately rated loading resistor. The connections to the primary winding of the grounding transformer shall be of adequate cross-section to carry the full unrestricted earth fault current for three seconds. Enclosures shall be provided for the generator neutral connection and grounding equipment. The enclosures shall be provided with anticondensation heaters and internal lighting. The removable rink shall be located in the easily approachable place, and 7-15 KHABAT TPP UNITS 1&2 - VOLUME I
shall be a type it sill be able to separate the generator side when the neutral grounding transformer conservativeness and inspecting. A metal barrier shall be provided between the grounding transformer compartment and the secondary resistor compartment. 7.4.3.4
Pressurizing air system (if required) Compressed air for pressurizing the enclosures shall be taken from the station instrument air system or from a separate compressor system, and be filtered and dried. Whichever method is used 100 per cent redundancy of the air supply, drying and storage system shall be provided. Facilities shall be provided for pressure monitoring and remote and local alarms of high and low bus duct pressure shall be provided. Facilities shall also be provided for blowing out the bus ducts with dry air in order to facilitate rapid cleaning out and drying of the bus duct enclosures after maintenance or a period of shutdown.
7.5
Generator Circuit Breaker
7.5.1
Function The generator circuit breaker will be used as the main power connection and interruption between the generator and the main step-up transformer.
7.5.2
Major Components
Circuit breakers
Disconnecting switches & Grounding switches
Current transformers
2 triads of Voltage transformers with fuses
Surge protection equipment(surge arresters and surge capacitors)
Control cabinet
7.5.3
Design criteria
7.5.3.1
General The breaker shall be natural cooled. It shall be kept cool with maximum temperatures not exceeding the values specified in IEEE C37.013. The circuit breaker shall have separate contact systems for load current carrying and arc interruption. The
circuit
breaker
supporting
insulators,
interrupting
chamber(s),
7-16 KHABAT TPP UNITS 1&2 - VOLUME I
disconnector switch/grounding switch and breaker terminals shall be readily accessible through bolted, gasketed handholes or manholes, or removable panels or doors for maintenance, testing and removal of any parts supplied. The mechanical/electrical strength of all equipment shall be coordinated with the interrupting rating of the circuit breaker. The circuit breaker shall be designed so that it can be installed directly in the isolated phase bus in a horizontal configuration. 7.5.3.2
Generator circuit breaker The circuit breaker shall be SF6 gas self-extinguishing type interrupters. Load current carrying contacts shall be silver-plated copper. Driven mechanism shall be gang-operated, pneumatic or hydraulic, with local position indicator. The mechanism shall be anti-pumping and electrically trip free. A failure in the breaker operating mechanism or a loss of mechanism operating pressure shall not cause contact movement and shall not reduce the breaker's current carrying capability or its dynamic withstand capability when the breaker is in the closed position Two independent trip coils shall be provided. Each coil shall be wired for independent source of control power. Energizing the coils, either separately or simultaneously, shall trip the breaker within the rated time. When loss of SF6 pressure, the circuit breaker must be capable of withstanding indefinitely an out-of-phase voltage across the terminals with the phase angle between the two voltages continuously varying. This requirement is to assure that when the breaker is in the open position it is capable of withstanding voltages to which it can be subjected under such conditions as when the system is out-of-phase with the generator. Each circuit breaker shall be electrically and mechanically trip free type and shall have anti-pump feature. The circuit breaker control system shall include all necessary electrical and/or mechanical interlocks to preclude single or two phase operation of the circuit breaker. The generator circuit breaker design data shall be as the follows :
7-17 KHABAT TPP UNITS 1&2 - VOLUME I
Type :
SF6, indoor
Frequency :
50Hz
Rated voltage :
[15]kV
Rated maximum voltage :
[17.5]kV
Rated current
[8000]A
Rated breaking current (symm) :
:
[63]kA
** [ ] : To be confirmed at detail design stage 7.5.3.3
Disconnect & grounding switch The switch shall be motor-operated with manual override, and capable of operating for design life. The isolating gap of disconnect switch shall be in air of atmospheric pressure and a provision for visual check shall be provided. The switch shall be natural cooled or forced-air cooled with maximum temperatures not exceeding the values specified in IEEE C37.013. A de-coupler is required for manual operation and shall be a manual operating means. The switch shall be gang operated.
7.5.3.4
Main current carrying components and contacts The contacts shall be adjustable to allow for wear and shall be easily replaceable, but should have a minimum of moveable parts. All current carrying components shall be constructed of high-conductivity aluminum or copper with supporting insulators. All nuts and bolts shall be stainless steel with provisions to maintain original contact pressure, even when vibration is present All conductor surface connections to equipment shall be silver plated. Connections to isolated phase bus terminals shall be flexible copper or aluminum, and of the laminated leaf type. Details on the flexible connection shall be supplied by the bus manufacturer. The temperature rise of all current carrying parts shall not exceed the value in IEEE C37.013. 7-18 KHABAT TPP UNITS 1&2 - VOLUME I
7.5.3.5
Instrument transformers All current transformers shall comply with the requirements of IEC 60044-1. Current transformers that are critical for the correct performance of protection devices under severe overload shall also comply with IEC60044-6. All voltage transformers shall comply with the requirements of IEC 60044-2. Capacitive voltage transformers shall comply with the requirements of 60044-5. Primary windings shall be connected to the switchgear through renewable fuses of approved type to IEC 60269 or IEC 60282 and shall be readily accessible. Secondary fuses shall be provided on each voltage transformer located such that they are accessible while the primary winding is live. Secondary windings shall be earthed at one point only through a link in an accessible position. Cubicles shall be provided to accommodate the voltage transformers and associated fuses. Each three-phase set of voltage transformers and fuses shall be separately housed in a phase isolated compartment or cubicle with individual isolating facilities.
7.5.3.6
Surge protection equipment Station type surge arresters shall be mounted on transformer-side of breaker system to provide protection for transformer and generator against overvoltage. Surge capacitors, as listed in the Design Data, shall be mounted on both side of breaker system to provide protection against overvoltage and to support arc extinction in the circuit breaker by TRV limitation.
7.6
Power Transformer
7.6.1
Function The function of the main step-up transformers is to transform the voltage produced by the steam turbine generators [15]kV to 132kV. Unit auxiliary transformers are connected at 15kV to steam turbine generators 1-2 respectively. These unit auxiliary transformers step down the voltage to 6.0kV and serve the power plant auxiliaries through each of 6.0kV switchgear.
7.6.2
Major components
One(1) per unit, main step-up transformers
One(1) per unit, unit auxiliary transformers 7-19 KHABAT TPP UNITS 1&2 - VOLUME I
Four(4), diesel generator unit transformers
Eight(8) per 2units, LV transformers
** Quantity of LV transformer is to be confirmed at detail design stage. 7.6.3
Design criteria
7.6.3.1
Equipment performance and sizing
A.
General Transformers shall comply, and be rated in accordance with IEC 60076 or IEC 60726 where appropriate. Transformers shall be designed to meet the noise requirements of NEMA Standard TR-1. Protection of oil type transformer shall be equipped with accessories such as sudden pressure relay, buchholz relay, pressure relief device, oil/winding temperature detector, instrument transformers, etc. On line condition monitoring equipment shall be fitted to transformer with ratings greater than 20MVA. All winding below 72.5kV shall be fully insulated. Terminal arrangements for wiring shall not restrict access for maintenance. Main step-up transformer and unit auxiliary transformer shall be equipped with on load tap changer on HV side. On load tap changer shall be foreseen to be remotely controlled by ECS in CCR.
B.
Transformer sizing The rated ONAF output of main step-up transformers for steam turbine shall be properly sized to the HV network the total MVA output of the generator and considering output variation depending upon the ambient air temperature, under consideration that all generator-class-B-outputs at nominal lagging power factor. Each unit auxiliary transformer shall be rated to supply the respective unit loads plus other unit loads when other unit auxiliary transformer will be out of service. The transformer has to be provided with flange-connected radiators for ONAN/ONAF operation. Up to 60% of the rated power, the transformer shall operate in ONAN and above ONAF. 7-20 KHABAT TPP UNITS 1&2 - VOLUME I
Diesel generating unit transformers shall be chosen in consequence of diesel generating power. All LV transformers shall be loaded not more than 80% of their rating. All LV transformers of double ended LV switchgear shall be rated to supply the respective unit loads plus other unit loads. C.
Main step-up transformer The main step-up transformer has to be designed as oil-immersed threephase power transformer for outdoor installation. The transformer neutral point on the high voltage winding shall be provided with surge arrester and disconnecting switches. The main step-up transformers design data shall be as the follows:
Type :
3 phase, outdoor
Frequency :
50Hz
Rated voltage :
[138]kV-[15]kV
Type of cooling :
ONAF
Rated output :
190 MVA
Winding connection :
YNd1
Short circuit impedance :
[13]% @190MVA
On load tap changer regulation :
±10 ×1.25% steps
** [ ] : To be confirmed at detail design stage. The high voltage side of the transformer shall be connected by overhead line to the 132kV switchgear. The low voltage side is to be equipped with connection flanges and connect an isolated-phase generator main connection. D.
Unit auxiliary transformer The unit auxiliary transformer shall be designed as oil-immersed three-phase power transformer for outdoor installation. The unit auxiliary transformer shall be designed as two(2) winding transformer but if not applicable because of short circuit current of MV system, unit auxiliary transformer shall be designed as three(3) winding 7-21 KHABAT TPP UNITS 1&2 - VOLUME I
transformer and secondary and tertiary winding shall be same capacity. The transformer neutral point on the low voltage winding shall be provided with neutral grounding resistor cubicle. The unit auxiliary transformer design data shall be as the follows:
Type :
3 phase, outdoor
Frequency :
50Hz
Rated voltage :
[15]kV-6.0kV
Type of cooling :
ONAN/ONAF
Rated output :
[17/26]MVA
Winding connection :
Dyn11
Short circuit impedance :
[7]% @17MVA
On load tap changer regulation :
±10 ×1.25% steps
** [ ] : To be confirmed at detail design stage. The high voltage side shall be equipped with connection flanges and a connection frame to connect an isolated-phase generator main connection. The low voltage side a metal-clad auxiliary bus bar system is to be provided to which the feed-in cables for the 6.0kV switchgear shall be connected. E.
MV/LV transformers The MV/LV transformers have to be designed as dry type three-phase power transformer for indoor installation. The capacity of MV/LV transformers shall be one type under condition of AN. Dry type transformers shall have Class 155(F) insulation, but the relevant temperature rises and total temperatures shall not exceed the limits for Class 130(B) under all site and operational conditions. The transformer neutral point on the low voltage winding shall be solidly grounded. The MV/LV transformers design data shall be as the follows:
Type :
3 phase, indoor
Frequency :
50Hz
7-22 KHABAT TPP UNITS 1&2 - VOLUME I
Rated voltage :
6.0kV-0.4kV
Type of cooling :
AN
Rated output :
[2000]kVA
Winding connection :
Dyn1
Short circuit impedance :
[8]% @2000kVA
No load tap changer regulation :
±2 ×2.5% steps
** [ ] : To be confirmed at detail design stage. The high / low voltage side shall be equipped for cable connection. F.
Diesel generating unit transformers Diesel generating unit transformers shall have the same features foreseen for the above auxiliary transformers. Their size shall be chosen in consequence of diesel generating power. The main features of diesel generating unit transformers shall be the follows:
Type :
3 phase, outdoor or indoor
Frequency :
50Hz
Rated voltage :
6.0kV-0.4kV or 6.0kV-6.0kV
Type of cooling :
ONAN or AN
Rated output :
[1250]kVA
Winding connection :
YNd1
Short circuit impedance :
[6]% @1250kVA
No load tap changer regulation :
±2 ×2.5% steps
** [ ] : To be confirmed at detail design stage. The high / low voltage side shall be equipped for cable connection. 7.6.3.2
Controls Each of the transformers is provided with two stages of cooling fans. These fans are locally controlled from the local control panel mounted at the transformer
7-23 KHABAT TPP UNITS 1&2 - VOLUME I
Main step-up transformers are equipped with on load tap changer in 1.25% steps, ten (10) above and then (8) below the rated voltage to accommodate variations in 132kV bus voltage. The secondary voltage of the transformers shall be controlled either manually or automatically by Electrical Control System (ECS) in the central control building normally. A local alarm panel at the transformer annunciates the faults on the transformer locally and they are transmitted to the Electrical Control System (ECS) in the central control building. The mechanical protection fault signals for the transformer are transmitted to the transformer protective relay panel (PRP) and the Electrical Control System (ECS). 7.6.3.3 A.
Special feature Core The three-phase transformers shall be core type. The transformer core shall be grounded to the outside of the transformer tank using bushing. To facilitate testing of core clamp insulation, the core ground shall be accessible from a manhole. The ground strap shall be slotted for disconnection without complete removal of hardware and without lowering the oil level. All clamping structures shall have adequate mechanical strength and shall be so constructed as to minimize eddy currents. The core laminations shall have an insulating coating, resistant to the actions of hot oil. The core shall be carefully assembly and rigidly clamped to ensure adequate mechanical strength and minimum vibration under all operating conditions. The core and coils shall be so fixed in the tank that shifting will not occur when the transformer is being moved.
B.
Coils The windings shall be made of copper conductor and of surge proof design to provide best protection against impulse stress. Coils, winding insulation and leads shall be braced and shaped to withstand the expansion and contraction due to temperature changes, and also to avoid the distortion and abrasion due to any abnormal operating conditions 7-24 KHABAT TPP UNITS 1&2 - VOLUME I
such as short-circuit, etc. The winding shall also be designed to permit the free circulation of insulating oil and to reduce the local overheating. All lead wire from winding to terminal board & bushing shall be securely held by appropriate means to prevent being damaged from the shifting or vibration of the winding and joints. Coil and core assembly shall be vacuum dried at the factory. C.
Tank The transformer shall be enclosed in a suitably stiffened welded steel tank such that the transformer can be lifted and transported without permanent deformation or oil leakage. Lifting lug shall be provided, suitable for the weight of the transformer, including core and windings, fittings, and with the tank filled with oil. The base of tank shall be so designed that it is possible to move the complete transformer unit in any direction without injury when using rollers, plates, or rails.
D.
Cooling system The cooling equipment shall consist of necessary coolers, fans and pumps in such combination as required, complete with automatic control equipment required to maintain the specified temperature rise. The cooler fans shall be readily replaceable and shall be individually thermally protected with thermoguards. All fans shall have safety guards. Circuit breakers for motors shall have the magnetic trip elements in all three phases. The Bidder shall have ambient compensated thermal overload elements in all three phases of motor circuits. Heat exchangers shall be the removable bolted flange type. There shall be shutoff valves at the top and bottom connection of the tank. Cooler mountings shall be such that transformer vibration will not cause excessive wear to the fan motor and pump motor bearings. Heat exchangers shall be arranged to provide access for cleaning and painting without removal. In those cases where the cooler cannot be hung from the transformers due to its weight, steel supports shall be furnished to facilitate mounting including all required mounting bolts, nuts, washers, etc.
7-25 KHABAT TPP UNITS 1&2 - VOLUME I
E.
Oil preservation system Adequate oil preservation system shall be considered for protecting the insulating oil from atmospheric moisture contamination in accordance with the capacity and the voltage class of transformer.
F.
Bushings Bushings shall have electrical and mechanical characteristics suitable for the service voltages specified and shall comply with IEEE C57.19.00 and IEEE C57.19.01. Insulation power factor shall not exceed the values specified in IEEE C57.19.01. Power factor test values shall be supplied for all bushings.
G.
Control and protection equipment The wiring of all the devices installed on board of the transformer shall be terminated to a terminal block inside a control cubicle that will be fitted. The control cubicle houses power receptacles, terminal blocks, push buttons, isolating switches, contactors, thermal relays and circuit breakers for motor protection, indicating lamps, etc., and shall be provided with hinged lockable door. The transformer shall be equipped with an undervoltage time delay relay with a normally open alarm contact to close on low voltage in the fan motor and pump motor AC power supply. All auxiliary relays, devices, and controls required for operation of the cooling system shall be furnished. Contacts shall be provided to operate remote on and off signal lights for each cooler set.
7.7
Switchgear
7.7.1
Function Incoming breakers from the unit auxiliary transformer and the tie breaker for the other bus shall be suitable for an automatic fast bus transfer scheme where the closing of the tie breaker shall be initiated by the normally closed contact of the unit auxiliary transformer breaker. And the slow transfer scheme shall be provided to back-up the fast transfer mentioned above after decay of bus residual voltage. To prevent exceeding the interrupting capacity of the breakers, their operating characteristics shall preclude paralleling of both incoming circuits during fast and slow automatic transfers. Momentary parallel operation of those two breakers may be required during manual 7-26 KHABAT TPP UNITS 1&2 - VOLUME I
transfer. The transfer scheme of shall be complete with all interlocks, check synchronism relays, and voltage measuring equipment necessary for complete implementation of the scheme. The transfer scheme shall have the facility to continuously monitor the status of all associated circuit breakers. It shall also provide a continuous comparison of all voltages of the busbars, and incoming circuits so that if the two circuits are synchronous when the system is activated a fast transfer will take place. Four diesel generators shall be provided. A black start shall require no more than three diesel generators to be in operation. The diesel generators shall be connected to a dedicated switchboard, which in turn shall be connected to each of the unit boards. The switching arrangements shall be such that only one of the unit boards can be supplied by the diesel generators on startup. The load shall only be transferred to the unit auxiliary transformer after the respective generator has been connected to the transmission system and is providing load above minimum stable generation. The transfer of load to the unit auxiliary transformer shall take place by synchronizing across the unit board incomer. This synchronizing facility shall only be in service when the diesel generators are supplying load. Once load has been transferred to the unit board the respective diesel generator circuit breakers shall open, and the diesel generators shall begin their shut-down sequence. Upon loss of supply one diesel generator shall start, and load shall be transferred to the diesel generator upon attaining full speed. Once the essential loads have been safely shut-down the respective diesel generator circuit breaker shall open, and the diesel generator shall begin its shutdown sequence. If a black start is requested during the shut-down sequence, the diesel generator supplying the shut-down load shall remain in service maintaining the essential loads. Up to two additional diesel generators shall start, and shall be synchronized to the diesel generator supplying the shut-down load. The black start sequence shall only commence when all of the diesel generators are synchronized. 7.7.2
Major components
Metal enclosed switchgears
Circuit breaker(VCB, ACB, MCCB) 7-27 KHABAT TPP UNITS 1&2 - VOLUME I
VTs, CTs
Meter, Relay
7.7.3
Design criteria
7.7.3.1
General All auxiliary equipment within the switchgear shall comply with IEC 60947. The overall height of switchboards shall not exceed 2.5 m. All switchgear shall be accessible for maintenance from both front and rear without the need for extensive removal of internal equipment. It shall not be possible to accidentally access live parts of the equipment. Control sections and cable compartments shall be provided with internal lighting. All auxiliary switches in both MV and LV switchboards shall be wired to a fixed terminal board. Each LV switchboard which comprises a bus section, shall be complete with a control circuit transformer on each side of the board. The rating of each control transformer shall be based on the assumption that the bus section is closed and one transformer is out of service. The primary winding, and the non earthed pole of the secondary winding shall be connected through a fuse. Internal wiring shall be run in low smoke and fume (LSF) trunking. No more than two wires shall be connected to one terminal. Wires shall be identified at each end. Wiring above 50 V, or wiring connected to pilot cables shall be segregated from other wiring. Terminal blocks shall be stud or insertion type. Spare terminals shall be provided. All terminal blocks shall be labelled with a unique identification reference. All indicating instruments shall be in accordance with IEC 60051 Class 1.0. Motor ammeters shall be capable of withstanding motor starting currents. Voltage operated instruments shall be protected by a fuse
7.7.3.2
MV switchgear MV switchgear shall be metal clad vacuum and comply with IEC 60056 and 7-28 KHABAT TPP UNITS 1&2 - VOLUME I
IEC 60298. The switchgear shall be dead front type. The feeders of MV switchgear except for motor feeders shall normally be controlled from ECS. The incoming connections to boards shall be MV cables. Circuit breaker status shall be visible from the front of each circuit breaker cubicle. Circuit breakers shall be fully withdrawable for maintenance and isolation purposes. VTs shall be supplied through fuses on the primary side. It shall be possible to remove the fuses without dismantling the equipment. Each compartment shall be padlockable. Earthing facilities shall be provided for each circuit and the switchboard busbar. Earthing of the switchboard busbars shall be electrically interlocked. The short time rating shall be 40kA. If not applicable, unit aux, transformer may be 3 winding type and 6.0kV switchgear buses may be divided. The switchgear shall be extensible at both ends. Each feeder panel shall contain separate compartments with earthed metal enclosures for each of the following compartments:
Circuit breaker compartment
Low voltage compartment
Cable connection compartment
Busbar and circuit shutters shall be individually operated and able to be independently padlocked closed. Suitable handling equipment shall be provided for circuit breakers. Mechanical or electrical safety interlocks shall be provided for isolation and maintenance and to avoid unsafe switching conditions. A steel cabinet shall be provided with all necessary tools and maintenance equipment. A separate cabinet shall be supplied with keys and padlocks necessary for safety and control management. Each room in which MV switchgear is installed shall be provided with an insulated hook. The 6kV unit switchgear main feature shall be the followings: 7-29 KHABAT TPP UNITS 1&2 - VOLUME I
7.7.3.3
Nominal voltage :
6 kV
Rated maximum voltage :
7.2 kV
Lighting impulse voltage :
60 kV
Power frequency withstand voltage :
20 kV
Rated current : [3150] A ** The rated current of diesel generator switchgear can be reduced to 1250A
Rated short circuit current(3sec) :
40 kA
Rated peak withstand current
104 kA
:
LV switchgear LV switchgear shall be free standing, and Form 4b in compliance with IEC 60439-1. The feeders of MV switchgear except for motor feeders shall normally be controlled from the ECS. Where the incoming supply is from a transformer with a rating in excess of 1250kVA, the terminals shall be arranged for the connection of phase segregated busbars. Circuit breakers shall be the stored energy draw-out type, three-pole, single throw, electrically and mechanically trip-free, and shall be provided with a mechanical interlock to prevent the breaker from being inserted into or withdrawn from the operating position when the circuit breaker is closed The short time rating shall be in accordance with the results of fault studies. Busbars shall be copper, and shall comply with IEC 60439-2. Busbar insulation shall be in accordance with the relevant phase color. Suitable handling equipment shall be provided for circuit breakers or starters. Mechanical or electrical safety interlocks shall be provided for isolation and maintenance and to avoid unsafe switching conditions. The LV common site boards shall be equipped with two incomers and a bus tie section. These three circuit breakers shall be interlocked to ensure that only two out of three can be closed at any one time. The 400V switchgear main feature shall be the followings: 7-30 KHABAT TPP UNITS 1&2 - VOLUME I
7.7.3.4
Nominal voltage :
400 V
Rated maximum voltage :
1 kV
Power frequency withstand voltage :
3 kV
Rated current
3150 A
Rated short circuit current(3sec) :
:
40 kA
LV boards(MCC) LV boards shall consist of vertical sections, jointed together to form a rigid, completely enclosed control assembly. All required auxiliary relays, for and individual starter, shall be contained within the starter unit. All motor starters and feeder cubicles shall be fully withdrawable. All the low voltage boards shall be metal clad type and in compliance with IEC 60439. The LV board that feed also emergency loads shall be designed as follow: the incoming feeder shall supply emergency bar, that is connected to the bar of non essential load through a circuit breaker. During emergency events, the above mentioned circuit breaker shall kept open. Where the incoming supply is from a transformer with a rating in excess of 1250kVA, the terminals shall be arranged for the connection of phase segregated busbars. Molded case circuit breakers for motor feeders shall be single throw, magnetic only type with adjustable instantaneous trip elements and trip-free mechanism. Molded Case Circuit breakers for non-motor feeders shall be single throw, with inverse time, thermal and magnetic element overload protection and trip-free mechanism. Circuit breakers shall be equipped with an external operating mechanism to allow operation from the front with the unit door closed. The operating mechanism shall clearly indicate whether breaker is ON, OFF, TRIPPED. The opening on the door shall be provided with a gasket. The control units shall be readily removable, with access to all components and wiring from the front. Units of the same size and type shall be interchangeable where control and power circuitry permit. The control units shall be provided with, but not limited to, miscellaneous components such as indicating lights, pushbuttons, relays, instrument transformers, and other devices.
7-31 KHABAT TPP UNITS 1&2 - VOLUME I
Starter units shall be of the combination type, using molded-case circuit breakers and magnetic contactors. Contactors shall be capable of withstanding the motor stalled current until the associated protection device operates. Contactors shall comply with IEC 60439-4. Contactors shall be capable of closing when a minimum transient voltage of 80% of the nominal voltage is applied to the primary of the control transformers. The short time rating shall be in accordance with the results of fault studies. Busbars shall be copper, and shall comply with IEC 60439-2. Busbar insulation shall be in accordance with the relevant phase color. Composite fuse and switch equipment in the form of either a fuse-switch or switchfuse shall comply with IEC 60439-3. Mechanical or electrical safety interlocks shall be provided for isolation and maintenance and to avoid unsafe switching conditions. The 400V board main feature shall be the followings:
Rated voltage :
400 V
Rated maximum voltage :
1 kV
Power frequency withstand voltage :
3 kV
Rated current
[800] A
Rated short circuit current(3sec) :
:
7.8
DC Supply System
7.8.1
Function
[40] kA
Separate DC systems shall be provided for each unit and also for the station. Each system shall have a fully rated battery and two 100 percent rated chargers. The batteries shall normally be connected to the load in parallel with the chargers, and shall supply the loads when ac supplies to the chargers are not available. Two 220 VDC systems should be installed to feed emergency oil pumps, controls, protections and auxiliary services of the power plant, including the switchyard. 7.8.2
Major components 7-32 KHABAT TPP UNITS 1&2 - VOLUME I
DC Switchgear
Battery charger
Batteries
7.8.3
Design criteria
7.8.3.1
General Indicating lamps shall be provided on the equipment to indicate battery and charger faults, the faults shall also be remotely indicated to the plant control system. The cable connections between battery chargers and/or batteries and/or busbars are to be carried out with single-conductor cables. The individual cubicles are to be bulk-headed against one another by sheet metal walls or equivalent material.
7.8.3.2
DC switchgear The main switchgears are to be provided as indoor, steel-enclosed cubicles and are to be furnished with fix mounted equipment and single busbar systems. Main switchgears for 220 VDC shall comprise one (1) busbar section. The infeed from the battery is to be taken via MCCB. All outgoing feeders from the main switchgear to consumers are to be equipped with monitored fuses and hand-operated load-break switches or with MCBs with auxiliary contacts. The 220 VDC systems shall each be equipped with an earth fault and insulation monitoring device in addition to the Voltmeter and Ammeter. Each unit shall be equipped with individual signal lamps and position indications that show the following switching conditions locally:
switch unit ON/OFF
unit not available (not engaged/test)
unit OFF - due to fault.
The following signals shall be additionally provided in the infeed panels of the switchgear: 7-33 KHABAT TPP UNITS 1&2 - VOLUME I
7.8.3.3
no control voltage
no busbar voltage
ground fault
Battery charger Battery chargers shall have natural cooling. If air-cooling is required, then 100% air fans with monitoring and alarm signal shall be provided. It shall be possible to carry out maintenance on one charger with the other in service. Each charger shall be capable of recharging the battery within eight hours after a complete discharge. Boost charging of each battery system shall be carried out off-line. It shall be possible to operate the charger without the battery. Under this condition the dc voltage ripple shall not exceed 10% peak-to-peak of the battery float voltage under loading conditions over the range 0 to 100% rated output. The chargers shall be designed such that heat losses do not give rise to excessive temperatures within the charger or the surface of the cubicle. The cubicle surface temperature shall not exceed 65℃. The battery chargers are to be arranged in sheet steel cubicles, which are to be matched to the switchgear cubicles in respect of height and other dimensions. Each battery charger shall be suitable for the charging and floating of the Lead Acid and for supplying the DC consumers and inverter for the UPS system at the same time. Above requirements shall also be applicable if the battery was drained prior to start of charging. The battery chargers are to be provided as thyristor controlled devices with current-voltage characteristic for stand-by parallel operation with the associated batteries. The following technical features and monitoring equipment is to be provided for the individual battery chargers :
monitoring the charging circuit for interruption
voltage monitoring of the incoming three-phase supply, with an overvoltage of +15% and an undervoltage of -15%
7-34 KHABAT TPP UNITS 1&2 - VOLUME I
voltage monitoring of the DC output, with an overvoltage of +15%
All cases of disconnection shall be indicated as a fault alarm in the front door of the unit. The local fault alarms and disconnections are to be combined as a common alarm - battery charger fault - to the central control room. The necessary monitoring equipment, measuring instruments, other devices, switches, indicator lamps, etc. shall be provided on the front of the rectifier cubicles. Alternatively, an integrated numeric control device (visible during normal operation through inspection window in front door) shall be substituted. 7.8.3.4
Batteries Their sizing shall be done as per IEEE 485 and it shall allow autonomy of at least two hours after the safe shutdown of all the power plant. Each battery shall be complete with stands, all intercell connections, and connections between the battery terminals and the switchgear. Batteries shall be of the lead-acid type or Ni-cads and shall be suitable to operate satisfactorily under all conditions prevailing at site. The fuse supervisory contact shall give an alarm to the control room. The rating of the batteries shall be determined to suit the full load requirements of the plant being provided (proved by calculation). At the end of the rated discharge period the voltage available at the terminals of the equipment being controlled shall not be less than the minimum operating voltage of the equipment being supplied. However, at the end of the rated discharge the minimum voltage per cell shall not be less than under voltage of -15%. The rated capacity shall be adequate for minimum discharge duration.
7.9
Uninterruptible Power Supply System
7.9.1
Function An Uninterruptible Power Supply 230Vac system shall be foreseen to supply power to the control, computer and communication system. The Uninterruptible Power Supply shall be totally redundant and it shall have 7-35 KHABAT TPP UNITS 1&2 - VOLUME I
autonomy of two(2) hours. 7.9.2
Major components
AC switchgear
Inverter with electronic change-over equipment
7.9.3
Design criteria
7.9.3.1
General The UPS equipment shall comply with IEC 60146-4. The UPS equipment shall have isolation facilities to permit full replacement without disrupting any part of the system to which it is normally connected. The equipment shall be complete with local alarms and a common alarm shall be repeated to the plant control system. For maintenance purposes an independent manual by-pass switch shall be provided to allow the loads to be fed from an alternative source. The individual cubicles are to be bulk-headed against one another by sheet metal walls or equivalent material.
7.9.3.2
AC switchboard The AC switchboards are to be provided as indoor, steel-enclosed cubicles and are to be furnished with fix mounted equipment and single busbar systems. All outgoing feeders from the AC switchboard to consumers are to be equipped with monitored fuses and hand-operated load-break switches or with MCBs with auxiliary contacts. A set of voltmeter, Ammeter and Frequency meter shall be provided for each busbar. Each unit shall be equipped with individual signal lamps and position indications that show the following switching conditions locally:
switch unit ON/OFF
unit not available (not engaged/test)
unit OFF - due to fault.
7-36 KHABAT TPP UNITS 1&2 - VOLUME I
The following signals shall be additionally provided in the infeed panels of the switchgear:
7.9.3.3
no busbar voltage
Inverter with electronic change-over equipment The inverters are to be arranged in sheet steel cubicles, which are to be matched to the switchgear cubicles in respect of height and other dimensions. The inverters shall be designed for operation with natural cooling. If aircooling is required, then 100% air fans with monitoring and alarm signal shall be provided. In order to be able to maintain an emergency supply in the event of grid and generating failure, an inverter with automatic electronic change-over equipment and manual bypass switch/facility is to be provided. The static inverter shall be suitable for 100% of the power requirement at the corresponding fed AC switchboard. The following features and monitoring equipment is to be provided for the AC inverter:
Radio interference suppression according to the appropriate IEC publications
DC undervoltage monitoring
AC overvoltage monitoring
AC undervoltage monitoring.
On activation of the above devices, switch-over to power supply from the AC bus shall occur. The fault is to be individually indicated locally. The fault alarms are to be combined as a common alarm - inverter fault - to the central control room. The inverter is to be protected on the input and output sides and is to be equipped with the necessary isolating points. It shall be possible to block the inverter on the input side in the case of high rate battery charging or they shall be so designed that no damage will occur during this phase of charging. All the necessary control switches, measuring instruments etc. are to be 7-37 KHABAT TPP UNITS 1&2 - VOLUME I
installed in the front of the cubicles. Alternatively, an integrated numeric control device (visible during normal operation through inspection window in front door) shall be substituted, which combines all functions. Sizing of fuses and inverter output in case of short circuits shall be properly coordinated and shall be fully selective under all operating conditions. An electronic change-over device is to be provided and shall enable automatic, uninterrupted, synchronous switch-over to the consumer busbar in the event of total inverter failure or high voltage dip on the safe busbar. 7.10
Electrical Control System
7.10.1
Function The Electrical Control System (ECS) shall be installed in the Central Control Room(CCR) to control and monitoring the plant electrical system and its operating status. Normal control position of the plant electrical power system shall be the Electrical Control Panel. The Electrical Control System (ECS) shall cover control and monitoring of 150kV AIS system.
7.10.2
Major components
7.10.2.1 HMI & communication
Dual operator workstations
Engineering workstation
Color printer and event printer
Large scale display unit
Communication equipment, fiber optic cable, GPS and accessories
Metering system
7.10.2.2 Bay control panel
132kV switchyard bay control panel
Low voltage system bay control panel
7.10.2.3 Protective relay
Generator protective relay
Unit overall differential protective relay
Main step-up transformer protective relay
7-38 KHABAT TPP UNITS 1&2 - VOLUME I
7.10.3
Unit auxiliary transformer protective relay
6.0kV medium voltage protective relay
Diesel generator protective relay
132kV switchyard bus protective relay with breaker failure function
132kV T/L protective relay
Design criteria
7.10.3.1 General The relays and controllers shall be based a microprocessor that operates asynchronously and can communicate data and/or commands over a communications network (e.g. protective relay, controller, and microprocessor based meter). Operator can control and supervise electrical equipment via protective relays, and controller. The relays and controllers must have measuring functions based on this specification and measuring accuracy shall be at least 1%. Also, relays and controllers shall have event record function, and resolution time shall be 1ms(including time synchronizing error). All relays performing a measuring function shall be of numerical design with continuous self-monitoring. Numerical relays and schemes provided shall:
Be suitable for connection to a local communications network
Be provided with an integral local user interface
Offer instrumentation, disturbance recording and event logging functions in addition to providing protection.
Architecture of system shall be able to operate independently of each other. Refer to Vol. III “Configuration drawing”. 7.10.3.2 Human-Machine Interface (HMI) LCD monitor of OWS and EWS shall be at least 21 inches with pixel resolution 1280 x 1024. Two(2) sets large scale display unit shall be at least 50 inches with resolution 1280 x 1024 pixels of DLP or LCD type. 7.10.3.3 Communications network requirements 7-39 KHABAT TPP UNITS 1&2 - VOLUME I
Communication network shall connect the redundant operator workstation with the engineering workstation. Communication network protocol between workstations shall be TCP/IP. The communication network shall connect all IEDs and the station level equipment. The communication network shall be open. It shall comply with the prevalent international standards (IEC 61850, etc.). Communication network shall direct connect all IEDs and the station level equipment with fiber optic cable. It shall be TCP/IP 100Mbps or higher. 7.10.3.4 Construction The electrical control panel shall be freestanding structures. The panels shall be welded construction of hot rolled steel plate. 7.10.3.5 Items for remote control and supervision The electrical control and supervision shall be of such an extent as to suit the specified purpose and the requirements. The control and supervisory indication points listed below are minimum requirement, and further points and details shall be developed by the Bidder subject to the KNOC’s approval. A.
B.
C.
D.
150 kV AIS ;
Bus : Volt
Feeder : Volt, Ampere, Watt, Var
Circuit breaker, disconnectors and earthing switches status indications
Circuit breaker and disconnectors On/Off control switches
Main step up transformer
Temperature indications (Oil, HV winding, LV winding)
Watt, Watt-hour, Var
On load tap changer positions and controls
Unit auxiliary transformer
Temperature indications (Oil, HV winding, LV winding)
Watt, Watt-hour, Var
On load tap changer positions and controls
Generators 7-40 KHABAT TPP UNITS 1&2 - VOLUME I
E.
F.
G.
H.
Volt, Ampere, Watt, Var, Hz, Power factor
6.0 kV switchgears, each ;
Incoming feeder : Volt, Ampere, Watt, Synchronizing function
Bus Volt
Tie feeder : Volt, Ampere, Synchronizing function
Outgoing feeder : Ampere, Watt
Circuit breaker status indications (On/Off)
Circuit breaker control (On/Off), except motor feeders
400V switchgear, each ;
Incoming feeder : Volt, Ampere, Watt, Synchronizing function (double ended bus only)
Bus Volt
Tie feeder : Volt, Ampere, Synchronizing function
Incoming feeder and Tie feeder circuit breaker indication and control (On/Off),
DC 220 V system
Charger incoming Ampere
Charger output : Volt, Ampere
Distribution board bus Volt
Batteries incoming Ampere (bidirectional)
Circuit breaker status (On/Off) - charger incoming, battery incoming, dist. board incoming and outgoing to Vital AC 230 V system
Vital AC 230 V system
UPS incoming Ampere
UPS output : Volt, Ampere
Distribution board : Volt, Ampere, Hz
Circuit breaker status (On/Off) – incoming from DC 220 V dist board, incoming for by-pass regulator transformer, incoming for rectifier, outgoings from inverter and regulator transformer, dist. board incoming and switch status (static switch isolator, manual by-pass changeover switch)
7-41 KHABAT TPP UNITS 1&2 - VOLUME I
I.
Emergency diesel generator
Volt, Ampere, Hz , Power factor
Circuit breaker status indication and control with synchronizing function
DG Manual/Auto start mode
DG Voltage Raiser/Lower mode
Necessary analog signal such as MW of generator and transformer and SOE signal such as breakers status shall be provided the PCS. 7.11
Electrical Protection
7.11.1
General The protection system shall be designed to provide an overlapping protection of the complete electrical equipment. Protection relays shall be type tested in accordance with the relevant sections of IEC 60255. Each protection relay shall have means by which the user can apply the settings, and a unique identifier that is clearly visible. All back up protection systems shall be able to discriminate with main protection systems, circuit breaker fail protection (if fitted) and other back up protection systems installed elsewhere on the system. Adequate facilities shall be provided within the protection scheme to enable the protection equipment to be tested from the front of the protection equipment panel with the primary circuits in service with test points clearly labeled. An overall differential covering the generator, main connections, and generator transformer shall be included for each unit. The protection system shall operate satisfactorily when tested to IEC 600682, IEC 60255-21, and IEC 60255-22. Lock-out relays shall be provided for generator and transformer protection. Lock-out relays shall be manual reset type.
7.11.2
Design criteria
7.11.2.1 132kV AIS protection For protection specification of 132kV air insulated switchgear, refer to Part 4 Volume 1 Section 9. 7-42 KHABAT TPP UNITS 1&2 - VOLUME I
7.11.2.2 Generator protection Two separate and completely redundant generator protective relays shall comprise, but not be limited to, the following functions:
Back-up distance (21)
Reverse power stage 1+2 (32)
Loss of excitation stage 1+2 (40)
Negative sequence (46)
95% stator ground fault (59N-1)
100% stator ground fault (59N-2)
Volts per hertz over excitation stage 1+2 (59/81)
Voltage balance (60)
Under/over frequency stage 1+2+3+4 (81)
Generator differential (87)
Generator circuit breaker failure (50BF)
Out-of-step protection (78)
7.11.2.3 Unit overall differential protective relays shall provide, but not be limited to, the following functions.
Unit Overall Differential (87U)
7.11.2.4 Main step-up transformer protection Main transformer protective relays shall provide, but not be limited to, the following functions
Transformer differential (87T)
HV Restricted earth fault (87TG)
Neutral overcurrent (51N)
As a minimum, the following supplementary generator transformer main tank protection devices shall also be provided:
Sudden pressure relay
Buchholz relay
Pressure relief device 7-43 KHABAT TPP UNITS 1&2 - VOLUME I
Winding/Oil over-temperature
Oil level
7.11.2.5 Unit auxiliary transformer protection Unit aux. transformer protective relays shall provide, but not be limited to, the following functions:
Neutral overcurrent (51N)
Back-up overcurrent (50/51)
Transformer differential (87T)
Unit aux. transformers shall also be provided with the following supplementary protection devices:
Sudden pressure relay
Buchholz relay
Pressure relief device
Winding/Oil over-temperature
Oil level
7.11.2.6 LV transformer protection All dry type transformers shall be provided with winding temperature protection. 7.11.2.7 Black start diesel generator protection Each diesel generator shall be provided with protection equipment that shall protect the generating plant from damage due to fault conditions. All relays or similar equipment for overspeed, oil pressure, cooling water level and high cooling water temperature, directly associated with the prime mover shall be mounted on the generating set engine and associated with a suitable trip relay. Protection equipment shall be provided and arranged to trip the associated circuit breaker, suppress the excitation and shut down the prime mover if faults should occur. Each generator shall be provided with the following protection functions as a minimum:
Reverse power (32)
Negative sequence (46G) 7-44 KHABAT TPP UNITS 1&2 - VOLUME I
Voltage controlled overcurrent (51V)
Undervoltage (27G)
Volts per hertz over-excitation (59/81)
Generator differential (87)
Ground overvoltage fault (59G)
Under frequency (81-1)
Over frequency (81-0)
Frequency transmission function (81-2)
7.11.2.8 Medium voltage switchgear A. Incomer and Bus Tie
B.
Phase overcurrent, time inverse (51)
Residual overcurrent, time inverse (51N)
Undervoltage (27)
Phase sequence (47)
Synchronism check (25)
Feeder
Phase overcurrent, instantaneous (50)
Phase overcurrent, time inverse (51)
Ground fault overcurrent, instantaneous (50G)
7.11.2.9 Low voltage switchgear A.
B.
C.
Incomer and bus
Trip Device integrated in overcurrent (50/51)
Ground fault overcurrent, time inverse (51N)
Undervoltage (27)
MCC feeder
SST Trip Device integrated in overcurrent (50/51)
Ground fault overcurrent, time inverse (51G)
Motor and non-motor feeder 7-45 KHABAT TPP UNITS 1&2 - VOLUME I
7.12
SST Trip Device integrated in overcurrent (50/51)
Ground fault overcurrent instantaneous (50G))
Synchronizing Each generating set shall be provided with an automatic/manual synchronizing scheme via LCD monitor from the turbine control system, synchronizing each of the generators across the respective generator circuit breaker. Each diesel generators shall be provided with an automatic and manual synchronizing scheme. The synchronizing equipment for the unit board incomers shall be situated alongside that of the diesel generator synchronizing equipment. The synchronizing scheme shall also allow the diesel generators to be exercised on load for test purposes. In addition each scheme shall be provided with a check synchronizing relay and selector switch for manual, auto, test and off. The test position shall be a simulation of the circuit breaker closing.
7.13
Motors
7.13.1
General Motors shall comply with the requirements of IEC 60034 and IEC 60072. MV motors shall be rated 6,000 volts, 3 phase, 50Hz. (larger than 200kW) LV motors (including 1/2HP and MOV) shall be rated 400 volts, 3 phase, 50Hz. Motors rated 75kW and above shall be low voltage and connected to the LV switchgear. Motor rated below 75kW may be connected to the LV boards(MCC). Fractional horsepower motors rated below 1/2HP shall be rated 230 volts, single phase, 50Hz. DC motors shall be rated 220 volts. DC motors shall be suitable for reduced voltage starting limiting starting current to 200 percent. All LV motors shall be of high efficiency type.
7.13.2
Design criteria All motors rated 100kW and above shall be fitted with winding temperature detectors.
7-46 KHABAT TPP UNITS 1&2 - VOLUME I
All motors shall be designed for direct on line starting and capable of starting the driven load at 80% rated voltage. Motors shall be of the totally enclosed fan cooled type (TEFC) with the exception of large MV motors which may be of the closed circuit air cooled (CACA) or closed circuit water cooled type (CACW). Motor enclosures shall be IP54 for indoor applications and IP55 for outdoor applications. Winding insulation shall be to Class 155 (F) with temperature rises and total temperatures restricted to Class 130 (B) limits. All MV and outdoor motors shall be fitted with anti-condensation heaters. Rolling element type bearings shall comply with ISO standards. Oil lubricated bearings shall be fitted with an accessible drain plug, and means of observing the oil flow. The thrust bearing on vertical type motors shall be coordinated with that of the pump. Where necessary, provision shall be made to prevent damage to bearings caused by shaft currents. Terminal boxes shall be totally enclosed to prevent the ingress of dust and moisture. The supply cable shall have a separate terminal box. The arrangement of terminals and cable connections shall permit the motor to be disconnected from the supply cable without damaging the sealing, glanding or connections. MV motors shall have phase segregated terminals and the terminal box and fittings shall not fail in a manner hazardous to personnel in the event of an internal fault. LV motors shall have insulating barriers between terminals. Motor air coolers shall be of adequate capacity to dissipate the motor losses, and should include for expected fouling that can occur between overhauls. Materials for air coolers shall be selected to provide resistance to corrosion. 7.14
Earthing and Lightning Protection
7.14.1
Function 7-47 KHABAT TPP UNITS 1&2 - VOLUME I
An earthing system shall assure:
7.14.2
The personnel safety;
Limitation of contact and step voltages;
Static electricity protection;
Lightning discharge protection;
Service earthing.
Design criteria
7.14.2.1 Earthing A site survey shall be undertaken to determine the soil resistivity. Based on these results a study shall be carried out to determine the touch and step potentials of the new system. The design and installation shall comply with IEEE 80, IEEE 665, IEEE 1050, BS 6739 and BS 7430. The maximum resistance of the grid shall be one ohm (1 Ω). The earthing of instrumentation and electronic circuits shall be done according to their manufacturer requirements and IEEE 1050. Connections to substation earthing systems shall be made by disconnecting links readily accessible for test purposes. All disconnecting links and distribution bars shall be supported from insulators. Earthing distribution bars shall be strategically positioned around the plant areas. All metallic casings, frames and tanks of electrical equipment shall be bonded to the earthing system, along with all structural steelwork, metallic fences and gates, and steel reinforcing. Connections to electrical equipment shall be detachable from the earthing bolt or stud. Cable trays and ladder racking shall be earthed at regular intervals. Generator neutrals shall be connected through a resistor in order to limit the fault current to 10 A. Star connected primary windings of the generator and station transformers shall be solidly earthed. Star connected secondary windings of station and 7-48 KHABAT TPP UNITS 1&2 - VOLUME I
unit transformers shall be either solidly earthed or earthed through a resistor. Switchboard earth bars shall be connected to the earthing system at each end of the equipment. Dedicated earth bars and disconnecting links for electronic equipment shall be clearly identified. Pipelines entering the site shall be fitted with an insulated flange at the boundary. The minimum resistance across the flange shall be one thousand ohms (1 kΩ). Conductors shall be stranded high conductivity copper to IEC 60228. Where ground rods are used they shall be hard drawn high conductivity copper with hardened steel driving caps and tips. All underground or embedded grounding connections shall make use of compression type connectors or Induction or Cad welding. All major equipment and tanks shall be connected to the main ground grid in two places of opposite sides. All metallic structures and equipment, such as motor frames, switchgear, unit substations, motor control centers, panelboards, lighting cabinets, conduits, cable trays, crane rails, stairs, handrails and railroad spur tracks shall be permanently and effectively grounded. 7.14.2.2 Lightning protection system The power plant shall be protected as per IEEE 665, while HV switchyard as per IEEE 80 and IEEE 998. A properly engineered system shall;
Intercept a lightning stroke before it strikes the structure.
Provide a low-resistance path to ground for the high currents associated with lightning discharges.
Prevent damage to structures and hazards to people.
Have the protective zone of the system in accordance with the latest edition of the lightening protection code (NFPA 780).
7.15
Cabling
7.15.1
General The cable installation shall be complete with all terminations, trays, ladder
7-49 KHABAT TPP UNITS 1&2 - VOLUME I
racks, glands, ferrules, lugs, markers, and fixings. Cables shall be in one continuous length, have high conductivity copper conductors, and comply with IEC 60332-3. Medium and low voltage power cables shall comply with IEC 60502 and IEC 60811. The conductor cross section of each cable shall be adequate for carrying the prospective fault current determined by the next upstream short circuit protection device. The voltage drop between the point of supply and the fixed equipment shall be limited to 3 percent. All power cables shall have phase identification. Galvanized steel wire armor shall be used for multicore cables, aluminum wire armor for single core cables. Single core power cables shall be earthed at one end only. PVC sheathing shall have an oxygen index of not less than 30. Building services wiring shall have XLPE insulation. 7.15.2
Medium voltage cables All medium voltage cables shall be standard single core cables with copper conductor and XLPE or EPR insulated with a LSF sheath. Power cables shall be designed for the thermal and short-circuit characteristics of the electrical systems, taking into consideration a minimum short circuit duration. MV cable shall be supplied in accordance with IEC Standards and rated 6/10 kV.
7.15.3
Low voltage cables All low voltage cables shall be XLPE insulated with a LSF sheath. Low voltage cables shall be in accordance with IEC standards and rated 0.6/1.0 kV. The low voltage power cables shall be standard single and multi-core cables 7-50 KHABAT TPP UNITS 1&2 - VOLUME I
with copper conductor and XLPE insulation. The LV power cables shall be designed for the thermal characteristics of the electrical system and for continuous operation. 7.15.4
Control and instrumentation cables All multicore control cables shall have approximately 20 percent spare cores, but not less than two cores for future use. All cores shall be XLPE or EPR insulated, and numbered throughout their length. All conductors 2.5mm2 and above shall be stranded. Individually screened twisted pairs or overall screened multicore cables shall be provided for control and instrumentation cables.
7.15.5
Optical fiber cables All fiber optic cables shall comply with IEC 60794, and have Aramid type strain relief elements. The cables shall be able to operate continuously in temperatures between –10°C and +60°C. The fiber optic cables shall be loose tube type, with the fibers fed into tubes. The tubes shall be sufficiently strong to hold their shape and provide protection for the fibers against deformation and friction. Each tube shall be color coded. Where fiber optic cables are to be laid in contaminated ground, a water repellent gel filling and a moisture barrier shall be applied longitudinally over the cores to ensure long term water tightness. An inner polyethylene sheath shall contain a hydrogen scavenger to eliminate the risk of hydrogen build up around the fibers during operation. Fiber optic cables which are direct buried shall be armored.
7.15.6
Telephone cables All telephone cables shall have a minimum of two pairs of tinned solid copper conductors. The minimum conductor diameter shall be 0.5mm. All telephone cables shall have color coded core insulation. The insulation and outer sheath of telephone cables for internal use shall be halogen free. Cables with more than six pairs shall have a fire barrier tape. 7-51 KHABAT TPP UNITS 1&2 - VOLUME I
All telephone cables for external use shall have cores embedded in a water repellent gel to prevent the ingress of moisture, and an outer sheath of tough UV resistant polyethylene. Telephone cables that are direct buried shall be armored. 7.15.7
High temperature cables PTFE cables shall be used for applications such as alarms, lighting, and essential services in temperatures up to 260°C. A layer of Mica shall be applied over the PTFE insulation, with an impregnated and varnished glass fiber braid.
7.15.8
Thermocouple and compensating cables Only one color shall be used for the insulation of the negative conductor of both thermocouple extension and thermocouple compensating cables. The insulation of the positive conductor and the outer sheath shall be dependent on the cable type. For intrinsically safe circuits the outer sheath of all extension and compensating cables shall be blue.
7.15.9
Intrinsically safe cables Cables used for intrinsically safe circuits shall have a blue outer sheath in accordance with IEC 60079-14. No other cables shall be supplied with a blue outer sheath.
7.15.10 Mineral insulated cables Mineral insulated (MI) cables shall have copper conductors surrounded by a compressed non hygroscopic mineral insulate with a copper sheath and a halogen free LSF outer sheath. Mineral insulated cables shall only be used where the maximum voltage is ≤ 750V. 7.15.11 Cable installation A. General All cables shall be laid in preformed trenches, direct in ground, in ducts, and supported on racks and trays. Single core cables run in trefoil shall be cleated using non magnetic trefoil cleats which shall be capable of withstanding the forces produced under short circuit conditions. The cleats shall be manufactured from stainless steel.
7-52 KHABAT TPP UNITS 1&2 - VOLUME I
To enable complete redundancy to be maintained, two separate routes shall be used for the data highway. Adequate precautions shall be taken to allow for vibration and expansion as appropriate. The cabling systems of each unit shall be physically separated, or segregated by fire barriers with a minimum of 1 hour fire resistance. Where cables pass horizontally through walls or vertically through floors and ceilings non-combustible, non-metallic fire barriers shall be installed. B.
Cable trays and ladder racks All cable ladders and trays shall be numbered. Cable trays, ladder racks and supports shall generally be heavy duty galvanized mild steel. Stainless steel or GRP shall be used in saline atmospheres. Cables with a diameter of 15 mm or less shall be supported on cable trays. Ladder rack shall be used for cables with a diameter larger than 15 mm. Control cables shall not be run on the same tray or ladder as power cables. Covers shall be provided for trays and ladder rack where the cables are in direct sunlight. Steel cable ties shall be used for vertical runs of cable. PVC and nylon tie wraps shall not be used on horizontal runs that are in direct sunlight. Steel cable ties shall be manufactured from stainless steel. Nylon cable ties shall be flame retardant. Cable ties installed in areas of high temperature shall be manufactured from polyketone. Sufficient cable trays shall be provided to permit cable segregation in the order given below.
Power cables operating at 6 kV
Power cables operating at 400 volt or less
Control cables or low voltage, low power cables
Communication, instrumentation and thermocouple cables
Construction of the tray, including elbows and fittings, shall be such that 7-53 KHABAT TPP UNITS 1&2 - VOLUME I
support is provided over a minimum of 20 percent of its length to cable laid anywhere in the tray and at least 40 percent of the tray bottom is open to provide ventilation. After all cutting, punching, reaming, welding, drilling, capping and cleaning have been completed, all steel tray shall be degreased, pickled, rinsed, prefluxed and galvanized. C.
Cables below ground level Cables laid direct in the ground shall be covered with a layer of sand, with protective tiles above the sand. Tape shall be laid above the tiles to indicate the presence of cables below. Buried unarmored cables shall be mechanically protected throughout by ducts encased in concrete. All ducts and conduits shall have their ends sealed against the ingress of water and oil. Drawpits shall be positioned at reasonable intervals in long runs and changes of direction of cable ducts. Cables rising out of a duct or the ground shall be protected for a minimum of 1.5 m above the finished floor level. Preformed trenches shall be of adequate size to allow for cable trays or ladder racks to be installed on the side of the trenches, with a walkway down the centre of the trench. The trenches shall be complete with concrete covers.
D.
Conduit systems All steel conduit along with all accessories and fixings shall comply with IEC 60423 and IEC 60614. Minimum conduit size shall be 20 mm2. Conduit shall be hot dip galvanized, fittings shall be galvanized malleable iron. Steel conduit systems shall be electrically continuous. All pliable conduit systems shall comply with IEC 61386-22. Outer coverings on pliable conduit shall be low acid, self extinguishing type. All flexible conduit systems shall comply with IEC 61386-23. Flexible conduit shall be installed to vibrating and adjustable equipment, and where structural expansion occurs.
7-54 KHABAT TPP UNITS 1&2 - VOLUME I
For high temperature applications up to 260°C, non metallic flexible conduit shall be manufactured from polyketone. Conduits and ducts shall be sized to enable the cables to be easily drawn in. E.
Trunking systems Cable trunking shall be manufactured from galvanized mild steel. The coating shall comply with ISO 1461. The trunking shall be fixed 150mm from bends, angles, tees or offsets, and at intervals not exceeding 2m on straight runs. The trunking shall be provided with removable covers. Copper bonding links shall be fitted across all trunking joints. Lighting trunking shall be used exclusively for the purpose of lighting fitting suspension and the routing of directly related wiring.
F.
MI cable installation MI cables shall not be installed where they will be subject to repetitive flexing. All MI cables shall be supported throughout their length, on either side of bends, and within 300mm of the termination.
G.
Terminations PVC shrouds shall be provided over all cable glands. Cable lugs shall be the compression type. Cores of all control cables shall be long enough to allow a second termination at a future date. Screens on multicore cables shall be insulated from field instruments and cable armor and shall be connected to ensure continuity throughout their length. All cables and cable cores shall be unambiguously identified. Wiring ferrules shall be suitable for affixing to the cable cores. All MI cable terminations shall be complete with pot type seals, cold compound, glands, and high temperature neoprene sleeves. The copper
7-55 KHABAT TPP UNITS 1&2 - VOLUME I
sheaths of single core MI cables shall be earthed at one end only, insulated glands shall be used on the other ends. After both ends of the mineral insulated cables have been terminated the cable shall be subjected to an insulation resistance test. The insulation resistance shall be noted and compared with the value obtained in an insulation resistance test carried out at least 24 hours after the termination is completed. The second reading shall be a minimum of 100 MΩ. 7.16
Cathodic Protection System A complete and fully automatic cathodic protection system shall be provided in accordance with IEC or the relevant international code & standard. An impressed current system shall be preferred and shall include but not be limited to: distributed anode ground beds, transformer rectifiers, distribution panels, wiring and monitoring. Where appropriate, smaller structures may be protected by sacrificial anodes. The cathodic protection system shall be brought into operation immediately upon completion of construction of the plant to be protected. The Bidder shall undertake all necessary precautions to ensure that the current density is appropriate to guarantee protection. Particular note shall be taken of the presence of other buried services in the area of the protected plant. The Cathodic protection system shall have a design life of 25 years. The Bidder shall provide a schedule detailing all vessels, tanks, structures and submerged/buried pipelines to be protected by a cathodic system to demonstrate the adequacy of the provision. For the tanks, no cathodic protection is required as the tanks are installed on the concrete foundation; hence it has no metallic parts which are in direct contact with the soil.
7.17
Variable Speed Drives
7.17.1
Function All variable speed drives shall be of the variable frequency adjustable speed type and comply with the following requirements. The drive shall be a variable frequency solid state 12 pulse width modulated (PWM) adjustable speed converter applied to a cage induction motor, be housed in an IP 41 enclosure, and with inlet and outlet filters where necessary. The motor shall be suitably de-rated to allow for voltage and 7-56 KHABAT TPP UNITS 1&2 - VOLUME I
current harmonics developed by the converter. The motor shall be rated for continuous operation at any point throughout the speed and duty range. The converter unit shall be suitable for direct connection to the ac mains supply and shall have a regulation accuracy of ±1.0 per cent under all conditions. There shall be provision to ramp up and down to suit plant requirements. The converter equipment shall generally comply with the requirements of IEC 60146. The following harmonic distortion limits shall not be exceeded at any MV and LV main power distribution switchboard: Individual harmonic voltage
System voltage(kV) at
Total harmonic
point of common
voltage distortion
coupling
VT(%)
Odd
Even
0.4
5
4
2
11
4
3
1.75
distortion(%)
Calculated levels of harmonic distortion shall be submitted with the Tender. These calculations shall include individual drives and also the maximum number of drives connected to main power distribution switchboards. The variable speed drive shall be controlled by the plant control system without the need for interposing equipment. The converter shall be complete with all necessary control and operating circuits, instruments, alarms, isolators, contactors and circuit-breakers for remote automatic and manual control, local to motor control, and testing at the converter cubicle of the complete drive. Local control shall also be provided for maintenance purposes. 7.18
Electrical Equipment for Hazardous Areas The installation design, and the manufacture, certification and installation of electrical equipment in hazardous areas shall comply with IEC 60079. All hazardous areas shall be shown on site layout drawings.
7-57 KHABAT TPP UNITS 1&2 - VOLUME I
8
CONTROL, INSTRUMENTATION AND COMMUNICATIONS
8.1
Introduction This Section describes the technical requirements for the design, supply and installation of control and instrumentation (C&I) for an oil-fired power plant. All C&I equipment necessary to allow the safe and efficient operation of the power plant shall be supplied, installed, commissioned and tested as part of the Contract. A consistent control, instrumentation and data acquisition philosophy shall be applied throughout the power plant. The objective shall be to standardize all equipment, wherever possible, throughout the power plant in order to rationalize operation, maintenance and reduce spare parts. In general, all equipment shall be of modern compact design, incorporating proven technology and supplied from one composite range as marketed by a reputable international manufacturer. C&I shall be provided such that no single failure can cause a forced outage of the power plant. Triple modular redundant control systems (2 out of 3 voting) shall be provided for all plant safety critical control and protection systems.
8.2
Scope of Supply The scope of supply described in the document shall be the minimum necessary to achieve the required objectives and shall consist of, as a minimum, the following: A.
Complete control, protection and monitoring systems for the steam turbine generator including digital electronic governor systems, automatic run-up and loading system, turbine stress evaluator, turbine supervisory system, turbine trip system, generator control and monitoring system, generator gas systems C&I, local control stations, etc. and all auxiliary C&I equipment. It is recognized that some of the above functions may be incorporated in the Plant Control System (PCS) referred to below.
B.
Complete control, protection and monitoring systems for the steam generator including boiler controls, burner management system, boiler protection system, burner control and monitoring, boiler stress monitoring, 8-1 KHABAT TPP UNITS 1&2 - VOLUME I
furnace flame monitoring system, furnace flame camera system, drum level monitoring and protection system, boiler tube leak detection system, local control stations, etc. and all auxiliary C&I equipment. It is recognized that some of the above functions shall be incorporated into the PCS referred to below. C.
Complete control, protection and monitoring systems for fuel supply and storage system, condensate system, feedwater system, main and reheat system, feedwater heater extraction, drain & vent system auxiliary steam system, closed cooling water system, circulating system, etc. and all auxiliary C&I equipment.
D.
Complete control, protection and monitoring systems for the electrostatic precipitator, ash handling system, FGD system, sootblowing system, condenser tyube cleaning system, auxiliary boiler, compressed air system, make-up demineralizer system, chemical feed system, water treatment system, waste water treatment system, chemical dosing system sampling system HVAC, etc.
E.
Complete control, protection and monitoring systems for the station electrical systems shall be provided as specified in section 7 and elsewhere in the document.
F.
DCS(Distributed Digital Control System) based Plant Control System (PCS) including all hardware, software, operating licences and associated equipment to provide integrated control and monitoring of the overall plant from the Central Control Room (CCR). This shall be in addition to any local control and monitoring facilities required. The control and monitoring of the following systems shall be incorporated into PCS for the overall plant operation in CCR. -
Boiler, fuel supply and storage system, condensate system, feedwater system, main and reheat system, feedwater heater extraction system, auxiliary steam system, closed cooling water system, circulating water system, etc.
G. TCS(Turbine Control System) including all hardware, software, operating licences and associated equipment to provide integrated control and monitoring of the turbine-generator from the Central Control Room (CCR). This shall be in addition to any local control and monitoring facilities required. The control and monitoring of the following systems shall be incorporated into TCS for the turbine-generator operation in CCR. 8-2 KHABAT TPP UNITS 1&2 - VOLUME I
-
Digital electronic governor systems, automatic run-up and loading system, turbine stress evaluator, turbine supervisory system, turbine trip system, generator control and monitoring system, generator gas systems, etc.
H.
PLC(Programmable Logic Controller) based the following individual package control systems including all hardware, software, operating licences, program loader and associated equipment. -
Electrostatic precipitator, ash handling system,
auxiliary boiler,
compressed air system, water treatment system, waste water treatment system, chemical dosing system, sampling system, HVAC, etc. -
The PLC shall be of the same basic design and shall be supplied by one(1) recognized manufacturer having wide experience in the manufacture, application, and installation of equipment and systems. The PLC shall be selected by KNOC in order to closely coordinate with the plant PCS.
I.
Central control room / computer room / local control room equipment including operator desks, chairs, printers, DLP/DMD type large screens, digital indicators, clock, CCTV monitors, furniture, emergency push buttons, etc.. DLP cube should be possible to do front and rear side maintenance as it is installed sliding system screen which make possible to front side maintenance
J.
Emergency shutdown systems for safe plant running, shut-down and protection.
K.
Interfaces between the PCS, field equipment, packaged control systems including TCS, ECS, instrumentation, actuators, motor control centres and all associated equipment and devices. Data communication interfaces between the PCS and packaged control systems shall be dual redundant. All standalone and proprietary C&I systems shall be monitored and controlled via the PCS. All necessary hardware, software and special cables shall be supplied, installed and tested.
L.
Interfaces to the load dispatch centre and station administration LAN.
M. Condition monitoring equipment for major plant and auxiliaries. N.
All C&I and telecommunication cabling systems.
O. Plant performance monitoring system. P.
Boiler thermal stress monitoring system. 8-3 KHABAT TPP UNITS 1&2 - VOLUME I
Q. Boiler tube leak detection system. R.
Furnace temperature monitoring system
S.
Instrumentation with accuracy suitable for tariff metering of fuel supplies and electricity generated with display, trending and log reports of current and cumulative values.
T.
Gas detection system - Flue gas anlyzers(CO and O2) for combustion control
U.
Flue gas and waste water emissions monitoring equipment.
V.
Water and steam sampling and analysis equipment
W. Field instrumentation including pressure, temperature, level and flow gauges, switches, transducers and transmitters, test ports and all associated tapping points, pipe work, valves, thermowells, local cubicles, instrumet cabinets, tubes, fittings, filters, regulators and installation materials X.
Instrument power and air distribution systems
Y.
Telecommunication systems.
Z.
Clock system.
AA. Closed circuit television (CCTV) and perimeter security systems. BB. Weather station. CC. Fire detection and protection systems. DD. Electrical and instrument test equipment EE. Factory testing and inspection. FF. Site testing and inspection GG. Site erection, installation and commissioning. HH. Documentation II.
Operating and maintenance manuals, including as-built information.
JJ. Operator and maintenance staff training. KK. Spare parts (commissioning spares and two years operating spares). LL. Special tools and equipment. MM. Furnace Flame Viewing Television System 8.3
Objectives The main objectives of the C&I scheme are as follows: A.
To allow safe and reliable start-up, synchronizing, loading, shut-down, emergency tripping, control and monitoring of all major plant areas from the CCR. 8-4 KHABAT TPP UNITS 1&2 - VOLUME I
B.
To allow the optimized and efficient use of all plant areas.
C.
To maximize the availability of all plant.
D.
To incorporate a maximum level of automatic control, thereby minimizing operator manning levels, and incorporating APS(automatic plant start-up and shut-down system.
E.
To provide facilities for comprehensive monitoring, storage and presentation of information concerning plant conditions.
F.
To provide facilities for comprehensive testing and presentation of information concerning system and plant performance.
G. To centralize plant monitoring and control facilities. H.
To reduce start-up and shut-down sequence times to a minimum whilst minimizing mechanical and thermal stresses imposed on the plant.
8.4
Operational Philosophy To meet the objectives stated above the monitoring and control of the power station processes and electrical systems shall be undertaken by the use of modern and well proven microprocessor-based systems. The major items of plant, e.g. turbine generator, burner management system, etc., shall normally be provided with their manufacturer’s specialized proprietary control equipment, e.g. governor controls, generator excitation control and automatic voltage regulators, burner management system, etc. In such cases these specialized systems shall be interfaced to the PCS to enable control and/or monitoring from the CCR. However, dependent on the main plant Bidder’s design philosophy, some of these control systems may be incorporated within the PCS. The control and monitoring systems(PCS/TCS/PLC) shall be designed to have a high level of availability by the use of proven systems and the use of redundant processors, memory devices, power supplies, data communication links, etc. No single component or device failure within the C&I packages shall cause loss of generation. In case of electric power failure, control drives such as control valves, vanes, dampers, etc. shall be kept in required safe position. 8-5 KHABAT TPP UNITS 1&2 - VOLUME I
The overall co-ordination, monitoring and control of the power station plant and the main operator interface shall be via the PCS/TCS. The PCS/TCS shall be designed to have a functionally and geographically distributed architecture utilizing a number of independent controllers. These controllers shall be capable of autonomous operation and provide control, both continuous and sequential control, data acquisition and calculation facilities. The PCS/TCS shall consist of a set of microprocessor-based controllers interconnected via a suitable and reliable high speed data communications network to allow the interchange of data and control commands. The controllers shall be capable of performing data acquisition, logic, sequential and closed loop control utilizing real time data derived from plant-mounted instrumentation. Control commands shall be issued by the PCS/TCS to actuators and final drives located on the plant. The controllers shall be functionally distributed and physically located in suitable plant areas, particular care being taken to ensure that the equipment is suitable for the proposed environment. The control system configuration and associated real time data shall be resident in the system database that shall be either distributed throughout the controllers or resident in a server but accessible to all controllers and operator devices. The network shall also communicate with the Human Machine Interface (HMI) to allow centralized monitoring and operator control of the plant from the CCR. This shall be based on the use of visual display units (VDUs), keyboards and other inputting devices. The PCS shall be capable of providing control of individual drives, of sequencing a functional group of drives to an optimized program of plant operation, and of sequencing functional groups to provide full automatic plant operation. The PCS shall incorporate functions for use by the operating, engineering and management staff including, but not limited to, data historian, event and alarm 8-6 KHABAT TPP UNITS 1&2 - VOLUME I
handling, engineering and diagnostic tools, software configuration tools, plant condition monitoring and performance monitoring. Main items of plant such as the steam turbine generator, boiler, fuel systems, water treatment plant, etc. may be supplied with purpose-designed systems for control, monitoring and protection. Such systems shall be designed to function independently of each other but shall be interfaced with the PCS to allow integrated operation of the total plant. The PCS shall be fully integrated with the control, instrumentation and alarm equipment of the plant being provided, in order to maximize automation of the power plant and minimize operator manning levels. The PCS/TCS shall incorporate a high level of availability and be designed such that a single component failure shall not result in the shut down of any plant or the reduction in plant load. This shall be achieved by the equipment and component design and the provision of dual redundant power supplies, control processors and data communications equipment. Where applicable dual redundant input/output devices shall also be provided. Steam turbine generator, boiler and furnace protection shall be achieved by dedicated systems utilizing triplicated I/O channels and 2-out-of-3 voting logic. For all other plant safety critical protection systems the redundancy provided shall be in compliance with the required safety integrity level. The PCS shall be supplemented by local controls and instruments necessary for maintenance and commissioning activities and for performance testing of the plant. The PCS and local controls shall be designed such that it shall not be possible to operate any item of plant from more than one point of control simultaneously. 8.5
Control and Monitoring of Plant
8.5.1
Steam generator Comprehensive control, instrumentation, protection and alarm equipment, including automatic control systems necessary for the safe and efficient operation of the boiler and auxiliary equipment shall be supplied. The control and monitoring of the boiler and its auxiliaries shall, unless the Bidder’s 8-7 KHABAT TPP UNITS 1&2 - VOLUME I
proprietary equipment is proposed, be implemented in the PCS. The preferred method of signal interchange of non-safety critical signals between the boiler proprietary C&I systems and the PCS shall be via redundant data communications links. For safety critical signals the signal interchange shall be hardwired and its philosophy and implementation shall be subject to the KNOC’s approval. A burner management system (BMS) and boiler protection system (BPS) shall be provided. These systems shall be designed in accordance with the requirements of NFPA 85. Interfaces between each of the control systems shall be included to allow centralized monitoring and control from the CCR. The instrumentation and control shall include, but not be limited to, the following: A.
equipment to allow the monitoring and manual/automatic control of the draught, fuel, steam, feed-water, drum level and all other auxiliary systems
B.
independent and redundant emergency tripping and protection systems
C.
sequence control and safety interlocks
D.
instrumentation and control equipment for auxiliary systems, providing local and remote indication of mechanical and electrical quantities as required including fuel, feed-water, steam and draught systems, chemical analysis equipment (water and steam) and chemical injection equipment
E.
local and remote indication of control and isolating valve positions, motor loads and status for main auxiliaries
8.5.1.1 Boiler controls The basic requirements for the major boiler control loops are stated below for guidance only. The Bidder shall be responsible for ensuring all necessary control loops and associated equipment required to provide a complete operational system are provided. The boiler systems shall allow operation of the boiler in all automatic control modes between 20 to 100% BMCR without the automatic controls reverting to manual.
8-8 KHABAT TPP UNITS 1&2 - VOLUME I
A.
Boiler load
B.
Combustion air
C.
Furnace pressure
D.
Superheated steam temperature
E.
Hot reheat steam temperature
F.
Drum level control (single and three element control)
G. Feed-water flow
8.5.1.2 Burner management system A burner management system (BMS) shall be provided to protect against the unsafe admission of fuel to the furnace and to provide for the safe operation of the boiler plant from the CCR. The design of the BMS shall comply with all relevant NFPA and international standards, including NFPA 85, for boiler operation and safety considerations. The BMS shall permit the safe light up and shut down of all burners and igniters, continuously monitor the status of all burners that are operating and ensure the safe shutdown of any/all burners upon detection of fault conditions and/or the operation of a master fuel trip. The BMS shall incorporate the logic sequences required for ensuring proper purging of the furnace, completion of gas and oil headers leakage tests and starting permissives are satisfied before gas and oil burner ignition, normal shut down and for emergency tripping of the burners either individually or as a complete system. Operation of the purging sequences on start up and shutdown of the boiler shall be automatic with full status and indication in the CCR requiring no operator intervention. The operation of the burners shall be possible in both automatic and manual modes. Continuous self checking facilities shall be provided for the burner management and safety systems and alarms initiated if any self check fails. 8.5.1.3 Burner flame monitoring system A system shall be provided which individually monitors the presence or absence of a flame at each burner, separate monitors being provided for each igniter and burner. The flame monitors shall be sensitive to the specific burner or igniter flame and not to any adjacent burners or to wall radiation. 8-9 KHABAT TPP UNITS 1&2 - VOLUME I
The flame monitors shall be of robust construction and suitable for interfacing to the BMS. Any necessary cooling and protection systems required shall be supplied, with monitoring systems to notify any failures to the PCS. The CCR operator shall have access, via the PCS, to all burner information for monitoring the status of sequences and monitoring loops. Continuous self checking facilities shall be provided for the burner flame monitoring systems and alarms initiated if any self checking systems fail. The flame detector assemblies shall be mounted such that they are easily accessible for maintenance and removal. 8.5.1.4 Boiler protection system The boiler protection system (BPS) shall protect the boiler and furnace against the occurrence of explosion, implosion or other catastrophic events whether due to operator action, plant failure or failure of the control systems.
The
extent of the causes of such occurrences shall be subject to approval during the design phase but typically would consist of the following: A.
Manual trip
B.
Drum level HiHi or LoLo
C.
Drum pressure HiHi
D.
Furnace pressure LoLo
E.
Furnace pressure HiHi
F.
Air flow < x% full load airflow
G. Loss of both CID fans H.
Loss of both FD fans
I.
Loss of boiler circulation
J.
Loss of both air heaters
K.
Total flame failure
L.
Partial loss of flame leading to a hazardous situation
M. Turbine trip with steam bypass out of service N.
Electrical system trip
To provide high levels of reliability, duplex and triplex signals shall be provided, using individual tapping points, individual sensing elements and individual 8-10 KHABAT TPP UNITS 1&2 - VOLUME I
signal cables. Data interchange to the PCS shall be via dual redundant serial data links with critical signals hardwired. Facilities shall be provided for the on-load testing of the trip system. 8.5.1.5 Furnace flame viewing television system A flame viewing television system shall be provided to monitor the main burner and igniter flames. Minimum two color cameras per boiler shall be installed in the furnace wall viewing the flames through suitable lens tubes and the resulting image displayed on a monitors in the CCR. The cameras shall be of robust design specifically designed for the purpose of furnace flame viewing with suitable cooling to protect the equipment from the extreme local environment. They shall also be protected against the ingress of dust and moisture, varying temperature and humidity and high vibration levels. The design shall allow easy access and removal for maintenance. The lens, viewing tube and the associated equipment shall be designed to ensure settlement of dust and debris on the lens is minimized. Compressed air shall be used for keeping the camera lens clean. 8.5.1.6 Burner local control panels Local panels shall be supplied adjacent to each burner position to provide local manual control of burner light off, operation and trip/shut down. Local controls shall also be provided to open and close the burner air registers Selection of local or remote operation shall be at the local control panel. The extent of local monitoring and controls shall be to the approval of the KNOC. All interlocks and permissives from the BMS, BPS and unit protection system shall be operational in both local and remote mode of operation. 8.5.1.7 Boiler drum water level Due to the safety critical issues associated with boiler drum level control and monitoring, special facilities shall be provided for local and remote indication, alarm, tripping and control. The Bidder’s proposed drum water level monitoring systems shall be to the approval of the KNOC. Three level transmitters shall be provided at each end of the drum to provide 8-11 KHABAT TPP UNITS 1&2 - VOLUME I
alarm and tripping functions. Each transmitter shall have independent tapping points, impulse pipework, cables and processing equipment. Alarm and tripping signals shall be derived using 2-out-of-3 selection. The transmitters shall also be used for control, indication and alarm purposes via the PCS, the average of the median values from each end of the drum being used. The tripping functions shall be independent of the control, indication and alarm functions (i.e. malfunction or failure of the PCS shall not affect the integrity of the tripping functions). A local, direct reading, drum level gauge glass shall be provided at each end of the drum to allow local monitoring of the water level. The gauge glass shall incorporate a lighting system to allow observation of the level at low ambient light levels. To provide remote indication of drum level in the CCR, a conductivity type level instrument, e.g. a Hydrastep system, shall be provided at each end of the drum with individual displays at the associated unit panel. Local displays shall be provided at each end of the drum. 8.5.1.8 Boiler thermal stress monitoring system A boiler thermal stress calculation and lifetime calculation package shall be provided using signals from temperature points on the drum, headers, walls, etc. This package may be run on a standalone system or form part of the PCS. If a standalone system is proposed a data link to the PCS shall be provided to allow the CCR operator full access to the data. 8.5.1.9 Boiler drains The control and temperature monitoring of the principle boiler drains shall be provided. The information shall be displayed and recorded on the PCS. 8.5.2
Steam turbine Comprehensive control, instrumentation and alarm equipment, including automatic control systems necessary for the safe and efficient operation of the steam turbine and auxiliary equipment shall be supplied and integrated with the TCS(turbine control and monitoring systems) for normal operation and supervision remotely from the CCR.
8-12 KHABAT TPP UNITS 1&2 - VOLUME I
Interfaces between the TCS and the PCS shall generally be via a redundant serial data communications link except for safety critical signals(control signals, SOE) which shall be hard-wired. The extent of hardwiring of critical signals between the steam turbine and the TCS shall be subject to approval. The design of the control systems for the prevention of water ingress shall be in accordance with ASME TDP-1. The TCS shall include, but not be limited to, the following: A.
Redundant
automatic
turbine
governor
controls
and
associated
equipment B.
Independent
and
redundant
(triplicated)
emergency
tripping
and
protection systems C.
Sequence controls and interlocks (e.g.
pre-start checks, start-up, shut-
down, etc.) D.
Machine condition monitoring and turbine supervisory equipment including vibration monitoring system, rotor eccentricity, speed, casing differential expansion, thrust bearing wear, etc
E.
Turbine stress evaluation and machinery protection systems;
F.
C&I for auxiliary systems, providing local and remote indications of mechanical and electrical quantities as required;
G. Local and remote indication of control and isolating valve positions, motor loads and status of main auxiliaries; H.
Remote and local alarms.
Control processors and instrumentation shall be provided such that no single failure can cause a forced outage. To this end dual redundant and triple modular voting systems shall be used as appropriate throughout the control and instrumentation system design. 8.5.2.1
Digital electro-hydraulic governor (DEHG) The DEHG system shall be designed to control the turbine generator speed and load by controlling the turbine governor/intercept valves. The governor system shall employ triple redundant speed sensors, pressure sensors, etc and use a triple modular architecture to ensure high reliability and immunity to single faults. The redundant parts of the system shall be segregated to 8-13 KHABAT TPP UNITS 1&2 - VOLUME I
minimize the effects of common mode faults. Comprehensive test and self diagnostic fault protection features shall be provided,
including
on-load
testing
of
the
DEHG
system
and
governor/intercept valves. 8.5.2.2 Turbine protection system A dedicated turbine protection system shall be provided. The extent of signals shall be subject to approval during the design phase but shall typically be as follows: A.
Manual trip (local and remote)
B.
Overspeed trip (mechanical - duplex)
C.
Overspeed trip (electrical - triplex)
D.
Bearing oil pressure LoLo (triplex)
E.
Condenser vacuum LoLo (triplex)
F.
Excessive thrust wear (triplex)
G. Bearing vibration HiHi (triplex) H.
Control oil pressure LoLo (triplex)
I.
Governor/intercept valve failures (triplex)
J.
Governor control failure (triplex)
K.
Generator/electrical trips (duplex)
L.
Steam generator trips (duplex).
To provide high levels of reliability, duplex and triplex signals shall use individual tapping points, individual sensing elements and individual signal cables. Cables shall be routed separately to minimize common mode failures. Data interchange to the PCS from TCS shall be via dual redundant data links with critical signals hardwired. Emergency stop push buttons shall be provided remotely on operator console in CCR. Facilities shall be provided for the on-load testing of the trip system. The tripping philosophy and its implementation shall be to the approval of the KNOC. 8.5.2.3 Automatic run-up and loading (ARU) 8-14 KHABAT TPP UNITS 1&2 - VOLUME I
The ARU system shall be designed to ensure consistent turbine run up control from barring speed to full speed at maximum rates compatible with the thermal state of the turbine, the steam conditions applied and the allowable expenditure of turbine life expectancy. The design of the ARU shall take full account of: A.
All necessary pre-start checks to ensure minimum conditions for auto runup initiation are satisfied
B.
Calculation of run-up rates and critical speed bands
C.
Automatic synchronization and loading
D.
Turbine load limiting during initial start-up and during on-load operation
Facilities shall be provided via the TCS to allow the operator to monitor the operation and status of the ARU sequence and interrupt the automatic run-up at any point and complete the run-up under manual control. Irrespective of the mode of control, automatic or operator initiated, all protective interlocks shall be operable. 8.5.2.4 Turbine stress evaluator (TSE) The TSE shall monitor, evaluate, predict and record the stress values for the turbine rotors and provide lifetime calculations. Temperature measurements shall be taken of the turbine cylinder inner walls and the surface temperatures of the rotors inferred. From these measurements stress values for the rotors shall be predicted and used to assist in achieving efficient run-up and loading of the turbine within agreed stress limits. The TSE may be of a proprietary design or be implemented in the TCS. If a proprietary design is proposed, dual redundant data links to the TCS shall be provided to enable the TCS to monitor the TSE. 8.5.2.5 Turbine supervisory system The turbine supervisory system shall include, as a minimum, the following measurements: A.
Turbine speed
B.
Shaft eccentricity
C.
Shaft vibration at each main bearing measured in two planes displaced by 90 degrees 8-15 KHABAT TPP UNITS 1&2 - VOLUME I
D.
Differential expansion between the inner turbine casings and the rotors
E.
Thrust bearing wear
F.
Valve positions ( stop, governor and intercept valves where applicable).
G. Thrust bearing metal temperatures H.
Bearing metal temperatures
I.
Bearing oil temperatures (return line).
Dual redundant data links to the TCS shall be provided to enable the TCS to monitor the supervisory system from the CCR. 8.5.2.6 Turbine drains The control and temperature monitoring of the principal turbine drains shall be included. Monitoring shall be via the TCS. 8.5.3
Generator Comprehensive control, instrumentation and alarm equipment, including automatic control systems necessary for the safe and efficient operation of each electrical generator shall be supplied. These shall be integrated with the TCS for remote operation and supervision from the CCR. The controls shall enable the generator to meet the optimum output achievable under steady state and changing load conditions while maintaining safe conditions and high levels of efficiency. The control and instrumentation shall include, but not be limited to, the following: A.
Automatic controls and associated equipment.
B.
Generator excitation controls, Automatic Voltage Regulator (AVR).
C.
Synchronising equipment (automatic and manual).
D.
Emergency tripping and protection systems.
E.
Sequence controls and interlocks (eg synchronizing, shut-down, etc).
F.
Local and remote alarms.
G. Generator controls and instrumentation 8.5.4
Auxiliary plant Unless otherwise specified, the manufacturer’s standard packages of control 8-16 KHABAT TPP UNITS 1&2 - VOLUME I
and instrumentation shall be supplied for all auxiliary plant. Protection systems shall be independent of the control system for that plant. Equipment shall be supplied to interface all auxiliary plant with the PCS to enable normal control and supervision of the system remotely from the CCR. The PLC is microprocessor-based on control and monitoring system which is used for control and monitor of manufacturer’s standard package system such as EP, ash handling system, FGD system, sampling system, soot blowing system, condenser tube cleaning system, air compressor system, auxiliary boiler, make-up demineralizer system, chemical feed system, hypochlorination system, waste water treatment system, HVAC system, etc. The PLC shall be of the same basic design and shall be supplied by one(1) recognized manufacturer having wide experience in the manufacture, application, and installation of equipment and systems. The PLC shall be selected by KNOC in order to closely coordinate with the plant PCS. The PLC shall be provided with redundant CPU's, power supplies and networks. The Bidder shall provide the interface devices(Ethernet hub), media converter, and fiber optic cable for data communication between PLC(except HVAC) and the PCS. The communication link shall be redundant. The Bidder shall provide the LCD monitor based operator interface station(HMI) for each manufacturer’s standard package system. The LCD station shall be panel mounted draw-out type or separated desk-top type in local control room. The LCD station shall consist of industrial PC including CPU, main memories, communication interface equipment for PLC, power supplies and auxiliary memories(hard disk, floppy disk, etc), and peripherals such as LCD/Keyboards, mouse, printer. The LCD monitor base on desk-top type shall be dual type in local control room The Bidder shall submit the PLC configuration drawings for each manufacturer’s standard package system. This shall be supplemented with local controls, gauges and other devices to allow local maintenance and testing activities where required. The control and instrumentation systems for the common systems shall be 8-17 KHABAT TPP UNITS 1&2 - VOLUME I
designed, manufactured and installed to the same standards as that provided for the main plant. 8.6
Plant Control System
8.6.1
General system design A fully integrated Plant Control System shall be PCS(distributed digital control system) and provided to monitor, control, display, alarm and record selected physical and electrical parameters associated with all plant areas. Where appropriate, the system shall have a functionally and geographically distributed architecture utilizing a number of independent outstations or nodes containing control processors, power supplies, data communications systems, marshalling and termination facilities. The PCS shall be capable of autonomous operation and perform data acquisition, calculation, open loop, and closed-loop control functions. Communications between the nodes located in different plant areas and the Operator's Workstations (OWS) or Engineer's Workstations (EWS) shall be performed over suitably designed, redundant, high-speed, serial data highways. The communications system shall be designed to perform at the speed necessary to ensure that all variables are updated and control commands are issued without loss of system performance. The communications system shall include all control equipment, error detection/correction facilities and cabling. The PCS shall be designed to ensure maximum availability by the inclusion of built-in redundancy for both hardware and software. This shall include duplicated control processors, data highway and power supplies with automatic changeover to the standby unit upon detection of a fault or failure of the operating unit. The failure of any single element shall not affect the operation of any item of operating plant. In particular, the duplicated control processors shall be capable of change-over without change to plant status, sequence status or control actions, at any stage of plant operation. The PCS shall be designed to have an availability of 99.98 per cent or better by the inclusion of built-in redundancy for both hardware and software. This shall include redundant control processors, data highways and power supplies with automatic changeover to the standby unit upon detection of a fault or 8-18 KHABAT TPP UNITS 1&2 - VOLUME I
failure of the operating unit. Redundancy is required for all input and output modules used for safety critical control or protection functions. The failure of any single element within the PCS shall not affect the operation of any item of operating plant. Comprehensive system diagnostics shall be incorporated to assist in maintenance and trouble-shooting. These shall include memory, control processors, I/O cards, data highway, and storage devices as a minimum. The PCS shall be synchronized to the plant master clock system. All necessary hardware for marshalling and terminating incoming and outgoing plant cabling shall be provided. This shall include gland plates, glands, terminal blocks, intrinsic safety barriers, isolation devices, labelling and wiring. Equipment shall be designed to operate in hazardous areas where necessary. The PCS shall be immune to electromagnetic interference (EMI) and radio frequency interference (RFI). 8.6.1.1 Input/output system A.
The I/O system shall be capable of supporting process signals from all types of sensors and contact devices without requiring external or auxiliary signal conditioning devices. All input/output signals shall be decoupled in a suitable way with software filtering for each analog or digital card. The design of I/O sections shall allow easy separation of the field wiring during the loop checkout. This section shall protect the I/O circuits from transient and limit damage to a single I/O points or I/O card. Failure of any I/O card shall not affect any other loops in the controller. I/O section shall also perform self-diagnostics and provide error and alarm status on the LCD monitor. The Bidder shall guarantee that accidental connection of non-instrumentation voltages or electrical interference shall not damage the system electronics or cause incorrect encoding data.
B.
Standard I/O modular, "plug-in" components shall be provided.
Field
wiring shall be terminated in screwed or maxi terminal block and interconnected to the processor I/O system. Each type of I/O modules 8-19 KHABAT TPP UNITS 1&2 - VOLUME I
shall be arranged on a plug-in printed circuit board so that in case of failure of the board, the number of concerned I/O is minimum. Replacing one board shall concern a minimum of I/O. C.
The Bidder shall make provisions for terminating and grounding individual shield and overall cable shield wires. These shield wires shall be grounded properly.
D.
All analog inputs shall be separately isolated. And digital inputs and outputs shall be optically isolated.
E.
The isolation of the interfacing signals shall be made by Bidder's system.
F.
Input/Output cards shall meet the following requirements, but not be limited to : 1) Analog input card Passive or active 4-20mA, generally 24V DC, loop power for 420mA, 2-wire transmitters shall be furnished by the control system 2) Analog output card Capable of driving up to 600 ohms total loop resistance at 4-20mA, 24V DC loop power shall be furnished by the control system. The load impedance for smart type valve positioner shall be maximum 1.2k. 3) Digital input card Capable of receiving 24V DC as input "1" and open circuit (infinite resistance) as "0". Generally, sense voltage(24V DC) to field contacts shall be provided by the control system. The system shall provide the following features for the Sequence of events (SOE) input a. The system shall provide a digital fast scan for the quantity of high speed sequence of events alarm contacts. b. All SOE inputs shall have the attributes of digital c. The Bidder shall provide with a maximum system-wide resolution of 1 msec between events. d. The Bidder shall supply the same contact sensing voltage as 8-20 KHABAT TPP UNITS 1&2 - VOLUME I
for SOE contact inputs. If the proposed system have independent SOE input module. The SOE signals shall be separated from control signal via hardwire. 4) Digital output card Digital outputs shall be fitted when needed with interposing relays with isolated contact of a switching capacity adapted to the load of the connected device. 5) Periodic input card Capable of receiving a zero based pulse or rectangular wave or sinusoidal wave form with amplitude of 1-10 volts and rate of 050,000 pulses per second. B. Conversion accuracies (A/D, D/A) shall be as follows : 1) Resolution : 12 bits 2) Linearity : ± 1 least significant bit (LSB) 3) Repeatability : ± 1/2 LSB 4) Accuracy : ± 0.1% full scale range over entire operating temperature range
8.6.1.2 Distributed process controller A. Distributed process controllers shall be of microprocessor based electronic modules for closed loop controls, open loop controls and interlock and for interfacing with the system communication channel. The controllers shall functionally perform closed loop control, open loop control, sequence control, data acquisition, sequence of events and alarming applications. The controller shall be functionally distributed, highly modular and arranged in a hierarchical structure closely reflection the functional grouping of the plant equipment to be controlled. All process controller shall not be loaded greater than 60% (i.e. have 40% idle time) and have 40% spare memory, except standardized modular type drive level controller, after performance test. B. Redundant requirements for the process controllers In order to ensure the highest system availability, the system shall be configured such that no single component failure, with the exception of individual I/O module, can prevent a necessary control action or cause any part of the system to become unavailable. All process controllers shall be provided with full redundant controller. Each of these full redundant controllers shall also be provided with its 8-21 KHABAT TPP UNITS 1&2 - VOLUME I
own dedicated communication controller for interfacing with the system bus. Either primary or backup controllers shall connect with data highway so that each controller can maintain fault-tolerance through redundant data highway even if either the primary or backup controller may be failed. The full redundant requirements mean that at the minimum the following components consisting of a controller shall be redundant : CPU, power supply, communication card, memory, I/O handler and etc.. The redundant controllers shall access simultaneously the field data and if one(1) controller fail, the other controller can perform automatically the functions of controller without bump. C. Grouping of process controllers The grouping of process controllers shall be detailed out and shall meet the following requirements : 1) Independent and dedicated controllers(main controller) including I/O cards, devices and other hardware shall be provided. Each controller shall be provided with its own dedicated communication controller for interfacing with the control system bus. 2) Intermixing of hardware between any two groups shall not be acceptable basically. The I/O points and control function shall be grouped functionally and physically on the basis of the train concept. For example, I/O and controller module for BFP-A shall be separated from those of BFP-B. The functional separate design is to facilitate the failure of one controller of I/O card will not affect the group of equipment performing the same function. However, The splitting of any of the groups is required due to limitation of controller capability with respect to number of inputs/outputs, controller reaction time, etc., as specified elsewhere, the same can be done by providing more than one set of controllers(main and hot backup) for such groups. Such splitting of groups shall be subject to Customer's approval and without any price repercussions whatsoever. 8.6.1.3 Data communication system A. The data communication system shall have multiple branches having fault tolerance through redundant highway system and redundant electronics. Transfer to the back-up communication channel shall be automatic without disturbing the system operation. Each communication 8-22 KHABAT TPP UNITS 1&2 - VOLUME I
unit shall be micro-processor based on. B. Communication of the PCS shall be ensured by the redundant internal communication network. The design of this network shall make full use of optical fiber and optical technology in order to achieve high immunity to electromagnetic noise and highly resistant galvanic insulation. The use of armored cable shall be accepted inside a signal cabinet or between two adjacent cabinets. C. The communication network and sub-network such as remote I/O network shall use high speed, reliable communications protocols designed for real-time process control between controllers/ between controller and remote I/O. D.
The fault-tolerance through redundant data highway communication network shall provide full connectivity with corporate LANs, WANs, and Internet, such as, combining control and enterprise information systems with high speed used by Fast Ethernet.
E. The redundant networks shall automatically and continuously be checked for operability. No manual intervention shall be required to perform this check or to restore operation to a previously faulted network after completion of repairs. F. Noise and hardware failure shall not cause erroneous information to be accepted in the message received. Self-diagnosis shall provide system status to the operator. Alarm and appropriate protection shall be carried out automatically. The monitoring and the preventive and corrective maintenance of internal communication shall be carried out through the Engineer station. G. All communication systems shall be designed and operate with a load no more than 50 % under the worst condition. H. The Bidder shall have a responsibility for the establishment of data communication link between PCS and foreign devices(TCS or PLC) including all hardware, software and technical service for the communication interface. 8.6.1.4 Power supplies A. The Bidder shall provide the fully redundant power supply units 8-23 KHABAT TPP UNITS 1&2 - VOLUME I
operating in parallel(diode actioneered) to feed DC power sources for process controllers, I/O cards, field transmitters, interposing relays, etc., so that no single failure, either of power source or power supply unit, or the restoration of the failure, shall degrade or interrupt the normal functioning of any part of the PCS. B. For system peripherals such as OIS, information system, LCD monitor /keyboard, etc., the Bidder's system shall automatically transfer to the redundant power supply. This automatic transfer shall not cause disruption to the equipment function. C. Power supplies should be sized to cover all cabinet space. In addition, the Bidder shall provide independent power distribution panel(s) to feed power the solenoid valves for AC/DC. D. The Bidder shall furnish distribution panel(s) to supply power for PCS, solenoid panels and peripherals, etc. E. All power supplies shall be equipped with a short-circuit protection feature. For the purpose of plant safety, when the control power of PCS is fail, it shall be monitored and connected by hardwire to actuate MFT. F. DC Power Supplies The Bidder shall provide all necessary DC power sources and segment distribution of this power throughout the PCS. The DC power supplies shall be provided in following way : 1) Power supplies must be of a nominal size and capable of handling a 25 % steady-state overload vs. design load. 2) The surge protection feature on the power input shall also be included. 3) Provisions shall be made on easy access and replacement to enhance convenient maintenance. 4) The ripple of each output voltage shall not exceed 5% peak to peak for main and auxiliary 24V DC power supplies under full load condition. 8.6.2
Automatic plant startup/shutdown control (APS) A. Plant automatic operation program shall proceed according to break points. The break points represent the main mileposts of the plant automation sequence. The break points or mileposts of plant operation 8-24 KHABAT TPP UNITS 1&2 - VOLUME I
program, once start, shall step forward according to the sequence of the break points. B. The startup and shutdown of the plant shall be carried out by sequential progress of the break points. A "hold" function is provided to facilitate operator intervention to stop any sequence in progress in order to carry out an investigation of a suspected malfunction. C. The degree of automation is to be such that the total time required for starting/stopping, the quality of key control parameters, and the protection of the unit shall be made by automatically controlled system, not operator intervention. The automation program shall be equipped for the cold startup, warm startup and re-startup. D. The automatic plant startup and shutdown sequence(APS) shall have all the break points for boiler and turbine startup and shutdown. The BOP systems such as circulating system, condenser air removal system, condensate system, feedwater system, main and reheat steam drain system,
feedwater
heater
extraction/drain/vent
system,
etc.
and
necessary package systems such as FGD system, EP system, Ash handling system, etc. shall be automatically started and stopped by means of command signals from the APS. The APS shall allow manual initiation of each step in above sequences as well as automatic sequencing. The shutdown sequence shall be the reverse of the startup sequence. 8.6.3
Operator’s facilities Operator’s workstations shall be provided in the CCR to allow monitoring, control and adjustment of plant conditions via high resolution “Windows” style graphics displays. All dual visual display units (VDUs), keyboards, printers, peripheral devices, and their associated control desks shall be supplied. Each operator workstation shall be arranged for an operator to monitor and control each generating unit, their auxiliaries, the common auxiliary plant and the electrical systems. The CCR shall contain a minimum of three(3) OWS for PCS and two(2) OWS for TCS per generating unit, , each OWS consisting of two high resolution colour min. 21” dual VDUs, a single keyboard and a cursor positioning device. 8-25 KHABAT TPP UNITS 1&2 - VOLUME I
The resolution of the VDUs shall be 1280 x 1024 pixels or better. Furthermore, one(1) OWS shall be provided for the common plant. Additional OWS shall be provided for accessing archived data, plant performance monitoring data etc. The workstations shall have the capability of being configured as either an Operator’s Workstation or an Engineer’s Workstation (EWS) through different passwords and shall be the main facility for monitoring and controlling the whole plant. The final quantity of equipment and the layout of the CCR shall be subject to the KNOC’s approval. A single EWS shall be provided for each generating unit although each workstation shall be capable of accessing all data and software for the total plant. Printers shall be provided for generating hard copies of alarm and event lists, screen displays and reports. All printers shall be industrial quality and complete with stands, interconnecting cables, paper trays, acoustic enclosures and all other accessories. The final quantity and type of printers shall be to approval. As a guide however, the following shall be included as a minimum: Per generating unit for PCS 1 color laser printer for screen displays 2 black and white printers for alarm/event and other reports Per generating unit for TCS 1 color laser printer for screen displays 1 black and white printers for alarm/event and other reports Common auxiliary plant for PCS 1 color laser printer for screen displays 1 black and white printer for alarm/event and other reports Per EWS 1 color laser printer. Additional printers shall be provided for other functions such as the Performance Monitoring equipment, Turbine Stress Evaluator etc. as required. 8-26 KHABAT TPP UNITS 1&2 - VOLUME I
The CCR control desks shall be provided to support the OWS and accessories. They shall be of a co-ordinated rigid design and of robust construction. Surfaces suitable for mounting the VDUs, keyboards, telephones and all other devices shall be included in the design. The control desks shall be ergonomically arranged, suitable for operation by the minimum number of operators and consistent with the plant operating philosophy. Access must be possible by more than one operator in the event of special operations and for training purposes. The control desks shall include in their construction, facilities in the desk top and the base of the units to route cables from VDUs, keyboards, telephones, etc. Lockable drawer/storage space, levelling and fixing devices shall be incorporated into the design. A suitable number of fully adjustable swivel chairs shall be provided (as a guide, a minimum of one chair per workstation plus one additional chair shall be provided) together with all necessary CCR furniture. Plant emergency stop pushbuttons shall be located on the desks provided with flap/covers to prevent inadvertent operation. The switches shall be keyresettable. The Bidder shall provide with his bid submission, a drawing showing the proposed layout and locations of equipment within the CCR and the associated equipment rooms. 8.6.4
Engineer’s workstation The EWS shall be provided for fault finding and software programming. All necessary hardware and software shall be provided to allow engineering staff to trace faults in the system and applications software, to create control strategies, VDU screens and all other maintenance activities. Software configuration and modification shall be done off-line and with the capability for testing before downloading to the control processors. The EWS shall consist of a high resolution VDU, keyboard, input device (e.g. mouse, trackball etc.) mounted on a suitable desk matching the Operator‘s Workstation in appearance. A colour laser printer shall also be provided for each EWS. The EWS shall be connected to the PCS via a data highway to allow access to system and applications software and to live plant data. 8-27 KHABAT TPP UNITS 1&2 - VOLUME I
Access shall be password protected. 8.6.5
System response times for OWS The response times for the OWS under normal conditions shall be as follows: A.
The time between selection and display of a VDU, fully updated, from the database shall not exceed 1 second with a typical workstation loading.
B.
The time between execution of a control function on an Operator’s workstation and the command reaching the output terminations of the outstation shall not exceed 1 second.
C.
The time between the occurrence or change of a signal at the origin and the change of state, value or alarm showing on the VDU shall not exceed 1 second.
8.6.6
Response times for PCS/TCS A. The PCS, as finally configured and installed, shall exhibit response times which do not adversely impact the operation of plant equipment nor impede the operator's response to events. To this end, the maximum times defined within this specification shall not be exceeded. B. Control response time for PCS shall not exceed the following values : 1)
Slow loops
: 250 to 1,000 msec
2)
Fast loops
: 50 to 250 msec
3)
Discrete/logic control
: 250 to 500 msec
4)
Sequence control
: 500 msec
5)
Protective logic(unit protection, : 1 to 250 msec burner control, etc.)
6) 8.6.7
SOE(sequence of events)
: 1 msec
Spare capacity The PCS/TCS/PLC shall be supplied with all hardware, system and applications software (VDU displays, alarms, etc.) fully developed, tested, debugged and installed for all analogue and digital I/O’s. An overall further 20 per cent spare equipment shall be provided including all necessary hardware and associated wiring, supplied and tested. Software shall be designed so as 8-28 KHABAT TPP UNITS 1&2 - VOLUME I
to ensure no degradation in the specified performance with the system fully loaded including the spare capacity. 8.6.8
Software
8.6.8.1 General The latest version of the manufacture’s operating system software shall be provided fully developed, tested and installed. The application software and associated displays, reports, databases, etc, shall be configured and fully tested when installed at site. The creation or modification of displays, reports, databases or control strategies shall be possible with the system on-line by the KNOC’s engineering personnel without affecting the plant operation. Modifications to the software shall be done in straightforward and logical steps using, wherever possible, graphic displays. It shall not be necessary to have specialist knowledge of the underlying software in order to carry out modifications. All necessary software licences shall be included. This shall allow unrestricted use of all specified software packages by the KNOC. Access to software and application programs at various levels shall be possible by operating or engineering personnel using passwords. This shall protect the software from unauthorized access. Any changes to software, either application and/or operating, shall be fully documented in a logical and structured manner in such a way that the history and nature of the changes can be easily identified. 8.6.8.2 Operator interface software The operator interface software shall enable the Operator to carry out the necessary actions in a safe and efficient manner. In particular the following features shall be included, as a minimum: A.
Software shall be structured in such a way so as to provide a hierarchy of control from automatic sequential plant start-up through to manual control of an individual item.
B.
During manual intervention by the Operator (sequence initiation and individual device control under normal and failure conditions), all software 8-29 KHABAT TPP UNITS 1&2 - VOLUME I
derived, hardwired permissive and overrides shall be visible to the Operator. C.
Where process measurements have been duplicated for improved reliability, the signals shall automatically switch to the good signal in the event of a fault. The Operator should have, for the purposes of maintenance, the on-screen facility to select either signal or the average, as the measured variable for control.
A philosophy shall be developed to define the action of the sequence logic in the event of a step failure, Operator intervention or the initiation of a sequence with not all plant conditions satisfied. It shall be possible to bypass a required plant condition but this action shall be alarmed and logged. The philosophy of operation shall be to the KNOC’s approval. 8.6.8.3 Reports The PCS shall be capable of presenting to the Operator, pre-defined reports. The information on the reports may be either in tabular form or in a preformatted report form and may be automatic at specific times or on request. Reports shall include periodic logs, daily logs and group logs, balance of energy and efficiency log. In addition, environmental reports shall be produced to meet the requirements of the local government agency. All reports shall be configured and report formats shall be to the approval of the KNOC. The facility for the operator to generate specific reports as required shall also be provided. 8.6.8.4 Alarm management All plant and system generated alarms shall be prioritized, logged and displayed by the PCS. There shall be a dedicated alarm display, which shall show all of the plant alarms or groups of alarms. The Operator’s attention shall be drawn to the occurrence of an alarm by a suitable audible and visual alarm at the CCR desk. Alarms shall also be printed on the alarm/event printer. The Operator shall have the facility to select optional alarm displays, summary of alarms, historical alarms (global or point based), unacknowledged alarms, alarms by priority, alarms by predefined system groups. There shall be a facility to suppress an alarm or groups of alarms as a result of 8-30 KHABAT TPP UNITS 1&2 - VOLUME I
a particular alarm or other plant condition in order to minimize the number of alarms under transient conditions. All alarms generated from either analogue or digital I/O shall be configured with an adjustable dead band. The value of the dead band shall form part of the configuration software. 8.6.8.5 Data logging and trends The PCS shall incorporate long term data logging facilities for all analogue, digital, serial data, alarms, condition monitoring and other internally generated points including the overall extension capacity specified. Data shall be stored for up to 12 months on a suitable storage medium and an alarm generated to inform the Operator when the storage medium approaches 75 percent of its maximum capacity. All data shall be automatically archived and retained for future reference in either optical or magnetic medium. The operator shall have the facility to display real time data, recall data held in the data logger memory or from archives over a specified period of time. The requested information may be displayed on the Operator’s workstations either in tabular form or as selected variables on a trend display. It shall be possible to compare on the same display, multiple trends of real-time data or historical data from the data logger or archives. The format and content of the reports for data retrieval from the logging facility shall be subject to approval by the KNOC. 8.6.8.6 Sequence of events A sequence of events (SOE) recording system shall be supplied to allow analysis of the causes of trips or plant disturbances. The plant SOE shall be integrated within the PCS. The SOE shall scan all agreed binary inputs continuously with a resolution of 1 ms. The status of each point shall be time tagged and stored in a database together with other relevant information for a specific time period. Data will be continuously deleted from the database on a first-in, first-out basis after the specified time period has elapsed. Facilities shall be provided for the data to be archived for future reference, and for easy retrieval for viewing and analysis.
8-31 KHABAT TPP UNITS 1&2 - VOLUME I
On the occurrence of a nominated event e.g. turbine trip or manual initiation from the PCS, all data for a specified time period before the event shall be retained and continue to be recorded for a period after the event. The SOE shall automatically reset after the elapsed time period and continue to monitor the plant in the normal way. SOE reports shall be generated and printed using the stored data and shall be used for post trip review and analysis. The report shall be presented in a clear and logical format and clearly indicate the “first cause” of the event. 8.7
Metering Metering shall be provided for process control, performance monitoring and emissions monitoring. Data shall be derived from plant instruments designed and installed to measure actual values and shall be corrected where necessary for variations in pressure, temperature, density etc. All measurements shall be displayed locally and monitored, displayed and logged by the PCS. Facilities shall also be provided for integrating the instantaneous values over a pre-defined time period. Metering shall be supplied to include but not be limited to the following: A.
Volumetric, mass and energy flow of fuel onto site and to each steam generating unit,
B.
Raw water flow,
C.
Electrical power (active and reactive) from each generator,
D.
Total electrical power (active and reactive) imported and exported from/to the Grid,
8.8
E.
Feed water, steam, condensate flows,
F.
Effluent discharge flow.
Condition Monitoring Comprehensive condition monitoring facilities shall be provided for all areas including turbines, generators, boilers and major items of plant (e.g. cooling water pumps, feed water pumps, condensate extraction pumps, cooling tower fans etc.). All necessary hardware and software shall be provided including field transducers, processing equipment, cabling, computer, printer and 8-32 KHABAT TPP UNITS 1&2 - VOLUME I
software package. The system shall be designed to monitor, display and record specific parameters associated with the general mechanical condition of the plant such as vibration, bearing temperatures, winding temperatures etc. The software package shall be designed to highlight deterioration in the condition of the plant by assessing the changing trends in the plant parameters. The software shall also take into account external influences on the plant (eg number of starts, hours run etc.) and raise an alarm when limits are approached or are about to be exceeded. The measured parameters shall be recorded and made available for analysis at a later date and for archiving purposes.
Recall of the data shall be
available either in tabular or graphical (trend) display form. Suitable hardware and software shall be provided for this purpose. The condition monitoring system shall be provided fully configured and operational. 8.9
Plant Performance Monitoring Facilities shall be provided to enable the performance of the plant to be continually monitored based on real time data derived from the PCS. The equipment shall consist of a suitable desk-top PC or OWS and printer running software designed to calculate, display and report on the performance of the overall plant and specific plant areas (e.g. steam water systems, boiler efficiency, heat rate etc). The system shall generate reports for analysis by management, engineering and operating staff identifying specific plant values such as MW, MVAr, fuel usage, etc and calculated values such as heat rate, efficiencies etc. The facility shall be computer-based and shall include all necessary hardware, software, data-inputting and interconnection with other plant equipment to form a complete and working system. It shall utilize real-time data derived directly from the PCS via suitable data communications medium and shall employ non-linear optimization techniques. Additional facilities shall be provided to allow operating, engineering and management staff to carry out on-line and off-line optimization of the power 8-33 KHABAT TPP UNITS 1&2 - VOLUME I
plant. Use of this facility shall not directly affect the operation or control of the power station. The optimizer shall be complete with its own printer for generating reports, data schedules, diagrams etc as required. 8.10
Emissions Monitoring Continuous emission monitoring equipment shall be provided to monitor the plant stack emissions and waste water discharged from the site. Indication and recording of the corrected concentrations of gases in the stack shall include: A.
Flue gas O2
B.
Flue gas CO
C.
Flue gas SOX
D.
Flue gas NOx
E.
Flue gas opacity (dust)
F.
Flue gas temperature
G. Flue gas Flow H)
Flue gas H2O
Measuring points and all analyzers shall be subject to related law. The Bidder shall furnish all required standard gas for calibration during commissioning stage. Local analyzer cabinet shall be weatherproof and be complete with lightning protection and all necessary heaters, wiring, tubing, vents, and accessories. The shelters include air and humidity conditioner to protect cabinets from corrosion or deterioration All analyzer shall be of in-situ type. The NOx, SO2 analyzers shall be calibrated by optical filter or certified standard gas. The flue gas monitoring for continuous emission monitoring system shall be performance and accuracy tested by an institute approved by the administrator of environment Chlorine and halogen residuals shall also be monitored in the water sent to waste after treatment. Indication and recording of the signals on the waste water disposal channel shall include: A.
pH 8-34 KHABAT TPP UNITS 1&2 - VOLUME I
B.
COD
C.
SS
D.
Flow
The PH on pond, COD, and SS analyzer on the disposal channel shall be provided two isolated 4 ~ 20 mA DC signals for waste water treatment control system (PLC). The flow, temperature and pH levels of the wastewater shall be continuously monitored and displayed by the PLC. Alarm levels shall be presented to the operator for action. The instruments for stack and water discharges shall be complete and shall display the instantaneous value of the measurements to the operator in the CCR via the PCS. Local indication shall also be provided for each measurement at the respective measuring meter. Fault alarms for each instrument shall be raised in the CCR. The measurements shall be displayed by the instruments in a format suitable for submission to the appropriate environmental agency. The PCS shall display and record the measurements in the same way. All measurements shall be compensated, where necessary, for variations in temperature, atmospheric pressure, humidity etc and the correcting values made available for display by the PCS. The PCS shall be capable of performing hourly and daily averages for all measurements and give early warning alarms of measurements approaching their maximum limits. The equipment shall be of proven reliability and shall be subject to the approval of the KNOC. Details of other sites where the equipment has been installed shall be provided. LCD Operator stations in the related office shall monitor the status of the stack gas and waste water treatment system The Bidder shall submit a configuration diagram drawing and description of TMS on shown the measuring points.
8-35 KHABAT TPP UNITS 1&2 - VOLUME I
8.11
Station Clock System A station clock system shall be provided to synchronize the PCS, TCS, VMS, ECS, and other plant control systems, for the purposes of synchronizing data acquisition, data logging, alarm and trip events, etc, for all systems employed in such a manner on the site. The station clock will be set from an appropriate radio time signal (e.g. GPS signal). The system will be capable of monitoring the grid system time, and display to the operator in the CCR, the time difference and GMT. The equipment shall be supplied with sufficient outputs of the correct type to meet the operating requirements of the plant. Station clocks synchronized to the system, shall be supplied and installed in locations to be approved during the detailed design stage.
8.12
Load Dispatch A communications interface for the transfer of data to and from a Central Load Dispatch facility shall be provided within the PCS.
8.13
Fire Detection and Alarm System A comprehensive fire detection and alarm system shall be provided to cover all equipment on site that could constitute a fire risk. The system shall be designed and installed in accordance requirements of NFPA and shall in addition comply with any requirements of the relevant national authority. All necessary hardware, software, fire detectors, manual call points, local alarm panels, remote alarm panels, cabling, electronic sounders, beacons and interface to the PCS shall be provided. The following alarm facilities, including initiation devices, shall be provided: A.
both local and remote audible and visual indication of the operation of any water spray protection or foam protection system;
B.
both local and remote audible and visual indication of the operation of any building or plant area fire detection system;
C.
local and remote audible and visual indication of the operation of any manual break glass alarm switch;
8-36 KHABAT TPP UNITS 1&2 - VOLUME I
D.
Remote, audible and visual indication of status and fault condition of each fire pump.
Smoke detectors of the photoelectric type and heat detectors shall be suitably located to detect and provide early warning of fire risks. All detectors shall be suitable for the specific areas in which they are located and particular attention shall be paid to ensure that airborne dust does not affect the correct operation of the detection equipment. On detection of fire both visual and audible alarms shall be provided locally and remotely in the CCR. All detection circuits shall be monitored against open/short circuits. Should a malfunction occur in any circuit, this shall result in a fault condition on this detection zone, while all other zones shall continue to operate normally. Manually operated break glass alarm switches shall be provided for mounting at selected positions throughout the plant, and buildings. All call points shall be provided with a key test facility to allow for testing of the system without dismantling or breaking the glass. The fire fighting system shall be connected to the building services control system to shut down forced ventilation in the event of a fire. Where required, local alarm and indicator panels shall be provided and mounted in approved locations adjacent to the areas being protected. The remote alarms and indicators covering all sections of the plant, together with spare ways, shall be mounted on the main fire alarms panel in the main control room. 8.14
Gas Detection System The gas detection monitoring system shall be designed for automatic and continuous monitoring of combustible gases using catalytic combustion or infrared principles. The system shall be intrinsically safe and to approved international standards. Each gas detection loop shall generate alarms at the local cubicles and PCS for both the lower and upper explosive limits. The gas detection monitoring system shall be microprocessor based providing self-test and diagnostics facilities. A redundant serial communication link shall be provided to the PCS allowing display of gas concentrations, warnings, 8-37 KHABAT TPP UNITS 1&2 - VOLUME I
alarms and system fault conditions. Hardwired signals for tripping the plant on detection of high gas levels in the area shall be triplicated and configured to give a 2 out of 3 voting system. 8.15
Private Automatic Branch Exchange (PABX) The plant shall be constituted of: A.
Central unit PABX
B.
Connection with the public grid on some exchange lines (about 6)
C.
An adequate number of telephone positions, located in various places inside the plant
D.
An adequate number of telephone sets for the administration buildings (at least one per office)
E.
Telephonic cable net.
The number of telephone sets in the control room shall be 3 (three), enough for the plant operation even in emergency situations. The central unit shall include also battery charging sets and accumulators with a sufficient capacity to guarantee the continuity of the communication service also in emergency situations. An integrated services digital network (ISDN) type PABX, approved for connection to the public switched telephone network (PSTN) shall be provided for the power plant. The Bidder shall specify the initial installed capacity including numbers of exchange lines, tie lines and extension lines. A personal computer (PC) based telecommunication console shall be provided together with a VDU, keyboard and headset. The exchange shall be capable of future expansion. The Bidder shall specify the ultimate expansion capacity which shall be to approval. The interconnecting cable between the PABX and the PSTN shall be the responsibility of others but the Bidder shall provide all facilities for the connection of this service including ducting within the building where the telephone exchange is located. All other internal telephone connections within the power station boundary, including cabling to and within the administration, control and turbine area, etc, shall be the responsibility of the Bidder.
8-38 KHABAT TPP UNITS 1&2 - VOLUME I
The telephone system shall be powered via a battery/charger system to maintain the PABX and the PA system in normal operation for a period of not less than 10 hours in the event of a failure of battery charging current, when the exchange has been fully extended. The batteries shall normally be kept charged by a dual battery charger unit, each charger comprising a float charger with manual boost charge facilities with capacity sufficient to cater for ultimate extension facility referred to previously. Each battery charger shall be housed in a separate robust and well constructed cubicle with good access to all components and equipment. It shall not be possible for the load to become disconnected from both batteries and chargers simultaneously. The PABX system shall incorporate a self-surveillance facility for monitoring the status of the PABX equipment and appropriate alarms shall be raised automatically to alert the operator when a fault is detected in the system. Telephone instruments shall be provided for all equipped circuits. These instruments shall be provided to suit the use and location and shall include basic wall and desk mounted units, executive handsets (with secretary and hands free facilities), background noise suppressed units with acoustic hoods for noisy plant areas and weatherproof units for external areas. 8.16
Public Address System (PA) A PA system shall be provided for the broadcast of announcements throughout the station. Loudspeakers shall be connected on a zonal basis with the call station and zone selection facilities located in the CCR. The sound output level of the PA system shall be designed to achieve a sound pressure level 10 dB higher than the ambient noise in the area to ensure speech intelligibility. Loudspeakers shall be supplied suitable for the environmental conditions and be positioned and oriented to give the required sound coverage. The PA system shall incorporate a self-surveillance facility for monitoring the status of the PA equipment including loudspeakers. Appropriate alarms shall be raised automatically to alert the operator when a fault is detected in the system.
8-39 KHABAT TPP UNITS 1&2 - VOLUME I
8.17
Closed Circuit Television, Intruder Detection and Site Access Control Systems A closed circuit television (CCTV) system shall be provided for the surveillance of the perimeter fence and gates. Fixed position cameras with fixed focal length lenses and pan-tilt-zoom (PTZ) cameras shall be employed to give the necessary coverage. The camera systems shall be digital based systems which shall be user configurable, scaleable, utilize digital storage devices and be implemented via large area networks. The Bidder shall be responsible for the design and positioning of CCTV cameras at strategic locations, mounted on buildings or using masts as required, to achieve the full coverage of the perimeter fence and gates. The CCTV system shall be designed to allow persons to be clearly seen at any position within the area of coverage. The CCTV images displayed on the monitors shall be of adequate clarity that will provide clear and unambiguous identification of persons or motor vehicles. Solid state CCTV cameras utilizing charge coupled devices (CCD) capable of providing high definition color video images shall be provided. Cameras installed in areas which are likely to be subject to changing light levels shall have lenses equipped with auto iris control facilities. Infra-red lighting shall be provided for cameras where the level of illumination during the hours of darkness is insufficient to give a clear image. The beam width of the lighting shall be matched to the focal length and coverage of the camera. Infra-red lighting shall be switched automatically by photo-cells during the hours of darkness. A digital storage system shall be provided capable of storing the CCTV images in time lapse or in real time modes as required. The images shall normally be stored in time lapse mode. The storage system shall have facilities to superimpose camera number and date/time data on the images. A sufficient number of color TV monitors shall be capable of displaying the image from any of the cameras on the system. The quantity of monitors shall be to approval. The monitors will be located in the CCR and the Gate House.
8-40 KHABAT TPP UNITS 1&2 - VOLUME I
An intruder detection system shall be supplied as part of the Contract. When an alarm condition is initiated, the security lighting in the zone and adjacent zones shall be switched on and images from the cameras in the zone and adjacent zones shall be displayed and recorded automatically. The intruder detection system shall alert security staff that an attempt has been made to enters the station via the security fence. Facilities shall be provided to manually control the security lighting. A site access control system shall be provided that covers all site access points. The site access control system shall consist of motorized gates, intercom between gates and CCR/gatehouse and facilities to operate gates form the CCR and gatehouse. CCTV cameras shall be located at all access points to provide clear identification of people and motor vehicles. Full details of the proposed intruder detection system, CCTV and access control system shall be provided with the bid submission. 8.18
Furnace Flame Viewing Television System A.
The CCTV cameras shall be equipped with weather and dust proof housing suitable for outdoor operation. Two(2) sets(per one unit) of furnace flame viewing CCTV cameras with automatic focusing and automatic light level adjustment shall be provided. The camera shall be furnished with suitable protection, cooling and purging mechanisms to be operated at the high temperature and the harsh conditions of the furnace. All required cooling and purging accessories shall be provided.
B.
The cameras shall be equipped with automatic retracting devices at the failure of power and cooling system. The cameras shall be automatically retracted to the safe position at the power failure and cooling system failure conditions.
Alarms at the high temperature and system failed
conditions shall be made and connected to the PCS. C.
Any camera located in outdoors shall be provided with the necessary weather
D.
protection equipment.
The electro-pneumatically controlled furnace color cameras shall be inserted
by operator in local and remote area(main control room) and
shall be retracted
to the safe position automatically at the loss of
coolant, camera temperature
high and power failure. Each camera
housing shall be connected to furnished instrument air to protect the 8-41 KHABAT TPP UNITS 1&2 - VOLUME I
lenses from moisture, soot and coal at the front lens of the probe at the same time. E.
The furnace cameras shall be equipped with automatic focusing feature and automatic light level adjustment.
F.
Camera assembly and control system, that is, CCD camera, monitor, camera housing,
retraction device, control unit, cooling/purging units
and accessories, etc. G. The furnace camera shall be operated by zoom lens with 4-20mA signal and it 8.19
shall be possible to zoom out and in to monitor the furnace flame.
Boiler Tube Leak Detection System The Bidder shall provide the boiler tube leak detection system of a wall welded contact type. Complete system including twenty(20) sensors, electronic cubicle, workstation, monitor(min. 21 inch) and printer shall be provided. Boiler tube leak detection system shall be interfaced with PCS for the monitoring and alarm in CCR.
8.20
Furnace Temperature Monitoring System The Bidder shall provide the furnace temperature monitoring system with laser type. Complete system including fifteen(15) pairs of laser sensors, electronic cubicle, workstation, monitor(min. 21 inch) and printer shall be provided. Furnace temperature monitoring system shall have capability of making thermography for thermal distribution of combustion zone and be interfaced with PCS for the temperature monitoring in CCR.
8.21
Weather Station Weather instrumentation shall be installed to provide the PCS with the following signals: A.
Ambient air temperature.
B.
Atmospheric humidity.
C.
Atmospheric pressure.
D.
Wind speed.
E.
Wind direction
The weather station shall be provided with all necessary housing and auxiliary 8-42 KHABAT TPP UNITS 1&2 - VOLUME I
equipment and shall be suitable to withstand the full range of climatic conditions arising at the site. The weather station equipment shall be located in an open area away from any structures that may affect measurement accuracy. The data acquisition system shall contain any signal conditioning units necessary to interface with field instruments and also data processing storage functions 8.22
General Requirements
8.22.1
Introduction The following section describes the general requirements for the design, supply and installation of the control and instrumentation (C&I) systems for the plant.
All C&I equipment necessary to allow the safe, reliable and efficient
operation of the plant shall be supplied. 8.22.2
General requirement for instrumentation A.
Pressure gauge, switch and transmitter which are used to a corrosive or solid containing or solidifying fluid shall be provided with a diaphragm seal or seal pot filled glycerine or ethylene glycol.
B.
Diaphragm seals and seal pots shall be provided with a clean out connection.
C.
Dampener, capillary tubes and/or syphons, where required, shall be furnished.
D.
Five(5) way manifold valve for pressure differential instruments shall be supplied.
E.
Temperature transmitters shall be of smart type with HART protocol, compact
two
wire
temperature
transmitters,
offering
ultra
high
performance, together with linearization of 4∼20mA output and have the function of input/output isolation. They shall be calibrated by configuration hardware. Configuration hardware shall be provided by the Supplier. Temperature transmitters shall be provided with reference (cold) junction temperature compensation circuits. F.
Thermocouple shall have dual elements with spares connected to terminals in the connection head.
8.22.3
Environmental requirements In general, equipment supplied shall conform to the environmental classes 8-43 KHABAT TPP UNITS 1&2 - VOLUME I
defined in the relevant international code & standard. The internal air in an equipment cubicle will, at least in some parts, be higher than the defined ambient temperature. For design purposes the internal air shall be taken as 15°C higher than defined maximum ambient given in the relevant international code & standard In operation, during installation and maintenance, and during transit, the equipment may be subjected to continuous vibration and shock loads. The mechanical design shall take account of these conditions to minimize the risk of failure. Instruments shall be mounted in heated or protected locations wherever possible in order to minimize the effects of ambient weather conditions. All field mounted instruments will be weatherproof to IP65 or equivalent and suitable for the local operating conditions. Field mounted instruments shall be provided with a suitable sun-shade to protect them from direct sunlight. All instruments, instrument tapping points and controls shall be accessible from floor level or permanent platforms. The design and construction of cubicles, cabinets and panels shall be such that they meet the minimum requirements of being dustproof, protected against dripping water when tilted at 15 degree and vermin proof. For equipment located outside or in harsh environments then the protection rating shall be suitable for the duty and shall be subject to approval. Instruments in water services or where water can accumulate in the impulse lines shall be trace heated where the ambient temperature can fall below 0°C. Wind chill factor shall be considered. 8.22.4
Hazardous areas All C&I equipment shall be suitable for the specific area in which it is located. If equipment is expected to operate in the presence of flammable or explosive materials either explosion proof construction or the use of barriers to obtain intrinsic safety will be acceptable. All equipment offered for use in such areas shall have the necessary certification by the appropriate Certification Bureau and its proposed application shall fully comply with all conditions of the 8-44 KHABAT TPP UNITS 1&2 - VOLUME I
certificate. The design and installation of the equipment shall take into account fully the appropriate sections and requirements of the relevant international code & standard. 8.22.5
Insulation and isolation All circuits intended to be electrically isolated from external circuits shall be designed to withstand the following voltage levels: A.
All circuits requiring isolation (including contacts of switches, relays or contactors) shall have an insulation resistance across the isolating barrier of not less than 20 Mega ohms when measured at 500 V dc.
B.
A circuit intended for connection to 110 V ac or 125 V dc and above shall withstand 2 kV 50 Hz rms between itself and all other points for one minute.
Connections to the external power sources shall normally be made via switches and fuses or via miniature circuit breakers. 8.22.6
Electromagnetic compatibility (EMC) No equipment provided under the contract shall generate electrical or electromagnetic interference at a level detrimental to the performance of other equipment or to a hazard or of discomfort to personnel. The equipment shall meet the requirements of the relevant international code & standard
8.22.7
Identification Each item of equipment shall be durably and legibly labelled, indicating the purpose, plant identification number and where necessary any operating position functions. Labels shall be provided on front and rear access doors of all cubicles. Labels shall also be provided inside cubicles to assist the identification of apparatus and terminals. Instruments, valves, actuators and all other field-mounted equipment shall similarly be identified with suitable labels. The material of all labels and the dimensions, legend and method of printing shall be to approval. Surfaces of labels for cubicles and control equipment shall have a matt or satin finish to avoid dazzle. Colours shall be permanent and free from fading. Danger labels shall have red lettering on a white 8-45 KHABAT TPP UNITS 1&2 - VOLUME I
background. 8.22.8
Installation All instrumentation shall be installed in compliance with the relevant international code & standard and the recommendations of the manufacturer. Only one instrument shall be fitted to each tapping point. Separate instruments shall be provided for control/indication and protection systems. Connections to instruments after the primary isolating valve shall be made using steel or a material corresponding to the piping class of the line to which it is connected. Instrument process tubing systems are defined as all the valves, fittings, tubing, supports, expansion loops, and piping used to connect instruments to the main process piping downstream of the first/second root valve to other instruments or apparatus including volume chambers, or measuring equipment. This shall include test, purge, vent and drain connections. To insure flexibility, connections at instruments shall be made with tubing bent through an arc of not less than 3-times the radius with at least 1 inch of straight tubing run beyond the last point of attachment to the structure. Stainless steel (316) shall be used to prevent erosion or corrosion problems. Instrument isolating valves, vent/test valves and instrument manifolds shall be provided for all devices where appropriate. Instrument vent and drain points shall be routed to a safe position away from site personnel. The Bidder shall provide the instrument cabinets and/or stands to mount transmitters and other local instrument.
The cabinets for outdoor service
shall be enclosed type and shall be insulated suitable way to protect the instruments from condensation and freezing. The cabinet for indoor service shall have a top plate covering the entire cabinet to protect the instruments from drips. A single instrument (transmitter) shall be located using galvanized floor mount. For outdoor service, the Bidder shall use the instrument rack or housing for both transmitters and other local instrumentation. All indicating instruments and controls shall be readable and accessible from floor level or permanent platforms. Local gauge glasses shall be visible from 8-46 KHABAT TPP UNITS 1&2 - VOLUME I
any control valve that controls the vessel level. Instrument ranges shall be such that normal working indication lies between 60 and 75 per cent of the span. Post or bracket mounts for instruments shall not be attached to pipe work, removable flooring, and handrails or be directly affixed to machinery and equipment subject to vibration. 8.22.9
Flow measurements Flow measurement devices operating on differential pressure principles shall be designed in accordance with the requirements of the relevant international code & standard. For high pressure applications, the carrier for the primary device shall be of similar material to the pipeline in which it is to be mounted, and shall be connected into the pipeline by butt-welding. Other applications shall use flanged connections wherever possible. For line sizes below 50 mm, a precision pipe assembly shall be utilized with a minimum line size of 50 mm. All differential pressure devices shall be provided complete with tapping point isolation valves, 3-valve manifolds and drain valves or 5-valve manifolds, as required. Positive displacement flowmeters shall be used for custody transfer flow measurements. The flowmeters shall in all cases be suitable for the process conditions applicable to the measurement location and the environment in which it is mounted. Meters used for energy, tariff or metering purposes shall be supplied, complete with adjacent pipe sections, where necessary, with calibration certification from an approved laboratory. Displacement flowmeters shall be capable of accuracies to within ±0.25 percent. Where density, temperature or pressure corrections to tariff metered performance monitoring signals are required, then such measurements shall be made close to the flowmeter location. Flowmeters employing alternative measurement principles may be utilized for appropriate applications subject to the approval of the KNOC. Flow element shall be selected within the following types
8-47 KHABAT TPP UNITS 1&2 - VOLUME I
a.
Flow nozzle type : For high pressure large flow accuracy within ±1.0% of span
b.
Flow orifice type : Replaceable type, accuracy within ±1.0% of span
c.
Positive displacement type : For oil, water flow, accuracy within ±0.25 % of full scale
d.
Area meter type : For oil flow, accuracy within ±1.0% of span
e.
Pitot tube type : For steam or water flow, accuracy within ±1.0% of span
f.
Cone type :For steam, water, air flow, accuracy within +0.5% of span
g.
Fechheimer pitot tube type: for air, gas duct
8.22.10 Level measurements Level measuring devices may be of the direct measurement, differential pressure or electrical/electronic type as appropriate to the application. For local indication of level, direct measuring devices shall be used. Level measuring equipment shall be capable of being removed without the vessel or other instruments being taken out of service. Level gauges shall be of the reflex type made from stainless steel bar and fitted with toughened borosilicate glass and marked with their safe working pressure and temperature, except on low temperature and pressure application when transparent types may be used. Gauge glasses for boiler applications shall be in accordance with the relevant international code & standard. Each gauge shall be fitted with top and bottom isolation valves with full bore drain valve at the bottom and plugged vent at the top. Condensing chambers shall be used on the top connections of all steam/water level systems. They shall be correctly sized, positioned safely and the whole installation shall be to approval.
Gauges shall be arranged so that the
visible length is in excess of the maximum operating range. Differential pressure transmitting devices shall preferably be used on all services other than slurry. Displacement type instruments and switches shall be mounted in external cages with flanged connections rated the same as the vessel. This type of instrument shall not be used for applications involving viscous, corrosive or flashing liquids. 8-48 KHABAT TPP UNITS 1&2 - VOLUME I
Direct measurement of level by means of internally mounted floats etc., shall only be used when the switch point is either well defined in advance or if it is adjustable in service, if the vessel can be emptied and/or depressurized for the removal of the switch without affecting the normal operation of the plant, or where choking of extended connections is likely to occur. Float switches shall be glandless with magnetic coupling. 8.22.11 Pressure measurements In general, local pressure gauges shall operate on Bourdon tube principles and shall comply with the relevant international code & standard. Low pressure gauges may employ manometer or barometer devices to indicate small gauge, differential pressures or vacuums. Sensing element materials shall be selected to resist corrosion by the process medium. When gauges or transmitters are to be used for duties where the process medium temperature exceeds 70°C, siphon loops shall be utilized. Gauges measuring low ranges that can be exceeded by a higher containment pressure shall be fitted with over-range protection. Gauges shall be fitted with vent/test valves. Blow-out devices shall be provided for high pressure applications. Pressure switches shall only be provided with the approval of the KNOC. If used, pressure switches shall be such that under normal process operating conditions the contact in the switch shall be closed unless otherwise approved by the KNOC. 8.22.12 Temperature measurements The method of temperature measurement to be employed shall be selected for the particular application bearing in mind requirements for accuracy and reliability. Sensing elements for air, inert gas and radiant temperature measurements shall be complete with suitable protective sheath. For steam, water and hazardous applications, thermowells shall be utilized.
8-49 KHABAT TPP UNITS 1&2 - VOLUME I
Resistance thermometer detectors (RTDs) shall be used only where they can be readily replaced without loss of plant capability. RTDs shall be to the relevant international code & standard using 3-wire connections for applications up to 450°C. On differential temperature measurements RTDs to the relevant international code & standard will be used. Thermocouples shall be used in accordance with the requirements of the relevant international code & standard. Careful consideration shall be given to the design and installation of thermocouple systems to ensure that inaccuracies are not introduced into the measurement due to the use of unsuitable materials or by incorrect installation.
Cold junction compensation
shall be provided as well as compensating cables of suitable size and material where required. Thermocouples shall be installed in such a way as to be capable of replacement with the plant in operation. Local temperature indicators shall be supplied with a thermowell and shall preferably be of the bimetallic type and of the multi-angle variety. No temperature measuring system shall use mercury as its sensing medium. Temperature transmitters shall be provided for RTDs and thermocouples. 8.22.13 Position measurements Position measuring devices or switches (e.g. limit switches, proximity switches etc) shall be remote from sources of heating or leakage of process, gases or liquids. Where vibration-free locations are not possible, the mounting arrangement shall incorporate flexibility in the coupling between the device and the point of measurement and the transducer mountings. For position instruments in high temperature applications the calibration of position transducers and the setting of limit switches shall be unaffected by the hot/cold operating temperatures of start-up and shutdown. 8.22.14 Quality measurements Quality measuring instruments monitoring chemical or physical properties of process fluids and substances may be installed either directly in the process line or vessel or via a sampling system. Sensors shall be of rugged 8-50 KHABAT TPP UNITS 1&2 - VOLUME I
construction and shall not require frequent maintenance or recalibration. Where sensors require the use of calibration solutions or gases, then a minimum of one year’s supply at normal usage shall be supplied. Where sensors require replacement or removal for re-calibration or rejuvenation at regular intervals, then an adequate number of spare sensors shall be supplied for one year’s normal usage. The water analysis system shall monitor the quality of the process water and steam at various points, to alarm the abnormal conditions, to record the conditions and to provide signals for controlling the chemical injections to the condensate water and boiler feedwater. The sample conditioning rack, analyzer panel and control cabinet shall be installed in the local area. Each analyzer shall have a self-contained digital readout meter. Each analyzer shall provide a high or high/low alarm status. The alarm points shall be set and indicated from the monitor's readout meter. Each analyzer shall have one(1) analog output circuits with independent zero and span adjustments. However, if a signal is required for chemical feed control system, the Bidder shall additionally one(1) analog output. The sample conditioning systems shall maintain samples within the following tolerances of the desired values using cooling water at 35 deg.C maximum and approximately 5.9 kg/cm2g operating, 10 kg/cm2g maximum. Sample flow to each cell or analyzer ± 2 percent. Sample temperature to each cell or analyzer 25 ± 1 deg.C. Analyzer shall be following types a.
Condenser Hotwell
: CC
b.
Codensate Pump Discharge : pH, SC/CC, DO, Sodium
c.
Deaerator Inlet
: CC, Hydrazine
d.
Economizer Inlet
: Sodium, SC/CC, pH, DO, Hydrazine, Silica
e.
Drum Water Outlet
: Silica, Ph, SC/CC
f.
Drum Steam Outlet
: CC
g.
Main Steam
: CC, Silica
h.
CCW pump discharge
: grab sample
Analyzer signals shall be provided to give remote indications of the quality 8-51 KHABAT TPP UNITS 1&2 - VOLUME I
measurements at the PCS. 8.22.15 Vibration measurements A.
The Bidder shall provide a complete set of vibration probes, vibration monitoring and analyzing system(VMS)
These system shall be installed
in the electronic room and computer room located in main control building. B.
The vibration monitoring and analyzing system shall be capable of on-line computerized monitoring and analyzing for steady state and transient machinery operating conditions including startup and shutdown as well as normal operation.
C.
The vibration monitoring and analyzing system shall comply with API670 4th Edition.
D.
The vibration measuring points shall be on the turbine-generator, all major rotating and reciprocating equipment having M.V motor.
E.
Vibration measuring devices shall be of the non-contacting transducer type and shall be designed and selected for operation in their particular intended environment. Vibration transducers shall be located at or adjacent to each machine bearing mounted in tapped holes in the bearing housing or by rigid bracket. For the measurement of both relative and absolute shaft vibration two transducers shall be used radially mounted in the same transverse plane perpendicular to the shaft axis and 90° apart.
F.
Relative vibration shall be measured by the use of non-contacting transducers (proximity type) to measure the relative motion between the shaft and bearing housing.
G. Absolute vibration shall be measured by non-contacting transducers, measuring relative shaft vibration, in combination with seismic transducer (velocity type or accelerometer), measuring the support vibration. Both transducers shall be mounted close together so that they undergo the same absolute motion in the direction of measurement. Their conditioned outputs shall to be vectorially summed to provide a measurement of the absolute shaft motion. H.
The measurement of both relative and absolute shaft vibration shall be broad band so that the frequency spectrum of the machine is adequately covered.
8-52 KHABAT TPP UNITS 1&2 - VOLUME I
I.
The vibration monitoring system shall consist of a rack chassis, redundant power supplies, interface module, monitor modules, relay modules, and communication interface devices.
J.
The monitoring system shall be microprocessor based with extensive selfdiagnostic facility, which will include the monitor as well as the transducer and continuity of cables. The system shall display operating status for each channel and value indication display with measuring unit at the each cabinet front. The CPU card shall be able to report all alarm event and system event to the analyzing computer.
K.
One(1) vibration analyzing computer per Unit, based on any standard Windows, shall be supplied for analyzing and displaying the vibration.
L.
The hardware requirement for vibration analyzing system per Unit shall include one(1) 21" LCD monitor with keyboard, hard disk, CD-ROM, backup drive, one(1) laser color printer, network card, and modem, etc.
M. The function such as bar graph, trend, orbit/time base, spectrum, polar, cascade, bode plot, X vs.Y, Waterfall/Full Waterfall, Shaft Centerline, Acceptance Region etc. shall be provided, and gather startup, shutdown data in wave form and spectrum sample. N.
The vibration analyzing computer shall provide an interface module to receive the required plant system's signals for the automatic diagnosis of machine problems from the PCS.
O. The Vibration analyzing system shall be so designed to allow time synchronizing by the plant master clock in the system. P.
The Bidder shall submit the VMS configuration drawing.
8.22.16 Control valves and actuators The valves shall not create a sound pressure level, as defined by OSHA standards, greater than 85 dBA without using insulation material and noise attenuation devices such as baffle, silencer, and diffuser under specified operating conditions. The Bidder shall show on the data sheet predicted sound levels. Control valves shall be designed to give positive control, and free from cavitation over the entire load range. All materials used must meet applicable codes and standards. Valves welded in piping shall be of a design to permit removal of plugs and seats without removing the control valve from the line. Steel valves shall accord to ASME B16.34 8-53 KHABAT TPP UNITS 1&2 - VOLUME I
The maximum seat leakage shall meet the requirements of ANSI/FCI 70.2 as applicable for the intended use. The valve trim parts must be of quick change type. No trim component including the seat ring shall be welded or screwed into the valve body or bonnet. Control valves shall be supplied with suitable actuators matched to the operational and environmental requirements of the plant. All actuators shall be provided with a means of local control which shall be capable of being utilized without the use of tools. Loss of remote/automatic operation of an actuated valve shall be alarmed to the operator. All control valves shall have local and remote indication to show the actual position of the valve. For remote control or indication purposes a suitable position transmitter shall be provided (e.g. based on a linear variable differential transducer). Where it is only necessary to provide a limited number of discrete position indications, then position actuated switches shall be used. Switch settings shall be adjustable. Smart positioners shall be of microprocessor based with HART protocol. It shall be two-wire, 4~20mA DC loop powered by PCS. Seat leakage class for the following control valves as minimum shall be V in accordance with ANSI/FCI 70.2. a. Boiler drain valves b. Turbine drain valves c. Bypass valves d. BFP minimum flow control valves e. HP heater emergency drain control valves f.
Condenser makeup control valves
g. Etc 8.22.17 Motorized valves Motorized valves shall be used for isolation purposes and shall consist of selfcontained actuator units with motor, gearbox, contactor, controls, limit/torque switches and all auxiliary equipment installed in each actuator housing. A 8-54 KHABAT TPP UNITS 1&2 - VOLUME I
lockable local/remote selector switch with open/close controls shall be located on the actuator. The actuator shall be designed such that it may be disengaged from the valve if a fault has occurred and the valve operated normally by using the hand wheel. Each end of the actuator travel shall be fitted with suitable limit and torque switches for preventing overtravel and consequential damage to the actuator. Limit switches shall be installed also to provide remote indication of the valve position. Local valve position indication shall be provided on the actuator. 8.22.18 Solenoid valve Solenoid valves shall be of adequate size to insure proper operation. Solenoid valves shall have soft seats to insure tight shut off. Material shall be suitable for service fluid. Solenoids shall have sufficient thermal capacity for continuous energization. Solenoid valves shall be yoke or diaphragm mounted complete with interconnecting brass pipe or copper tubing between the solenoid valve, diaphragm and positioner. Solenoid coil insulation shall be Class H or suitable for environmental conditions. 8.22.19 Manual valves Manual valves important to the process shall have their open/closed status monitored and displayed. In such cases limit switches shall be provided at each end of travel. 8.22.20 Pneumatic actuators/positioners Pneumatic actuators/positioners shall be supplied suitably matched to the operational and environmental requirements of the valve or driven unit. Pneumatic actuators/positioners shall cause the valve or driven unit to operate over its full stroke, from a 0.2 to 1 bar signal by means of any of the following: A.
pneumatic signal direct to the actuator;
B.
pneumatic signal to a positioner;
C.
electrical signal to electro/pneumatic converter;
D.
electrical signal to solenoid pilot valve.
Pneumatic actuators and drive units shall automatically return to a safe/predetermined position upon signal and/or air supply failure unless the process 8-55 KHABAT TPP UNITS 1&2 - VOLUME I
operating requirements or the Specification dictate a “stay put” response. “Lock up” devices shall be provided where necessary to ensure the actuator remains in the operating position prevailing immediately before an air failure. Volume boosters shall be provided on loops where fast-response is required (eg pressure) to enhance stability. All positioners and electro/pneumatic converters shall be furnished with three pressure gauges, air supply, signal input and control air output, and an air filter regulator set with a lubricator. Position transducers and limit switches shall be provided to give remote indications of the valve positions at the PCS. 8.22.21 Cubicles and racks Unless otherwise stated all equipment shall be accommodated in suitable cubicles or racks. Cubicles, cabinets, racks and control panels shall all conform to applicable IEC 60297 standards. The general design of racks and cubicles shall be subject to approval. They shall be free standing, fabricated steel construction and shall not exceed 2300 mm in height. The lowest mounting point, plug-in group or terminal block shall be not less than 400 mm above floor level. The methods used for cubicle mounting, including the provision of anti-vibration mounts, shall be to approval. The welding of cubicles, cabinets, racks and panels to support steelwork is prohibited. Internal lighting and maintenance power sockets shall be provided within the cubicles. All enclosures containing electrical equipment shall be provided with thermostatically controlled anti-condensation heaters. Cubicle doors shall be provided and arranged to lie flat back when open so as not restrict access to the cubicle. The doors shall be of the lift-off type secured with 3-point locking system. Cubicles and doors shall be structurally stiff and braced to withstand twisting without distortion flush fitting and sealed with a gasket of rubber or other approved material to prevent the ingress of dust and vermin. Cubicles and racks shall be complete with all necessary terminal blocks, cable 8-56 KHABAT TPP UNITS 1&2 - VOLUME I
glands, gland plates and earth bar with earthing connection. These items shall be located in an approved, easily accessible, position and so arranged that the terminals face the access direction for convenience during maintenance. The design shall be suitable for either top or bottom cable entry for all cables. The gland plates shall be removable and in the case of floor mounted bottom entry cubicles, shall be not less than 200 mm above the base of the cubicle to allow access for applying the cable gland. Where cable glands are not used then provision must be made to seal the cable entry to ensure that the cubicle is dust proof, vermin proof and has a suitable fire rating. In addition provision for adequate cable support within the cubicle must be made. Forced ventilation shall not be used without the approval of the KNOC. Where forced ventilation is approved, fans shall be duplicated to provide 100 per cent standby capacity and shall initiate remote alarms in the event of failure. Ventilation systems shall comply with noise limitations imposed by the international standards. Replaceable dust filters shall be provided. Terminal boards shall include 20 per cent spare terminals after all external cables have been terminated including the screens and spare cores. All C&I cubicle wiring shall consist of copper wires of not less than 1 mm2 cross-section except for wiring associated with switchgear control and protection and CT and VT secondary circuits which shall not be less than 2.5 mm2. 8.22.22 Testing The Bidder shall carry out the following tests on the completed equipment in the Manufacturer’s works.
The KNOC reserves the right to witness such
tests. A.
visual inspection
B.
functional tests
C.
redundancy checks
D.
control loop testing
E.
voltage withstand test and insulation test
F.
full demonstration of the applications software.
8-57 KHABAT TPP UNITS 1&2 - VOLUME I
Where a number of items of equipment are intended to operate together, the complete assembly shall be tested to demonstrate that the interconnected items are compatible. Site acceptance tests shall include, but not be limited to, the following: G. demonstration of the correct functioning of hardware and software H.
redundancy tests
I.
data communications checks
J.
commissioning tests including instrument calibration checks, loop tests,sequence, control and protection calibration and logic tests, demonstration of operator displays, alarm facilities and other functional software packages (eg sequence of events, data historian, performance monitoring, etc).
8.22.23 Documentation All documentation shall be in the English language with all units expressed in SI quantities. The following documentation shall be supplied during the design phase of the Contract to a schedule agreed within 1 month of Contract award: A.
design and operation philosophy documents
B.
functional design specification
C.
graphics functional design specification
D.
alarm philosophy document
E.
technical descriptions and data sheets
F.
hazardous area data
G. instrument data sheets H.
cable schedule
I.
instrument schedule
J.
alarm schedule
K.
input/output schedule (including serial data)
L.
general arrangement drawings
M. equipment layout drawings 8-58 KHABAT TPP UNITS 1&2 - VOLUME I
N.
installation drawings
O. process flow drawings P.
piping and instrumentation diagrams
Q. single line diagrams R.
wiring diagrams and schematics
S.
cable connection/termination drawings
T.
interface diagrams
U.
software listings
V.
commissioning procedures
W. functional test procedures X.
performance test procedures
Y.
hardware test specification
Z.
software test specification
AA. factory acceptance test procedures BB. special tools CC. spares - commissioning and operating. In addition to the general requirements for operating and maintenance instructions detailed elsewhere in the specification the following specific requirements for computer-based systems shall be provided. Operator assistance documentation comprising: DD. operation and control philosophy EE. menu guide to control system facilities FF. description of all sequences in a structured step-by-step format GG. printed error message guide HH. alarm message guide II.
brief description of any hardware back-up features
JJ. process parameter values under normal operating regimes KK. hardware troubleshooting guide LL. instructions for changeover from remote to local control and vice versa MM. plant configuration and database listing NN. plant operating system listing OO. user-configurable software listing PP. system error messages listing 8-59 KHABAT TPP UNITS 1&2 - VOLUME I
QQ. troubleshooting guidelines RR. on and off-line diagnostic software SS. communications network management software TT. hardware list and system diagrams UU. start-up instructions for all hardware VV. listing of system error messages WW.
description of links or interface hardware between vendor control
packages and the Plant Control System XX. I/O card listing identifying location and function.
8.22.24 Support tools and calibration equipment The Bidder shall provide all necessary special tools, calibrations, programming, recording and fast trending recording equipment necessary for the maintenance and support of the C&I systems specified in this specification. The Bidder shall supply a list of all items with his tender. 8.22.25 Spare parts The manufacturer should recommend his list of spares and the level of holding for each section of the control and instrumentation proposed for the plant. This shall include commissioning spares and those required to support the plant for 2 years operation. 8.22.26 Instrument and electrical test equipment The Bidder shall provide one(1) lot of instrument and electrical test equipment for two(2) Units.
8-60 KHABAT TPP UNITS 1&2 - VOLUME I
9
CIVIL WORKS
9.1
General Requirements for Civil Works
9.1.1
General This section of the specification covers the civil engineering and building works (collectively referred to as the “civil works”) required for the construction of the Khabat thermal power plant units 1&2 in the Kurdistan Region. The civil works forms parts of
design and build project provided by the Bidder under a
turnkey contract and shall include any preliminary studies, fully detailed design and construction of all civil works, auxiliary works and services including building services systems necessary for the completion of the steam generated power plant. The civil works required shall include, inter alia, supplementary site investigations and data collection as deemed necessary by the Bidder, detailed design, preparation of construction drawings, procurement of materials, execution and maintenance of works complete in all respects, provision of record drawings, CAD diskettes and microfilms as described herein. The Bidder’s attention is brought to the existing site layout and existing site services drawings which may or may not be available. If available, they are included in the documentation. The necessary removal and/or diversion of these services shall be deemed to be included in the Bidder’s scope of works and the Bidder is required to fully allow for these works in his offer. 9.1.2
Civil programme and method statements A detailed civil design and construction program shall be submitted in accordance with the Conditions of Contract and as specified in other sections of this Specification. The Bidder shall prepare comprehensive method statements for all major construction activities and submit these to the KNOC for review at least thirty (30) days prior to the commencement of the relevant activity.
The method
9-1 KHABAT TPP UNITS 1&2 - VOLUME I
statements will include, but not be limited to, working methods, construction plant utilization, temporary works, construction sequence, security and safety arrangements. 9.1.3
Planning and building permits/approvals The Bidder shall ensure timely submission of all necessary details to the Local Municipality and others for items relating to these conditions. The Bidder shall be responsible for obtaining all building permits. Any application shall be made by the Bidder, and allowance for all costs related thereto shall be deemed to be included in the Contract. The Bidder shall be responsible for preparing and issuing all necessary documents
required
for
obtaining
the
above
mentioned
building
permits/approvals. The Bidder shall make allowance for the above procedures in his program for the Works. 9.1.4
Site investigations Any site survey, geotechnical and other subsurface information, hydrological and meteorological data if provided with this document for “Information Purposes”, shall not relieve the Bidder’s responsibility for fully assessing for himself surface and sub-surface ground conditions and buried constructions and obstructions. The Bidder shall be fully responsible for arranging his own site
survey,
estuarine
studies,
bathymetric
survey,
geotechnical,
contamination and hydrological investigations which are necessary to fully assess surface and sub-surface conditions on site and to determine any necessary meteorological data prior to designing the works. The escalation of construction cost due to Bidder’s design changes that may be occurred by deviation between site investigation data and the actual site conditions can not be accepted at any case. Any further onshore geotechnical investigation and offshore study/survey shall be carried out by an approved independent subbidder specializing in soil mechanics and foundation engineering at the Bidders expense. 9-2 KHABAT TPP UNITS 1&2 - VOLUME I
All site investigations shall comply with ASTM D 2113 and ASTM D 5922 or the related ASTM Standards. All geotechnical and laboratory testing shall be conducted in a NAMAS accredited laboratory or similar approved. The Bidder’s scope of works, method statement and standards used in carrying out the site survey and geotechnical investigation, borehole layout, etc., shall be submitted to the KNOC as a Design Intent Memorandum (DIM) for approval not less than 4 weeks before the site investigation work commences. The Bidder shall submit to the KNOC all reports on the geotechnical and offshore investigation as the work proceeds, followed by a Final Report for the KNOC’s approval, containing complete borehole logs, results of in situ and laboratory testing and his DIM with respect to the philosophy for foundation designs, heat recirculation studies with verification and justification of the chosen designs. The cost of all Site survey, offshore, geotechnical, contamination, hydrological and meteorological investigation works shall be deemed to be included in the Contract Price. The Bidder shall submit with his bid details of any further site investigation works he proposes to carry out prior to and during the construction of the works. 9.1.5
Ground contamination The results of any contamination survey carried out by the Bidder shall be advised to the KNOC. The Bidder, the KNOC shall agree on the necessary remedial measures.
9.1.6
Design and construction The Bidder shall make sufficient provision both in his program and the Contract to cater for: A.
The discovery of, and remedial treatment or removal as the case may be of any underground foundation constructions and buried services, including artificial obstructions. The Bidder shall take into consideration the history and past uses of the site. 9-3 KHABAT TPP UNITS 1&2 - VOLUME I
B.
The discovery of, and remedial treatment or removal to a licensed repository of any contaminated material.
C.
The discovery of, and remedial treatment of any unknown underground services. The Bidder’s attention is drawn to the information shown on existing drawings which may be available and included with the document.
D.
The discovery of, and remedial treatment or removal/replacement of any unsuitable strata of material.
E.
Any archaeological remains uncovered during the excavation of foundations for the plant shall be reported and investigated.
9.2
The Site Specific Data
9.2.1
General The descriptions of the specified site and relevant details are provided in other sections of the contract document. The general description of the site is contained in Section 1 of the Specification. Site drawings are provided in Volume 3.
9.3
Scope of Civil Engineering and Building Works
9.3.1
General The civil engineering and building works to be provided by the Bidder under the turnkey contract shall comprise the full detailed design, detailing and preparation
of
construction
drawings,
construction,
completion
and
maintenance of all the various foundations, structures, buildings, installations and services, etc., required for the installation, commissioning, operation and maintenance of the equipment and plant for the power plant plus associated pipelines, storm drainage culverts and outfalls. The works will include, but not be limited to the items described in the subsections below. 9.3.2
The Bidder’s enabling works The Bidder’s “enabling” civil works (early civil works) on the site, shall, after completion, allow the “normal” type of construction activities of the project to proceed without delays.
9-4 KHABAT TPP UNITS 1&2 - VOLUME I
The Bidder shall investigate, assess and execute the “enabling” works required on the site. For information purposes, the extent of the enabling works may include but not be limited to the following: A.
the extent of the existing, “live” or redundant buried services which exist and impact on the proposed steam turbine arrangement. Where existing services drawings are supplied they are to be assumed to be provided for information purposes. Services shall be removed or diverted (if “live”) where they clash with the new works.
B.
the extent of the existing buried and above ground civil infrastructure which may impact on the proposed steam turbine arrangement. Principally this shall involve the demolition and removal off-site of any buildings on the site and civil infrastructure which clash in position with the proposed new works.
C.
The existence of any weak soil is to be rectified. The bidder shall determine his own geotechnical design parameters for the design of the foundations which may need to utilize piled type foundations where heavy loads have to be supported. Alternatively, the whole site may have to be treated by an improvement scheme like installing stone columns at regular intervals.The bidder will have to prepare the site to a standard suitable for the installation of an oil fired thermal power plant.
D.
The extent of the earthworks required for the proposed oil fired thermal plant may involve a pre-contract cut and fill operation. The earthworks shall be developed by the EPC Bidder to achieve an optimum arrangement, to satisfy both the site conditions and the operation and maintenance of the plant. This shall address the issues of site flooding and any high ground water table. Salt rich soils on the site should not be re-used as backfill material. The bidder shall ensure that the execution,
control
and
testing
of
earthworks
fulfills
the
project
requirements and complies with the recognized Standards and codes of practice. These will include the American Society for Testing and Materials Standards (ASTM), material codes for grading, and compaction codes to 9-5 KHABAT TPP UNITS 1&2 - VOLUME I
achieve a minimum degree of compaction of [90%] per ASTM D 698. The Bidder shall allow for all dewatering necessary to keep excavations clear of water during construction. 9.3.3
Scope of main civil engineering and building works
9.3.3.1 Summary of scope The proposed main civil works comprising the oil fired thermal power plant include the following: A.
Site establishment (Access to site, storage facilities, construction office, education of site staff, etc.)
B.
Verification/identification
of
existing
buried
services
and
civil
infrastructures C.
Demolition of existing infrastructure impacting with the proposed oil fired thermal power plant
D.
Earthworks and site preparation activities to form proposed platform for the oil fired thermal power plant
E.
Piling(if required) and foundation works for the steam turbine foundations and associated buildings
F.
Construction of all associated buildings, including building services for steam turbine generation operations specified in the contract. The buildings are shown on the bid arrangement drawings
G. New roads, car park, drainage and other yard works, including fencing H.
Consideration of requirements for future extension works
I.
Hydrological survey and route survey
J.
Geo-technical and topographical surveys of the site, the raw water intake and discharge area including ground pollution report.
K.
Hydraulic model study report and hydrological survey including water level data in consideration of the seasonal changes in Greater Zab River.
L.
Route survey along the raw water pipe and discharge pipe.
M. Data collection including verification of design data provided in the Bid documents N.
Enabling works with regard to existing services, earthworks, dewatering and demolitions
9-6 KHABAT TPP UNITS 1&2 - VOLUME I
O. Access roads, site roads, paved hardstanding areas (for car parking, concrete slab laydown areas, gravel covered sterile areas, pathways, street lighting and landscaped areas P.
Utilities pipework
Q. Acoustic attenuation where required to meet noise limits R.
Storm, sewage, oily and plant drainage systems
S.
Utilities and underground services
T.
Security works during construction and operational phases
U.
Permanent Perimeter fence from concrete block wall with additional security camera system and security lighting.
V.
Heavy duty, large rolling type security gate(s) for road access and small personnel access gate.
W. Hard landscaping X.
Concrete slabs for miscellaneous pipe supports
Y.
Piling works and/or ground improvement
Z.
Site services(i.e., power, water, sewage and telephone,etc.) for the Bidder and KNOC office accommodation during the construction period
AA. Building contents (ironmongery, fixtures and fittings, internal finishes, furniture, office computer equipment, fire and safety equipment) BB. Mechanical and electrical building services CC. Builder’s work associated with building services installation DD. Office accommodation during the construction period for the Bidder, and the KNOC Building works, foundations, structures and associated facilities EE. Interfaces with associated contracts FF. Design, preparation of detailed construction drawings, bar bending schedules and all drawings and documents necessary for completion and maintenance of the works GG. Preparation of as-built documentation HH. Buildings, structures, foundation and compounds to be included as a minimum, in the civil works as follows:
Turbine building
Central control building
Boiler and electrostatic precipitator
Stack
Absorber foundation 9-7 KHABAT TPP UNITS 1&2 - VOLUME I
Fan foundation
Clean & dirty lube oil tank foundation with dike
Fuel oil & fuel oil emergency, light oil storage tank foundation and dike
Raw water storage tank foundation
Demi water storage tank foundation
Ash silo foundation
Limestone slurry storage & emergence storage tank foundation
Gypsum dewatering feed & filtrate tank foundation
Chemical storage tank and pump foundation with dike
Transformer foundations and compounds (with fire walls and bund walls)
Switch yard area facilities foundation
Raw water supply system complete with raw water intake structure, pump house, pump foundation and piping
Circulating water system structure complete with cooling tower and cooling water pump station
Discharge basin
Sewage treatment facilities foundation
Waste water treatment facilities foundation with pond
Truck scale foundation
Parking
Pipe rack foundation
Play ground
Aux boiler house
Electrical building
Administration building including toilets, small cafeteria
Operations & maintenance management building
Dining facility building
Prayer facility building
First aid center with 2 rooms
Raw water pump house included electrical facilities
Foam tank house
Fire brigade station
Fuel & light oil pump house
Service gas storage house 9-8 KHABAT TPP UNITS 1&2 - VOLUME I
Workshop building
Warehouse building
Chiller building
Water & waste water treatment building
Security gate house with 2 rooms
Unloading entrance gate house with 2 rooms
Sun shades and rain screens
Black start/emergency diesel generator building
Gypsum dewatering building
Limestone slurry preparation building
FGD waste water treatment building
FGD pump rooms
FGD control building
Guard towers with personal amenities
Building services, including air conditioning of the local control rooms, central control building, special storage areas, toilets and messrooms, prayer facility building and dining facility buildings. Foundations and associated works for:
All buildings, structures and compounds listed above
Steam turbine generators
Transformer compounds
Black start/emergency diesel generator
Fuel oil storage tanks and handling equipment
Service/fire water, potable and demineralized water storage tanks
Fire fighting foam equipment
Compressed air equipment
Miscellaneous plant and equipment
Service ways, silos, ducts and trenches, pipe racks and bridges
All necessary supports, access ladders, stairways, platforms, walkways, sunshades, handrails, etc., for the safety of personnel during plant operation and maintenance
Bunded areas for all lubricating and other oils and chemicals
Rain shelters over all bunded areas
Sump pumps
Sewage water treatment system 9-9 KHABAT TPP UNITS 1&2 - VOLUME I
The buildings shall be aesthetically designed that the appearance shall be in harmony with the surroundings. The total floor areas and structures of the buildings shall be as follows: Total floor
Description
area(M2)
Structure
Turbine Building
-
Steel
Boiler Building
-
Steel
100
Concrete
375
Concrete
Black Start/Emergency Diesel Generator Building Fuel & Light Oil Pump House
Remarks
Two houses
Concrete Central Control Building
-
(Including basement floor
Administration Building
630
Concrete
1,700
Concrete
Dining facility Building
315
Concrete
Prayer facility Building
300
Concrete
First aid center
60
Concrete
Aux. Boiler House
142
Steel
Electrical Building
1,080
Concrete
180
Concrete
Workshop Building
1,500
Steel
Warehouse Building
1,900
Steel
1,800
Concrete
Operations & Maintenance Management Building
Chiller Building
Water & Waste Water Treatment Building
9-10 KHABAT TPP UNITS 1&2 - VOLUME I
Concrete
Foam Tank House
360
Fire Brigade Station
800
Concrete
Security Gate House
70
Concrete
Service Gas Storage House
170
Raw Water Pump House
140
Concrete
Cooling Water Pump House
49
Concrete
Unloading Entrance Gate House
28
Prefab
1,500
Steel
480
Steel
1,000
Concrete
FGD Pump Room
200
Concrete
FGD Control Building
640
Concrete
Guard Tower
25
Concrete
Gypsum Dewatering Building Limestone Slurry Preparation Building FGD Waste Water Treatment Building
(Roof:Steel)
Concrete (Roof:Steel)
Two houses
Four houses
※ The floor areas are approximate and they are subject to equipment sizes which may vary with different manufacturers.
9.3.3.2 Scope/descriptions of main civil engineering and building works The scope of works listed below and the descriptions provided, are not intended to cover every particular aspect of the oil fired power plant works, but are intended to assist the Bidder to develop, design and construct the most suitable arrangement of civil engineering and building details to fulfill the requirements of the contract. In addition to the items described below, the Bidder shall make full allowance in his price and programme to carry out all investigations, surveys, demolition and removal of all buried structures and services impacting upon the new
9-11 KHABAT TPP UNITS 1&2 - VOLUME I
works,
including
excavation
of
any
unsuitable
materials,
importing
replacement materials, site preparation, filling, site grading, and flood prevention in order to design and construct the works. The new thermal power plant works shall comprise, but will not be limited to, the individual areas for the various plant items and buildings, separately or combined as follows: 9.3.3.3 Turbine building Particular attention shall be given to the design of the foundations for the steam turbine to ensure that all criteria including vibration, thermal effects, short circuit torque forces and mechanical resonance and critical concrete tolerances are fully accommodated. The Bidder shall determine his own requirements to suit the plant arrangements, loadings and soil conditions. The steam turbine shall have an isolated supporting structure. The foundation structure shall have sufficient mass so that the plant can be supported and operated without the risk of vibration damage from the supporting structure or the soil underneath when acting together. The mass of the top deck shall not be less than 2.5 times the plant weight. The dimensions of the supporting structure shall be verified by static and dynamic calculations covering all the possible operating and emergency conditions. The supporting structure shall be designed so that no permanent damage or overstress can be resulted from abnormal or faulty operating conditions. Adequate clear working space between units for laydown and loading bays shall be provided. The bidder shall propose a working space and obtain approval of the same during early development of the plant arrangement. Laydown and loading bays shall be paved areas of adequate strength for their applications. A turbine building shall be provided to house the steam turbine generator unit. An overhead travelling crane shall be provided to enable the steam turbine generator to be serviced and maintained within its weather-protected environment and on dedicated laydown areas.
9-12 KHABAT TPP UNITS 1&2 - VOLUME I
A separate operating floor of reinforced concrete construction and safety hand rails shall be provided for access and operating the plant. Paved area of the steam turbine building shall be suitably painted, dust free and of sufficient thickness to withstand heavy use of loading and unloading of heavy mechanical components. The turbine building should be a heavy steel-framed superstructure with masonry or concrete walls of suitable height at the ground level. Steel roller shutter doors of suitable size and metal personnel access doors shall be provided to fulfill the operating and maintenance requirements. The ground floor slab between the turbine generator blocks shall incorporate trenches and be constructed of reinforced concrete and laid to falls to floor drainage gullies discharging into oily water separators. Trench covers shall be designed to accept the appropriate floor loadings according to their location and shall be manually removable, wherever possible. Drainpipe routes shall be routed clear of all electrical equipment. 9.3.3.4 Raw water supply system The raw water supply system shall mainly supply raw water to the raw water storage tank. The raw water supply system shall consist of the followings but not be limited. - Raw water intake canal. - Raw water pump structure with oil/trash removal equipment - Raw water pump house - Raw water pipelines from raw water pump house to raw water storage tank. A. Raw water intake canal Raw water approach channel shall be designed to supply raw water in appropriate quality and quantity from river to circulating water station. The design of raw water approach channel shall be considered as follows; - Intake flow velocity 9-13 KHABAT TPP UNITS 1&2 - VOLUME I
- Entrance of river weed and sediments - River bottom dredging for good flows - Approach angle for good flow - Good Pump design - Maintenance dredging to remove sediment that may accumulate The intake flow velocity has a significant effect upon the size of the intake channel and entrance of floating material and sediments into the system. Therefore, intake channel shall be designed according to hydraulic model study results. B. Raw water pump house The typical design of this type of intake pump house consists of a curtain wall, trash racks and screen to block debris and fish. The size and depth of the pump house shall be governed by the various water level conditions, pump requirements, design approach velocities, and International Standards. Since the pump must be remain functional under extreme low water level conditions, the depth of the intake chamber will be governed by the pump submergence at extreme low water conditions.
Other dimensional
requirements, such as pump spacing, distance between pump and screen and width of the chamber shall be investigated to provide good hydraulic design of the system. The size of the intake, stilling, screening and pump bays shall be designed for streamline flow causing minimum energy loss and degradation of plant efficiency, all in accordance with manufacturers’ recommendations. Trash racks and screens shall be provided at the inlet to pump structure waterway to prevent large and small objects and fish from entering the pump chamber. Stop gates shall be provided to isolate one section from another within the raw water supply system for the purpose of dewatering. The design approach velocities of trash rack and traveling screen shall conform to the limit value provided by manufacturer and applicable
9-14 KHABAT TPP UNITS 1&2 - VOLUME I
environmental regulations. Housing the mechanical cleaning plant, a crane for maintenance and handling of stop logs have to be installed. The waste and debris container shall be located south of the structure. C. Piping All circulating water piping shall be used of GRP or Steel pipes. The final selection of material type and size shall be based on technical considerations (corrosion and design life), and economic considerations (construction costs, maintenance costs, and pumping costs). The pipes shall be sized to resist for all load cases, i.e. traffic load, earth pressure, internal and external water pressure and seismic load, etc. 9.3.3.5 Circulating water system The circulating water system shall mainly supply circulating water to the ST condenser and via a by-pass line to the cooling water cooler. The circulating water system shall consist of the followings but not be limited. - Cooling tower. - Cooling water pump station. - Circulating water intake pipelines from cooling tower pump house to ST condenser. - Re-circulating water pipelines from condenser to cooling tower. - Blow down pipelines from cooling tower to discharge basin. The cooling water pump station is required to house the cooling water pump and electrical panels. 9.3.3.6 Boiler house and precipitator support structure The Bidder shall provide a suitable building structure included elevator for each units to support fully functional steam boilers and their auxiliaries as described in the mechanical section of the specification. The boiler superstructure shall be steel-framed. The boiler superstructure shall be substantially clad to form a suitable weather protection canopy/sun-shield as noted in 6.1.1 and shall be founded on a substantial foundation system to minimize differential settlement that may cause damage to the piping system and services. 9-15 KHABAT TPP UNITS 1&2 - VOLUME I
9.3.3.7 Black start/emergency diesel building The Bidder shall determine the requirements for foundation supports. A fully enclosed building with exhaust stack shall be provided for the black start/emergency diesel generator plant to ensure the equipment is always available as an essential facility and free from damage and degradation from the elements. The foundation for the black start/emergency diesel package units shall be sized to accommodate the plant to be installed and to facilitate the operation and maintenance of the plant. Galvanized chequer plate sub floors and trench systems shall be provided as necessary to facilitate access to the fuel piping, pumps, input and output cables. Floors and trenches shall drain to floor gullies connected into the drainage system via an interceptor. A diesel fuel tank contained within bunded walls shall be provided outside the building. 9.3.3.8 Transformer foundations and compounds (with fire walls and bund walls) The Bidder shall determine the foundation requirements for foundation supports. Dimension of the transformer compound shall be adequate to enable maintenance requirements, beside installation, operation and the transformer removal. The transformer support substructures shall be designed to contain any escaping oil. The oil retaining structures shall be covered with a layer of fire quenching graded round stones a minimum of 200 mm thick supported by a steel frame including an open grid steel grating. An air void capacity at least 10% in excess of the transformer total oil volume and deluge water in FF system shall be provided. Segregated ducts shall be provided for any cables installed within the substructures. The transformer support structure shall incorporate guide rails for transformer installation and withdrawal. 9-16 KHABAT TPP UNITS 1&2 - VOLUME I
Each compound shall be connected to the site storm drainage system via oil/water separators with water outlets drains and oil retaining chambers by gravity or pumping out facilities. The compounds shall also be connected via larger diameter pipes to a common holding tank capable of storing the total oil and deluge water quantity for the largest transformer. Each compound shall be provided with fire resistant walls to sides and rear to prevent fire spreading from one compound to another and to the steam turbine area. Fire walls shall be designed for a minimum 3 hours fire resistance. Height of fire walls shall be higher than the transformer highest point by 50 cm in order to prevent spreading of fire. All trenches in the compounds shall be filled with sand and be sealed to prevent the passage of oil or spread or fire and water into buildings. The dimensions of each compound shall be adequate for installation, operation and removal, and to allow for sufficient cooling of the transformers. Hauling bollards shall be provided as required. The front of each compound shall be provided with a close fitting robust, easily removable, framed aluminium fence incorporating a personnel gate. The road in front of the enclosures shall be of concrete construction. 9.3.3.9 Stack and flues Suitable reinforced concrete windshield(s) and foundation(s) shall be provided to the boiler exhaust flues. The layout of the flues shall be such as to provide the optimum design of the windshield whilst taking the plant layout into consideration. The flues shall be adequately supported within the windshield with sufficient allowance made for the thermal movements of the flues. The design of the flues and windshield shall meet the height requirements to satisfy the environmental regulations in force taking into account all the prevailing background pollutants that may be present on the existing site. The Bidder shall determine the requirements for foundation supports. 9-17 KHABAT TPP UNITS 1&2 - VOLUME I
The area surrounding the stack shall be surfaced with a concrete slab. A fully integrated drainage system, including wash down discharge, shall be provided. Chemically polluted discharge and wash down effluents shall pass into a suitable designed pit. Foundations shall be provided for each stack, and shall be designed to withstand the most unfavorable combination of static, dynamic, environmental and erection loads. A.
The stack shall consist of the following structures/facilities:
- Reinforced concrete foundation - Reinforced concrete outer shell - Steel inner flues with lining and insulation
- Aircraft warning lights - Lift car shall be supplied or not according to local regulation - Lightning protection system - Miscellaneous steel works such as platform, stair, ladder etc. - Interior lighting system - Water supply and drainage system
B.
-
Concrete roof with waterproofing
-
Painting Outer shell 1) General The outer shell of stack shall be of reinforced concrete and shall have a concrete roof slab with waterproofing to prevent ingress of rain water. The top of the stack shall be made weather proof and the reinforced concrete roof shall be protected with heat and acid resistant paint. The structure of outer shell shall be designed taking into consideration seismic force, wind force and temperature stress, etc. 2) Slip form The following specification shall be applied to the slip form work to be used in construction of reinforced concrete outer shell: (a) Sliding of slip forms shall be performed at an appropriate speed, taking into consideration the strength of concrete and the bonding strength of the form. 9-18 KHABAT TPP UNITS 1&2 - VOLUME I
(b) When sliding the slip form after prolonged suspension of concreting, adequate measures shall be taken so as not to damage the concrete by the adhesion of the slip form. (c) The work shall be suspended during rain, strong wind, low temperature, or whenever there is danger of adverse effect to concrete. (d) The bidder shall establish Bidder's standards for slip form equipment and safety control during the execution of works, which shall be subject to the approval of the KNOC. (e) Prior to the commencement of the works, the Bidder shall submit an execution plan incorporating the tolerances required for the height, wall thickness, plumbing, roundness, etc. to the KNOC for his approval. C.
Inner flue, platforms and stair/ladders 1) General Two inner flues with flue lining and insulation as specified hereafter and platforms shall be arranged inside the outer shell. Platforms for maintenance at hopper part and top part of inner flues shall be provided taking into consideration operation and maintenance of plant. The Bidder shall prepare their proposal of numbers, levels and area of platforms and submit them to the KNOC for his approval. Stairs shall be arranged from ground floor to top main platform located by gas sampling measurement, and ladders shall be arranged from main platform to roof of the outer shell where the access hatch shall be arranged. Access to additional platforms shall be designed by the use of stairs, unless otherwise specified.
Additional platforms and
access hatch, etc. above the reinforced concrete roof shall be galvanized. 2) Materials and workmanship (a) All structural steel for main part of inner beams for platforms, stairs, ladders, soot hopper, flue terminal shall comply with the requirements of ASTM A36 for SS400 or equivalent.
Specifi-
cations and workmanship for other materials shall be according to Clause 9.6 of this document. (b) All stainless steel for top of flue and others shall be of SUS 316 or approved equal and of a grade suitable for welding conforming to 9-19 KHABAT TPP UNITS 1&2 - VOLUME I
relevant standards. (c) All galvanization of steelwork shall be in compliance VOL 1.Technical Specification in the Bid Document. 3) Fabrication and erection of steel flues Unless otherwise approved by the KNOC, each segment of steel flue shall be shop fabricated.
The Bidder shall provide temporary
stiffeners and bracings to each segment to ensure roundness and stability of the segments and to avoid overstress during transportation and site erection. The supply and subsequent removal of the temporary stiffeners and bracings is the Bidder’s own cost. Each fabricated segment shall be erected and jointed on site by welding upon the completion of outer shell construction. The Bidder shall provide all necessary erection plant and shall submit his erection method to the KNOC for his approval. 4) Top of flue The top part of flue projecting above the reinforced concrete roof shall consist of sulfuric acid and hydrochloric acid dew-point corrosionresistant steel with steel stiffeners to protect from acid reaction. The gap between steel shall be with insulation. Entire portion of the flues projecting above the top of reinforced concrete floor shall be painted with heat and acid resistant paint to protect the outside surface from acid reaction. 5) Gas sampling/measurement apertures Gas sampling/measurement apertures consisting of various internal diameter stainless steel pipes complete with stainless steel easily removable blank flanges shall be provided in each inner flue. 6) Doors and louvers The Bidder shall provide the following accesses to window shield and steel flues. The Bidder shall prepare detail drawings of these doors and submit it to the KNOC for his approval. Paint for the external doors shall be UV resistant. Louvers shall be provided below roof level for ventilation. 7) Flue openings The concrete shell at the flue entries and at openings shall be adequately protected against high temperature by lining material. 9-20 KHABAT TPP UNITS 1&2 - VOLUME I
Adequate arrangement shall be made to seal the air gap between the shell and lining against ingress of flue gases. D.
Insulation The Bidder shall provide insulating material on the external face of inner flue and the flue ducts supplied and installed under the scope of the stack. Materials and thickness of the insulation shall be decided to prevent gas emissions from becoming the dew-point temperature. In addition, materials and thickness of insulations shall be selected so that gas emission temperature does not become the acid dew-point and be able to keep the highest running cost merit. All insulation material shall be to the approval of the KNOC and shall be acid resisting and capable of withstanding sulphuric acid, asbestos free, vermin proof, non-hygroscopic, chemically inert when both wet and dry and fire resistant and rot and fungus proof.
E.
Steel flue lining In order to protect the steel flue from corrosion and erosion induced by flue gas, the material and thickness of linings shall be satisfied and shall be guaranteed for a period of 25 years. The bidder shall submit its specification to the KNOC for approval. All joints and potential weak spots more susceptible to acid attack shall be identified and special treatment provided for the product.
F.
Painting of outer shell The stack chimney shall be painted so as to conform to the requirements and color to be selected shall be to the approval of the KNOC. The paint shall be anti-sulfurous acid paint subject to the approval of the KNOC and shall be guaranteed to retain its color and be maintenance free for a minimum of 15 years. Details of the paint and its performance shall be provided with the Bid. The bidder shall provide rails at the top of the stack to allow the use of painter’s cradles for inspection, maintenance and repainting of the outer shell.
G. Rainwater drain pipe The Bidder shall provide rainwater drain pipe from the roof to the ground floor, rainwater pit on the ground floor and drain pipe from the said pit to the road drainage, which shall be designed taking into consideration rainwater condition during storm, subject to approval of the KNOC. 9.3.3.10 Fuel oil and emergency storage tanks, fuel and light oil pump house 9-21 KHABAT TPP UNITS 1&2 - VOLUME I
Fuel oil and emergency storage shall be provided within suitably bunded areas. The fuel oil tanks shall be supported on suitable foundations incorporating piled (if required) reinforced concrete ring beams. This is to be determined from the Bidder’s investigations and technical assessment of the geotechnical parameters of the subsoils. A surface water drainage channel shall be laid around each tank. The surface within the bund area shall be sealed to prevent the seepage of oil into the substrata. All drainage including that from the tank roofs shall be passed into an oil interceptor system before passing into the site drainage system. The whole system shall be designed to meet the current standards and practices for drainage work of this nature. The oil pump house shall contain trenches with removable covers or ducts (for cable and pipes), concrete plinths for mounting pumps and electric motors, and facilities for supporting all control equipment, pipes and cables. If practicable, the fuel oil electrical buildings may form part of the oil pump house. Floors in the pump houses shall be laid to falls leading to drainage channels connecting into oil interceptors. Oil interceptors and sumps serving the fuel oil system are to be equipped with oil/water or level detectors with alarms. Suitable bunding shall be constructed to prevent any spilt oil entering into the ground. All ducts and trenches shall be sealed to prevent oil entering into the adjacent ground. Suitable barriers shall be provided to prevent damage to pipe works and valves.
9-22 KHABAT TPP UNITS 1&2 - VOLUME I
9.3.3.11 Site area for fuel gas receiving compound/area The Bidder shall be responsible for connecting to the gas pipeline and for the provision of all gas conditioning equipment and their associated foundations. This preparation for the gas compound area shall, as a minimum, consist of stripping a minimum of the top 350 mm of soil, leveling and rolling the subgrade; placing a geotextile membrane over the area capped with a minimum of 150 mm compacted approved granular fill and 200 mm reinforced concrete, to bring back to the same level as the surrounding site. The Bidder shall determine precisely what the preparation of the Site is to be, to match the foundation and layout arrangements for the area. Sun shades, security fencing and gates shall be provided. The layout and location of the gas receiving station/compound shall include suitable considerations of fire and explosion risks to the operational staff and the overall safety of the station. 9.3.3.12 Central control building The central control building shall be designed for all requirements specified to achieve the most suitable and convenient arrangement. The planning of the building shall be carefully considered to form a pleasing, functional arrangement, with a high standard of architectural design which is to integrate with the overall design concept for the remainder of the site. All fixtures, fittings and finishings shall be of good quality, appropriate to their function and location within the building. The floor to suspended ceiling height for all rooms shall not be less than 3 metres. Suspended ceilings shall be provided throughout. Light fittings and ventilation grills, etc., shall be flush fitting, and all ducts, pipes and services shall be concealed above the ceiling. Doors provided solely as a means of escape shall be fitted with panic bars and shall not be openable from the outside. Solar reflective double glazing shall be provided throughout to all windows and 9-23 KHABAT TPP UNITS 1&2 - VOLUME I
doors. Opening lights shall be provided for a proportion of all window areas. The central control room shall have no columns in the interior space to obstruct the view of control panels. All offices shall be fully furnished to a standard and style appropriate to the proposed occupancy. The Bidder shall provide as a minimum the following accommodation in the central control building: A.
Central control room
B.
Computer room
C.
Computer maintenace room
D.
Operations manager office
E.
Shift engineer office
F.
Lock out tag out permit issue office
G. Waiting room H.
Document & storage room
I.
Conference room (large size)
J.
Small kitchen – coffee/tea (with sufficient space for a small seating area 6 people)
K.
Office supply storage room (Capacity for all office supplies and spare equipment)
L.
Toilets-general (separate male /female toilets with capacity for number of office staff)
M. Shower facilities (shower block facility, for male /female personnel) N.
Lockers/change room for male & female personnel (including lockers for all shift workers)
O. Cleaners store (sufficient capacity for storage of cleaning products and equipment) P.
All fittings, furniture & equipment for the above
Externally a 1.5 m wide pathway shall be provided all around the building with access to the entrance and escape doors. This path shall be edged with curbs set in concrete and surfaced with precast concrete paving slabs. 9-24 KHABAT TPP UNITS 1&2 - VOLUME I
9.3.3.13 Administration building
The administration building shall have a high standard of architectural design and finishes throughout and all fixtures, fittings and finishings shall be of good quality. The appearance of the building shall be carefully considered to form a pleasing yet functional arrangement. The floor to suspended ceiling height for all rooms shall not be less than 3 metres. Suspended ceilings shall be provided throughout. Light fittings and ventilation grills, etc., shall be flush fitting, and all ducts, pipes and services shall be concealed above the ceiling. Doors provided solely as a means of escape shall be fitted with panic bars and shall not be openable from the outside. Solar reflective double glazing shall be provided throughout to all windows and doors. Opening lights shall be provided for a proportion of all window areas. The Bidder shall provide as a minimum the following accommodation in the administration building: Offices for the following staff: A.
Plant manager office (ensuit, sufficient space for small meeting area for 610 people)
B.
Office manager office (close to secretary & plant manager office)
C.
Secretary office (adjacent to plant manager office)
D.
Human resources office (capacity for 15 personnel)
E.
Accounts office (capacity for 15 personnel)
F.
Office space – others (see Note below)
Note : Total anticipated administration staff will be 50 people. The following rooms are also required in the same area:
9-25 KHABAT TPP UNITS 1&2 - VOLUME I
G. Small kitchen – coffee/tea (with sufficient space for a small seating area 6 people) H.
Conference room - large (table for 20 + space for 20 additional seating)
I.
Training room (seating room for 40)
J.
Reception desk (sufficient space for a large desk)
K.
Reception area (include seating room for 6-10 people)
L.
Copier /printer room ((sufficient room for printers, copiers, consumable storage)
M. Office supply storage room (Capacity for all office supplies and spare equipment) N.
Server room (capacity for server racks, IT tools & equipment)
O. Toilets-general (separate male /female toilets with capacity for number of office staff) P.
Shower facilities (shower block facility, for male /female personnel)
Q. Cleaners store (sufficient capacity for storage of cleaning products and equipment) R.
All fittings, furniture & equipment for the above
Externally a 1.5 m wide pathway shall be provided all around the building with access to the entrance and escape doors. This path shall be edged with curbs set in concrete and surfaced with precast concrete paving slabs.
9.3.3.14 Operations & maintenance management building
The operations & maintenance management building shall have a high standard of architectural design and finishes throughout and all fixtures, fittings and finishings shall be of good quality. The appearance of the building shall be carefully considered to form a pleasing yet functional arrangement. The floor to suspended ceiling height for all rooms shall not be less than 3 metres. Suspended ceilings shall be provided throughout. Light fittings and ventilation grills, etc., shall be flush fitting, and all ducts, pipes and services shall be concealed above the ceiling. Doors provided solely as a means of escape shall be fitted with panic bars and shall not be openable from the outside. 9-26 KHABAT TPP UNITS 1&2 - VOLUME I
Solar reflective double glazing shall be provided throughout to all windows and doors. Opening lights shall be provided for a proportion of all window areas. The Bidder shall provide as a minimum the following accommodation in the operations & maintenance management building: Offices for the following staff: Total anticipated staff in this office will be 100 people. A.
Operations manager office (1 office)
B.
Maintenance manager office (1 office)
C.
Mechanical group manager office with engineers (see Note below)
D.
Electrical group manager office with engineers/technicians (see Note below)
E.
I & C group manager office with engineers/technicians (see Note below)
Note : Manager separate office to engineers/technicians, but must be adjacent to managers office F.
Planning manager office with planners/schedulers (combinde office)
G. Training manager office with engineers (combinde office) H.
Safety manager office with engineers (combinde office)
I.
Quality assurance office with quality engineers/procedure development engineers (combinde office)
J.
Technical
services
office
with
airconditioning
technician/plumber/
mechanic (combinde office) K.
Grounds keeper office
The following rooms are also required in the same area: L.
Small kitchen – coffee/tea (with sufficient space for a small seating area 6 people)
M. Training room (seating room for 40) N.
Copier /printer room ((sufficient room for printers, copiers, consumable storage)
9-27 KHABAT TPP UNITS 1&2 - VOLUME I
O. Office supply storage room (Capacity for all office supplies and spare equipment) P.
Server room (capacity for server racks, IT tools & equipment)
Q. Toilets-general (separate male /female toilets with capacity for number of office staff) R.
Shower facilities (shower block facility, for male /female personnel)
S.
Cleaners store (sufficient capacity for storage of cleaning products and equipment)
T.
All fittings, furniture & equipment for the above
Externally a 1.5 m wide pathway shall be provided all around the building with access to the entrance and escape doors. This path shall be edged with curbs set in concrete and surfaced with precast concrete paving slabs.
9.3.3.15 Dining facility building
The Bidder shall determine the superstructure and foundation requirements for the dining facility building. The building shall be architecturally sympathetic to the elevations adopted for the administration building. The Bidder shall provide as a minimum the following accommodation in the dining facility building: A.
Dining area (seating capacity for 100 people – 2 x 100 people per meal sitting)
B.
Kitchen (see Note below)
C.
Pantry food storage (see Note below)
D.
Refrigerated room (see Note below)
E.
Washing area (see Note below)
F.
Serving area (see Note below)
Note : Capacity to serve up to 200 hot meals per sitting. G. Hands washing station /area (outside, separate foyer, to main dining area) H.
Male /female toilets – general (outside, separate foyer, to main dining area) 9-28 KHABAT TPP UNITS 1&2 - VOLUME I
I.
All fittings, furniture & equipment for the above
9.3.3.16 Prayer facility building
The Bidder shall determine the superstructure and foundation requirements for the prayer facility building. The building shall be architecturally sympathetic to the elevations adopted for the administration building. It shall be fully furnished with all fixed equipment supplied and of a size commensurate with the maximum number of employees anticipated to be on site during an outage. The Bidder shall provide as a minimum the following accommodation in the prayer facility building: A.
Prayer room (main room)
B.
Wash room (outside of main prayer room, but attached to the building)
C.
Toilets (for male /female personnel)
D.
All fittings, furniture & equipment for the above
9.3.3.17 First aid center
First aid center shall be located near to the administration building. The Bidder shall provide as a minimum the following accommodation in the first aid center: A.
Room 1 (office 2 x desk space & sufficient space for seating of 6 people)
B.
Room 2 (examination room with 2 bays/beds)
C.
Storage (walk in store, securable)
D.
Toilet (single unit only)
E.
Wash basin /sink
F.
All fittings, furniture & equipment for the above
9.3.3.18 Auxiliary boiler house
9-29 KHABAT TPP UNITS 1&2 - VOLUME I
The auxiliary boiler house shall be sized to accommodate the plant to be installed and to facilitate the operation and maintenance of the plant. A fully enclosed building shall be provided for the auxiliary boiler and accessories to ensure the equipment is always available as an essential facility and free from damage and degradation from the elements. The Bidder shall determine the foundation requirements for the auxiliary boiler and electrical room. The PLC based control cubicles and minimum one(1) operator interface station with dual LCD monitors and printer shall be provided in electrical room. Auxiliary boiler and accessories shall be designed for the seismic factor and wind loading in this specification. Doors shall be provided to allow large items of plant to be brought in for maintenance.
A personnel door shall be positioned beside the main door.
9.3.3.19 Electrical building The dimensions of the Electrical building shall provide sufficient space for efficient equipment and shall be located near to the turbine building. The Bidder shall provide as a minimum the following accommodation in the electrical building: A.
Battery room
B.
MCC & UPS room
C.
Electronic room
D.
Electrical maintenance room
E.
Communication room
9.3.3.20 Chiller building The Bidder shall determine the superstructure and foundation requirements for the infrastructure housing the chiller plant. The provisions shall be such as to 9-30 KHABAT TPP UNITS 1&2 - VOLUME I
enable the chiller plant to be installed properly, to shield the equipment from damage from the environment, to operate equipment satisfactorily and ultimately to be able to carry regular maintenance work on the plant with suitable spaces and facilities under a protected environment. The chiller building shall be suitably sized to house the chiller plant required for the station. Furthermore, the chiller building shall contain, where applicable, a separate area for switchgear, offices and toilets with a mezzanine floor above for housing the air conditioning units for the chiller building. Galvanized chequer plate covers shall be provided as necessary to facilitate access to trenches which shall contain all pipeworks, cabling, etc., within the building. Floors shall be laid to fall away from equipment and trenches to floor drainage gullies connected into the drainage system. An area for the chiller cooling system shall be provided external to the main chiller building to be housed within a louver sided compound to prevent the ingress of sand and dust. The chiller plant area shall be served by an overhead electric crane or hoisting facilities suitable for maintenance of the chiller plant. Doors shall be provided to allow large items of plant to be brought in or removed for maintenance. Personnel doors shall be positioned beside the main doors. The offices shall be fully furnished and ready in all respects for occupation. 9.3.3.21 Workshop building The Bidder shall determine the foundation requirements. The workshop shall be fully equipped with all necessary machine tools, work benches, hand tools, etc., shelving and fittings for the storage of all tools and materials. It shall be provided with an overhead travelling electric crane and other necessary lifting equipment. A building is required to house the stores equipment which is specified in Section 6.22. The dimensions of the workshop shall provide sufficient space for efficient working on all plant and equipment as necessary to maintain the normal running of the station.
9-31 KHABAT TPP UNITS 1&2 - VOLUME I
Doors shall be provided to allow large items of plant to be brought in for maintenance.
A personnel door shall be positioned beside the main door.
The offices shall be fully furnished and ready in all respects for occupation. The tools storage room shall be fitted with shelving and racking suitable and sufficient for the satisfactory operation of the station in all circumstances. The workshop records room shall be fitted with filing cabinets and shelving. The following rooms are also required in the same area: Mechanical & welding workshop : include office with space for 4 desks, drawings storage & viewing table : include tools storage room : include 2 welding bays with arc radiation protective walls /screens Electrical & instrumentation workshop : separate area /partition to the mechanical portion of the workshop : separate airconditioned and dust proof calibration room All fittings, furniture & equipment for the above
9.3.3.22 Warehouse building
Warehouse building shall be provided with an overhead travelling electric crane and other necessary lifting equipment. And building shall be provided to suitable storage conditions for plant spare parts, consumables etc. A building is required to house the stores equipment which is specified in Section 6.22. Doors shall be provided to allow large items of plant to be brought in for maintenance.
A personnel door shall be positioned beside the main door.
The offices shall be fully furnished and ready in all respects for occupation. The Bidder shall provide as a minimum the following accommodation in the warehouse building: 9-32 KHABAT TPP UNITS 1&2 - VOLUME I
A.
Warehouse office (sufficient space for 4 desks)
B.
Indoor storage (sufficient capacity for pahse 1 & 2)
C.
Outdoor storage area (sufficient capacity for pahse 1 & 2)
D.
Hazardous consumables storage area with ventilation (sufficient capacity for pahse 1 & 2)
E.
All fittings, furniture & equipment for the above
9.3.3.23 Water and waste water treatment building The water and waste water treatment plant will comprise raw (service) water and demineralized storage tanks, pump stations, water quality control equipment, sampling laboratory & analysis and waste water treatment equipments. The scope of the civil works shall include all provisions necessary for the above. The Bidder shall determine the foundation requirements for the bulk storage tanks, pumps and the building etc. The bulk storage tanks shall be supported on suitable foundations. A building shall be provided incorporating the following facilities: A.
Chemical stores. Adequate storage shall be provided to accommodate all of the chemicals required for operation and maintenance of the water treatment plant and dosing equipment. Provision shall be made for appropriate washing and first aid facilities adjacent to each store. Adequate facilities shall be provided for the safe handling of all chemicals. Air-conditioned storage space for reagents and space for storage of glassware and spare items shall be provided.
B.
Chemical laboratory. A fully equipped laboratory for the testing required for the plant shall be provided within the building.
C.
Fire water pump, Service water pump
9-33 KHABAT TPP UNITS 1&2 - VOLUME I
All necessary furnishing shall be provided to ensure adequate operation of the laboratory. The structure design shall allow for the use of cranes and lifting tackle for removal of plant. A suitable plant unloading area shall be constructed. The ground floor slab shall be reinforced concrete suitable for supporting all the plant and maintenance loadings. The surface shall be suitably treated or painted to resist the chemicals used. Spilled chemicals shall be confined by perimeter bund walls. Removable duct covers and manhole covers shall be provided over permanent cable and pipe trenches and chambers. These covers shall be designed to accept the appropriate floor loadings according to their location and shall be provided with proper and adequate sealing. Chemical resistant covers and frames shall be provided in chemical handling/storage areas. The bulk chemical store flooring shall be chemical resistant and be suitable for forklift movements to be used for chemical stacking purposes. Emergency exit doors shall be provided, except to toilets, fitted with panic bar type of operation. The building shall be ventilated and lighted as required. For plant operation or maintenance, allowance will be made for discharge or spillage of wastewater or other fluid, and adequate provision shall be made for collection and disposal. 9.3.3.24 Foam tank house The Bidder shall determine the foundation requirements for the foam tank house and storage tank. The foam tank house shall be sized to accommodate the plant to be installed 9-34 KHABAT TPP UNITS 1&2 - VOLUME I
and to facilitate the operation and maintenance of the plant. Galvanized chequer plate sub-floors shall be provided as necessary to facilitate access to the pumps. Floors shall be laid to fall away from pumps and trenches to floor drainage gullies connected into the drainage system via an oil interceptor. A diesel fuel tank contained in bunded walls shall be provided outside. A foam tank and distribution pipeworks shall also be supplied and installed under this contract, details of which are given in this Specification. 9.3.3.25 Pipe rack, silos and foundations The Bidder shall determine the superstructure and foundation requirements for the ash handling infrastructure. The provisions shall be such as to enable the ash handling plant to be installed properly, to shield the equipment from damage from the environment, to operate equipment satisfactorily and ultimately to be able to carry regular maintenance work on the plant with suitable spaces and facilities under a protected environment. 9.3.3.26 Security gatehouse A fully functional security gatehouse shall be provided adjacent to the main access gate to the site. It shall be of adequate size to fit its purpose. The building shall contain controls for operating main gates, lifting barriers and any installed turnstiles plus the CCTV system. There shall also be a security staff working area with reception desk, visitor waiting area, private office, welfare facilities comprising kitchen/staff room and toilet, plus an adequate filing area and storeroom. It is a requirement of the contract that adequate provisions shall be installed to deter forcible entries by motorized vehicles from the outside. The gate house therefore should be adequately strong. Additional security measures, if required, shall be specified in the general conditions of the contract. 9.3.3.27 Unloading entrance gate house The house shall be provided adjacent to the unloading entrance gate to the site. The house shall contain a working area and toilet. 9-35 KHABAT TPP UNITS 1&2 - VOLUME I
9.3.3.28 Service gas storage house The service gas(N2) storage house shall be provide for unit preservation against oxidation during long periods of plant shut down. The building shall be arranged to comply with the appropriate standards and safety regulations with provisions for easy removal of gas bottles. The house is to be constructed with a reinforced concrete wall and finished with a profiled, insulated color coated sandwich panel roof cladding system.
9.3.3.29 Fire brigade station The building is required to accommodate fire fighting staff, two fire trucks, tools and equipment, and may also house the AC and diesel driven fire pumps and associated equipment. Doors shall be provided to allow large items of plant to be brought in for maintenance.
A personnel door shall be positioned beside the main door.
9.3.3.30 Gypsum dewatering building This building is where the vacuum belt filter, the hydrocyclone, the relevant tanks and pumps are installed to dewater the gypsum slurry bleeding from the absorber. 9.3.3.31 Limestone slurry preparation building This building is where the limestone powder storage silo, the screw feeder, the relevant pumps and tanks are installed to make limestone slurry and transfer the product slurry to the absorber. 9.3.3.32 FGD waste water treatment building This building is where FGD waste water facilities such as the clarifier, thickener, heat exchangers, the evaporators, the vacuum dryer, centrifuge, the relevant pumps and tanks are installed to meet waste water discharge limits. 9.3.3.33 FGD pump room The FGD pump room is where absorber recirculation pumps, oxidation air blowers, gypsum bleed pumps and absorber density pumps are installed. 9.3.3.34 FGD control building 9-36 KHABAT TPP UNITS 1&2 - VOLUME I
In the FGD control building, control and electrical panels related to the operation of the FGD system are installed to protect them from the external environment. It is organized with a cable room, electrical room, electronic room, control room and toilet, but not be limited to. The FGD control building shall be designed for all requirements specified to achieve the most suitable and convenient arrangement. The floor to suspended ceiling height for all rooms shall not be less than 3 metres. Suspended ceilings shall be provided throughout. Light fittings and ventilation grills, etc., shall be flush fitting, and all ducts, pipes and services shall be concealed above the ceiling. Doors provided solely as a means of escape shall be fitted with panic bars and shall not be openable from the outside. Solar reflective double glazing shall be provided throughout to all windows and doors. Opening lights shall be provided for a proportion of all window areas. 9.3.3.35 Access roads, site roard, paved hardstanding areas (for car parking), concrete slab lay-down areas, gravel covered sterile areas, pathways, street lighting and landscaped areas Entrance to the site for construction purposes shall be through an existing access or a new access road if specified by the contract. This entrance shall be secure. The Bidder shall construct permanent new access roads and/or shall improve/re-surface existing roads (where retained) such that they meet the design requirements to fulfill the requirements of this contract. Roads shall be a minimum of 7.3 m wide and may be constructed with either asphaltic concrete or concrete pavements, but concrete paving shall be provided where petrol/oil or other chemical spillage may occur. The roads within the site areas shall be constructed between raised kerbs and graded to falls leading surface water into gullies or catchpits that will connect into the drainage system. The Bidder shall take reasonable steps to maintain the free movement of 9-37 KHABAT TPP UNITS 1&2 - VOLUME I
traffic on any roads used by him to gain access to the site.
All roads shall
be maintained free of any spillage from the Bidder’s vehicles. The radii of bends, particularly those at intersections, will be designed to allow for the longest and biggest vehicle necessary for the installation, commissioning, operation and maintenance of the power plant site to take the bend in one manoeuvre without mounting the kerb. Turning areas shall be provided at blind ends. Bollards shall be provided in roadways near equipment, which need protection from vehicular impact. Street lighting shall be provided on all roadways to the latest highway standards. The layout and construction of access roads, paved areas, etc., shall be carefully assessed to effectively serve the power plant arrangement, but also match in to the existing road system(s). Concrete pathways shall be provided for the main pedestrian routes between buildings. Sterile areas shall be covered with rounded stone/gravel. A large open, reinforced concrete slab covered area shall be provided as a storage area required for the life of the station. This area shall be of sufficient size to cater for all eventualities during the lifespan of the site. The area shall be secure and shall have a security fence and large gates. The laydown areas used during the construction period can be refurbished and utilized for these storage areas. A car parking area shall be provided for 80 cars adjacent to the central control and administration building. The car parking facility shall consist of reinforced concrete pavement (laid to falls and draining into the site drainage system) and suitable sun shading. An overflow car parking area shall also be provided 9-38 KHABAT TPP UNITS 1&2 - VOLUME I
at a suitable location to accommodate a further 50 cars. This overflow car park shall consist of a compacted graded granular stone surface of 300 mm depth laid to falls into the site drainage system and suitable sun shading. A minimum size of parking bay clear of sunshade support columns shall be 2.4 m x 4.8 m with a minimum aisle width of 6 m. The overflow car park can be that used for the site construction car parking refurbished to a suitable standard. 9.3.3.36 Drainage systems (storm water, oily water, chemical drainage and sewage water) The quality of all temporary and permanent drainage discharges from the site shall comply with the local authority requirements. The drainage for the power plant shall be designed to collect and transport: A.
storm water, all surface water run-off
B.
oil water, contaminated water from mechanical equipment and fuel storage areas
C.
sewage water, domestic sewage; and
D.
trade effluent, steam generator blow down, cooling tower blow down, chemical wastewater, produced during the operation and maintenance of the plant.
The surface water which refers to the first 5mm of rain shall pass through an oil/water separator. The discharge from the oil/water separator shall contain no visible oil or grease, i.e. less than 10 ppm. The oily water collected from the oil/water separator shall be transferred to the oily water treatment system. The surface water, sewage water, chemical and oily water treated by each treatment system shall be discharged to river through discharge basin. Road gullies shall have removable covers to facilitate the removal of sand accumulated during a sand storm. 9.3.3.37 Site services In addition to the drainage system, referred to above, the site services shall comprise all necessary cables, plant pipeworks, potable water mains, compressed air pipeworks, telephone cables, fuel gas, fuel oil, steam, 9-39 KHABAT TPP UNITS 1&2 - VOLUME I
domestic water for fire fighting, demineralized water, etc. All these services shall be provided to meet the demands identified, to ensure the plant runs effectively.
They shall be located to reduce the amount of excavation, the
number of valves required and the total length of pipeworks needed. This optimization shall be balanced against the needs of other facilities. See also the Sections 9.4 and 9.6 for specification of the design of the works, and the materials and workmanship. 9.3.3.38 Underground cable ducts, drawpits, service trenches, piperacks, etc. Where pipes are to be laid under roads they shall be encased in concrete or laid in trenches with covers. Where cables are to be laid under roads they shall be laid in ducts, grouped and encased in concrete. Trenches for pipes and cables shall be provided in reinforced concrete construction with connections to the site drainage system, to allow dispersal of water from within the trench. They shall be fitted with manually removable, well fitting covers such that they will withstand all loadings from traffic with out rocking or excessive leakage. All overhead pipe runs shall be carried in properly designed structural steel pipe racks. The route location for any pipe rack will be to the approval of the KNOC. Height markers will be provided at all road crossings. Road clearance will not be less than 5 m. All site services shall be indicated on co-ordinated services drawings. The Bidder shall be responsible for the sealing of oil ducts, trenches and wall penetrations to prevent the spread of flame, sand and water. This shall include any duct or opening for future use. Cable drawpits and chambers shall be of adequate size to enable the designated cables to be laid and installed to the correct bending radii. 9.3.3.39 Security fences and gates (columns for security surveillance equipment and site lighting) and guard towers 9-40 KHABAT TPP UNITS 1&2 - VOLUME I
The site perimeter fence shall be closed with a permanent security wall, inclusive of gates, foundations etc. The wall shall be of concrete block wall construction topped with razor wire with security camera and camera lighting. The length of site perimeter fence is about 3.6 kilometers. The main power plant access shall be furnished with a rolling type vehicular gate with a clear opening of at least 8 m, together with the adjacent personnel gate and an electrically operated balancing filter barrier complete with skirt. The gates shall be operable by push button at the gate and from within the gatehouse. The entrance and the perimeter fence shall be monitored by CCTV. Other access points shall be provided around the perimeter as required for normal operation and maintenance and for emergency vehicle access. Perimeter lighting requirements shall be as specified in the building services systems Section 9.7. Each of new 132kV switch yard and transformers areas etc., shall be closed with a galvanized chain link fence with gates providing access. The guard tower shall be located at the inside of site perimeter fence. And it shall be provided with personal amenities. The guard tower shall be based on a reinforced concrete framework and a reinforced concrete block wall.
9.3.3.40 Concrete slabs for miscellaneous pipe supports between buildings, structures, fabricator termination points (to be co-ordinated by the Bidder)
Where required, concrete slabs shall be provided for miscellaneous pipe supports between buildings, structures and fabricator termination points. The supports shall be adequately sized to minimize differential settlement. 9.3.3.41 Building contents (ironmongery, fixtures and fittings, internal finishes, furniture, office computer equipment, fire and safety equipment) All buildings shall be fully completed and functional so that the KNOC can 9-41 KHABAT TPP UNITS 1&2 - VOLUME I
thereafter move in his “loose” furnishings in order to occupy the buildings. All buildings shall be fully fitted out including: ironmongery, fixtures and fittings, internal finishes, furniture, office computer equipment, laboratory equipment, fire and safety equipment etc. The quality and quantity of items supplied shall be commensurate for this type and size of plant and fully adequate for the operation and management of the power plant. The Bidder shall propose exact itineraries and specification for approval by the KNOC. 9.3.3.42 Interfaces with associated contracts The Bidder for the power plant will be required to: A.
where necessary provide the gas pipeline and other bidders with free and unlimited access to their site and interface locations at all times, including provision of a temporary road during construction if required by his pipeline bidder.
B.
attend and hold interface meetings
C.
provide setting out coordinates and datum levels.
9.3.3.43 Miscellaneous foundations and trenches for mechanical and electrical installation Trenches, internal to any facilities for the above, shall be covered with galvanized chequer plate covers. Any floors will be laid to fall away from the trenches. External trenches shall be sealed to prevent ingress of water, or shall be laid to fall so that any ingress of water can be drained to a collection sump and then either gravity connected or pumped to an appropriate drainage system. All ducts shall be laid to fall away from plant or buildings and any water collected in a sump and either gravity connected or pumped to an appropriate drainage system. 9.3.3.44 Builder’s works associated with building services installation All builder’s works associated with building services installation shall be provided by the Bidder. 9.3.3.45 All temporary installations for the construction period, including KNOC’s office 9-42 KHABAT TPP UNITS 1&2 - VOLUME I
The Bidder is responsible for providing all temporary facilities and installation for the contract period. 9.3.3.46 Building services systems The building services systems specification is covered in Section 9.7 of this Specification. 9.3.3.47 Work outside the main site area designated for the power plant The Bidder will be required to provide works which are directly outside the area of the main designated power plant plot of the site, in order to complete his responsibilities under the Contract. The new civil items outside the main site area include but may not be limited to the following: A.
Oil pipelines, buried structures and outfalls
B.
Water pipelines, buried structures and outfalls
C.
perimeter access roads
D.
fencing for raw water pump house area
E.
demolition and removal, of surface and buried infrastructure impacting upon the new works.
The works shall also include other works as described and/or implied in the Invitation to Bidder which are necessary to complete for the satisfactory operation and maintenance of the power plant. The Bidder’s attention is drawn to the fact that other contracts may be in progress on the site during the power plant contract period. The Bidder will be responsible for liaising coordinating and cooperating with these other bidders on or adjacent to the site, and for providing them with free and uninterrupted access at all times to those areas of the site required for their operations. All aspects of the civil works shall be designed and constructed in accordance with the enquiry drawings, specification and basic design data included therein. It is not intended that this specification covers every particular aspect of civil works design and construction. This, however, shall not relieve the Bidder of his responsibility for the satisfactory design, construction, completion and 9-43 KHABAT TPP UNITS 1&2 - VOLUME I
maintenance of the entire civil works, whether specified or not, necessary for the safe and proper operation of mechanical and electrical plant provided under this Contract. The Bidder shall be responsible for obtaining all additional site data required for the project and for complying with local regulations and procedures which may affect the design, construction and completion of the civil works and allow for the KNOC to meet the specified commissioning dates for the Plant. It is essential that the Bidder should visit the site before preparing his Bid for the purpose of examining the extent and nature of the work and means of access to the site, to familiarize and satisfy himself with respect to local and Site conditions and to ascertain for himself the availability of all labour, plant, materials, essential facilities like power, water and drainage discharge points for the satisfactory execution of the works within the overall project . The Bidder’s bid shall be deemed to meet all local and Site conditions and restrictions. 9.4
Design of The Works
9.4.1
General The Bidder shall develop an architectural design philosophy to provide a consistent design solution throughout the site. Unifying elements of materials, color and detailing appropriate to the form and function of the buildings, their location and site, and for the associated plant enclosures and exposed plant should be selected to develop an appropriate theme for the development at the specified site. The development shall be designed for a life expectancy of at least 30 years. The Bidder shall be responsible for developing the overall architectural concept for the power plant, within the guidelines provided in this Specification. With his Bid, he shall submit his proposals for the site layout and the architectural treatment for main and ancillary buildings, taking account of the visual impact and function of the buildings, and their proposed relationship to each other on site whilst fulfilling the requirements set out in this Specification. All buildings shall be designed to ensure that internal noise, vibration, 9-44 KHABAT TPP UNITS 1&2 - VOLUME I
temperature and dust levels are kept within acceptable limits to provide proper operating conditions for the plant which is to be installed and a comfortable working environment for the KNOC’s operations and maintenance staff throughout the year. Noise limitations have been specified around the turbine hall and the design and construction shall fully take this into account. Roofs and walls shall have insulated construction to achieve a ‘U’ value of 0.25 W/m2K or better. The Bidder shall make provision in the designs for the maintenance of all high level buildings, both internally and externally. The architectural concept for the power plant buildings, including colour schemes and finishes schedules, shall be finalized and agreed with the KNOC at an early stage in the design process. The dimensions of buildings shall provide adequate space for the safe installation and operation of all plant and equipment, its replacement, and for maintenance procedures to be carried out by the KNOC. The
design,
engineering,
procurement,
construction,
testing
and
commissioning for the civil works, shall comply with the applicable American Standards and Codes, accepted International Standards and other local laws and regulations, including any applicable maritime regulations. In addition, considerations shall be included to ensure the choices of external materials are durable against erosion by sand storms. Reference to Codes and Standards is intended to provide a minimum measure of performance, design, safety and methods of construction, which must be equaled or exceeded in order to be considered acceptable for use under this Specification. Whilst American Standards are referred to in this Specification, other internationally recognized Standards and Codes are acceptable provided they do not detract from the quality, safety, operability, life, efficiency, reliability, maintainability and durability of the equipment and materials furnished.
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The Bidder shall be entirely responsible for the complete design and design check of the Works. Any assumption regarding design parameters should be stated and agreed with the KNOC. The Bidder shall be responsible for the timely submission to the proper Authorities of details of his proposals for the works, including plant building colors and landscaping schemes as may be necessary in order to comply with all relevant legislation, including building permit approval. Main plant buildings and ancillary buildings shall have structural steelwork frames, with the upper levels and roofs finished with a profiled, insulated color coated sandwich panel cladding system and with concrete or reinforced masonry dado walls at lower levels. Administration and minor buildings may be of reinforced concrete or brickwork construction. The choice of external building materials shall be durable against the sand storm erosion. Buildings shall be designed to comply with the relevant parts of ASTM Standards for fire precaution. Design calculations and analyses shall take into account the most unfavorable combination of static, and dynamic, erection and laydown loads and loads due to temperature and shrinkage effects, to which the structure or component part may be subjected, both for the serviceability and ultimate limit states. Methods of computation and magnitude of loads shall be in accordance with the relevant Standards and Codes of practices. For rotating machinery foundations, the pedestal/foundation/soil system shall be designed for safe operation of the machine at any load within the speed range, without resonant vibration of the whole or any part of the system. Machine foundations shall be suitably isolated from all surrounding floor slabs and structural framing. The Bidder shall provide all building services (electricity, telephone, computer, water, HVAC, fire protection, etc.) and ensure that they are readily accessible for maintenance and repair and adequate clearance is provided from main structural members and foundations. 9-46 KHABAT TPP UNITS 1&2 - VOLUME I
The extent and layout of new roads shall provide suitable access to, and within, the new plant in order to allow erection and maintenance works to be undertaken effectively and with minimum disruption. The dimensions of buildings shall provide adequate space for the safe installation and operation of all plant and equipment and for maintenance procedures to be carried out by the KNOC. All buildings shall be provided with roof drainage for disposal of storm water and be connected to the power plant surface water drainage system. A sewage treatment system for the power plant buildings shall be provided. A waste water system shall be provided for the power plant. The Bidder shall submit a Design Intent Memorandum (DIM) describing the concept and design of the system.
The design should allow for the separate collection,
treatment and disposal of oily wastewater (arising from run-off, plant buildings, oil related operations and from major spillages) and of chemical wastewater (arising from blow down and demineralization systems, etc.). 9.4.2
Preferred structural design concept The structural concepts described below are those preferred by the KNOC and considered appropriate for the specified site conditions and requirements of the Project.
It remains the Bidder’s responsibility under the Contract to
consider these concepts as “information” to assist his own design and development of the civil works. 9.4.2.1 Structural frames It is proposed that the Bidder’s design for all buildings other than the administration building, central control building, dining facility building, prayer facility building, black start/emergency diesel generator building, and gatehouse, etc., shall be based on a structural steel framework. The administration building, central control building, dining facility building, prayer facility buildings, black start/ emergency diesel generator building, gatehouse shall have either a reinforced concrete framework or a structural steel framework. 9-47 KHABAT TPP UNITS 1&2 - VOLUME I
The frameworks of all related buildings shall be set out in such a way so as to allow free access for the installation and maintenance of plant. Structural steel frameworks shall rely on rigid joints for stability or steel bracings, located at strategic locations in walls, roofs and floors to avoid plant access conflicts. Reinforced concrete frameworks shall rely on either rigid joints or reinforced concrete shear walls for stability. Movement joints, to control thermal movements and stresses, in all structural frameworks shall be provided at intervals not exceeding approximately 50 m. 9.4.2.2 Foundations and ground floor construction for buildings
The ground conditions at the proposed site may be poor in terms of the allowable soil bearing pressure, settlement characteristics, high ground water table, and the sulphate and chloride contents in the soils and groundwater. Unless noted otherwise, structural base plates should be above the FGL(Finished Ground Level) in order to be easily maintained. In case that foundations for steel framed buildings are required to be constructed with their top level at a sufficient distance below ground to allow the structural steel base plate and stiffeners to be hidden below ground and to facilitate rainwater pipe details other architectural details, all structural steelwork below ground shall be protected with a durable and structural quality concrete surround. Structural steel column holding down bolt assemblies complete with washer plates and tolerance tubes shall be cast directly into the concrete bases. The site level in the locality of the buildings shall be raised with an adequate depth of suitable imported compacted fill prior to commencement of the foundation works to ensure that no problems are encountered with high water table. Ground floor structures in plant related buildings may generally be of the ground supporting type and construction shall generally consist of compacted sub-base, polythene slip membrane and RC ground slab.
This is subject to
9-48 KHABAT TPP UNITS 1&2 - VOLUME I
proper study and design by the Bidder. Cable and other openings in basements should be above the highest UGWT(Underground Water Table). Level difference of 70 cm is common in this site area. Contraction, expansion and isolation joints shall be provided to control cracking in the concrete caused by early thermal shrinkage strains and seasonal temperature variations. It is recommended that the floor is isolated from all vibratory type machine foundations, building superstructure and perimeter walls. All slabs shall be reinforced top and bottom as a precaution against soft spots in the filled/replaced ground. As a minimum the concrete surface shall be treated with a surface hardener/sealer. A suitable joint sealant shall be applied to all joints. All joints in the ground floor construction shall be capable of carrying shear as necessary to prevent abrupt joints forming. In order to maintain finishes and to support a possible random arrangement of masonry or concrete walls the ground floor structures in office type buildings may require to be provided with suspended RC concrete ground floors supported on RC ground beams, pile caps and piles. Also, in all areas of all building types where external and internal masonry walls are present then a similar suspended RC ground floor construction may be necessary or suitable provision for vertical movement should be made in the masonry to avoid cracking of the masonry.
With regard to the latter alternative, differential
movements at any such joints shall be minimal and shall be visually unobvious. The allowable overall settlement for the building structures shall not exceed 25 mm and the maximum allowable differential settlement for building structures not exceeding 12.5 mm. The overall and differential settlement of foundations for plant shall strictly adhere to the plant manufacturer’s requirements. The general concrete Standard covering the design and construction of the building foundations and ground floors shall be American Concrete Institution (ACI) 318M-08/318RM-08: Metric Building Code Requirements for Structural 9-49 KHABAT TPP UNITS 1&2 - VOLUME I
Concrete and Commentary. Other relevant Standards include: A.
ACI 302.1R “Guide for Concrete Floor and Slab Construction”
B.
ACI 336.2R “Suggested Analysis and Design Procedures for Combined Footings and Mats“
C.
ACI 336.3R “Design and Construction of Drilled Piers”
D.
ACI 349.2R ” Guide to the Concrete Capacity Design (CCD) Method Embedment Design Examples“
E.
ACI 360R “Design of Slabs on Grade”
Later versions of the design codes shall be applicable if available at the time the contract is awarded. If the ground conditions on the specified site consists of poor bearing soils at ground level with possible high concentrations of sulphates and/or chlorides in conjunction with a high water table, the concrete used in foundations and ground floor slabs shall have a minimum 28 day cylinder crushing strength, cement content, cement type, water cement ratio and approved additives sufficient to provide the required durability for the life of the facility. These matters are specified in the concrete section of this Specification. Additional externally applied bituminous barriers shall be provided as necessary. A maximum crack width of 0.3 mm will be incorporated in the design of foundations and ground slabs. Any reinforced concrete (RC) constructions required to retain or exclude liquid and incorporated in the civil works for the buildings shall be designed for a maximum crack width of 0.1 mm in accordance with ACI 224R. 9.4.2.3 Foundations for steam turbines The steam turbine foundations and chimney foundations shall be a monolithic raft supported by piles unless otherwise justified by the Bidder. The bidder shall ensure that the following points are included in the steam turbine foundation works: 9-50 KHABAT TPP UNITS 1&2 - VOLUME I
A.
A minimum rebar content of 80 kg/m3 of concrete shall be provided.
B.
The design of the steam turbine foundations shall satisfy, in addition to an appropriate
internationally
recognized
design
code
on
machine
foundations, the following codes: ACI 351.3R or the relevant international code and standard. ACI 351.3R requires an internal reinforcement cage system which is essential for the foundation to act as a homogenous mass and provide a second line of defence to the machine anchoring system with the holding down bolts and provides guidelines for carrying out dynamic analysis. C.
The turbine foundations shall be isolated from the rest of the works by floor joints.
D.
The ratio of mass of the foundation to weight of the steam turbine plant shall be at least 2.5. The mass of the foundation in this ratio shall mean the mass of the table-top structure where the turbo-generator set is mounted. The steam turbine may be isolated by mechanical springs.
E.
To reduce the risk of dynamic compaction the maximum load on any pile supporting a steam turbine foundation shall not exceed 50% of its working capacity during the normal operating conditions and shall not exceed 85% in extreme conditions. For a foundation supported directly by soil, the same limits apply to the allowable bearing capacity of the soil.
F.
The design of the steam turbine foundations shall include the thermal effects on the foundation and its ability to withstand the extreme differential temperatures likely to be experienced by the foundation, during the construction as well as throughout its design life. Protective measures during construction shall be part of the design. It is a requirement that the design should address a thermal condition due to improper or missing lagging of a maintainable section, such that the supporting structure will not suffer permanent damages due to a small oversight in the maintenance procedure.
G. The section of the steam turbine foundations below ground shall be protected with a coating system to resist attack from the sulphate content in the soils and chlorides from the ground water. Further protection against corrosion of the reinforcement (which leads to expansion of the concrete and cracking) due to the severe chloride ion content of the soils
9-51 KHABAT TPP UNITS 1&2 - VOLUME I
and groundwater shall be provided as covered by the concrete section of this Specification. H.
The steam turbine raft foundations shall be poured in one operation and construction joints are not permitted unless in exceptional circumstances and with the approval of the KNOC. The top decks of the steam turbine foundation shall be similarly poured in a single operation.
I.
The design, detailing and construction of the steam turbine foundations shall allow fully for the “buildability” of the foundations, particularly where congested areas of reinforcement are required.
9.4.2.4 Suspended floors Suspended floors shall be of reinforced concrete (RC) construction, however galvanized open grid type flooring (minimum bars 40 mm x 5 mm at 30 mm c/c) or galvanized chequer type plate flooring (minimum thickness 8 mm) can be used for plant access platforms, access walkways and landings. All open grid and chequer type plate flooring shall be securely clipped to structural supporting beams. Reinforced concrete floors shall be solid but in order to speed construction galvanized steel profiled sheeting may be used as a permanent formwork. The decking shall not be designed in composite action with the concrete slab. A reentrant type trough profile only shall be adopted as described in ASTM A653. All proprietary galvanized edgings and void fillers shall be incorporated into the floor construction.
9.4.2.5 Roofs Structural steelwork framed building other than the gypsum dewatering building and limestone slurry preparation building roofs finished with a profiled, insulated color coated sandwich panel cladding system. And reinforced concrete framed building roofs shall be of reinforced concrete roofs. Access for maintenance purposes shall be provided to all plant and equipment situated on the roofs. This shall be provided by means of suspended steel walkways, stairways and ladders. Access routes shall be obvious and shall exclude the need to walk directly on the steel sheeting. 9.4.2.6 Walls 9-52 KHABAT TPP UNITS 1&2 - VOLUME I
External elevations of all steel framed buildings shall be clad using a suitable plastic coated galvanized steel insulated sheeting system. Cladding to concrete frame buildings shall be in accordance with Architectural requirements. Masonry panel walls shall be used as necessary within the buildings and built in steel posts shall be provided as necessary to provide lateral stability. The design and detailing of all masonry shall be in accordance with ACI 530.1 “Specification for Masonry Structures” and the Uniform Building Code 1997 (UBC). Special reinforcing details set out in the UBC for seismic zone in which the specified site falls shall be adhered to. It should be noted that there are no special construction detailing provisions for seismic zone 1. Occupied rooms shall be provided with fire resistant wall to prevent fire spreading to other rooms. Fire resistant wall shall be designed for 3 hours fire rating. 9.4.2.7 Stairs All common stairs within all building frame types shall be of reinforced concrete construction (unless the common stair is within a fire protected stair well). All stairs within RC buildings shall be of RC construction unless otherwise approved by the KNOC. Stairways within steel framed buildings shall be either of RC or steelwork construction as appropriate. 9.4.2.8 Cranes, monorails and runway beams Generally, permanent lifting facilities are required for plant maintenance purposes for all items of plant where access excludes the use of temporary/mobile facilities and for certain items of plant where the expected maintenance is carried out on a frequent basis. In order to permit the lifting and transfer of major items of plant within the buildings and the removal off-site for maintenance or replacement purposes, overhead electrically operated travelling cranes (EOT), monorails and runway beams will be provided. Each hoisting facility will be designed for the heaviest component, and it will be expected to lift and remove for maintenance. See specific building descriptions for EOT requirements. 9-53 KHABAT TPP UNITS 1&2 - VOLUME I
The hoisting facilities required are detailed in the mechanical specification Section 6. All crane rails shall be provided as specified by the lifting equipment manufacturer/Bidder. 9.4.3
Materials All materials shall conform to the latest edition of the relevant American or International Standards cited within this Specification and within the design Standards referred to therein. Any materials not fully specified and for which there is not a relevant Standard shall be the best of their kind. For materials not fully specified, provisions of respective manufacturer’s catalogues and test reports should be provided for approval along with material samples. Samples of all materials for the Works may be called for at any time by the KNOC and shall be furnished by the Bidder free of charge and without delay. The cost of all routine tests required by the relevant American or other International Standards shall be borne by the Bidder.
9.4.4
Civil design parameters
9.4.4.1 Design methodology The Bidder shall adopt a design methodology which will identify all significant factors in the design and ensure that proper attention is given to each factor at every stage in the design process. A.
Foundation design concept
B.
Loading conditions 1) Dead 2) Superimposed 3) Plant and equipment 4) Wind 5) Seismic 6) Thermal 7) Electric overhead travelling (EOT) cranes 8) Mono rails/runway beams
9-54 KHABAT TPP UNITS 1&2 - VOLUME I
C.
Load combinations 1) In accordance with ASCE 7-05, Minimum Design Loads for Buildings and Other Structures and UBC 97
D.
Steel structure design parameters 1) Design concept fixed, pinned, portal, braced
E.
Concrete structure design parameter 1) Design concept braced, unbraced, slender, short, shear walls, etc.
F.
Concrete 1) Grade 2) Cover
G. Reinforcement 1) Types The Design Basis Statement shall also clearly state the American Standards or Internationally recognized Codes to be used for design and material specification applicable to the entire scope of civil works for the Contract. The Bidder shall also prepare for the whole of the works and each discrete section thereof, Detailed Design Reports for submission in accordance with the Contract. To allow the KNOC adequate time to plan and complete review cycles of the various reports, the Bidder shall prepare and issue a timetable and register of the submittals required to fulfill the Contract. The Detailed Design Reports shall be set out under the following subsections: 1) Scope of design 2) Design criteria 3) References 4) Materials and properties 5) Loads 6) Load Combinations 7) Analysis and design 8) Discussion and conclusions 9-55 KHABAT TPP UNITS 1&2 - VOLUME I
9) Appendices
9.4.4.2 Loading The following loads shall be considered in design. Where relevant, the appropriate Codes and basic design parameters are also given below: A.
Dead - in accordance with ASCE 7-05 “Minimum Design Loads for Buildings and Other Structures” or the relevant international code and standard.
B.
Imposed - in accordance with ASCE 7-05 “Minimum Design Loads for Buildings and Other Structures”. The Bidder shall determine the correct superimposed loading for all floor areas but a minimum superimposed floor load of not less than 5 kN/m2 shall apply to all plant related buildings. The Bidder shall determine the correct superimposed loading for all roof areas but a minimum superimposed roof load of 1 kN/m2 shall apply to roofs where no access other than maintenance is required and a minimum superimposed roof load of 1.5 kN/m2 shall apply to roofs where access is provided.
C.
Wind - In accordance with ASCE 7-05 “Minimum Design Loads for Buildings and Other Structures”. The basic wind speed for the specified site shall be determined by the Bidder, but shall not be less than 45 m/sec (This is a 3 second gust speed at 10 m above ground in Exposure C conditions, associated with an annual probability of occurrence of 0.02). Exposure category D shall be used in the design. This applies also to storage tanks.
D.
Seismic – All structures including buildings and their foundations shall be designed for seismic events as defined in the “Uniform Building Code” Zone 3.
E.
Thermal - The Bidder shall be responsible for determining the correct thermal range for design purposes but the thermal range shall be not less than -10°C to +55°C taken as ±40°C for design purposes when assessing building movements and shall be not less than ±35°C when considering strength design. As many facilities are the outdoor type the design has to take into consideration of a black object under direct sunshine can attain a temperature of 75°C.
9-56 KHABAT TPP UNITS 1&2 - VOLUME I
F.
EOT Cranes - The loadings for EOT cranes shall be supplied by the crane manufacturer. Allowance shall be made in the design for dynamic affects, transverse surge, longitudinal surge and crabbing (if applicable). Design load combinations shall be in accordance with AISE Technical Report No. 13 or AISC Steeel Design Guide 7. The allowable vertical deflection of a crane gantry girder based on maximum static wheel loads shall not exceed span/600. The allowable horizontal deflection of a crane gantry girder due to transverse crane surge shall not exceed span/500 (based on top flange properties only).
G. Mono-rails/runway beams - Generally, permanent lifting facilities are required for plant maintenance purposes for all items of plant where access excludes the use of temporary/mobile facilities and for certain items of plant where the expected maintenance is carried out on a frequent basis. All mono-rails and runway beams shall be designed to AISE Technical Report No. 13 or AISC Steel Design Guide 7. Lifting blocks of 1 tonne capacity and over will be electrically operated. H.
Major pipework loads - plant specific load.
I.
Global pipework loads - plant specific load.
J.
Cables - plant specific load.
K.
Plant loads - plant specific load.
L.
Erection loading - plant specific load.
M. Installation loading - plant specific load. N.
Maintenance loading - plant specific load.
O. Miscellaneous maintenance/access platform loads - plant specific load. N.B: Fifty (50) years return period values shall be used for environmental loading as appropriate.
9.4.4.3 Foundations and earthworks Design and construction of foundations and earthworks shall be in accordance with the requirements set down in the following: NAVFAC DM-7.2: Foundations and Earth Structures ACI 351.2R: Foundations for Static Equipment
9-57 KHABAT TPP UNITS 1&2 - VOLUME I
ACI 351.3R: Foundations for Dynamic Equipment ASTM Standards applicable to earthworks materials and testing. In addition the Specification for Piling and Embedded Retaining Walls, published by the Institution of Civil Engineers (ICE) shall be followed. The Bidder shall state in his calculations the maximum permissible foundation movement that may be tolerated consistent with normal operation of the plant. The design of the foundations for the steam turbines and other plant foundations subject to dynamic loads shall be in accordance with ACI 351.3R “Foundations for Dynamic Equipment” or the relevant international codes and standards. All other plant foundations and building foundations shall be designed in accordance with the relevant American Standards or the relevant international codes and standards. In the design of plant foundations, due account should be taken of settlement criteria required by plant manufacturers. Foundations shall be designed with a factor of safety of three (3) against bearing capacity failure of the subsoil and a factor of safety of two (2) against overturning and sliding unless otherwise agreed or instructed by the KNOC. For normal loads, the foundation designs shall be based on a stress distribution of 100% compression on the underside of the base (eccentricity of loading < L/6) and within the allowable bearing capacity of the soil. For foundations with overturning moments, the following shall be satisfied: A.
Uniaxial bending: eccentricity < L/4
B.
Biaxial bending: 70% of the base area to be effective in compression
C.
Allowable bearing capacity of the soil not to be exceeded.
9.4.4.4 Structural design standards 9-58 KHABAT TPP UNITS 1&2 - VOLUME I
The following Standards shall apply as appropriate: A.
AISC: Manual of Steel Construction - Allowable Stress Design - 9th edition
B.
ACI 318M-08/318RM: Metric Building Code Requirements for Structural Concrete and Commentary
C.
Uniform Building Code (UBC) 1997
D.
ASCE 7-05: Minimum Design Loads for Buildings and other structures
E.
National Structural Steelwork Specification for Building Construction
F.
AISE Technical Report No. 13: Guide for the Design and Construction of Mill Building
G. SSPC A: Good Painting Practice Steel Structures Painting Manual Volumn 1 H.
ASTM
A 123: Standard Specification for Zinc(Hot-dip Galvanized)
Coatings on Iron asn Steel Products
9.4.4.5 Security provisions The Bidder shall fence off the site and take all reasonable precautions to safeguard the health and safety of all persons, whether or not they are his employees, from all construction and construction related activities. The Bidder’s proposals for security shall be submitted to the KNOC. The exact delineation of the Bidders Site shall be established and agreed with the KNOC prior to the commencement of the Works. Foundations for security and checkpoint installations shall be suitably designed against forced entries by motor vehicles. The bidder shall provide the security provisions to reflect the requirements of the National Standard to ensure no disruption to the safe operation of the power plant. For general site security, surveillance and alarm alert requirements see also Section 8 of the Specification. 9.4.4.6 Roads and hardstandings New hardstandings and access roads serving the proposed plant shall be integrated into the existing road network. The new permanent road system within the site shall be designed to allow for adequate access and emergency situations during operation and maintenance. The layout of the access roads and pavings serving the Plant including the Water Treatment Plant and Chemical Storage Tanks, etc., shall be designed to allow safe manoeuvrability 9-59 KHABAT TPP UNITS 1&2 - VOLUME I
and hardstanding for all necessary deliveries. All existing roadways and accesses to and within the site shall be repaired to the state that they were in prior to the works commencing. Temporary roads during construction period are to be suitable for transporting and positioning plant and equipment. Permanent roads shall be designed in accordance with Iraqi Ministry of Public Works and AASHTO/ASTM requirements, e.g., Guide for Design of Pavement Structures published by AASHTO, on the basis of a 25 year life. The Bidder shall supply justification for the number of standard axles to be used in the design. The Site speed limit shall be 10 mph (15 km/h). The roads within the site areas shall be constructed between raised kerbs and graded to falls leading surface water into gullies or catchpits which will connect into the main drainage system. Main road construction shall typically be of crushed rock sub-base on compacted subgrade appropriate to the ground conditions, with Asphaltic Concrete paving, or concrete, wearing course as appropriate. Concrete paving shall be provided where oil or chemical spillages may occur. The Bidder shall supply justification for his design proposal to the KNOC prior to construction of any roads or hardstandings. Major access roads shall be 7.3 m wide and shall include the necessary kerbs, drainage, road markings and signs. Radii shall be provided on turning areas and corners which are suitable for transporting heavy equipment and plant during the construction period as well as for all future maintenance needs. Road markings and signs shall be in accordance with the requirements of the Ministry of Public Works Administration. Footpaths shall be of 1500 mm nominal width at minimum and designed for an accidental wheel load of 100 kN where footpath is adjacent to the roadway and 20 KN when located away from roadways. Footpaths shall be either precast concrete flags or asphaltic concrete paving. Within the plant area height limit gauges shall be provided where height 9-60 KHABAT TPP UNITS 1&2 - VOLUME I
clearances are limited and in particular where there is danger from overhead lines. Safety barriers shall be provided where there are exceptional local hazards or where specific plant protection is required. These barriers will be of the Armco or substantial bollard type and be removable. Car parks (other than those provided for overflow) shall be constructed to the same specification as permanent roads with the additional requirements specified below. A minimum permanent parking capacity of 80 passenger vehicles shall be provided with a further 50 spaces available as an overflow car park. Temporary car parking shall also be provided during the construction period of sufficient capacity to cater for the workforce to be employed.
All
temporary car parking areas shall be provided with temporary sunshades and the final car park spacing shall be provided with permanent sunshades. The surface of the hardstanding shall be laid with falls to the drainage system. Care shall be taken during the construction that no materials enter the drainage system. At the junction of the hardstanding and roads due to different thickness of foundations, precautions shall be taken to ensure that sub-surface drainage from the hardstanding does not have a detrimental affect upon the road foundations. The Bidder shall take reasonable steps to maintain the free movement of traffic on any roads used by him to gain access to the Site. All roads shall be maintained free of any spillage from the Bidder’s vehicles. The Bidder shall provide for all roads within the site as well as any access roads required both for temporary and permanent use. The access roads shall be properly connected to the existing roads on or outside the site boundary. Temporary access roads of adequate standard shall be provided for site traffic of all bidders pending completion of the permanent road construction up to and including binder course.
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Permanent access roads shall be provided from the main site roads to all plant and buildings. They shall be of suitable width and radius for the proper movement, installation and maintenance of plant. Hardstanding areas around the outdoor auxiliary plant etc may be constructed from Asphaltic Concrete Paving, or Concrete, laid to falls leading storm water to gullies or catchpits. Hardstanding around all chemical, fuel handling/storage areas/delivery areas shall be concrete slabs with suitable gully drains leading to oil interceptors or chemical tanks as appropriate. Where required gravel areas shall consist of a 150 mm layer of 20 mm gravel on a geotextile membrane overlaying a compacted formation. 9.4.4.7 Drainage The Bidder shall install the following drainage systems: A.
surface water drainage
B.
sewage water drainage
C.
oil/water drainage
D.
chemical waste water drainage.
General The surface water and sewage drainage systems shall be designed and constructed in accordance with the requirements of the related international standards. Surface water that is contaminated with fuel or oil shall be sufficiently treated prior to disposal. The system shall be designed for the maximum predicted coincident flows from the various sources of plant effluent. A schedule of plant effluents shall be prepared at the design stage by the Bidder indicating the source and type of effluent, peak and average flow rates and coincident flows under all conditions of normal operation, maintenance and emergencies. Contaminated effluent shall receive appropriate treatment at the source of 9-62 KHABAT TPP UNITS 1&2 - VOLUME I
pollution before being collected and discharged to a drainage system or the river/sea. Facilities shall include for oil separation, chemical treatment and neutralization as appropriate. Permission to discharge to that system shall be obtained from the appropriate authority. Provision shall be made for the disposal of any effluents that cannot be treated satisfactorily. Every effort shall be taken to ensure that the risk of pollution is minimized. Provisions shall be made to bund all storage and all delivery areas shall have a suitable drainage gully to all sides to prevent spillages spreading to the surrounding ground. The quality and type of pipe used in carrying plant effluent shall be adequate to resist any resulting corrosion. The use of gravity drainage shall be maximized. However, pumping may be necessary over part of the system to raise invert level, provide a more economical alternative to deep construction works for long pipe runs or for final discharge elevation. The Bidder shall incorporate and detail lift chambers (pumps) into the drainage systems as appropriate. Gradients in gravity pipelines shall be kept above the minimum recommended limits for given pipe sizes so as to ensure above minimum velocities and pipe self cleaning, thus reducing the potential for sedimentation within the drainage systems. The upper layers of the site are composed of loose material that is prone to settlement. The Bidder shall ensure that pipe runs do not develop “backflows” due to settlement along their length, by making suitable allowance for differences in invert level between the start and end of any given pipe run e.g., between manholes, catch-pits, etc. Where existing redundant drainage interferes with the new works for the power plant it will either be removed, or where this is impracticable it shall be filled with suitable material to prevent structural deterioration, unauthorized use, ingress of ground water, infestation of rodents, etc. Surface water drainage 9-63 KHABAT TPP UNITS 1&2 - VOLUME I
The Bidder shall design and install a surface water drainage system that will effectively drain the site and discharge to an existing public storm water system or a designated soakaway agreed in advance with the KNOC. Before discharging into the outside system or river/sea, the surface water shall pass through an oil/water separator. The discharge from the oil/water separator shall contain no visible oil or grease, i.e., less than 10 ppm. The capacity of the surface water drainage system shall be designed based upon a Design Storm Frequency of 1 in 10 years and Design Flooding Frequency of 50 years, or other criteria required by the Iraqi Local Authority regulations. The bidder shall pay special attention to the impact on the site drainage resulting from high intensity, short duration rainfall events which are known to occur. The size of the pipeline systems shall be designed in accordance with the Wallingford Procedure, or similar equivalent. The Bidder shall install a “cut-off” drain at the boundary if the terrain is likely to produce flooding to the power plant area. Catchpits shall be provided in the surface water drainage systems in areas where a high proportion of suspended material could occur in the run-off. In such cases the invert of the catchpit shall be at least 500 mm below the invert of the outlet pipe, increasing in depth with increased pipe diameter. The plan area of the catchpit shall be sufficiently large to reduce the velocity of the flow to allow solids to be deposited. The design of the pipeworks shall be in accordance with the pipe manufacturer’s recommendations in respect of pipe grade, trench dimensions and pipe bedding and protection using the Simplified Tables of External Loads on Buried Pipelines, published by the Road Research Laboratories of the Department of Transport. The surface water drainage system for roofs and paved areas shall be designed in accordance with the international standards or similar American or Iraqi Standard.
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Side entry gullies shall be used for roads and horizontal gullies for parking and paved areas and the system should be designed for removal of trapped sand. Roof drainage shall be collected via roof outlets and downpipes to gullies or inspection chambers at ground level prior to discharge to the main drainage system. Manhole and chamber covers shall be heavy duty throughout. Sewage water drainage The design of the sewage water drainage system shall be in accordance with the international standards or similar American or Iraq Standards, and shall be based on the number of permanent members of staff. The new drainage works shall be fully designed and constructed and shall be independent of any systems on the specified Power plant site. Sewage water shall be treated by a proprietary sewage treatment plant. Treated discharge from the plant shall meet the requirements of the responsible Iraq Authority, before being discharged to a public sewage drainage system or the river. Oily water drainage Oily water drainage systems shall be provided for, but not limited to, the following areas:
Oil unloading areas adjacent to oil storage;
Oil and fuel storage compound drainage;
Oil filed transformer compounds;
Car parking areas;
Plant and equipment from which oil spillages could occur.
The Bidder shall design and install an oily waste water drainage system which will effectively drain all areas where oil spillages could occur. The design shall incorporate bunded areas, oil interceptors and traps. The quality of the effluent shall be acceptable in all respects to the Local Authority. 9-65 KHABAT TPP UNITS 1&2 - VOLUME I
Bunds provided in transformer compounds, oil storage areas, lube oil tanks and such like shall have an impounding capacity 1.25 times the largest possible oil spillage that could occur. The Bidder shall provide adequate facilities for the inspection and maintenance of oil interception equipment. The oil interceptor shall be of adequate size to cater for an accidental total spillage of the largest transformer on site. Chemical waste water drainage The system shall be designed for the maximum predicted coincident flows from all sources of plant effluent. The Bidder shall prepare a schedule of plant effluents indicating the source and type of effluent, the peak and average flow rates and coincident flows under all conditions of normal operation, maintenance and emergencies. The contaminated effluent shall receive the appropriate treatment before it is discharged. The pipeworks, fittings, etc., shall be fully designed and use the most appropriate materials to withstand the chemical composition and temperatures of the effluents.
9.4.4.8 Buried pressure pipelines Buried pressure pipelines for water mains, fire water mains and rising mains for drainage shall be designed in accordance with similar American or Iraqi Standards. All pipelines carrying fuel oils shall be installed in sealed ducts to prevent ground contamination in the event of a pipework leak.
9.4.4.9 Buried services Ducts and chambers for electrical, mechanical and telecommunication services shall be designed to the appropriate loading. 9-66 KHABAT TPP UNITS 1&2 - VOLUME I
Chambers shall incorporate a drainage sump. Where practicable the sump shall be linked to the appropriate drainage system. The Bidder shall allow for the relocation of any existing buried services. 9.4.4.10 Protection of structural steelwork The following is indicative of the type of corrosion protection
surface
preparation and painting: Main and secondary steelworks are in accordance with Section 9.6 of this Specification. Cladding rails and roof purlins Hot dip galvanized fixed with spun(all areas) galvanized or sherardized bolts or alternatively in accordance with Section 9.6 of this Specification Where fire protection is required this shall be by an intumescent paint system in exposed situations (subject to required fire rating being achievable) or, where concealed, a fire resistant board system will be acceptable. 9.4.4.11 River works Any works, such as those associated with the surface water or sewage water discharge outfalls that may affect or be affected by the river environment shall be designed in accordance with similar American or Iraqi Standards. 9.5
Specific Building and Architectural Requirements
9.5.1
Cladding and decking
9.5.1.1 General Notwithstanding the following outline Specifications, cladding and roof decking shall be chosen, designed, detailed and constructed to achieve the thermal and acoustic requirements for the plant and building operation and the air and vapour movement requirements for the total building fabric. The design of the individual buildings and their relationship to each other shall take account of the requirements for compliance with the relevant sections of the fire legislation in force in Iraq. 9-67 KHABAT TPP UNITS 1&2 - VOLUME I
The Bidder shall complete the design of the cladding system in accordance with the relevant codes of practice and insurers requirements, and coordinate the design and detailing of the cladding system with all related works. The external fabric of the building is required to give a durable, economical and easily maintainable form of construction which is responsive to the prevailing weather conditions. Due consideration shall be given to the durability against erosion by sand storms and blocking up of the services by trapped sand. The building fabric shall ensure that environmental conditions within the buildings can be maintained within the prescribed limits with the minimum energy use to fully comply with building legislation. Very high surface temperatures can be experienced on all faces of the buildings. Because of the high insulation value of the wall and roof construction which will not allow a high heat transfer to the inside of the building from the external surface of the panels, all wall and roof finishes shall be light coloured with high reflective values to minimize the build up of surface temperatures on the external face of the panels. The panel system proposed therefore shall have test certificates to prove that it has been tested to the maximum surface temperatures which are likely to be experienced at site without any delamination or deterioration affects on the panels or their joints over the required lifetime of the building. The wall and roof cladding shall be designed and installed to comply with the manufacturer’s requirements to obtain a 25 years guarantee on the completed roofing and walling. 9.5.1.2 Metal wall cladding Wall cladding shall consist of factory manufactured sandwich panels with a minimum 0.5 mm thick external sheet and a 0.4 mm thick inner sheet. The void between the sheets shall be fully filled as part of the manufacturing process with CFC free rigid polyurethane insulation fully bonded to the inner surfaces of the outer and inner sheets.
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The panels to be used shall have a profile approved by the KNOC. The panels shall be manufactured to external and internal colours approved by the KNOC. The external and internal panel finishes shall be selected to achieve the specified guaranteed life expectancy. All flashings, trims, cappings, etc., shall have the same finish as the panels. All cladding should be resistant to ultraviolet degradation and all colour coatings should have a high fade resistance. The panels shall be of a design for secret fixing. The inner face of the sandwich panels shall act as the vapour barrier. A full seal shall be provided between all panels in accordance with the manufacturers instructions to achieve continuity of the vapour barrier. The vapour barrier shall be integrated with, continuous, and sealed to the vapour barrier in the roof system, the plinth wall and all components built into the fabric of the building. The wall cladding system shall achieve a ‘U’ value of 0.25 W/m2K or better, based on an aged thermal conductivity of 0.020 W/mK, and a minimum 80 mm thickness of insulation shall be used. The detailing of all junctions and interfaces shall ensure that there is continuity of the insulation value across the whole exterior of the building. Allowance shall be made for the provision of spacers at fixing points to achieve a true line in the sandwich panels. 9.5.1.3 Metal roof cladding Roof cladding shall consist of factory manufactured sandwich panels with a minimum 0.5 mm thick external sheet and a 0.4 mm thick inner sheet. The void between the sheets shall be fully filled as part of the manufacturing process with CFC free rigid polyurethane insulation fully bonded to the inner surfaces of the outer and inner sheets. The panels to be used shall have a profile approved by the KNOC. The panels shall be manufactured to external and internal colours approved by the KNOC. The external and internal panel finishes shall be selected to achieve the 9-69 KHABAT TPP UNITS 1&2 - VOLUME I
specified guaranteed life expectancy. All flashings, trims, cappings, etc., shall have the same finish as the panels. All roof cladding should be resistant to ultra-violet degradation and all colour coatings should have a high fade resistance. The panels shall be of a design for secret fixing. Wherever possible, the sandwich panel shall be in a single length from ridge to eaves except where interrupted by a roof ventilator or other penetration. The inner face of the sandwich panels shall act as the vapour barrier, and require to be fully sealed between panels in accordance with the manufacturer’s instructions to achieve continuity of the vapour barrier. The vapour barrier shall be integrated with, continuous, and sealed to the vapour barrier in the wall system and all components built into the fabric of the building. Anti condensation tape shall be provided where recommended by the manufacturer. The roof cladding system shall achieve a ‘U’ value of 0.25 W/m2K or better, based on an aged thermal conductivity of 0.020 W/mK, and a minimum 80 mm thickness of insulation shall be used. The detailing of all junctions and interfaces shall ensure that there is continuity of the insulation value across the whole roof and its junctions with the walls and any built in components. Where rainwater gutters form part of the roof covering, they shall be fully sealed and have the same U value as the remainder of the roof. The design of the roof structures, finishes and accessories shall ensure that deposits of wind blown sand and dust, which can build up on roof areas behind parapets and projections through the roof, can be dealt with, and all rainwater pipe connections shall be easily accessible to allow them to be cleaned. 9.5.1.4 Support for cladding Before the installation of roof and wall panels, the bearings shall be checked to ensure they are straight and to an even and correct line and gradient. Adjustment shall be made where necessary to ensure consistency of line and 9-70 KHABAT TPP UNITS 1&2 - VOLUME I
continuity of support, and spacers shall be utilized to ensure the correct alignment and bearing is achieved where adjustment of the main support cannot be achieved. 9.5.1.5 Fixings The panels shall be fixed to steel support beams with threaded type, grade 304 austenitic stainless steel, self tapping screws in a manner recommended by the manufacturer. The complete fixing screw shall be stainless steel. All wall and roof panels shall have secret fixings. Fixings for flashings, trims, etc., shall be complete with or shall have integral color matched caps or heads. Fixing of sheeting, flashings and cappings, etc., shall be by self drilling or self tapping stainless steel screws of size recommended by the manufacturer. Fixing of brackets, straps etc. to cappings shall be by stainless steel screws, with countersunk heads where appropriate. Additional fixings, saddle washers and cover caps shall be provided if deemed necessary where high suction loads can be experienced. The whole of the works shall be carried out in accordance with the relevant international code and standard and shall provide a completely weathertight enclosure. 9.5.1.6 Flashings All external flashings shall be formed from a minimum 0.7 mm thick metal, and shall be fully weather sealed at all edges. All flashing, trims and sills associated with wall and roof cladding shall be the same colour as the cladding to which they are fixed. All flashings, trims, cappings, etc., shall have the same finish as the panels. External flashings shall be detailed, installed and fully sealed to fully close off any potential air, noise or water transmission path. Internal flashings and trims shall be detailed and sealed to maintain the integrity of the vapour barrier. Prior to the installation of the second side flashing or trim, the space between inner and outer flashings shall be fully filled with insulation to maintain the same insulation value as the walls and roof. 9-71 KHABAT TPP UNITS 1&2 - VOLUME I
9.5.1.7 Caulking compound and sealing strip/gaskets All sealants of whatever form shall be to the recommendations of the cladding manufacturer, and they shall be located and installed in accordance with their instructions. Separation strips between panels and substrate shall be provided in accordance with the panel manufacturers recommendations. 9.5.1.8 Panel glazing Glazing panels of the same profile as the sheeting may be incorporated into the wall and roof cladding. Where these are specified, they shall be double glazed and meet the requirement of Fire Codes, to ensure that the fire rating and structural requirements are maintained. 9.5.1.9 Windows Windows incorporated into the external wall cladding shall be of a colour approved by the KNOC. They shall comply with the relevant international code and standard. All window frames shall incorporate a thermal break and internal voids in the frames shall be filled with insulation to prevent heat transfer. Windows shall achieve a ‘U’ value of 0.45 W/m2K or better. Windows shall be complete with all flashings and shall be fully sealed to substrate. The vapour barrier shall be fully sealed to the windows. All windows shall be glazed with solar reflective glass with a low heat transfer value in double glazed units. The windows installed at the fire resistant wall shall take account of fire resistance and natural lighting requirement.
9.5.1.10 Solar shading All glazed areas which can be subject to direct sunlight at any time of the day throughout the year shall be provided with external shading. Areas of both horizontal and vertical shading shall be provided to cope with the angle of the sun anywhere on its path. Solar shading shall be formed by a fixed system. 9.5.1.11 Louvres 9-72 KHABAT TPP UNITS 1&2 - VOLUME I
All external louvres built into the external cladding shall have an in-built sand trap, and the louvre frame shall be fully sealed to the surrounding construction. 9.5.1.12 Safety systems Adequate means of access shall be provided to the roof of buildings for maintenance of any equipment located there. Where access is provided, either parapets or a full safety system shall be installed for the protection of maintenance personnel. Any safety system provided shall be fixed in such a way that it does not reduce the integrity of the roof finish. 9.5.1.13 Roof drainage The roof drainage system shall be designed and detailed to cope with the calculated maximum rain requirement. Where rainwater gutters form part of the roof covering, they shall be fully sealed and have the same U value as the remainder of the roof. Supports for the rainwater gutter shall be fully integrated with the roof and wall cladding. Rainwater pipes shall be aluminium or galvanized mild steel, medium gauge to the relevant international code and standard. Rainwater pipes for the steam turbine building and central control building shall be routed internally, but the other buildings shall be routed externally. Pipes shall generally be straight and plumb fixed with brackets to structural steel columns. They shall be complete with suitable bends for connection to outlets and to drainage. Jointing compound where required shall be to approval. Inspection covers shall be provided and suitably sealed, to all pipes immediately above ground floor level. 9.5.1.14 Movement The design, detailing and fixing of the roof and wall cladding, and all trims, cappings and flashings shall make allowance for the calculated movement of the building and cladding due to wind loads and thermal expansion and contraction. Allowance shall be made for movement across the whole structure, fabric and finishes of the buildings to cope with the calculated maximum thermal movement of all the elements of the buildings. This shall also be considered in conjunction with the calculated maximum structural movement due to wind loading. 9-73 KHABAT TPP UNITS 1&2 - VOLUME I
Allowance shall also be made for the movement of elements of the construction which will require joints at closer centres as required by the relevant codes of practice. 9.5.1.15 Standards The panels shall have a Class 0 surface, in accordance with the relevant international code and standard., and roof panels shall be rated AA when tested to the relevant international code and standard. The roof and wall cladding systems shall be designed in accordance with the relevant international code and standard. Calculations shall be provided to prove the adequacy of the roof and wall cladding, its complete support systems and all fixings. 9.5.1.16 Acoustic requirements Specific requirements are stated for the maximum increase in noise levels from the completed buildings and these shall be taken into account in the design and detailing of the cladding and roof systems to ensure that the target noise levels are achieved. 9.5.1.17 Cutting If hole cutting is required on site to accommodate penetrations, this shall be done using a motorized disc cutter and/or hole saw or nibbler. Acetylene cutting shall not be allowed. Suitable flashings of material and finish to match the main sheeting or, where appropriate, soaker sheets shall be provided incorporating welded upstands, etc.
9.5.1.18 Verification of performance The Bidder shall submit evidence and calculations demonstrating compliance of the design with performance requirements before commencing fabrication of any part of the cladding. All submitted information shall be based on approved laboratory testing or computer modeling. 9.5.1.19 Product delivery, storage and handling All cladding components shall be protected, transported and handled in accordance with the manufacturer’s instructions, to avoid damage by distortion 9-74 KHABAT TPP UNITS 1&2 - VOLUME I
or by impact damage to finishes. Bundles shall be lifted using ropes or chains with slings positioned correctly to minimize pressure/distortion across or along the sheets. When removing individual sheets from bundles they shall be lifted directly and not dragged. 9.5.1.20 Detail drawings The Bidder shall submit detail drawings of the work in this section for approval by the KNOC. These drawings shall include complete scale and full size details of all cladding components, showing the relationship to and integration with adjacent building elements, the points to which dimensions are taken and all fixing proposals. 9.5.2
Metal doors and frames Fire resisting internal and external metal doors and frames shall be constructed from galvanized steel conforming to the relevant international code and standard and criteria for the fire resistance of elements of building construction. The fire rating shall be 2 hours, and the Bidder shall provide evidence of this performance by test certificate or assessment by an approved authority to the KNOC before manufacture. And the fire resisting doors that fire rating 2 hours Include 20 minutes insulation shall be placed only along escape routes to protect employees (and public) from injury. All external door frames shall incorporate a thermal break and internal voids in the frames shall be filled with insulation to prevent heat transfer across the frames. All door frames shall also incorporate spacers at the fixing points to prevent distortion. All doors shall be complete with ironmongery including stainless steel hinges, handles, bolts, closers, locking arrangements, and where appropriate emergency escape facilities. Locking shall adopt a Site Master Key system to be agreed with the KNOC. Doors provided solely as a means of escape shall be fitted with panic bars and shall not be openable from the outside. Reinforcement of the metal shall be provided at all fixing points for 9-75 KHABAT TPP UNITS 1&2 - VOLUME I
ironmongery on the doors and frames. Personnel doors shall be to approval. Hinges shall be stainless steel. Roller shutter doors shall be electrically operated with manual override, automatic stop facility and automatic closing facilities where fire resistance is required. They shall be provided by an approved Bidder. All external doors shall achieve at least the same acoustic requirements as for the walls. All external doors including roller shutter doors shall achieve a ‘U’ value of 0.45 W/m2K or better. The junction of the door frames with the surrounding wall shall be detailed to eliminate any potential noise, vapour or fire path. All exposed surfaces of doors, frames and trims shall be shop primed and painted on site. The Bidder shall submit to the KNOC, for his approval before manufacture, copies of drawings showing construction of doors and frames and their junction with surrounding wall construction. Doors and frames shall be protected from distortion during transit, handling and storage. Doors and frames shall be provided with protective coverings which shall be retained in position for as long as possible.
9.5.3
Internal doors and frames If agreed with the KNOC that internal doors and frames should not be metal, they shall be of an approved hardwood. Unless otherwise specified, the frames shall be screwed and pelleted to pallets or wedged and screwed and pelleted to grounds. Architraves and stops shall be hardwood with mitred joints. A seal shall be provided between the architrave and surrounding wall. 9-76 KHABAT TPP UNITS 1&2 - VOLUME I
The doors shall have fire resistance in accordance with International Building Code 2000. Architraves shall not be fixed until after the wall finish has been formed unless otherwise specified. Vision panels shall be incorporated into fire doors with hardwood beads detailed so as not to compromise the required level of fire rating. Glazing shall be to the requirements International Building Code 2000. All doors and frames shall be to the approval of the KNOC. Where these are required to be fire resisting, the combined door/frame construction shall provide the necessary fire rating when tested to the relevant international code and standard. A certificate of compliance shall be provided by the manufacturer and submitted to the KNOC by the Bidder. Fire resisting doorsets shall be installed in a manner to ensure continuity of the fire resistance between the frame and the surrounding fire wall. The junction of the door frames with the surrounding wall shall be detailed to eliminate any potential noise, vapour or fire path. All doorsets shall be complete with ironmongery including stainless steel hinges, bolts, locking arrangements, closers, handles and where appropriate, emergency escape facilities. Locking shall accord with the Site Master Key system to be agreed with the KNOC. All doors shall include blockings for the fixing of ironmongery. Doorsets shall be kept under waterproof cover during transit and be stored on Site in dry protected conditions. They shall be handled and stacked carefully to avoid distortion or damage. Protective coverings shall be retained in position for as long as possible. 9.5.4
Internal vision panels Vision panels in internal masonry walls shall be of a design to match the doorsets in the relevant room. Where appropriate the fire rating shall be the same as that of the wall in which they are situated and glazing shall comply with the requirements of Regulations for the location of the vision panel. 9-77 KHABAT TPP UNITS 1&2 - VOLUME I
9.5.5
External walling The materials shall be selected for durability and low maintenance characteristics. In selecting the materials, resistance to site environmental conditions shall be considered. The appearance of the building shall be carefully considered to form a pleasing yet functional arrangement. The buildings, including administration building, operations & maintenance management building shall have a high standard of architectural design to use like composite external wall construction with locally available or preferred materials. Steam turbine building is to be constructed with an external plinth wall a minimum height of 1.2 meters above ground level. The exact height shall be determined to suit the external architectural treatment of the buildings and the requirements of the plant layout internally. The design of the wall shall incorporate insulation to achieve the same U value as the remainder of the external wall, and a vapour barrier shall be provided which is integral with the vapour barrier of the surrounding construction. The complete construction of external walls shall have a ‘U’ value of 0.25 W/m2K or better. The wall must incorporate a damp proof course which is bonded to the damp proof membrane in the floor construction. The plinth wall shall include all necessary stabilizing measures to satisfy structural requirements. The external finish of the plinth wall shall be agreed and an appropriate specification shall be submitted for comment/approval by the KNOC. The Bidder shall submit to the KNOC details of the proposed design of the walling and its junctions with all surrounding elements. The design and detailing of the plinth wall shall take account of noise level requirements to ensure that the target noise levels are achieved. Details of 9-78 KHABAT TPP UNITS 1&2 - VOLUME I
OSHA Section 1910.95 “Occupational Noise Exposure” shall be followed to establish the maximum permissible noise levels. Generally, architectural methods shall be applied for effective noise control, such as: A.
Suitable noise absorbing materials shall enclose the high noise mechanical equipment ; concrete block enclosure wall, acoustic mineral textile ceiling and solid concrete floor with finish.
B.
Selected housed steel springs, ribbed neoprene, or precompressed glass fiber materials shall be used to support vibratory equipment.
Occupied rooms shall be provided with fire resistant wall to prevent fire spreading to other rooms. Fire resistant wall shall be designed for 3 hours fire rating. 9.5.6
Internal masonry walling Internal masonry walls shall be constructed in dense concrete blocks. These shall be fairface blocks built fairface where exposed in final construction. The blockwork shall be finished with two coats plaster and painted, in all areas with suspended ceilings, and the remainder shall be fairfaced, sealed and painted. Necessary measures shall to be taken to ensure structural stability of free standing masonry walls. Vision panels shall be provided in masonry walls where they are required to satisfy operational requirements. In office areas, the blockwork shall be provided full height, or to minimum of 150 mm above the false ceiling where one is provided, on the external walls, and finished to match other internal walls in office areas. The Bidder shall submit for approval all details of blockwork to be used on the project. Occupied rooms shall be provided with fire resistant wall to prevent fire spreading to other rooms. Fire resistant wall shall be designed for 3 hours fire rating.
9.5.7
Cement rendering Cement rendering shall be applied to exterior masonry, exterior concrete 9-79 KHABAT TPP UNITS 1&2 - VOLUME I
surfaces, eaves and balcony soffits, wall bases above concrete floors and over tiled areas of Sanitary Rooms as indicated on the drawings. Cement rendering shall be applied in three coats producing a minimum total thickness of 20 mm having a course, granular finish texture except where required on interior work which shall be trowelled to a smooth, dense finish. Cementitious materials shall comply with American Standards or the relevant international codes and standards and shall consist of: Aggregates shall consist of clean, fine granular material composed of natural sand free from any impurities, and shall be well graded from course to fine consistent with good workability. Water shall be drinkable. Suspended soffits shall be securely attached to the building structure using corrosion resistant metal components. Metal lath shall be expanded sheet steel as locally supplied. The metal lath shall be supported from the suspension system at 600 mm maximum spacing between supports. All rendering coats shall consist of one part Portland cement to three parts damp, loose aggregate and ¼ part (maximum) hydrated lime. All ingredients shall be thoroughly dry-mixed. Water shall be added until mix is in a uniformly plastic condition for good plastering consistency. When necessary, plasticity shall be restored by reworking mix without further addition of water. Before each application, the base material shall be evenly dampened to control suction. The “first” coat shall be applied with sufficient pressure to form a good bond and shall be uniformly scratched. The “second” coast shall be applied a minimum of 24 hours after the “first” coast and shall be floated to a true surface and left rough. The finish coat shall be applied a minimum of 24 hours after the “second” coat. The Bidder shall submit samples of the finish coat texture and colour for approval by KNOC. Each intermediate coat shall be kept moist for a 48-hour period following application. The final coat shall be moisture cured for a 7-day period. The Bidder shall make all necessary provision for expansion joints in the cement rendering. Cracked or crazed areas shall be removed and replaced at no additional cost to the Owner. Decorative sinkage joints shall be formed in 9-80 KHABAT TPP UNITS 1&2 - VOLUME I
the finish coat where indicated on the drawings.
9.5.8
Tile work Mosaic floor tiles shall be a minimum 300 m x 300 m by 9.5 mm as a thickness of mosaic layer, glazed, with smooth, even surface, uniform in texture and free from blemishes, chips or other imperfections. Skirting sections shall be 250 mm by 125 mm coved at the base and rounded at their top edges. The floor tiles shall have a water absorption rating between 0.5% and 3.0% by weight after oven drying, boiling in distilled water for 2 hours and cooling in water up to 24 hours. The floor tiles shall be of a colour approved by KNOC. Glazed wall tiles shall be 150 mm by 150 mm by 6 mm thick, flat and free from flaws. The wall tiles shall be white in colour and shall be complete with all special edge, trim and corner sections. Glazed tiles shall be to the full height of the wall. Surfaces to receive tile works shall cleaned of all dust and loose matter. Floor surfaces shall be free from oil and other impurities which may prevent the proper bonding of the tile mortar bed. Floors to receive tiles shall be wetted down. A slurry bonding coat consisting of Portland cement and water mixed to a creamy consistency shall be brushed onto the floor surface. The mortar setting bed consisting of one part Portland cement, one-half part hydrated lime, four parts sand, and one part water (by volume) shall be placed to a thickness of 30 mm, uniformly trowelled and slightly sloped towards floor drains. The floor tiles shall receive a 3 mm setting coat of one part Portland cement to one part water (by volume) and shall be firmly and accurately set into place. Tile joints shall be straight, uniform and true in both directions. Twenty-four hours later, the tile shall be wetted, and the joints grouted, using a mixture of one part white “Medusa” grouting cement or approved equivalent to two parts sand mixed with clean water. Foot traffic shall not be permitted for minimum of 48 hours. Walls to receive tiles shall be dampened and shall receive a 6 mm scratch coat consisting of one part Portland cement, half part hydrated lime, four parts sand and one part water (by volume), trowelled rough and scored. The scratch 9-81 KHABAT TPP UNITS 1&2 - VOLUME I
coat shall be allowed to cure at least 24 hours, before applying a 9 mm thick mortar bed using same mix as scratch coat. Soak tiles in water for at least 30 minutes, and drain off excess water prior to installation. Apply a 3 mm setting coat of one part Portland cement to one part water (by volume) and tap firmly into position. Tile joints shall be straight uniform and true in both directions, accurately cut and fitted at all intersections and projections. Twenty-four hours later, the tile shall be wetted and the joints grouted using a mixture of one part white “Medusa” grouting cement or approved equivalent to two parts sand mixed with clean water. All floor and wall tile shall be thoroughly cleaned following installation. Protective coverings shall be used as directed by KNOC.
9.5.9
Suspended ceilings
9.5.9.1 General Suspended ceilings shall be installed to all circulation areas, toilets, control rooms, offices and the like, with recessed light fittings used in all such areas. The ceilings generally shall be a lay-in grid system, of a type and manufacturer approved by the KNOC. Ceiling material for all areas other than toilet and shower room areas shall have a non-flammable acoustic mineral fibre tile. Tile thickness shall be 16 mm. A moisture resistant type such as PVC panel or equivalent approved shall be used in toilet and shower room areas. The Bidder shall submit all pertinent manufacturer’s data including the method of connection to structural slabs, to KNOC for approval. The design and installation of the suspended ceiling shall be closely coordinated with mechanical and electrical requirements. Lighting fixtures ducts, diffusers and grilles shall all be installed as the work on the suspension system proceeds. The installation shall adequately support all lighting fixtures and mechanical air distribution.
9.5.9.2 Workmanship 9-82 KHABAT TPP UNITS 1&2 - VOLUME I
All suspended ceilings shall be erected in accordance with the manufacturer’s instructions and, where applicable, in accordance with the requirements of the relevant international code and standard. 9.5.9.3 Storage and protection All materials shall be transported and stored on a smooth flat base to prevent distortion and shall be kept dry. All materials shall be stored in temperature and humidity conditions similar to those in areas where they are to be finally fixed. All materials shall be protected from damage and soiling, with protective coverings retained in place for as long as possible. 9.5.9.4 Other trades Allowance shall be made for the installation of light fittings, extract fans and any other ceiling penetrations by other trades as applicable. Light fittings and ventilation ductwork shall be supported independently of the ceilings. The Bidder shall plan the erection and method of ceiling suspension in conjunction with the layouts of electrical and other services in other sections of this Contract. The ‘first fix’ work on electrical services shall be completed before the suspended ceilings are erected. Ceiling tiles, electrical and other components shall be entirely compatible in all respects. 9.5.10
Raised flooring Raised flooring to be provided in the central control room and communication room. Heavy duty raised floors to sustain an imposed UDL(uniformly distributed load) of 10 kN/sq.m with conductive tiles as appropriate, and 100 mm wooden skirting. The pedestal system shall be a heavy duty, shall be free from vibration squeaks, noise and combustion.
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The design of the system should be such that full stability is maintained when any number and configuration of the floor panels are removed. Adjustable ventilation panel shall be provided with manufacturer’s standard type where indicated on design drawings. The panel shall be able to control air quantities in accordance with the occupied areas of floor. The Bidder shall be provided for respective manufacturer’s catalogues and test reports for approval along with material samples.
9.5.11
Damp proofing The design of the floor construction shall incorporate a damp proof membrane over the complete area. The damp proof membrane shall be fully lapped and sealed at all joints and at all penetrations through the membrane. The damp proof membrane shall be continuous round all pits, channels and downstands in the substructure. The damp proof membrane shall be lapped and be fully bonded to a damp proof course in the plinth wall if this is not built from the top of the slab. The design and installation of the damp proof membrane shall fully comply with the requirements of International Building Code. The Bidder shall submit proposals for the type and detailing of all damp proofing for comment/approval by the KNOC.
9.5.12
Stairs Where the design of the buildings requires stairs to be provided, these shall comply with the requirements for means of escape for personnel, and the stairs and balustrading shall be designed to satisfy the detailed requirements of the applicable legislation. The Bidder shall submit his proposals for the design of stairs and balustrading and/or handrails for comment/approval by the KNOC.
9.5.13
Sanitary ware The detail design of the buildings shall allow for the provision of sanitary 9-84 KHABAT TPP UNITS 1&2 - VOLUME I
facilities to satisfy the appropriate standards for both male and female staff. The proposals for the detailed layout of the sanitary areas and the selection of fittings shall be submitted to the KNOC for approval/comment. In assessing the sanitary requirements, the Bidder shall assume a maximum on-site presence of approximately [15] personnel. 9.5.14
Finishes
9.5.14.1 General All finishes for floors, ceilings, walls, skirtings, window sills, worktops, casings and fittings shall be appropriate for the area in which they are to be used. The Bidder shall submit his specifications/proposals for all internal finishes and colours in all areas of each building for approval by the KNOC. The Bidder shall prepare sample boards to show his proposals for certain areas of the buildings to be selected in agreement with the KNOC. The finishes required for all buildings are set out below, these are not exhaustive and the Bidder shall provided suitable good quality finishes for areas not included.
Room name
Finishing Floor
Wall • Emulsion paint
Turbine Area Workshop area
on plinth wall
Epoxy paint
• Thermal insulated
Store area
metal cladding
Ceiling • Thermal insulated metal roofing • Steel structure
Office Conference room Cafeteria Prayer room Workshop record room Reception area
Natural granite/ mosaic tiles
Emulsion paint
Suspended acoustic mineral tile
Waiting area Kitchen Corridor
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Remarks
Finishing
Room name
Floor
Wall
Control room
Conductive tile
Communication room
(on false floor)
Electronic room Computer room UPS room MCC room
Emulsion paint
Conductive tile Emulsion paint Epoxy paint
Emulsion paint
Epoxy paint
Emulsion paint
Ceiling Suspended acoustic mineral tile Suspended acoustic mineral tile Suspended acoustic mineral tile
SWGR room Pump room Diesel Generator room HVAC room Cable room
Emulsion paint
Chiller room Tool room Tank room Storage Toilet
Unglazed
Shower room
ceramic tile
Locker room
Glazed ceramic tile
Natural granite/ mosaic tiles
Emulsion paint
Suspended PVC panel Suspended acoustic mineral tile
Acid resistant Battery room
natural granite/ Acid resistant paint
Emulsion paint
mosaic tiles Laboratory Chemical store
Acid resistant
Storage of reagent &
paint
Acid resistant paint
Suspended acoustic mineral tile
Glassware
9.5.14.2 Definitions of finishes All paint finishes shall be such as to completely cover and obscure the base construction and priming coats such that additional coats of paint will not effect a significant improvement. All paint finishes shall be consistent in colour and free from brush marks and 9-86 KHABAT TPP UNITS 1&2 - VOLUME I
Remarks
all irregularities and defects in the paint surface. Filling, stopping, knotting, grain filling and rubbing down between coats shall be carried out on surfaces as required. All finishes shall be washable with warm water containing mild detergents without affecting the finish. Drying times shall be such that dust contamination of the finished surface is kept to a minimum consistent with a good hard gloss finish. All finishes shall be of the correct type to withstand the various conditions under which the painting system shall operate. 9.5.14.3 Schedules Colour/finishes schedules shall be provided by the Bidder showing his proposals for all surface finishes, both site and factory applied, and submitted for comment/approval by the KNOC. 9.5.14.4 Painting - general Paints for priming, undercoating and finishing shall be ready mixed paints. All paints shall be supplied by an approved manufacturer who shall certify that the paint is suitable for the intended purpose. All coats of paint to give the required full application shall be manufactured by the same manufacturer. Knotting for the preparation of joinery for painting shall comply in all respects with current Standards. The colours of paints shall be approved by the KNOC on submission of the colour/finishes schedules. Any softwood timber shall be treated in accordance with the relevant international code and standard with approved preservatives. All untreated timber surfaces exposed by cutting the timber for fitting into the building shall be thoroughly treated by dipping, spraying or brushing those surfaces with the same type of preservative used for the original application, and as approved by the KNOC.
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All work shall be properly cleaned and rubbed down between each coat in a way, and using materials, recommended by the manufacturers of the paints concerned. No coat shall be commenced until the previous coat is dry, hard and satisfactory. Each coat shall be of a distinct colour from the preceding one, and all colours shall be approved by the KNOC. All paint shall be applied in accordance with the manufacturer’s recommendations and shall not contain more than the minimum quantity of thinners or dispersers necessary to permit the satisfactory application of the paint. Spray painting will not be permitted except for internal faces of walls and ceilings. All other paint shall be thoroughly brushed into, and completely cover, the surfaces. Metal doors and windows surfaces to be painted shall received the following coating systems: For metal doors and windows: 2 coats alkyd enamel, semi-gloss finish
9.5.14.5 To blockwork and plasterboard surfaces Preparation shall be according to approved practice, and application of one sealing coat matt emulsion paint with fungicidal additive and two finishing coats of approved silk vinyl emulsion paint. 9.5.14.6 Removal of fittings and ironmongery All fittings, door furniture, ironmongery, plates and labels shall be removed before painting, carefully labeled as to their exact location and replaced on completion in clean condition to the requirements of the KNOC. 9.5.14.7 Masking Where spray painting is permitted, attention shall be given to taping and masking adjacent and related surfaces for protection. 9.5.15
Flat roof waterproofing systems
9.5.15.1 Roofing materials The roof waterproofing system shall incorporate a vapour barrier, insulation to achieve a U value of 0.25W/m2C or better and a waterproof membrane by an approved Bidder.
9-88 KHABAT TPP UNITS 1&2 - VOLUME I
The roofing system shall incorporate aluminium or galvanized mild steel bent plates, to parapet upstands, galvanized to the relevant international code and standard. 9.5.15.2 Application The greatest care shall be taken to avoid damage to roof coverings at all stages of the work and any damage caused thereto shall be made good to the entire satisfaction of the KNOC at the Bidder’s expense. The roof waterproofing and insulation shall incorporate an inverted roof system complying with the relevant international code and standard. Before laying any part of the roof waterproofing system care shall be taken to ensure that the deck, vapour barrier, insulation and preceding layers are completely dry. No part of the system shall be laid in wet or otherwise unsuitable weather conditions and adequate measures shall be taken to prevent water penetration to the existing rooms during roofing operations. All roof finishes shall be guaranteed for a minimum period of ten years, in respect of both necessary repairs to the roofing system and also resultant repairs to finishes and fabric caused by any failure of the roofing system as a result of either faulty workmanship and/or faulty or inappropriate materials. A written document to this effect shall be supplied to the KNOC prior to the acceptance. All work shall be reviewed by the KNOC and samples of materials to be used shall be submitted for review, prior to roofing work commencing on Site. On completion all surplus materials are to be removed and the whole area left in a neat and tidy condition. 9.6
Materials and Workmanship
9.6.1
Codes and Standards Civil construction activities shall be carried out to the relevant American Standards or International Standards and Codes, or any local Iraqi Standards found to be more applicable in terms of materials and workmanship. The latest edition of such documents shall be used, including all current 9-89 KHABAT TPP UNITS 1&2 - VOLUME I
amendments and additions. 9.6.2
Materials Samples, technical descriptions and sources of supply of materials shall be submitted where required by the Specification to the KNOC.
9.6.3
Certification of materials Two copies, one to be submitted to the KNOC, of a certificate verifying that the materials meet the specified requirements shall be obtained by the Bidder with each delivery of materials together with the results of any tests on such materials that are required by the Specification and the relevant international codes and standards. The Bidder shall submit to the KNOC a statement detailing his test procedures and testing schedule for Site manufactured materials.
9.6.4
Storage of materials Materials shall be stored to preserve their quality and condition in a manner which complies with the manufacturer’s particular requirements.
9.6.5
Construction plant and equipment The Bidder shall provide details of plant and equipment to be used in the construction of the civil works including his proposed construction cranage strategy.
9.6.6
Concrete
9.6.6.1 General The minimum requirements for concrete work are specified in this section. Notwithstanding these requirements, the Bidder shall provide a durable concrete, fit for purpose in terms of strength and serviceability, and wholly adequate to protect concrete against the harsh soil conditions. Durable concrete shall be defined as concrete that remains free from major maintenance and repair and which provides protection against reinforcement corrosion during the intended design life of the structure. Concrete structures shall be designed for a minimum design life of 40 years. The minimum compressive (cylinder) strength of structural concrete shall be 9-90 KHABAT TPP UNITS 1&2 - VOLUME I
defined in accordance with ACI 318. The concrete mix design used for the works shall depend upon the exposure category. Two exposure categories shall be considered. Exposure category 1: All internal concrete above ground. Above ground shall be defined as upward from a level 1.0 m above grade. Exposure category 2: All concrete not in exposure category 1 (i.e. exposure category 2 shall include marine concrete, concrete in the splash zone, below ground concrete and all external exposed concrete above grade). The splash zone shall be defined as being within 100 m of the shoreline. The Bidder shall establish by Site Investigation the aggressive chemical environmental conditions for concrete exposure. Concentration levels of surface, airborne and below ground chloride and sulphate salts and any other aggressive chemical agents shall be determined. The chemical composition of below ground sulphate composition and concentrations shall be established to a degree of accuracy compatible with the limits specified in the relevant international code and standard. The Bidder shall, as a minimum requirement, comply with the concrete mix design parameters specified below. If it is deemed necessary by the Bidder to enhance the concrete mix design parameters in order to achieve the intended design life, then the Bidder shall specify additional protective measures over and above those specified. Additional protective measures include (but are not limited to) cement replacement/addition, reinforcement coatings, chemical admixtures, surface membranes and lining systems. The additional protective measures can be a combination of several provisions and the incorporation is mandatory in the contract. The cost of any such additional measures shall be deemed to be included in the Bidders offer. The Bidder shall demonstrate to the satisfaction of the KNOC that the intended design life can be fulfilled. Compliance with the concrete mix design parameters specified below shall not relieve the Bidder’s responsibility to determine his own concrete mix design, to 9-91 KHABAT TPP UNITS 1&2 - VOLUME I
fulfill the contract requirements. During the detailed design stage and following field trial analysis and subject to the agreement of the KNOC, the Bidder may propose alternative concrete mix designs to satisfy the contract requirements. The Bidder shall be responsible for ensuring that all constituent materials used for the concrete works (e.g., cement, aggregate, reinforcement, etc.) comply with recognized international material standards and methods of testing and meet the requirements of this Specification. The use of proposed constituent materials shall be agreed with the KNOC prior to their use on the Project. Trial concrete mixes shall be carried out prior to construction. Tests on fresh and hardened concrete shall be carried out to demonstrate trial mixes satisfy the requirements of this Specification. Concrete mix designs shall be agreed with the KNOC prior to construction. During construction regular tests shall be carried out on the concrete mix constituents, fresh concrete and hardened concrete. Tests shall be carried out to meet the requirements of this Specification.
The Bidders proposed
testing schedules shall be submitted and agreed with the KNOC prior to construction. Constituent materials, and test methods for materials, fresh concrete and hardened concrete shall comply with ASTM or the relevant international codes and standards. Concrete mix design parameters for reinforced concrete in exposure category 2 Cement
30%/70% combination of Portland cement and ground granulated blast furnace slag (ggbs)
Minimum ggbs/cement content 400 kg/m3 (120 kg/m3 minimum OPC but not less than 30% of the total cementitious quantity + 280 kg/m3 ggbs) 9-92 KHABAT TPP UNITS 1&2 - VOLUME I
Maximum water cement ratio
0.4
Durability enhancing admixture 10 litre/m3 of calcium nitrite corrosion inhibitor N.B.
A lesser specification based on environmental parameters and exposure conditions can be adopted for category 1 concrete mix designs. All mix designs are subject to the approval of the KNOC.
9.6.6.2 Concrete mix design parameters for plain structural concrete, i.e., thrust blocks, pipe surrounds, etc.
Cement
Sulphate resisting cement (ASTM Type V)
Minimum cement content
400 kg/m3
Maximum water cement ratio
0.4
9.6.6.3 Concrete mix design parameters for blinding concrete
Cement
Sulphate resisting cement (ASTM Type V)
Minimum cement content
200 kg/m3
Maximum water cement ratio
0.6
9.6.6.4 Cement Cements shall comply with ASTM C150.
9.6.6.5 Cement replacement Cement replacement shall comply with: A.
GGBS (blast furnace slag) to ASTM C989 or the relevant international code and standard.
B.
Pulverized fuel (fly) ash to ASTM C618
C.
Silica fume (microsilica) to ASTM C1240 (maximum 10% replacement).
9.6.6.6 Aggregates Aggregates shall comply with ASTI C33 except as modified below. 9-93 KHABAT TPP UNITS 1&2 - VOLUME I
Maximum chloride content of aggregate should be limited to 0.02% by dry weight. The potential for alkali-aggregate reactivity shall be investigated in accordance with ASTM C277/C289. 9.6.6.7 Water Water used in the concrete mix shall be potable and free from deleterious substances and shall comply with BS 3148 or similar American Standard. Furthermore, the water quality shall not exceed the following limits: A.
Iron shall not exceed 0.25 ppm
B.
Sulphate and chloride content shall not exceed 300 ppm
C.
Total dissolved solids shall not exceed 500 ppm
For corrosion protection of reinforcement in concrete, maximum soluble chloride ion concentrations shall not exceed the limits specified in the Table 4.4.1 of ACI 318. Contents of soluble chloride ion in concrete shall be tested in accordance with ASTM C 1218. 9.6.6.8 Reinforcement The Bidder shall design, supply, fabricate and install the steel reinforcement bars for the cast-in-place concrete, including all materials and measures necessary to complete the reinforcement as shown on the drawings and specified herein.
A.
Materials 1) Steel reinforcement bar shall comply with ASTM A615 and A615A, Grade 60 (413 N/mm2). Its test report done in accordance with ASTM shall be submitted for the KNOC’s approval. 2) Welded wire fabric shall conform to ASTM A185. 3) Tie wire for concrete reinforcement shall conform to ASTM A82. 4) Reinforcement placing accessories (bar supports, chairs and spacers, etc.) shall be selected by the Bidder to maintain specified concrete cover and avoid corrosion, subject to the KNOC’s approval.
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5) Epoxy coating for corrosion protection should be fusion bonded in accordance with ASTM A774A/A775. B.
Delivery and storage 1) Reinforcement bars shall be delivered to the site properly color coded or tagged according to the size and length. In case of use of tags, means shall be provided to maintain identification after bundles are broken. 2) Reinforcement bars shall be stored in the manner clear of the ground and segregated by size, length and type.
C.
Fabrication 1) Prior to fabrication of steel reinforcement, the Bidder shall submit the arrangement drawings of steel reinforcement, prepared in accordance with the ACI Manual of Standard Practice for Detailing Concrete Structures, for the approval of the KNOC. 2) All fabrication shall be done in accordance with the approved drawings. 3) Reinforcing bars shall not be bent or straightened in a manner that will injure the material. Heating of the reinforcing bars for straightening or for bending is not permitted. 4) All welding of reinforcement shall be done using welding procedures approved by the KNOC. All welding of reinforcing shall be in accordance with AWS D1.4-79 "Structural Welding Code–Reinforcing Steel". Strength welding of reinforcing bars to replace field splices shall not be used for steels in which sulfur, phosphorous, and carbon contents exceed the allowable limits of 0.06 percent each for sulfur and phosphorous, and of 0.3 percent for carbon. All bars to be field welded shall have a complete mill test report giving chemical analysis of the bars shipped with the reinforcing. 5) Tack welding on reinforcing bars is not permitted. 6) Closed ties of columns and flexural members shall have 135° bends at ends.
D.
Placing reinforcing steel 1) Prior to installation, all loose mill scale, rust, oil, paint and any other coating which cause to destroy or reduce bond between steel and concrete shall be removed.
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2) All steel reinforcement shall be installed, positively secured and supported in accordance with the approved drawings. Placing tolerances for reinforcement shall be in accordance with ACI 377. 3) On completion of installation of steel reinforcement, the Bidder shall notify the KNOC that it is ready for inspection. No reinforcement shall be covered up without the approval of the KNOC. 9.6.6.9 Admixtures Admixtures shall comply with ASTM C494. 9.6.6.10 Coatings External coatings to concrete shall comply with ACI 515.1R. 9.6.6.11 Limits for total chloride and sulphate content ASTM test method C1012 shall be used to evaluate the sulphate resistance of mixtures using combinations of cementitious materials. Maximum chloride (Cl) content by percentage weight of cement shall be limited to 0.15%. Maximum sulphate (SO3) content by percentage weight of cement shall be limited to 4%. 9.6.6.12 Formwork Formwork shall comply with ACI 347R. 9.6.6.13 Transportation Concrete shall be measured, mixed, transported and placed in accordance with ACI 304 and as follows. Concrete placement temperature shall not exceed 32°C. 9.6.6.14 Curing Water curing methods shall be adopted unless approved otherwise by the KNOC. Curing shall also comply with the requirements of ACI 308 Standard Practice for Curing Concrete, ACI 308.1 Standard Specification for Curing Concrete 9-96 KHABAT TPP UNITS 1&2 - VOLUME I
and ACI 305R, Hot Weather Concreting. Water curing shall be for a minimum of 10 days. 9.6.6.15 Concrete cover The following minimum covers are based on durability and exposure parameters.
Where a high fire rating is required for the structure then the
minimum covers required for fire resistance should be checked against the minimum requirements indicated below and the greater cover adopted. The minimum cover to reinforcement in buried concrete, or concrete exposed to seawater/river water, or spray, shall be 75 mm. For other external conditions of exposure the minimum reinforcement cover shall be 60 mm. For internal conditions of exposure minimum reinforcement cover shall be 40 mm to beams and columns and 30 mm to walls and slabs Tolerance on concrete cover shall not exceed 10 mm of the values quoted above. 9.6.6.16 Joints A.
Where shown on the drawings, or directed by the KNOC, construction joints shall be provided and preparation for them shall be in accordance with this specification. Where the Bidder proposes additional construction joints, he shall first submit drawings and obtain the approval of the KNOC.
B.
Expansion joints shall be constructed only at the locations and in accordance with the details shown on the drawings, or as directed by the Client. The faces of the joint shall be treated with two coats of asphalt bitumen and the necessary clearance between them shall be calculated.
C.
Expansion joints in slabs and beams shall be fitted with metal angles at corners and a top cover plate and, where specified or directed, shall be filled with approved compressible joint filler and sealing compound.
D.
The extruded PVC water stop shall be provided at the joint parts that contact soil. The water stop shall include necessary manufactured corner and junction pieces necessary to provide a continuous system. The concrete shall be carefully placed and vibrated around the water stops so 9-97 KHABAT TPP UNITS 1&2 - VOLUME I
as to form a complete bond between the concrete and all embedded areas of the water stop. 9.6.6.17 Grout Grout shall be “non-shrink” cementitious, and the minimum 28 day cylinder compressive strength shall be 5,000 psi grout for structural column base plates and equipment. Grout shall be mixed, placed, and cured in accordance with manufacturer’s written requirements and instructions All grout shall be placed in only one direction to prevent trapping air. Grouting shall be quick and continuous to avoid segregation, bleeding, or premature initial set. 9.6.6.18 Quality control A properly equipped independent laboratory approved by the KNOC shall conduct field tests of used concrete. The cost of testing is borne by the Bidder. The Bidder shall submit the test report related with concrete work for approval to the KNOC. The test shall be performed by independent qualified laboratory or laboratory approved by the KNOC. The execution of the concrete works, including the field quality control and performance testing should conform to all the requirements of ACI 301, Specifications for Structural Concrete for Buildings. To ensure the durability of the concrete, samples shall be tested to meet the following criteria and code requirements: A.
ASTM C 642: Standard Test Method for Density, Absorption and Voids in Hardened Concrete 1) Water absorption <4% 2) Permeable voids <10%
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B.
ASTM C 31: Standard Practice for Making and Curing Concrete Test Peccimens in the Field
C.
ASTM C 39: Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens
D.
AASHTO T277/ASTM C 1202: Standard Test Method for Electrical Indication of Concrete Ability to Resist Chloride Ion Penetration 1) Chloride permeability < 1000 coulombs.
E. 9.6.7
ASTM C 94: Standard Specification for Ready-Mixed Concrete
Setting out and monitoring All survey, setting out and leveling shall be carried out in accordance with BS 5964 using instruments and equipment which shall be regularly checked and calibrated. Information regarding site datum levels and co-ordinates may be provided by the KNOC. Setting out stations shall be accurately positioned at locations to be agreed with the KNOC and shall be adequately protected from damage during the construction of the Works. The Bidder shall carry out an accurate survey of all setting out stations relative to the site datum and shall submit details of their co-ordinates and levels to the KNOC for agreement prior to commencing any setting out of the Works. All subsequent survey and monitoring work shall be based upon the setting out stations and shall record details of the reference station used. Monitoring for movements of ground or structures shall, if required by the KNOC, be carried out by the Bidder at locations and frequencies as instructed by the KNOC. All surveys and setting out work shall be fully recorded and the details and results provided to the KNOC on completion of each section of the Works. 9-99 KHABAT TPP UNITS 1&2 - VOLUME I
9.6.8
Earthworks
9.6.8.1 General Materials, workmanship and testing procedures shall be in accordance with the appropriate ASTM or AASHTO Standards and procedures. The Bidder shall submit a document outlining his proposed materials and field testing regime which shall be agreed with the KNOC prior to the commencement of works on site. A.
The Bidder shall be responsible for the earthworks, including the excavation, dewatering, filling, backfilling, disposal of spoil material, and storage of selected material for re-use in accordance with the specification.
B.
Before earthwork is started, the location of underground utilities shall be verified. Utilities to be left in place shall be protected from damage.
C.
Excavations shall be done in ways that will prevent surface water and subsurface water from flowing into excavations and will also prevent flooding of the site and surrounding area.
9.6.8.2 Surface preparation Heavy growths of grass and other vegetation, roots, debris, stones, objects larger than 50mm in any dimensions, and other materials undesirable to the subsurface construction shall be removed by mowing, grubbing, raking, or other methods from the surface of areas to be stripped. 9.6.8.3 Stripping Topsoil shall be stripped from the surface of those areas to receive fills or embankments. Excavated topsoil shall be transported to, and stockpiled in, designated topsoil storage areas. 9.6.8.4 Clearing operations Clearing shall consist of the felling, trimming, and cutting of trees into sections and the satisfactory disposal of the trees and other vegetation designated for removal, including downed timber, snags, brush, and rubbish occurring within the areas to be cleared. The Bidder shall completely remove stumps, roots, and organic or other debris protruding through the ground surface. This material shall be excavated and removed to a depth of not less than 200 mm below the surface level of the
9-100 KHABAT TPP UNITS 1&2 - VOLUME I
original ground. 9.6.8.5 Filling depressions A.
Depressions resulting from grubbing operations shall be completely filled with acceptable backfilling material, unless further excavation or earthwork is required.
B.
Prior to filling, sub-grade surfaces of depressions shall be free of standing water. Unsatisfactory soil materials shall be removed.
C.
The Bidder shall be place fill material in horizontal layers not to exceed 150 mm in loose depth. Each layer shall be compacted at the optimum moisture content to a density equal to the original adjacent ground. Surface of filled depressions shall be graded to meet adjacent contours and to provide surface water drainage.
9.6.8.6 Excavation A.
General Before the commencement of any excavation, The Bidder shall notify the KNOC and the existing ground profile shall be measured and agreed with the KNOC. Excavations shall generally not be carried out in ground water, unless approved by the KNOC.
B.
Side slopes and working space The Bidder shall make all necessary allowance for additional excavation, as required for working space and for side slopes to ensure the stability of the excavations.
9.6.8.7 Over-Excavation If somewhere, and for any reason, excavation may be executed beyond the established lines and without the approval, The Bidder shall backfill with approved material at his own expense. 9.6.8.8 Water removal Water shall not be permitted to accumulate in excavations. Dewatering systems shall be provided by the Bidder to convey water away from excavations so that softening of foundation bottoms, footing undercutting, and soil changes detrimental to sub-grade stability and foundation will not occur. Dewatering systems and methods of disposal shall be approved by the KNOC. Dewatering shall be continued until construction subject to water pressure has 9-101 KHABAT TPP UNITS 1&2 - VOLUME I
obtained full specified strength and backfill is completed. Water removal from excavations shall be conveyed to approved collecting or runoff areas. Temporary drainage ditches and other diversions shall be provided by The Bidder and maintained outside of excavation limits. Trench excavations for utilities shall not be used for temporary drainage ditches. 9.6.8.9 Excavation for structures Excavation for structures shall conform to the dimensions and elevations indicated in the construction documents within a tolerance of plus or minus 30 mm and shall extend a sufficient distance from footings and foundations to permit placing and removal of concrete formwork, installation of services and other construction indicated, and for inspection. In excavating for footings and foundations, care shall be taken not to disturb the bottom of the excavation. Excavation to final grade shall be done just before concrete is placed. Bottoms shall be trimmed to the required lines and grades to leave a solid bed to receive concrete. If any portion of an approved foundation area is subsequently disturbed or loosened by careless operations of the Bidder, the Bidder shall, at his own expense, remove all defective material and shall replace it with concrete, or other approved compacted material, to the approved foundation level. 9.6.8.10 Excavation of ditches, gutters, and channels Excavation shall be accomplished by cutting accurately to the cross sections, grades, and elevations indicated. Excessive open-ditch or gutter excavation shall be backfilled with suitable materials to grade line at no additional cost. 9.6.8.11 Excavation for drainage structures Excavation shall be made accurately to the lines, grades, and elevations indicated on the drawing approved by the KNOC. Dimensions and elevations of footings and foundation excavations are only approximate and may be changed if necessary to ensure adequate foundation support. Trenches and foundation pits shall be of sufficient size to permit the placement and removal of forms for the full length and width of structure footings and foundations as indicated on the drawing. Rock or other hard foundation materials shall be cleaned of loose debris and cut to a firm surface, either level, stepped, or serrated, as indicated. Loose disintegrated rock and thin strata shall be 9-102 KHABAT TPP UNITS 1&2 - VOLUME I
removed. When concrete or masonry is to be placed in an excavated area, special care shall be taken not to disturb the bottom of the excavation. 9.6.8.12 Excavation for trench Trenches shall be of adequate width and depth for the specified purpose. Side slopes of the trenches shall be made as considering soil condition. Bottoms of the trenches shall be accurately graded to provide uniform bearing and support for each section of pipe on undisturbed soil at every point along its entire length except where it is necessary to excavate for bell holes and for proper sealing of pipe joints. Bell holes and depressions for joints shall be dug after the trench bottom has been graded to ensure that the pipe rests on the prepared bottom for as much of its full length as practicable. Bell holes and depressions shall be only of such length, depth, and width as required to make the joint. Stones shall be removed, as necessary, to avoid point bearing. Where rock excavation is required in trenches for pipe, the rock shall be excavated to a minimum overdepth of 150 mm below the trench depth specified. Except as specified for wet or otherwise unstable material, overdepths shall be backfilled with materials specified for backfilling the lower portion of trenches. 9.6.8.13 Temporary supports The Bidder may, at his discretion and at his own cost, use temporary supports such as timber shoring or sheet piling for the sides of excavations instead of natural side slopes. In this case, he shall submit detailed calculations and drawings for the prior approval of the KNOC, but such approval shall not relieve him from full responsibility for the adequacy of the temporary supports. Where the use of natural side slopes for excavations endangers the adjacent structures or other installations, The Bidder shall, at his own cost, provide temporary supports to the sides of his excavation as specified above. Should the KNOC consider the removal of these temporary supports to be impractical, he may direct that they be left permanently in place, at no additional cost to the KNOC. 9.6.8.14 Stockpiling of excavated material for re-use Where, in the opinion of the KNOC, excavated material is suitable to be used for fill and backfill, The Bidder shall segregate, transport and stockpile such material at the location approved by the KNOC. 9-103 KHABAT TPP UNITS 1&2 - VOLUME I
9.6.8.15 Disposal of spoil materials Unless specified or directed otherwise, all unnecessary excavated materials shall be transported and deposited outside the site at The Bidder’s own expense. It shall be disposed in the location not to disturb the environment and permit by municipal authorities. Spoil materials shall be deposited and compacted, and the side slopes shall be trimmed with gradient of not less than 1:2, so as to ensure that spoil heaps are stable and free of surface depressions so that they are drained freely and not interfere with natural drainage of the surrounding area. 9.6.8.16 Filling and backfilling A.
Materials Materials for backfill and fill shall be satisfactory soil materials, free of clay clods, rock or gravel larger than 50 mm in any dimension, debris, waste, frozen materials, and other deleterious matter. Materials shall be selected from the excavations or from an approved borrow source as directed by the KNOC.
B.
Preparations prior to backfill placement Excavations shall be backfilled as promptly as the work permits but not until completion of the following: Approval of construction below finish grade Inspection, testing, approval, and recording location of underground utilities Removal of concrete formwork Removal of shoring and bracing, backfilling of voids with satisfactory soil material, temporary sheet piling driven below bottom of structure, and cutting off and removing of utilities in a manner that prevents settlement of the structure or utilities Removal of trash and debris Completion of concrete waterproofing
9.6.8.17 Preparation of sub-grade A. Vegetation, debris, unsatisfactory soil materials, obstructions, and deleterious materials in surfaces to receive fill or in excavated areas shall
9-104 KHABAT TPP UNITS 1&2 - VOLUME I
be removed and replaced with satisfactory materials as directed by the KNOC. B. The surface shall be scarified to a depth of 150 mm before the fill is started. Sloped surfaces steeper than 1 vertical to 4 horizontal shall be plowed, stepped, benched, or broken up so that the fill material will bond with the existing material. C. When the sub-grade is part fill and part excavation or natural ground, the excavated or natural ground portion shall be scarified to a depth of 300 mm and compacted as specified for the adjacent fill. D. Material shall not be placed on surfaces that are muddy, frozen, or contain frost. E. Compaction shall be accomplished by sheep-foot rollers, pneumatic-tired rollers, steel-wheeled rollers, or other approved equipment well suited to the soil being compacted. F.
Proof rolling shall be done on an exposed sub-grade free of surface water (wet conditions resulting from rainfall) that would promote degradation of an otherwise acceptable sub-grade.
9.6.8.18 Placement and compaction A. Backfill and fill materials shall be placed in layers not more than 200 mm in loose depth. Before compaction, each layer of backfill or fill material shall be moistened or aerated as necessary to provide the optimum moisture content of the soil material and shall then be compacted to the percentage of maximum density for each area classification. Backfill or fill material shall not be placed on surfaces that are muddy, frozen, icy, or contain frost. B. Backfill and fill materials adjacent to structure shall be brought up evenly around structures and shall be carried up to the indicated elevations. C. Compaction adjacent to structures, within a horizontal distance from the face of the structure equal to the depth of backfill or fill material (measured from the bottom of footing or bottom of foundation or retaining wall) to final grade, shall be done with power-driven hand dampers. 9.6.8.19 Gravel layer The gravel shall, in principle, be laid in a single layer with no large gaps. The compaction shall be executed by a machine compact method (rammer or 9-105 KHABAT TPP UNITS 1&2 - VOLUME I
tamper), and shall be inspected by the KNOC. 9.6.9
Roads, hardstandings, car parks and paths All materials, workmanship and testing shall be in accordance with the appropriate ASTM Standards and procedures.
The Bidder shall submit a
document detailing his proposed materials and field testing regime which shall be agreed with the KNOC prior to commencement of works on site. All areas of roads or hardstanding that could be subjected to a fuel, oil or chemical spillage shall be constructed in concrete. 9.6.10
Piling
9.6.10.1 General All materials, workmanship and testing, including concrete manufactured for use in piling, shall be in accordance with the ‘Specification for Piling and Embedded Retaining Walls’ published by the Institution of Civil Engineers (ICE). If piling is required the Bidder is advised that certain types of piling plant may be unacceptable. Plant which may cause excessive vibration, noise and may lead to settlement and/or damage of adjoining buildings and structures shall not be permitted. The Bidder shall devise a static pile test programme for the approval of the KNOC. 9.6.10.2 Design The Bidder shall be responsible for all matters relating to the design, construction, setting out, installation and testing of piles in conformance with the ICE Specification stated above. The 40 years pile design life shall be assumed. All piles shall be designed with a minimum factor of safety of 2.5 applied to the ultimate pile resistance in deriving allowable pile loads. This shall apply to vertical tension and compression loads and to horizontal loads.
9-106 KHABAT TPP UNITS 1&2 - VOLUME I
Construction drawings, structural and geotechnical designs for all piles shall be submitted to the KNOC in duplicate for approval at least eight weeks before piling commences on Site. Group effects and drawn down loads shall be allowed for in pile designs and authoritative references shall be used throughout the design process. The design of piles may be based on appropriate driving formulae but minimum foundation requirements must be as calculated by soil mechanics methods using soil strength and compressibility parameters. 9.6.10.3 Pile acceptance criteria
Permissible pile settlements at proof load shall not exceed settlement criteria imposed by plant manufacturers or shall conform with the following, whichever is the most stringent: Steam
turbine
(8 mm total settlement, and 5 mm differential settlement)
Other building/plant foundations
(15 mm total settlement, and 10 mm differential settlement)
9.6.10.4 Pile testing All pile testing shall be carried out in accordance with the above referenced “Specification for Piling”. Preliminary test piles shall be required before installation of the working piles unless otherwise instructed by the KNOC.
The location of the preliminary
piles and anchorages shall be agreed with the KNOC prior to installation. On completion of the preliminary tests, piles shall be cut down a minimum of 2 m below ground level and backfilled with approved granular material. An extended proof load test shall be carried out on two preliminary compression piles and on two preliminary tension piles unless otherwise agreed and instructed by the KNOC. The Bidder shall also prove his pile designs by loading tests on selected 9-107 KHABAT TPP UNITS 1&2 - VOLUME I
working piles in respect of the settlement criteria specified above, under 1.5 times the design vertical load using the ‘Maintained Load’ test. Piles to be tested shall be nominated by the KNOC and a minimum of six proof load tests shall be allowed for. Integrity tests shall be carried out on all piles installed on Site, using an approved testing system. 9.6.11
Structural steelwork
9.6.11.1 General Materials shall be in accordance with AISC “Manual of Steel Construction Allowable Stress Design” - 9th edition. Workmanship and testing shall be in accordance with AISC “Manual of Steel Construction – Code of Standard Practice for Steel Buildings and Bridges” - 9th edition. Steel sections shall be new and of American, British, European or Japanese origin. A mixture of different national sections shall not be allowed. All structural steel sections shall be hot rolled with a minimum grade of A36 in accordance with AISC manual. Auto/manually fabricated welded sections shall only be permitted when a suitable rolled section does not exist i.e. when section required is greater than the largest section size available. All bolts in elevated steelwork connections shall be minimum grade ASTM A325. All holding down bolts shall be minimum grade ASTM A 307. All bolts shall be supplied to site sheradized and site painted after erection is complete, or alternatively hot dip galvanized bolts may be used. 9.6.11.2 Testing and inspection The Bidder shall give full access to the KNOC at all times to the place of fabrication and storage for the purpose of inspection and testing. Mill test certificates shall be provided when requested by the KNOC. When so instructed by the KNOC, the Bidder shall provide samples of the steel to be used in the Works for tests to be carried out at an independent laboratory approved by the KNOC. The cost of these independent tests shall be paid for by the Bidder.
9-108 KHABAT TPP UNITS 1&2 - VOLUME I
Should the works or any part thereof fail to pass any test or in the opinion of the KNOC fail to comply with the Specification, the Bidder shall immediately take such action as is necessary to ensure that the works comply with the Specification. All defective material and workmanship will be rejected and shall be replaced and reconstructed at the Bidder’s expense. No splice welding of members between connections shall be permitted without the prior approval of the KNOC. The Bidder shall carry out non-destructive testing of all butt welds subject to tensile stresses. Testing shall be carried out in the fabrication shop or on site as the case may be. Unless otherwise approved, non-destructive testing shall be by radiographic examination. Alternative forms of testing, if approved, shall comply with the appropriate American Standards (or the relevant international codes and standards if no suitable American Standard exists). Runway beams shall be tested in accordance with the requirements of the relevant international codes and standards and completed test certificates shall be supplied to the KNOC. 9.6.11.3 Shop drawings The Bidder shall prepare fully detailed shop drawings with supporting calculations for submission to the KNOC for comment and approval prior to commencement of any fabrication. Once approved, no changes or modifications shall be made without the KNOC’s permission. Approval by the KNOC shall not relieve the Bidder’s for the correctness of all measurements, detailing, fabrication, alignment and erection of the work.
9.6.11.4 Protection to steelwork The preparation, protection and painting systems selected for ferrous surfaces 9-109 KHABAT TPP UNITS 1&2 - VOLUME I
shall provide a life to first maintenance of 20 years. ASTM - paints and varnishes - corrosion protection of steel structures by protective paint systems and ASTM: hot dip galvanized coatings on fabricated iron and steel articles specifications and test methods shall be deemed to apply. The KNOC will select the finish colour. The Bidder shall prepare and submit, to the KNOC, four copies of a complete protection and painting schedule covering each and every item to be coated and shall fully describe the systems to be used including surface preparation, type of coating/paint, application methods, number of coats and dry film thickness of each. The Bidder’s schedule, which will also identify the paint manufacturer and include representative colour samples, will be subject to review and acceptance by the KNOC. The KNOC will be at liberty to revise the Bidder’s schedule as he deems necessary to provide the degree of protection intended, at no additional cost to the KNOC. It shall be understood that the intent of the specification is to detail a protection against corrosion and other types of damage whilst being aesthetically pleasing.
It shall be the Bidder’s responsibility to schedule and execute the
painting and coating work to this end. The following is indicative of the type of corrosion protection required for the various structural elements:
Access stairways, walkways, flooring,
Hot dip galvanized to ASTM A 123, fixed with
ladders, cladding rails and roof purlins, etc.
spun galvanized or sheradized bolts. All external fixings to be hot dip galvanized. All galvanized internal stairways are to be degreased and finished with similar paint system to the main steelwork after suitable compatible etch primer has be applied.
Main steelwork framing
Paint system to SSPC or hot dip galvanizing to ASTM A 123, to give at least 20 years to first maintenance fixed with spun galvanized or sherardized + paint bolts. Preparation - acid pickling or grit blast all surfaces to SA 2.5 SUS
9-110 KHABAT TPP UNITS 1&2 - VOLUME I
955900 or both as appropriate.
Where fire protection is required this shall be an intumescent paint system in exposed situations (subject to required fire rating being achievable), or, where concealed, a fire resistant board system will be acceptable. All corrosion protection coatings shall be applied in accordance with the manufacturers written instructions. Unless specifically approved otherwise, all coats applied to a surface shall be products of the same manufacturer. Additionally, in so far as possible and practical, paint for the work as a whole shall be products of the same manufacturer. Where any coats are damaged, all loose and damaged paint shall be removed down to the bare steel using a needle gun and/or rotary wire brush and adjacent sound paint which is to be overcoated shall be thoroughly abraded to ensure adhesion of touch-up paint, all to the satisfaction of the KNOC. Affected areas and adjacent sound paint shall be cleaned, degreased, washed down and dried and protection applied with primer overlapping abraded paint 20 mm and each succeeding coat overlapping by 20 mm. All galvanized surfaces shall be degreased prior to coating with the approved etch primer, primer and paint system. Surfaces which are to receive an intumescent fire protective coating shall be delivered to Site with travel coatings applied and shall be suitably protected until immediately prior to the fire protective coatings or casings being applied. The latter shall be applied as late as possible in the construction programme subject to other trades and operations. Primer and travel coat shall be compatible with the fire protection coating. 9.6.11.5 Erection All steelwork shall be effectively stayed as necessary during the carrying out of the Works. Finished structures shall be plumb, level and true to dimensions, within the tolerances specified in the National Structural Steelwork Specification for Building Construction.
9-111 KHABAT TPP UNITS 1&2 - VOLUME I
Prior to the erection of permanent steelwork, the Bidder shall submit for the KNOC’s approval a detailed method statement with all supporting drawings and calculations setting out his sequence for erection, laydown areas, details of carnage, etc. The KNOC’s approval shall not relieve the Bidder of his responsibilities under the Contract. 9.6.11.6 Despatch, handling and storage All bolts, nuts, washers, plates etc shall be transported to Site in properly marked and sealed containers, suitably protected to prevent damage during transportation. The Bidder shall unload and store all fabricated steel at the site. Any structural steel or accessories arriving at Site in a bent or distorted condition shall, when permitted, be properly straightened to the satisfaction of the KNOC. Any member that, in the opinion of the KNOC, has been damaged to the extent that its properties and performance in the works is suspect shall be replaced by a new member at the Bidder’s expense. Proper care shall be taken in storing and handling fabricated materials at Site to avoid damage to the member and painting. Stacking shall be carried out clear of the ground and in order of erection to reduce multiple handling. 9.6.11.7 Foundation bolts The Bidder shall provide templates to enable all stanchion bolt assemblies to be cast into the concrete foundations with the correct alignments. Holding down bolts, assemblies, templates, tubes and washers shall be delivered to the site in sufficient time to position and build them into the foundations. Boxing out for bolts shall not be permitted unless specifically requested by the plant Bidders. In such cases, the boxes shall have flared bottom providing mechanical wedging. The projection of threaded portions of bolts above the foundation level shall be adequate to properly secure the nuts. 9.6.12
Surface water drainage and buried pressure pipelines Materials, workmanship and testing shall be in accordance with the civil engineering specification for the Water Industry 5th edition published by the 9-112 KHABAT TPP UNITS 1&2 - VOLUME I
water research centre or similar American or Iraqi Specification. This document
shall
be
supplemented
by
the
construction
and
testing
recommendations. The drainage and pipeline systems shall be compatible, in all respects, with the liquids that have to be carried. 9.6.13
Building drainage All materials, workmanship and testing shall be in accordance with the manufacturer’s recommendations and the international standards or similar American or Iraqi Standards. The Bidder shall submit to the KNOC a statement detailing his test procedures and testing schedule.
9.6.14
Brickwork and blockwork All materials, workmanship and testing shall be in accordance with the relevant international code and standard. Bricks for the construction of manholes, inspection chambers, catchpits, etc., shall be Class B engineering bricks complying with the relevant international code and standard.
9.6.15
Builder’s work All materials and tests shall be in accordance with the relevant international code and standard. Workmanship shall be in accordance with the relevant international code and standard.. Construction shall be to the tolerance specified in the relevant international code and standard.
9.6.16
Access Access to and exit from the site shall be determined by the Bidder but shall be subject to agreement with the KNOC. Height restrictions both on and of the site must be observed at all times.
9.6.17
Fencing
9.6.17.1 General The Bidder shall inspect the existing boundary of the specified power plant and check its condition, and shall submit a report of his findings to the KNOC who will agree the extent, and type, of replacement/repair works necessary to refurbish the perimeter fence to an acceptable condition, or if agreed the installation of a new fencing. 9-113 KHABAT TPP UNITS 1&2 - VOLUME I
The Bidder shall also erect a new construction fence, 2.1 m high topped with three strands of barbed wire, around the perimeter of his work area. The location of this new fence shall be agreed with the KNOC. The aim of the new fence is to secure the Bidders work area for the new steam generation plant. The fence shall be provided with locked gates at agreed road crossing locations. The fencing shall be of the un-climbable, security or anti intruder type consisting of chain link mesh as specified below. It should be of robust design to deter outside intrusion. A clear opening of at least 8 m, together with an adjacent personnel gate and an electrically operated balancing lifting barrier complete with skirt shall be provided. The gates shall be operable by push button at the gate and in the adjacent gatehouse. The entrance shall be remotely monitored by CCTV at a distance from the gate house with sufficient provision of cameras to view all sides and possibly the interior of any vehicle seeking entry, before allowing reaching the gate house. The Bidder shall submit his proposals for new fencing works based upon the description of the works above and the requirements below.
His submittal
shall detail the fence materials proposed and should include, but not be limited to, the following: A.
Posts (materials, spacing, etc)
B.
Fencing fabric (inclusive of coatings type and class)
C.
Gates (vehicular an personnel access)
D.
Barrier.
The entrance gate, posts, barrier and installation shall be robust enough to halt any forced entry from a motor vehicle. If warranted the Bidder shall provide anti-intrusion barrier/ramp so that no vehicle can enter the station site without lowering the anti-intrusion barrier. 9.6.17.2 Standards The following Codes and Standards are to be used in the design and manufacture of fencing:
9-114 KHABAT TPP UNITS 1&2 - VOLUME I
ASTM A121
Specification for Zinc Coated (Galvanized) Steel Barbed Wire
ASTM A393
Specification for Zinc Coated Steel Chain Link Fence Fabric
ASTM A491
Specification for Aluminium Coated Steel Chain Link Fence Fabric
ASTM A626
Fence Fittings
ASTM A1083
Pipe, Steel, Hot Dipped, Zinc Coated (Galvanized), Welded for Fence Structures
ASTM F668
Specification for Polyvinyl chloride (PVC) Coated Steel Chain Link Fence Fabric
ASTM F900
Industrial and Commercial Swing Gates
9.6.17.3 Excavation and grading The Bidder shall clear a strip one metre wide of all growth on either side along the line of the fence and shall grade off this strip to remove local irregularities before erection of the fence commences. The Bidder shall excavate to the lines and levels required by the drawings. The base of the excavation shall be consolidated. Suitable material arising from the excavations shall be used for backfilling as needed. Surplus material shall be stored for subsequent use. 9.6.17.4 Concrete Foundation to posts, struts, bases and anti-burrowing kerbs shall be in concrete of at least 20 N/mm2. Foundations to posts shall be at least 400 mm in diameter and 1.4 m deep for line posts and 500 mm diameter and 1.6 m deep for terminal posts. Tops of foundations shall be crowned so as to shed water. Embedded steelwork in concrete shall be galvanized. 9.6.17.5 Chain link fencing, posts, gates and fittings
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Fence fabric shall be steel chain link (minimum 3.00 mm nominal diameter and maximum 50 mm mesh size) and either zinc coated to ASTM A 392 (minimum, Class 2) or aluminium coated to ASTM A491 (minimum 107 g/m2). PVC coating shall be to ASTM F668. Barbed wire shall conform to ASTM A121. Size shall be 12.5 gauges. Minimum weight of coating shall be Class 3. Top rails shall conform to ASTM F1083. Posts shall be either precast concrete, or steel conforming to ASTM F1083. Fittings shall conform to ASTM F626. Post lengths shall be at least 1m longer than the fabric height. Galvanized steel or aluminium arms shall accommodate three strands of barbed wire at 45 degrees outside of the fence line. Top strand of barbed wire shall be 300 mm above the fence fabric. Gates shall be fabricated from steel of compatible shape to the fences. Gates shall conform to ASTM F900. Frames shall be connected at joints by specially designed joints to form an inflexible panel. Galvanized steel braces shall be installed where necessary to provide inflexibility. Gates shall be provided with pre-galvanized malleable iron hinges, latches and latch catch. Latches shall be able to accommodate a padlock fastened from either side.
Hinges shall
allow 180 degree swing. Double gates shall have a centre rest, iron bolt and hold open chains. Fabric shall be as specified for fencing. Double gates shall be sized to suit the road widths or entrances for which the gates are being provided. Single personnel gates shall be the same height as the fence and shall be a 1 m wide minimum. The fencing standard may be upgraded as per contract requirements to suit the location of the site and the above standard is only the minimum requirements. 9.6.17.6 Erection Set all posts plumb and the fence line straight between corner posts and space posts uniformly. Maximum spacing between posts shall be 3 m. 9-116 KHABAT TPP UNITS 1&2 - VOLUME I
Straining posts shall be provided at all ends and corners of the fence, at changes in direction of acute variations in level and in straight lengths of fencing at intervals not exceeding 60 m. All posts shall be founded in concrete bases. The top of the base concrete shall be 50 mm above ground level. Anti-burrowing kerbs shall be bedded on in situ concrete with the top 50 mm above ground level. There shall be four rows of evenly spaced line wire. The top wire shall be doubled, making five line wires in all. The bottom wire shall not be more than 25 mm above the kerb. There shall be three rows of barbed wire at the top. The bottom 50 mm of the chain link shall be embedded into the concrete kerb. 9.6.18
Landscaping The layout of landscaped areas shall be agreed with the KNOC prior to commencement of work, including the selection of trees, plants, ground cover etc. In areas where the new works adjoin existing hard and soft landscaping, good quality landscaping shall be provided to match in with the existing environment.
9.6.19
Laydown area Laydown areas shall be established by the Bidder and shall be subject to approval by the KNOC. The Bidder shall allow for any necessary traffic management measures which are required to satisfy the local authority and highway regulations. On completion of the works, laydown areas shall be cleared of all debris, graded and laid to level and left in a tidy condition to the approval of the KNOC.
9.7
Electrical Building Services
9.7.1
Scope of works The Bidder shall be responsible for the complete design, detailed design calculations, equipment selection, installation, testing and commissioning and testing of the complete electrical building services systems subject to the approval of the KNOC. Design calculations, system diagrams and construction drawings shall be 9-117 KHABAT TPP UNITS 1&2 - VOLUME I
submitted for approval. Design information shall be submitted with description of the system and all calculations as detailed in Section 9.8.2 The Bidder shall ensure that the equipment is provided suitable for the location it is to be installed in taking into account temperature and environmental conditions expected on site. The Bidder shall include for providing all as constructed drawings, which shall be prepared as the works proceed. Completed sets of Operational and Maintenance Instructions including all tests, commissioning and any other documentation required to maintain the works shall be submitted to the KNOC for approval. 9.7.2
Lighting systems
9.7.2.1 Scope of works Lighting systems shall be provided throughout the station for all areas, outbuildings and external areas to the levels required by this Specification. The lighting system provided shall be in compliance with the Regulations, Codes and Standards and comprise normal, emergency (including operational security lighting) and external lighting systems that will include a fence security lighting system. The mounting positions of all luminaries in all areas shall be arranged to allow maintenance to be carried out on each fitting with a minimum of labor and access equipment. The design and installation of lighting and shall be based on the relevant international code & standards. All interior and exterior lighting designs shall be undertaken using computerized calculation and shall be presented using the point-by-point calculation method or flux distribution from luminaries reaching a grid of illuminance points spread across the working plane for all of the indoor and outdoor lighting. Lighting design shall take into account efficiency, symmetry, application, 9-118 KHABAT TPP UNITS 1&2 - VOLUME I
operational plant, glare that might affect the CCTV cameras, computer screen environments,
maintainability
and
long
life.
The
definitions
and
recommendations for uniformity ratio, diversity, and maintenance factor shall be comply with the requirements of the relevant international code & standards. The Bidder shall state the assumptions applied for cleaning and relamping of luminaries and ensure that these are compatible with the normal practice being applied to the local environment. The Bidder shall design using the most economical method of achieving the maintained illuminance taking into account electricity costs and lamp replacement costs etc. Lighting levels shall be graduated as required for comfort, safety and monitoring. The lighting systems will consist of the following systems. Normal lighting system 400/230 V ac serving approximately 75% of the total lighting at a given area via the lighting distribution system. The emergency lighting system 400/230V ac serving 25% of the total load at a given area and connected via a lighting distribution board. Basic source of power shall be the emergency diesel generator. The emergency lighting system shall also be capable of illuminating all exit signs, doors, stairways, corridors, other routes of exit and outside each fire exit together with other areas of specific risk. The emergency lighting system shall enable persons to make their way safely out of the area or premises without assistance. Operational (high risk task area) lighting system 230 V ac connected via distribution boards for control rooms and walkways. Basic source of power shall be from an independent dedicated UPS system. For buildings remote from the main plant and administration areas the exit signs and buildings shall be illuminated by either a local dedicated UPS or self contained battery packs. This system shall be capable of 3-hour operation Circuit design shall ensure that operation of a circuit protective device or failure of a circuit component shall result only in limited loss of illumination in a room or area. 9.7.2.2 Normal lighting 9-119 KHABAT TPP UNITS 1&2 - VOLUME I
The lighting installation, shall under normal operating conditions and throughout the stations operational life of the station be capable of providing the minimum service levels of illumination as listed below: These levels shall be based on measurements being taken after the lamps have operated for not less than 100 hours. The method of measurement is to be carried out in accordance with the International Commission of Illumination (CIE) Publication No 29. Measurements are to be generally taken at floor level. Areas typically
Description of activity
Standard maintained illuminance (lux)
Steam turbine area
Operating floor
200
Boiler house
Control areas/room
250-500
Black start/emergency
Data printers
300
Diesel generator building
Engineers/offices
300
Control and administration building
Monitoring room
300
Chiller building
Telecoms room
300
Workshop and stores
Mess room
200
Water treat plant
Metering room
200
Fire fighting pump house
Switch room
200
Cafeteria and prayer building
Toilets
150
Gatehouse
Access corridors
150
Ash blower building
HV equipment floors
150
All other relevant buildings
Marshalling room/stairwells
150
Cable floor/cable risers
50
Battery room
150
Entrance
150
Fuel oil plant room
150
Stairwells/corridors
150
Station/unit switchgear room
200
Workshop/store
300
C&I equipment
300
Electronics room
300
Switchgear room
200
Prayer room
250
Stores
200-300
9-120 KHABAT TPP UNITS 1&2 - VOLUME I
Chemical laboratory
300
Kitchens
500
Conference rooms
300-500
Locker rooms
200
Cable tunnels
50
Transformer compounds
30
If there are areas that are not included in the above, it should be used for guidance of the relevant international code & standards. The lighting shall be designed to provide visual performance, safety and amenity. Visual performance shall be free of excessive stroboscopic effects and flicker from discharge type lighting. The Bidder shall take into account the expected wall, floor and ceiling reflectance values when undertaking the design calculations. The lighting designs shall also take into account the proposed equipment locations. The Bidder shall base his design calculations on fluorescent lamps of a white color and a color-rendering index of typically 95. Lamps shall be triphosphor or multi-phosphor type. High frequency ballasts shall be provided in all fluorescent luminaries. The use of low energy/compact fluorescents will be considered wherever the location and purpose of the area is suitable. The design will incorporate energy saving systems and make possible use of local isolation, movement and presence detectors wherever such a system will provide potential energy savings. The selected luminary shall be suitable for its application. All normal lighting shall have uniformity levels (ratio of average to minimum) no less than 0.8. The type and quantity of fixtures and their luminous intensity shall relate to the space being illuminated and shall take into account the effect of the architectural space concept and color scheme. Local task lighting shall be provided as required to keep open area lighting to the minimum 9-121 KHABAT TPP UNITS 1&2 - VOLUME I
requirement. The selection of luminaries and requirements of illumination for various areas shall be in accordance with the recommendations published by the Illuminating Engineering Society with consideration of the safety and working conditions on the Project. The Bidders design shall reduce to a minimum the different types and sizes of luminaries used on the project and shall use wherever possible linear fluorescent luminaries surface mounted in plant locations. The use of one standard length fluorescent tube is preferred but this does not exclude using other lengths if required for design considerations. Luminaries shall be located as far as is reasonably practicable to allow maintenance to be carried out on each luminary with a minimum of labor and access equipment 9.7.2.3 Emergency lighting All emergency lighting schemes shall be arranged to provide the required illumination on interruption or failure of normal lighting supply, operation of a circuit breaker or fuse or manual acts such as accidental opening of a switch controlling normal lighting facilities. The Bidder shall design, supply, install, wire and connect up a complete emergency lighting installation with a minimum of 3-hour operation, which shall be carried out in accordance with IEC or the relevant international code & standards. Emergency lighting including operational (high risk task area) lighting system shall be supplied to all areas. The emergency lighting system shall consist of the following types of fittings: A.
non-maintained 230 V ac
B.
maintained 230 V ac.
Emergency lighting (operational (high risk task area) lighting system) fed by the dedicated UPS system -
Fluorescent luminaries,
15 lux at floor level
Non-maintained
operational areas 9-122 KHABAT TPP UNITS 1&2 - VOLUME I
-
Fluorescent luminaries or high
15 lux at floor level
Non-maintained
100 lux at floor level
Maintained
bay metal halide discharge luminaries with auxiliary lamp for instant illumination inside the electrical operational rooms. -
Fluorescent luminaries inside switchboard/electronics rooms to serve as standby lighting
-
Illuminated exit signs of all final
Maintained, self-
exit doors (non UPS supply)
contained bulkheads
-
High bay metal halide discharge 15 lux at operating floor level)
Non-maintained
luminaries with auxiliary lamp for instant illumination -
Floodlight type units mounted
15 lux at floor level
Non-maintained
on the turbine/generator house side walls area. Emergency lighting on paths of egress at floor level shall have a maximum-tominimum illumination uniformity ratio of 40 to 1, which shall not be exceeded. The emergency lighting for stairs and escalators shall emphasize illumination on the top and bottom landings and at all intermediate landings The emergency lighting shall be arranged to come into operation automatically upon failure of the normal lighting sub-circuit failure. 9.7.2.4 External lighting The Bidder shall design supply, install wire and connect up a complete external lighting system for all areas of the development. The detailed positioning of all lighting points to achieve the illumination levels shall be subject to the approval of the KNOC and must be in uniform and 9-123 KHABAT TPP UNITS 1&2 - VOLUME I
symmetrical arrangement. All lighting shall be designed to meet the requirements of lighting guide LG06: 1992. For the outdoor environment issued by the Chartered Institution of Building Services Engineers. Illumination levels shall also be in accordance with the lux levels indicated below. Where these two contradict the more onerous shall take precedence. Where a range of average illuminances are recommended in the guide for a particular application, the Bidder shall design his lighting scheme to provide an illuminance not less than midway between the recommended upper and lower valves. Transformer area
30 lux
Fluorescent
Machinery areas
200 lux
Metal Halide
Platforms/ladders (active)
50 lux
HP Sodium
Walkways
50 lux
HP SODIUM
Road, platform/ladders (inactive),
30 lux
HP Sodium
Operating plant areas:
The security fence shall be continuously illuminated during hours of darkness by linear low-pressure sodium lighting to provide an even vertical illuminance of 25 lux on the face of the fence. These low mounted lights will allow the security patrol personnel to view the surveyed area. This shall be undertaken utilizing luminaries installed on 3 m high hot dipped galvanized columns When lighting columns are required, these shall be complete with luminaries’ mounted at suitable heights in accordance with design calculations and at suitable mounting locations. All external doors of buildings shall have external luminaries installed adjacent to the doors to provide illumination immediately outside entrances. This is in addition to any other external or roadway lighting. 9-124 KHABAT TPP UNITS 1&2 - VOLUME I
9.7.2.5 Related standards A.
IEC 60364
B. IEC 60064
Electrical Installations of Buildings Specification for tungsten filament lamps for general service (batch testing).
C.
IEC 60598
Luminaires Pt 1 General requirements and tests Pt 2 Detail requirements
D.
IEC 60081
Tubular fluorescent lamps for general lighting service.
E.
IEC 60921
Specification for ballast for tubular fluorescent lamps.
F.
IEC 60188
High-pressure mercury vapour lamps
G. IEC 62035
(excluding Fluorescent Lamps)
H.
IEC 60662
High-pressure sodium lamps
I.
IEC 60947
Low-voltage switchgear and control gear
J.
Codes for Interior and exterior lighting (Chartered Institute of Building Services Engineers.)
9.7.2.6 Materials Luminaries The luminaries used shall be recessed or surface mounted as appropriate. Diffusers shall be used taking into account the glare requirements of the various areas. Discharge lighting shall be provided
for high/low bay areas,
and for floodlighting as appropriate. The IP rating of the luminaries shall be in accordance with the environment in which they are installed. 9.7.2.7 Switches Switch types shall include single or multi-pole, one way, two-way and 9-125 KHABAT TPP UNITS 1&2 - VOLUME I
intermediate with or without pilot lamps, as may be required for each application. All areas shall be individually switched with two ways and intermediate switching provided where necessary if there is more than one method of access and for walkways and stairways. Luminaries installed on different floor levels or at different task locations to be controlled by their own switches. Light switches for indoor use shall be the quiet rocker-dolly type of thermoplastic material flash or surface mounting, with the degree of protection suitable to the environmental conditions of the specific area of the substation. Where required by the design push buttons shall be provided for the control of large open area lighting installations. Push buttons shall be positive action, spring loaded having a ‘stay put' contact action with push to close and push to open action. Push buttons shall be 5 A rated at and shall have chromium plated steel cover plates. All cover plates for lighting control switches shall be chromium-plated steel. 9.7.2.8 Lighting contactors Contactors controlling outgoing circuits shall be located within the local distribution board and shall be rated for ‘continuous load' condition. Contactors located within the boards do not require a separate enclosure but the construction of the contactor shall be such that it is not possible to come into contact with any live parts. The operating coil shall be suitable for operation at 230 volts 50 Hz single phase. 9.7.2.9 Workmanship The mounting height of luminaries shall not be lower than 2.4 m unless restricted by the available mounting height or if otherwise approved. The Bidder shall include all the brackets, supports and fixings, which may be required. Where provided, supports and brackets shall be hot dip galvanized and given an additional coat of epoxy paint. All fluorescent fittings are required to strike successfully at 85% nominal volts and not to extinguish at 70% nominal volts.
9-126 KHABAT TPP UNITS 1&2 - VOLUME I
All discharge lamps shall have an operating power factor of not less than 0.85. 9.7.2.10 Lamps and tubes Lamps and tubes installed in the luminaries shall be of approved manufacture and of the correct type, voltage and rating specified in accordance with the related standard. Fluorescent lamps shall be cool daylight with a minimum life of 7500 hours. High-pressure sodium discharge lamps shall be color corrected deluxe white with a minimum lamp life of 24 000 hours operation with the required ballasts. 9.7.2.11 Lighting and control switches Local switches shall generally control the lighting. Separate switches shall also be provided for local lighting for panels etc and comply with the related Standard. In the central control room the fluorescent lighting shall be provided with "dimming" control to give a graded reduction in lighting levels In large areas, such as the turbine house, luminaries for access and inspection lighting shall be switched by contactors controlled by a switch adjacent to the plant covered by a specific load centre. The design of general and local lighting control shall comply with the following requirements: A.
Not more than ten lighting points to be connected to and final sub-circuit.
B.
Two way switches with intermediate where necessary, to be provided for lighting in areas with more than one access, walkways and stairways.
C.
Luminaires installed on different floor levels or at different task locations to be controlled by local switches.
Lighting switches shall be selected in accordance with the ON/OFF control requirements of the lighting load and rated for 230 V ac single-phase operations with minimum capacity of 2500 W. All switches shall be mounted at 1.5 meters above finished floor or platform levels. The switches shall be positioned such that they can be easily located and accessed for use.
9-127 KHABAT TPP UNITS 1&2 - VOLUME I
The external lighting installation shall be contactor controlled using photoelectric cells. 9.7.3
Small power installation
9.7.3.1 Scope of works The station and any ancillary areas shall be equipped with socket outlets, connection units and isolators to suit the purpose of each building or area. These outlets will be suitable for providing power supplies to all portable equipment, hand tools, portable lamps and fixed equipment required for operating and maintaining the systems For office areas, equipment and control rooms, maintenance and testing areas or similar, the socket outlet layout shall be designed so as to effectively cover work areas with a 3 meter flexible cable. Socket layout design for all other areas shall give effective cover with a 15 meter portable extension. 110 V socket outlets shall be provided in plant areas to supply power for hand tools etc used for maintenance. The Bidder shall design supply and install a complete small power installation which shall comprise of 230 V/13 A socket outlets, 400 V/200 A oil filtration sockets, 400 V/63 A welding sockets, industrial outlets for plant areas 230 V/15 A and 13 A fused connection units and isolators for various items of fixed appliances. The 230 V sockets shall be wired as ring main circuits whilst 400 V sockets shall be wired as ring/radial circuits the 230 V switched 13 A socket outlets shall be flush mounted in offices and office type areas. 9.7.3.2 110 V power sockets A 110 V switched socket outlet system shall be provided in plant areas to supply power for hand tools etc used for maintenance and shall give effective cover with a 15 meter portable extension. The plugs and outlets when in use shall be IP44 splash proof complying with IEC 60309 and the relevant international code & standards. 9.7.3.3 230 V power sockets A 13 A 230 V socket outlet system (2 pole plus earth) will be provided for offices areas, main plant areas, store areas, equipment and control rooms. This installation will be of the surface/concealed type and will be designed to 9-128 KHABAT TPP UNITS 1&2 - VOLUME I
provide effective cover to all work areas with a 3 meter flexible cable. The Contract shall provide sufficient sockets for general purposes in all operational areas. Single-phase socket outlets - 15 A. Single phase 230 V, 15 A socket outlets, connected to the normal power supply shall be of the two gang, 3-pin type in accordance with the relevant international code & standards. Socket outlet installations for plant room areas shall be surface mounted and shall be located to provide effective cover with a 15 meter portable extension lead. Socket outlets rated at 15 A, 230 V single phase shall be provided for all fixed items of equipment such as small local water heaters and extractor fans etc. A RCBO rated to trip at 30 mA at the local distribution board shall protect each small power ring main or radial circuit. 9.7.3.4 230 V power accessories Cooker control units shall be provided for kitchen cooking stoves consisting of a 45 amp, double pole main switch with pilot lamp and a connector unit complete with terminal blocks, cable clamps and cover plate. Water heater switches shall be rated 15 amp, 20 amp or 45 amp depending on load requirements with red pilot lamp and switch plate engraved ‘Water Heater'. Hand dryer switches shall be rated 15 amp with red pilot lamp and switch plate engraved ‘Hand Dryer'. 9.7.3.5 400 V socket outlets Power socket outlets shall be rated at either 16 A, 32 A, 63 A or 200 A and shall have 4 pole connections and two earth connections. The Bidder shall provide socket outlets in all oil filled transformer compounds for the connection of a mobile oil purification plant. The socket outlets shall be located so that the mobile oil purification plant can be positioned in front of each transformer bay using a maximum cable length of 20 meters. The Bidder shall supply and install welding socket outlets complete with plugs at strategic points located on a nominal 50 meter grid so that all parts of the 9-129 KHABAT TPP UNITS 1&2 - VOLUME I
Plant can be reached using a maximum cable length of 35 meters. The socket outlets shall be 400 V, 63 A, three phase, neutral and earth to the relevant international
code
& standards.
They
shall
incorporate
an
on-load
disconnector, MCB rated to suit the switch and a residual current circuit device (RCBO) rated at 30 mA.
9.7.3.6 Related Standards
A. IEC 60364-5-54
Earthing
arrangements
and
protective
conductors for indoor installations up to 1000 V ac and 1500 V dc B.
IEC 60309
Plug and socket outlets
C. IEC 60309
Plugs,
socket-outlets
and
couplers
for
industrial purposes
9.7.3.7 Material Socket outlets shall be metalclad to IP67, watertight and incorporate a springreturn flap cover. The plug and socket shall be interlocked such that the unit cannot be switched on until the matching plug is fully inserted, nor can the plug be withdrawn with the switch closed. 9.7.3.8 Workmanship The mounting height of general-purpose socket outlets and power socket outlets shall be as follows: General-purpose socket outlets mounted in walls of rooms such as offices and control room areas shall be 300 mm above finished floor. In all other maintenance type areas, equipment or station areas the mounting height shall be 600 mm above finished floor. Power socket outlets shall be mounted 1.2 meters above finished floor. The KNOC at site shall approve the position of all socket outlets before installation work is commenced 9-130 KHABAT TPP UNITS 1&2 - VOLUME I
9.7.4
Distribution system
9.7.4.1 Scope of works Sub distribution boards shall be provided for the lighting and small power supplies throughout the station. A unique code number shall designate to them and all drawings and diagrams. The boards shall be 400/230 V ac 3 phase and neutral, generally grouped together where suitable, within a free standing floor mounted totally enclosed cellular cubicle type switchboard or as individual boards where required. Each board shall be equipped with main incomer and sub-main circuit breakers. The design shall ensure that all equipment is provided that will take the expected symmetrical fault rating and shall be capable of breaking rated load current. Lighting and small power final sub-circuits shall be supplied from ways protected by miniature circuit breakers. A minimum of 20% of each type and rating of MCB/RCCD ways shall be provided as spares.
9.7.4.2 Related Standards A.
IEC 60947
Distribution boards and all components
9.7.4.3 Material Sub-main circuit breakers shall be of the molded case plug-in and bolted type selected in accordance with the load served and to withstand the actual fault levels at the bus bars. Miniature circuit breakers of the residual current earth leakage type shall be used for socket outlet feeds and some small power supplies. Sub-distribution boards combining lighting circuits and socket outlet circuits shall be electrically separated by the provision of separate bus bars and the socket outlet section shall be protected by RCBO.
9-131 KHABAT TPP UNITS 1&2 - VOLUME I
The emergency lighting shall be operated (i.e., switched on due to ac failure) when the voltage of any one phase drops to 80% of normal supply voltage. The relay shall be able to detect when the 400 V ac supply voltage has fallen to 80% for half a cycle and to energize the emergency lighting within 0.5 seconds. Upon restoration of normal ac supplies a suitable delay shall occur before the emergency lighting are switched off. A timer linked to the low voltage relay shall provide this function but shall not be included where fluorescent tubes are used for the ac lighting. The low voltage relay shall be equipped with a manual override to provide a lamp test facility for the emergency lighting or switch it on manually should the automatic system fail. The 400/110 V ac power socket boards shall be fed from 4 kVA transformers for each group of 110 V ac socket outlets. 9.7.4.4 Workmanship Distribution boards shall have an enclosure of zinc coated or galvanized steel of minimum thickness of 1.8 mm, having a hinged door with padlocking. Enclosures shall have a degree of protection to IP 20 for office type rooms (indoor locations) IP 44 for indoor locations in plant areas and IP 65 for outdoors and damp situations. Access doors shall open 120° without obstruction to give access for operation of switches for MCB and RCDs. The local distribution boards shall be generally mounted at 1450 mm above ground level with a clear working space of 1000mmfor operation testing and maintenance. Gland plates shall be fitted to both top and bottom for cable entries to incoming and outgoing circuits and allow for spare capacity 9.7.5
Cables and wiring
9.7.5.1 Scope of works The types of cables that can be used are in Section 7.15 Cabling. Segregation of ac and dc cables should be in accordance with the related Codes and Standards. The minimum cross section of cables to supply luminaries is 2.5 mm2 and for 9-132 KHABAT TPP UNITS 1&2 - VOLUME I
power outlets circuits shall be 4.0 mm2 cables. 9.7.5.2 Workmanship Lighting suspension trunking shall be manufactured from heavy gauge sheet steel with a galvanized finish complying with the related Standard. Trunking shall be complete with all manufactured standard couplings, bends, tees, cable retainers, stirrup suspension, hangers and fixing brackets and all other accessories as required. Self-tapping screws shall not be used in the trunking assembly and the inner surface of the trunking shall have a smooth finish. All conduits terminating at the trunking shall be bonded together and to the trunking. The trunking shall not form part of the earth continuity conductor and separate earth conductor shall be provided in the trunking. Copper earth bonding links shall be fitted across all joints. 9.7.6
Lightning protection system
9.7.6.1 Scope of works The Bidder shall provide and install a lightning protection system to provide the necessary protection to each building. Each building shall have its own air terminal network, down coming tapes and earth points. The complete installation shall comply with the requirements of the relevant international code & standards. The Bidder shall connect together with a perimeter conductor all earth rods of each individual lightning system. From the nearest point of the perimeter conductor the Bidder shall provide a link to the power plant earthing system as detailed in Section 7.14.
9.7.6.2 Workmanship Joints between lightning protection conductors shall be accessible without disturbing the roof structure, no joints located below roof finish will be accepted. At ground level the down conductor shall terminate at a brass test clamp 9-133 KHABAT TPP UNITS 1&2 - VOLUME I
mounted at 1500 mm above finished floor level. The earth electrode shall comprise as a minimum 4 No 1200 mm, 15 mm diameter, hard drawn solid copper ground rods, screw coupled. See Section 7.14 for ground testing requirements. Final connection to the electrode rod shall be by a pressure type clamp connection. The complete installation shall be tested in accordance with the relevant Standards. The Bidder shall provide the KNOC with copies of the test certificate produced for the lightning protection system. Surge arrestors to be fitted for protection against transient surges that occur during lightning strikes. 9.7.6.3 Bonding The Bidder shall include for bonding all items of exposed extraneous metalwork, i.e., masts, AHUs, etc. and louvers, to the lightning protection system. A separate electronic earthing system shall be installed as per the latest Codes and Standards for all electronic and communication systems. This system shall be separate from the plant protective bonding system. The Building Services systems shall all be bonded to the nearest earthing point distribution bar normally located within the electrical equipment rooms. The earthing arrangement and protective conductor system shall be in accordance with IEC or the relevant international code & standards. 9.8
Mechanical Building Services
9.8.1
HVAC systems
9.8.1.1 Design/systems requirements The HVAC systems shall be designed, installed and commissioned in accordance with the latest applicable codes of the following: A.
ASHRAE.
American Society of Heating, Refrigerating and Air Conditioning Engineers. 9-134 KHABAT TPP UNITS 1&2 - VOLUME I
B. SMACNA.
Sheet Metal and Air Conditioning Bidders National Association.
C.
NFPA.
National Fire Protection Association.
D.
ARI.
American Refrigeration Institute.
E.
ANSI.
American National Standards Institute.
F.
AABC.
Associated Air Balance Council.
All systems shall be designed and installed to provide acceptable environmental conditions for each area as specified below. The conditions of temperature, humidity, air movement and air filtration shall be controlled as required in the respective areas in summer and winter. HVAC systems serving critical areas such as Control Rooms shall be provided with duty/standby air handling and mechanical cooling plant to ensure continuity of operation. HVAC systems shall be arranged to shut down in the event of a fire alarm, seal supply and extract ducts as required for the application of clean agent fire suppression systems, and start up smoke control pressurization systems. Provision shall be made in all plant areas for the venting and clearance of smoke and fumes in the event of fire, by means of roof vents or extract fans. All systems and components shall be suitable for the design life of the plant, and be designed for minimum life cycle cost and complexity, consistent with functionality, ease of maintenance and reliability 9.8.1.2 Ambient design conditions For all general cases the HVAC systems the ambient design conditions shall be as follows. Outside design conditions for Air Conditioning System - Summer
48°C db
30°C wb
- Winter
4.4°C db
1.7°C wb 9-135 KHABAT TPP UNITS 1&2 - VOLUME I
The HVAC conditions described here cover the majority of sites in Iraq but extreme temperature ranges, as stated in other parts of the Specification, are possible in small number of cases. Bidder shall, based on the general requirements described below, implement small adjustments to suit the local extreme condition which could be high temperature, low temperature or high altitude. 9.8.1.3 Internal design conditions The HVAC systems shall be designed to obtain the internal conditions and system redundancy as indicated in the following table. Area (s) Power
Room
Internal Condition
Turbine hall
50 ºC db max.
System Requirement -Air conditioning systems (duty/standby)
Block
-Min. 6 AC/h ventilation.
Control rooms
Summer:
-Central air conditioning systems with
Electronic rooms
26ºC db ± 1.5ºC
50% air handling units (duty/standby)
50% R.H ± 5%
with humidifier.
Winter:
-Individual air cooling system with (N+1)
22ºC ± 1.5ºC
x (100/N)% split air conditioner with
40% R.H minimum
humidifier.
Offices
Summer:
-Central air conditioning systems with
Laboratories
26ºC db ± 1.5ºC
50% air handling units (duty/standby)
Relay room
50% R.H ± 5%
with humidifier.
Switchgear room
Winter:
-Individual air cooling system with (N+1)
Rectifier/inverter
22ºC ± 1.5ºC
x (100/N)% split air conditioner.
MCC room
40% R.H minimum
Electrical
panel
C
room Excitation
42ºC. db max.
Air conditioning systems (duty/standby).
20ºC. db min
Battery rooms
42ºC. db max.
100% exhaust fan(duty/standby).
20ºC. db min
Max 1% hydrogen concentration.
9-136 KHABAT TPP UNITS 1&2 - VOLUME I
Rooms under negative pressure. Auxiliary
Standby
diesel
System
generator
55ºC db max.
Supply/extract ventilation for “normal”
No winter heating.
operation (DG off) plus boost ventilation
room
(DG running) to DG. Manufacturer’s requirements.
Workshop area
42ºC. db max.
- Air conditioning systems
Storage area
No winter heating.
- Min. 6 AC/h ventilation.
Laboratories
Summer:
- Individual air cooling system with
26ºC db ± 1.5ºC
100% split air conditioner
Winter:
- Min. 6 AC/h ventilation.
22ºC ± 1.5ºC
Chiller
building
42ºC max.
Air conditioning systems with
No winter heating.
ventilation.
42ºC max.
Air conditioning systems with
building (hall)
15C min.
ventilation.
Fire pump house
42ºC max.
-Air conditioning systems with
Fuel
No winter heating.
ventilation.
(hall)
Water
treatment
oil
pump
house
-Smoke extract system for DG driven fire pump, with fresh air inlet.
Common
Office
Summer:
-Individual air cooling system with 100%
Area
Lecture room
26ºC db ± 1.5ºC
split air conditioner
Prayer room
Winter: 22ºC ± 1.5ºC
Corridors.
28C db max.
Pressurization systems for smoke
Stairs.
20C db min.
control may be required in these areas.
9-137 KHABAT TPP UNITS 1&2 - VOLUME I
Toilets
Mess rooms.
28C db max
Extract ventilation (10 AC/h min.)
10C db min.
Rooms under negative pressure.
28C db max.
Extract ventilation (6 AC/h min.)
15C db min.
Rooms under negative pressure.
9.8.1.4 Sound levels The sound levels in plant and occupied areas shall not exceed the following, with HVAC systems only in operation. Switchgear Rooms, Relay Rooms
NC55
Control Rooms, Offices, Prayer Rooms
NC40
Workshops, Mess Rooms, Toilets, Corridors
NC45
Sound attenuators shall be provided in duct systems, as required to achieve the above sound levels.
9.8.1.5 Fresh air requirements Fresh air shall be supplied for the following purposes. A.
Fresh air for occupied areas, minimum 15 litres/second/per person
B.
Free cooling during periods of low ambient temperatures
C.
Make-up air for exhaust ventilation systems
D.
Building pressurization to exclude dust. Minimum fresh air supply shall not be less than 5% of supply air volume.
Fresh air supplies shall be obtained from areas not subject to contamination from fumes. Air intakes shall be located at maximum available height, to reduce dust load. 9.8.1.6 Mechanical cooling Mechanical cooling requirements shall be met by a central chilled water plant serving all cooling loads on the project. [Direct-expansion refrigeration plant may be used for projects where cooling load is less than 500 kW, or for small 9-138 KHABAT TPP UNITS 1&2 - VOLUME I
cooling loads remote from the central plant] In all cases, standby plant shall be provided for critical areas, as detailed below. Water-cooled chillers shall be used on sites where adequate water supplies are available to support cooling tower operation, otherwise chillers shall be aircooled. Cooling towers shall be matched to chillers, and sized for 32°C ambient wet bulb temperature. Condenser water pumps shall be matched to cooling towers. Air-cooled condensers shall be rated for 50°C ambient dry bulb temperature. Three chillers, each rated at 50% of design maximum cooling load, shall be provided, for two duty, one standby operation. Chillers shall be open centrifugal or scroll compressor (dual circuit) type, with capacity control to provide stable operation down to 10% of design cooling load. All chillers shall comply with the requirements of ARI550/590 -Water Chilling Packages using the Vapour Compression Cycle. Refrigerant shall be R134a or equivalent. HFCF refrigerants shall not be used. Refrigerant piping and components shall comply with ASME B31.5 Refrigerant Piping - and UL 207 - Refrigerant containing Components and Accessories. The units and complete installation shall comply with ASHRAE 15 - Safety Code for Mechanical Refrigeration - and ASHRAE Guideline 3 for Refrigerant Leaks, Recovery, Handling and Storage Requirements. Primary and secondary chilled water circuits shall be provided for all central systems, with primary pumps for each water chiller and duty/standby pumps for each secondary circuit. Secondary circuits shall be provided to match the chilled water temperatures required for the various systems. Air conditioning systems cooling coils shall be designed to give high return water temperatures under all load conditions, to reduce pump/pipe sizes and pumping costs. Service trenches shall be provided for distribution pipework to the various buildings around the site. Central chilled water systems shall be complete with all necessary ancillary 9-139 KHABAT TPP UNITS 1&2 - VOLUME I
plant and systems as follows. A.
Pressurization/expansion vessels and pumps
B.
Water treatment plant
C.
Refrigerant handling and storage
D.
Refrigerant leak detection
E.
Condenser ball cleaning system.
The above plant, along with water-cooled chillers, primary/secondary pumps, control equipment etc. shall be accommodated in the Chiller Hall. Direct expansion refrigeration plant shall be air cooled, with condensers rated for 48C ambient dry bulb. All systems shall be ARI rated, and use HFC refrigerants. HFCF refrigerants shall only be used for small systems, 9.8.1.7 Emergency chillers For sites using central chilled water systems, critical air-conditioning systems requiring 100% standby plant shall be provided with emergency chillers for use in the event of failure of the central system. Emergency chillers shall be air-cooled units, with screw or scroll compressors (dual circuit) and capacity control down to 20%. Units shall be capable of matching system requirements at 50°C ambient temperature. Standards shall be as for the central plant chillers. HCFC refrigerants shall not be used. The emergency chillers shall be complete with pressurization unit, duplicate circulating pumps and interconnecting pipework to the central chilled water systems. Interconnecting pipework shall be complete with automatic changeover valves. [The emergency chillers and associated air handling plant shall be powered from maintained electricity supplies available during blackout conditions.] 9.8.1.8 HVAC systems - general requirements Air-conditioning systems shall be provided to serve areas classified as low 9-140 KHABAT TPP UNITS 1&2 - VOLUME I
temperature (26°C) and medium temperature (35°C and above). Except where areas have separate exhaust ventilation (e.g., battery rooms), low and medium temperature areas shall not be served from a common system. All systems shall be designed and installed to be robust and reliable in service, easily maintained and of minimum life cycle cost. Low temperature systems shall employ recirculation air ductwork where possible to reduce fresh air cooling loads. Fresh air supply shall be in accordance with the requirements of Section 9.8.5. Medium temperature systems shall employ return air ductwork for use in summer (mechanical cooling) and up to 100% fresh air for use in winter (free cooling). Fresh air supply in summer to be to be 5% minimum, as indicated in Section 9.8.5. Dedicated exhaust air systems shall be provided for battery rooms, toilets, kitchens and chemical areas. Systems for battery rooms shall include separated supply air system and duty/standby fans, with automatic changeover for duty fan failure and duty sharing. Exhaust duct works and exhaust fans for battery room shall be made of acid resistant synthetic material. Exhaust fans shall be explosion proof. Provision shall be made in all recirculation systems for venting of smoke/fumes after a fire incident. Pressurization systems shall be provided for stairwells and corridors (escape routes) as required by the Fire Codes.
Fans shall be powered from
maintained electricity supplies, and operated through the fire detection system. Systems shall be complete in all respects, including all necessary components, pipe and duct insulation, drains, instrumentation, motors, cabling etc. The following clauses indicate specific requirements for systems and for various components. 9.8.1.9 Ductwork Ductwork shall be fabricated, installed and tested in accordance with the latest 9-141 KHABAT TPP UNITS 1&2 - VOLUME I
SMACNA Standards. General supply and extract system ductwork shall be of galvanized
sheet
steel
construction.
Irrespective
of
pressure/velocity
classification, ductwork at low level in plant rooms and in areas subject to mechanical damage shall be constructed (as a minimum) to medium pressure standard. All duct systems shall be complete with dampers to facilitate balancing. Splitter dampers will not be accepted. Access doors shall be provided as required for inspection/maintenance of dampers, fire dampers, instruments etc. Final connections to ceiling-mounted supply and extract terminals may be carried out in insulated flexible ductwork. Extract system ductwork from battery rooms and chemical areas shall be of PVC construction. High pressure ductwork shall be pressure/leak tested. Low and medium pressure ductwork need not be tested, except where located outdoors. The following ductwork shall be insulated in accordance with the requirements of Specification in mechanical Section A.
Fresh air ductwork
B.
Low Temperature supply and extract ductwork.
C.
Medium temperature supply ductwork.
D.
Ductwork in Electrical rooms, where subject to condensation.
9.8.1.10 Air filtration Fresh air intakes on large central systems shall have with inertial type sand filters with bleed fans and access sections behind.
Small systems employing
fixed volumes of fresh air shall be provided with sand louvers. Primary and fresh air filters on all systems shall be permanent metal panel washable type, [dust spot efficiency 20%]. A complete set of spare cells shall be provided for cleaning, along with coating fluids. Washing facilities shall be provided, with Service water being used for cleaning. Secondary air filters on medium temperature systems serving plant areas shall 9-142 KHABAT TPP UNITS 1&2 - VOLUME I
be replaceable bag filters, dust spot efficiency 50%. Secondary air filters on low temperature systems serving offices/control rooms/electronic areas shall be replaceable bag filters, dust spot efficiency 90%. All bag filters shall be supported in proprietary mounting frames for front or side withdrawal. The Bidder shall supply a sufficient number of replacement cells to last during the test periods and during the defects liability period, with one complete set being provided at that the end of the Defects Liability period. 9.8.1.11 Fresh air conditioning Central air-conditioning systems having humidity control may be provided with air handling units for fresh air supply. These units shall be provided with cooling
coils
and
steam
humidifiers
to
handle
the
full
dehumidification/humidification load for the central system, with dew point control. Fresh air cooling coils shall have 10% margin on heat transfer surface to cater for periods of abnormally high humidity. Face air velocity shall not exceed 2.0 m/sec. Humidification shall be by electric powered steam generators with proportional control and steam lance injection. 9.8.1.12 Fire/smoke dampers Fire dampers to UL Standards and NFPA-90A shall be provided on ductwork systems passing through firewalls and floors, and as required for compartmentation of gas fire suppression systems. Dampers shall be operated by fusible link and (re-settable) damper motor, suitable for actuation through the fire detection system and fire damper control panel. Smoke dampers for clean agent fire suppression systems shall be motor operated/solenoid actuated for closing and opening purposes. Damper status shall be indicated on the control panel mounted adjacent to the Fire Control panel. 9.8.1.13 HVAC controls All HVAC units and systems shall be provided with local control panels for local manual/automatic control. Data gathering panels (DGP) shall be provided as required (typically one per plant room/area) to interface controls and status indicators/alarms to a BMS for remote control. All system status, 9-143 KHABAT TPP UNITS 1&2 - VOLUME I
alarms, set point indication etc shall be available at the remote station as well as at the local control point. The BMS control station shall be located in the Main Control Room. 9.8.1.14 Power supplies The Bidder shall include for all power and control cabling, MCC and controls for the complete HVAC systems. [Dual redundant power supplies (normal ac and safe ac) shall be provided for systems requiring 100% standby plant, including mechanical cooling.] 9.8.1.15 Inspection, testing and commissioning In conjunction with the KNOC, the Bidder shall carry out all necessary inspections as the work progresses, and rectify defects as they are identified. All HVAC systems and components shall be tested and commissioned by an independent specialist firm of Commissioning Engineers, on behalf of the Bidder. Systems shall be completed and tested to comply with the timescale required for the main plant installation and testing. The results of tests shall be submitted to the KNOC for approval, and included in the Operating and Maintenance manuals to be prepared by the Bidder. Operating and Maintenance manuals and ‘As constructed’ record drawings shall be prepared by the Bidder as work proceeds, and completed documents and record drawings shall be submitted to the KNOC for approval in the quantity specified. 9.8.1.16 Domestic hot and cold water services The domestic hot and cold water services within the buildings shall comply with the requirements of the relevant international standard - and /or in accordance with local Iraqi codes. All buildings or areas shall be provided with a cold water storage tank of sufficient capacity to meet one day’s consumption for the building or area served. The tanks shall be of GRP insulated construction, locally manufactured, and where possible located within the building envelope to reduce heating in summer. 9-144 KHABAT TPP UNITS 1&2 - VOLUME I
The hot water systems shall be served from local electrical water heaters, with central storage systems being provided only for large buildings with heavy demand for hot water. In addition to domestic/sanitary water services, the Bidder shall include for potable water supplies to emergency wash-down and shower facilities in battery
rooms
and
chemical
areas,
to
HVAC
humidifiers
and
to
central/emergency water chilling systems. The Bidder shall include for all necessary inspection, testing and commissioning, including disinfection, of the complete hot and cold water services installations. 9.9
Sub-bidders The Bidder when submitting his Bid shall provide details of the sub-bidders, or as a minimum a shortlist of the sub-bidders, he proposes to use for the detailed design and construction of the civil works, together with a summary of works of a similar nature for which they have had design and construction responsibility.
9.10
Functional Requirements The design and layout of the civil works shall be directed to providing sufficient working space for plant and personnel, high standards in safety and working conditions for plant and personnel and to ensuring that maintenance of the installation over the life of the plant is minimal. The climatic conditions and Site location shall be taken into account in the design to meet these requirements. The Bidder shall also ensure in his designs that noise limits for operational plant shall not exceed those specified.
9.11
Record Drawings ‘As constructed’ record drawings shall be prepared by the Bidder as work proceeds and completed record drawings shall be submitted to the KNOC for approval in the quantity specified. Design and construction drawings prepared by CAD shall be made available and updated as the ‘as-constructed’ drawings also in electronic form on CD or DVD disks together with any software and license necessary for viewing and processing them. Three sets of record 9-145 KHABAT TPP UNITS 1&2 - VOLUME I
drawings on Civil Works shall be provided.
9-146 KHABAT TPP UNITS 1&2 - VOLUME I
10
QUALITY CONTROL, INSPECTION AND TESTING
10.1
General The whole of plant covered by this Contract will be subject to inspection and test by KNOC during manufacture, erection and on completion. The Bidder’s costs associated with all tests and inspection shall be borne by the Bidder. The Bidder and appointed subbidders and Bidders are required to comply with the minimum requirements for quality assurance and quality control (inspection and tests) to be applied to goods and services as detailed below. The Bidder and his nominated subbidders shall work to defined quality assurance program compliant with ISO 9001. The Bidder shall list the applicable specifications which will be used as the basis of the quality level(s) proposed for his own, his subBidders and the Bidders scope of supply. The Bidder shall supply the results of any recent audits and approvals held. The Bidder shall have sole responsibility for ensuring compliance with the overall quality requirements of the Works, and shall ensure that subbidder’s implementation of those quality control activities that are appropriate to the extent and nature of their supply. The information supplied in response to the Quality Assurance requirements shall be deemed as part of the quality assurance arrangement and when agreed and accepted by the KNOC shall form an integral part of the Contract. The Bidder shall where required by the contract or other regulatory requirements, appoint an approved body to carry out an independent design, inspection and test audit. The Bidder shall establish and maintain a documented inspection system capable of producing objective evidence that all materials; manufactured parts and assemblies comply with the quality requirements of the Contract. The Bidder shall establish a written procedure to identify and disposition of any deviations identified during the course of manufacture, inspection and test 10-1 KHABAT TPP UNITS 1&2 - VOLUME I
etc. The Bidder and his nominated subbidders may be subject to quality audit by KNOC. The Bidder shall give all necessary help and assistance to KNOC in carrying out such a quality assurance audit. Such audits may take place during the tender evaluation period. 10.2
Extent of Work The Bidder shall define in the Schedule the items within his extent of work; those items to be sub-contracted and state the specifications to be used for each. KNOC will define which items will require Quality Plans (Inspection and Test Plans). The Bidder shall identify the names and locations of the Bidders of all materials, equipment and services including the locations of companies within his own group of companies. The Bidder's quality system shall include as a minimum, procedures used for controlling the following functions. A.
Inclusion on purchase orders of the necessary technical inspection and test details to meet the specified requirements and of the Engineer's right of involvement at the Bidder’s, subbidders’ and Bidders’ works.
B. Availability at inspection points of all documentation required to perform the function B-1 Document control shall issue current drawings and procedures and ensure that all superseded documents are removed. C.
Maintenance and calibration of suitable inspection and test equipment.
D.
Incoming, in process and final inspection and inspection of packing and marking.
E.
Means of identifying inspection status throughout manufacture.
F.
Means of identifying and isolating raw materials and components not conforming to the Contract.
G. Provision of a written procedure to identify and disposition any requested deviations to the applicable national standards and specifications mentioned in the contract specification. All such items shall be reported to KNOC via a non-conformance report. 10-2 KHABAT TPP UNITS 1&2 - VOLUME I
H. 10.3
Provision of complete inspection and test records.
Document Submission The Bidder shall submit project quality assurance(management) program(or plan) for review, in accordance with the requirements described in this specification and the relevant requirements of ISO 9001 and the Bid documents.
Also, the Bidder submits any current quality system certificate
issued by authorized certification bodies with quality assurance program, for information. Any comments of KNOC shall be cleared during the evaluation periods. Within 30 days after contract award, the Bidder shall submit project quality assurance(management) program(or plan) according to the requirements of this specification and relevant ISO 9001 requirements, for review of KNOC. The Bidder shall review, amend and re-submit project quality assurance (management) program(plan) as necessary during the Contract. During the course of the Contract the KNOC reserves the right to monitor (audit) the implementation of the Bidder’s quality assurance program(plan). The Bidder shall submit for review, within 30 days of the Contract award a quality plan (inspection and test plans) defining the program of quality control and inspection activities which he or his subbidders/Bidders will perform in order to ensure that the procurement, manufacture and completion of the materials, equipment and plant complies with the specified requirements. All submitted documents shall clearly identify the manufacturer and the item/sub-item of plant to which they apply. The quality plan may be of any form to suit the Bidder's system, but it shall as a minimum: A.
Indicate each inspection and test point and its relative location in the production cycle including incoming, packing and site inspections.
B.
Indicate where subbidders' services will be employed (eg subbidder NDT or heat treatment).
10-3 KHABAT TPP UNITS 1&2 - VOLUME I
C.
Identify the characteristics to be inspected, examined, and tested at each point and reference drawings, procedures and acceptance criteria to be used.
D.
Indicate the inspection, test and hold points established by the Bidder, subbidder
and
Bidder,
which
require
verification
of
selected
characteristics of a document, item or process before this work can proceed. E.
Allow for witness, hold and review points to be established by KNOC, which require his verification of selected characteristics of a document, item or process before this work can proceed.
F.
Define or refer to sampling plans if proposed and where they will be used.
G. Where applicable, specify where lots or batches will be used. KNOC will indicate the inspection requirements on the agreed inspection program in accordance with the following: 1) Hold point - requires a mandatory inspection by KNOC. This inspection or test shall be witnessed by KNOC and further progress in manufacture shall not be made until the plant is approved by KNOC. 2) Witness point - inspection or test of material may be carried out by KNOC at his discretion. 3) Document review - certification of material and functional test shall be approved by KNOC before despatch from the works. Independently, the requirements of the Third Party Inspectorate shall be indicated in a similar manner prior to the submission of the Inspection Plan to KNOC, for his approval. The Bidder shall forward for review within 60 days of contract award for applicable items of equipment identified within quality plans, duplicate copies of: A. Special process procedures covering the welding, heat treatment and non-destructive examinations of all pressure retaining and loading bearing fabrication welds and major castings including repair procedures. Procedures must include qualification records and acceptance criteria where applicable. B. Inspection procedures for components and test procedures for sub10-4 KHABAT TPP UNITS 1&2 - VOLUME I
assemblies and complete assembly of the turbine shall be submitted to KNOC for approval before assembly commences. C. Test procedures for the witness testing of generators, excitation system, transformers, motors, frequency converters, HV and MV cables, HV, MV, and LV switchgear, UPS and DC systems, protection equipment and circuit breakers and frequency converters. D. Test procedures for the witness testing central and local control panels, SCADA and PCS equipment E. Test procedures for the witness testing pumps, compressors and automated valves. F. Purchase orders (un-priced) complete with technical specification and data sheets. 10.4
Inspection Notification and Right of Access In order to verify compliance with engineering procurement, manufacturing requirements and programs, KNOC shall have access at all reasonable times, to all places where materials or equipment are being prepared or manufactured and tested, including the works of the Bidder, subbidders or Bidders of raw materials. The Bidder shall advise KNOC of the readiness of inspection at least 30 working days prior to a nominated witness or hold point.
Work shall not
proceed beyond a hold point without the written agreement of the KNOC or his nominated representative. A common form of notification will be developed and agreed for general use on the contract. Before giving such notice the Bidder is required to have completed all his internal controls, including that relative to the notification point and to have available documentation to that effect for the Engineer to review. Request for waiver from contract quality requirements shall be made by the Bidder to KNOC, as soon as it is established that an item of equipment as designed, or in manufacture, cannot be made to comply with a particular specified requirement. The subject item of equipment shall not be offered for final inspection until such waiver requests have been approved by KNOC. 10.5
Inspection and Tests 10-5 KHABAT TPP UNITS 1&2 - VOLUME I
Inspection of materials or equipment may be made by KNOC and could include the following activities: A.
Evaluation of the Bidder's system and approval of the quality plans.
B.
Periodic monitoring to confirm the effectiveness of and the Bidder's, subbidders’ and Bidders’ compliance with the established quality system procedures, inspection and test plans and inspection and test instructions.
C.
Witnessing of inspections and tests and/or verification of inspection records to be carried out at the Engineer's discretion covering:
Compliance of raw material with specified requirements.
Compliance of manufactured parts, assemblies and final items with
Specifications, drawings; standards and good engineering practice.
Periodic inspection of Bidder's design, manufacturing, installation work and the production of progress reports.
Witnessing of inspections and tests.
Packing for shipment including check for completeness of shipment, handling requirements, and case markings and identification.
The Bidder shall keep KNOC informed in advance of the time of starting and of the progress of the work in its various stages so that arrangements can be made for inspection and for test. The Bidder shall plan the performance of inspection and tests so as to avoid the delaying of the work. All of the required inspections and tests shall be made at the Bidder's expense, including the cost of all samples used. The Bidder shall be responsible for any additional costs incurred by KNOC arising from the postponement, reinspection or additional inspections or visits attributable to the Bidder, subbidders or Bidders’ performance. The Bidder shall also provide, without charge, all reasonable facilities and assistance for the safety and convenience of KNOC in the performance of his duties. If the plant or any portion thereof fails under test to give the required performance, such further tests which are considered necessary by KNOC shall be carried out by the Bidder and the whole cost of the repeated tests 10-6 KHABAT TPP UNITS 1&2 - VOLUME I
shall be borne by the Bidder. This also applies to tests carried out at subbidder’s works. 10.6
Non-conformances Non-conformances identified by KNOC shall be notified to the Bidder by issue of KNOC’s Non-Conformance Report. The Bidder shall receive and action all non-conformance reports and re-inspection shall not be notified until the completed non-conformance report, together with any applicable re-work or concession application, have been accepted by KNOC. Where applicable, rejection of materials, equipment and/or components will be made as promptly as practicable following any inspection or test involvement by KNOC. Failure to inspect and or reject materials, equipment and/or components shall neither relieve the Bidder from responsibility for such items which may not be in accordance with the specified requirements, nor impose liability for them on KNOC. The Bidder and subbidders quality assurance program shall identify and isolate raw materials and components not conforming to the Design Book. All such items shall be reported to the KNOC via a non-conformance report. Approval of a concession application is the prerogative of KNOC and approval of a particular case shall not set precedent. KNOC shall have complete authority to accept or reject any equipment or part thereof considered unsatisfactory and/or not in accordance with the contract requirements. The witness of any inspection and tests by KNOC of any components or lots thereof does not relieve the Bidder of any responsibility whatever regarding defects or other failures which may be found before the end of the warranty period.
10.7
Quality Control Records, Certificates and Certificates of Conformance At the end of each visit to a manufacturer to carry out quality control activity, KNOC’s Representative will complete a Quality Control Record and hand one copy to a responsible representative of the Manufacturer. 10-7 KHABAT TPP UNITS 1&2 - VOLUME I
The Quality Control Record (QCR) will identify the item inspected, the stage of manufacture, and the nature of the QC carried out, and will list all points which require remedial action by the manufacturer, before the subject item can be released. When each item of equipment is ready for dispatch from the place of manufacture and KNOC has verified compliance with specified requirements up to that point, a Quality Control Certificate will be issued to the Bidder. The Quality Control Certificate (QCC) will identify the item to which it applies and will release that item from KNOC’s control only. The QCC does not constitute any form of acceptance of the item by either KNOC or the Representative. The Bidder shall provide a Certificate of Conformance confirming compliance with the Contract requirements and as detailed in the manufacturing record data book. Sets of all test records, test certificates and performance curves, whether or not they have been witnessed by KNOC, shall be supplied for all tests carried out in accordance with the provisions of this Contract. Sets of all test certificates shall be endorsed with sufficient information to identify the material or equipment to which the certificates refer, and shall carry in the top right hand corner the following reference: KNOC’s name Project title KNOC’s reference number. All test documentation shall be in the English language. No materials or equipment shall be shipped to the Site until all tests, analysis and inspections have been made and the Bidder's Certificate of Conformance has been reviewed and released by KNOC; or unless otherwise agreed by KNOC. 10-8 KHABAT TPP UNITS 1&2 - VOLUME I
10.8
Specific Tests and Inspections Refer to Volume 2, Schedule G for details of specific tests and inspections.
10-9 KHABAT TPP UNITS 1&2 - VOLUME I
11
COMMISSIONING, START-UP AND TESTING
11.1
General The Bidder shall be responsible for the functional testing, pre-commissioning, commissioning, reliability testing and performance testing of the Plant including ancillary equipment. The reliability tests shall be carried out after the Plant performance test. Upon completion of the reliability test, and to the KNOC’s satisfaction that equipment operation and reliability has fulfilled the Contract requirements, the equipment shall be declared ready for the issue of the Operational Acceptance Certificate. For the purposes of the Contract, pre-commissioning shall be defined as that period when individual mechanical and electrical plant items, and control and instrumentation systems are checked and proved, and activities such as cleaning of pipe work and tank internals are carried out. For the purposes of the Contract, Commissioning shall be defined as those activities which require operation of substantial amounts of equipment on a coordinated basis, in a manner which is generally similar to the operation of the plant in commercial service. Commissioning shall hence include activities such as steam purging or rolling the turbine. Commissioning shall also include the specified tests on completion. The Bidder shall be responsible for providing all the necessary permanent and temporary equipment, materials, consumables (excluding fuel) and services to meet his commitments with regard to the commissioning and testing phases of the work, whether or not the tests are specifically referred to in this Specification. The Bidder shall provide and install temporary instrumentation for the performance testing.
All temporary instruments shall be of an accuracy
class appropriate for performance testing. Permanently installed instruments may be used during the performance test for secondary measurements as mutually agreed. The complete performance test methodology, including detailed testing procedures and test program, accuracy of measurement, test instrumentation etc. shall be provided by the Bidder at least 6 months prior to testing for review and approval.
11-1 KHABAT TPP UNITS 1&2 - VOLUME I
11.1.1
Staffing During pre-commissioning the Bidder shall provide all necessary supervisory and operating staff. The only involvement of the MOE/KNOC’s staff will be in accordance with the training and instruction as in this Specification. During the commissioning phase the MOE’s operating staff will operate plant and equipment under the supervision of the Bidder’s supervisors. The Bidder shall have satisfied himself as to the capability of the MOE’s operators to carry out such operations as he may direct and shall remain responsible for the successful performance of such operations. Throughout the whole of the Commissioning Period the Bidder shall provide suitably qualified and experienced operating staff, who shall instruct the MOE’s staff in the correct operating procedures. The Bidder shall provide a team of suitably qualified and experienced engineers and technicians to pre-commission and commission the overall plant. The Bidder shall also ensure that a suitably qualified commissioning engineer from the respective manufacturer’s own service organization shall visit the site to check the erection or installation of each significant plant item, and to supervise the commissioning of the plant item, until the basic functioning of the item has been demonstrated to the KNOC’s satisfaction.
11.2
Precommissioning The Bidder shall be responsible for performing mechanical testing and functional testing of all the plant components and systems to confirm compliance with design and operating criteria. The Bidder shall also be responsible for performing mechanical testing and functional testing of all the plant components and systems to confirm compliance with design and operating criteria. During this period the Bidder shall undertake all installation checks, preliminary mechanical and electrical checks, pressure testing, flushing and cleaning of equipment and pipework, proving the integrity of all connections (mechanical and electrical), safety systems and verification that all plant is functionally complete. Where components form part of a system, then each component comprising that system shall be similarly inspected and tested prior to placing the system into service. Static tests to demonstrate interactive operation of components within the system shall also be completed prior to charging or energizing the system for the first time. 11-2 KHABAT TPP UNITS 1&2 - VOLUME I
The Bidder shall also be responsible for producing a Quality Plan to detail all test requirements for the plant. KNOC shall be given the opportunity to witness all such testing and inspections. All checks, inspections and test activities and results shall be logged by the Bidder on suitable pro formas and shall be available for inspection by KNOC at all times during the course of the Works. Copies of this documentation shall be passed to KNOC on completion of the Works. The Bidder shall provide KNOC with a list of all items that are incomplete and/or not fit for purpose and for which remedial action has to be taken. The Bidder shall prepare a detailed schedule for testing and commissioning of all equipment, systems and subsystems within his scope of supply. This schedule shall be submitted to KNOC at least 12 months prior to testing. Pre-commissioning activities shall include, but not be limited to, the following. 11.2.1
Boiler A pre-commissioning test program for the completely assembled boiler shall be agreed with and approved by KNOC and shall at least include the following: A.
The boiler unit, including the superheaters and economizers complete with tubes, mountings and fittings shall be tested at a predetermined and agreed hydraulic pressure.
B.
The boiler unit casing from the furnace to the economizer outlet shall be tested for gas tightness.
C.
The precommissioning activities associated with the sootblowing system including, but not limited to, the following: 1) manually operate each individual sootblower to ensure freedom of movement and, whilst this is being carried out, check the blowing positions 2) check the rotation of the blower and valve motors together with overload protection. 3) start each sootblower, using the local control button and perform initial operating checks.
D.
The fire protection system shall be checked to ensure that each section of fire protection equipment is available to protect the main plant before the plant commissioning is undertaken. The precommissioning activities shall
11-3 KHABAT TPP UNITS 1&2 - VOLUME I
stretch to the fire protection system and include, but not be limited to, the following: 1) demonstrate that each system is capable of initiating alarms 2) ensure correct indication of zones 3) ensure that the design criteria for water pressure, flow and coverage are met E.
The precommissioning activities associated with the gas and air system including, but not limited to, the following: 1) air heater temperature indicator and thermostat operation/settings are proven 2) the position and calibration of the air heater fire detecting thermocouples, along with alarm operation and initiating values, are checked 3) verification that all air heater seals are correctly fitted and checked for freedom of movement 4) air heater oil tank level indicator is to be checked to ensure correct fitting 5) ensure that the air heater lubricating oil system is flushed. The oil cooler shall only be introduced following the flushing 6) ensure that the air heater main and washing drive couplings are connected and checked for alignment 7) ensure that the lubricating oil system is flushed thoroughly for the draught plant (CID, FD and GR fans) 8) the operation of all local and remote instruments, interlock devices, and alarm inputs shall be checked 9) fans shall be run initially to check rotation, overload protection, alignment and balancing.
11.2.2
Turbine A pre-commissioning test program for the completely assembled turbine shall be agreed with and approved by KNOC and shall at least include the following: A.
A check of the thickness of all turbine casing and main steam pipework lagging.
B.
Demonstration that the rotor differential expansion equipment settings has been correctly set up and recorded.
C.
All turbine valve power piston travel is checked and recorded. 11-4 KHABAT TPP UNITS 1&2 - VOLUME I
D.
Turbine valves are checked for closure; confirmed by an external reference mark.
E.
Pilot valves and linkages are checked and recorded for freedom and travel.
F.
Ensure ac and dc flushing oil pumps both start automatically and, with simulated main oil pump pressures and flows, check ac and dc flushing pumps stop automatically and Ensure correct direction of pumps and overload protection operation
G. Prove the manual control of the ac and dc flushing pumps. H.
With the ac pump in service, prove the dc pump does not start in automatic control mode. Demonstrate that the dc pump then starts automatically when the ac pump is stopped.
I.
Demonstrate that jacking oil pumps will not start on low lubricating oil pressure, low seal oil pressure, or a turbine shaft speed greater than 100 rpm by injecting appropriate signals into the control system.
J.
Demonstrate that the jacking oil pumps start automatically when the lubricating oil pressure is normal and shaft speed below 100 rpm and confirm the direction of flow and overload protection operation
11.2.3
Generator A pre-commissioning test program for the completely assembled generator shall be agreed with and approved by KNOC and shall at least include the following: A.
Assembly check.
The component parts of the generator when re-
assembled on site shall be inspected and checked to ensure that all parts are properly fitted one
to another and that the overall dimensions,
clearances and tolerances are correct. B.
Dry out. Before any electrical tests take place the insulation polarization index and insulation resistance of the stator winding shall be measured against time with results submitted to KNOC, and if deemed necessary the generator shall be dried out.
The method of drying out shall be to
approval. 11.2.4
Condenser A pre-commissioning test program for the completely assembled condenser shall be agreed with and approved by KNOC. The test program shall at lest include the following: 11-5 KHABAT TPP UNITS 1&2 - VOLUME I
A.
The condenser shall be subject to a standing water test by filling the steam space with water for a period of 24 hours.
B.
The cooling water inlet and outlet valves, local and remote operation, shall be demonstrated.
11.2.5
Control and instrumentation installation and precommissioning Installation and pre-commissioning of all instrumentation shall be generally in accordance with the relevant international code & standard. Test documents shall be produced and shall include checklists to be witnessed by KNOC. These test documents shall contain agreed acceptance criteria. The Bidder shall record the result of all calibration checks and loop tests on suitable check sheets such as those examples given in the relevant international code & standard. Commissioning shall be achieved in the following stages: A.
Calibration and function tests prior to operation. These shall include: 1) Calibration of complete loops. 2) Performance check using simulated input/output conditions. 3) Sequence and interlock equipment proving. 4) Control loop functions using simulated conditions. 5) Software testing.
B.
Cold plant interface tests.
These shall be carried out with equipment connected to the plant and shall as far as possible demonstrate that plant may be controlled safely and to Specification. 11.2.6
Turbine governing equipment A pre-commissioning test program for the complete governing system shall be agreed with and approved by KNOC and shall at least include that the governor actuator, valves and components be subjected to routine tests to demonstrate functional characteristics. Load/speed electronic governing equipment - static characteristics of the amplifier, actuator and servomotor shall be obtained from factory tests.
11.2.7
Power transformer The Bidder shall submit a schedule of tests to be carried out at site to include the following as a minimum. 11-6 KHABAT TPP UNITS 1&2 - VOLUME I
11.2.8
A.
Vector group and voltage ratio test.
B.
On load tap changer test.
C.
Local control panel sequence test.
D.
Oil leakage test.
E.
Mechanical protective relay test.
Protective relaying Details of all necessary pre-energization and commissioning tests shall be submitted for approval prior to the tests being performed, together with any supporting explanatory documentation such as ‘Installation, Operation and Maintenance manuals’. An opportunity shall be provided for KNOC to witness the tests.
11.2.9
Switchboards, cubicles, relay panels, marshalling boxes, enclosures and ancillary electrical equipment The Bidder shall submit a schedule of tests to be carried out at site to include the following as a minimum. A.
Check tightness/security of all connections.
B.
Function test all circuits if applicable.
C.
Insulation testing of wiring.
D.
Check correct glanding of cables.
E.
Confirm earthing correct.
11.2.10 Low voltage switchgear The Bidder shall submit a schedule of tests to be carried out at site to include the following as a minimum. A.
Routine high voltage tests.
B.
Insulation resistance tests.
C.
Check for security of all connections.
D.
Continuity tests.
E.
Function testing of each circuit to ensure correct operation including interlocks, tripping and closing, indications and alarms.
F.
Phasing out and synchronising tests.
G. Primary injection of all protection and metering circuits to check for satisfactory operation. H.
Secondary injection tests on relays and instruments to check correct operation. 11-7 KHABAT TPP UNITS 1&2 - VOLUME I
I.
Tests to check magnetization curves and direction tests, polarity and resistance of current transformers.
J.
CT and VT ratio tests.
K.
Secondary injection of voltage transformer circuits.
L.
On load checks of all protection, indicating and metering circuits.
M. Confirm adequate glanding and cable supports. N.
Confirm earthing correct.
11.2.11 Motors The Bidder shall submit a schedule of tests to be carried out at site to include the following as a minimum. A.
Insulation resistance measurement.
B.
Direction of rotation.
C.
Measurement of no load current.
D.
Check auxiliaries and monitoring/instrumentation for correct operation.
E.
Confirm setting and operation of thermal overload protection.
11.2.12 Electrical equipment for hazardous areas The installation of all equipment for use in hazardous areas shall be checked to be in accordance with the manufacturer’s recommendations and contract drawings. 11.2.13 1-30 kV XLPE cable and accessories All cables shall be tested following installation in accordance with the requirements of IEC 60502. A.
Voltage withstand test. Each laid and jointed cable shall be subjected to a voltage withstand test. The voltage shall be increased gradually and maintained for one minute at 5 kV ac rms between each conductor and the remaining conductors connected to the armour and earthed. No breakdown of insulation shall occur.
B.
Pressure (high pot) test Due to the lack of suitable ac cable test equipment in Iraq, a reduced voltage dc test will be acceptable. There shall be a 1000V megger test recorded, followed by a 15 minute High Pot test with leakage current recorded every minute, and a final comparison megger test. The value of
11-8 KHABAT TPP UNITS 1&2 - VOLUME I
the test voltage will depend on the cable used and be confirmed by the Owners Engineer. 11.2.14 Auxiliary multicore cables The Bidder shall submit a schedule of tests to be carried out at site to include the following as a minimum. A.
Continuity. Each length of cable shall be tested for continuity together with point to point confirmation.
B.
Insulation resistance. The insulation resistance of each length of cable shall be measured between each conductor and other conductors connected to the armour. Following the application of 500 V dc for one minute, the measured value shall not be less than the original value.
C.
Conductor resistance. The resistance of each conductor shall be measured and recorded.
11.3
Commissioning The Bidder shall be responsible for carrying out all the commissioning work associated with bringing the Plant to a condition where it is ready to undergo its performance and reliability tests. Prior to the start of commissioning, the Bidder shall ensure that KNOC have been provided with the latest edition of all relevant documents and drawings. Details of all necessary pre-energization and commissioning tests shall be submitted for approval prior to the tests being performed, together with any supporting explanatory documentation such as draft ‘Installation, Operation and Maintenance manuals’. An opportunity shall be provided for KNOC to witness the tests. Once the component or system is charged, energized or otherwise made live, the Bidder shall conduct further tests to demonstrate that the system and its constituent components function collectively as designed, that individual components operate at varying loads under steady state conditions within their stated operating parameters, and that the components and system respond correctly to transient conditions. The Bidder shall undertake whatever adjustments are necessary to achieve the best level of the Plant reliability, capacity and performances. After the completion of commissioning of each plant item or system, the Bidder shall submit to KNOC a commissioning report for the plant item or system, including the completed commissioning check lists. The report shall summarize the commissioning procedure followed, 11-9 KHABAT TPP UNITS 1&2 - VOLUME I
describe any adjustments or modifications made to the plant, and shall include a statement that the relevant sections of the draft instruction manuals are correct and appropriate, or alternatively include recommendations for corrections to the manuals. The commissioning report shall include all measurements settings and adjustments made to the plant during the erection, pre-commissioning and commissioning periods. These shall include pipe work spring settings, alarm settings, valve adjustments and similar data. Commissioning activities shall include, but not be limited to, the following. 11.3.1
Oil supply systems The oil supply systems shall be tested to demonstrate satisfactory fuel pressure/flow control under all operating conditions including start-up, full load rejection and transient conditions.
11.3.2
Boiler A commissioning test program for the complete boiler shall be agreed with and approved by KNOC and shall at least include the following: A.
The commissioning activities associated with the sootblowing system, with boiler at least operating at 50 per cent load, including but not limited to, the following 1) initiate steam warming and charge the pressure reducing valves. Record pressures 2) confirm that system relief valve is not lifting 3) ensure that reheat steam supply non-return valve is not passing steam 4) confirm that, with section valves wide open and drain valves shut, steam system is at correct pressure with no evidence of pressure steam leakage 5) initially select the air heater zone, initiate the sootblowing system and check the individual sootblower steam pressure and compare with original cold set values 6) check and record blowing time for each sootblower 7) observe operation of sootblowers checking for evidence of interrupted travel 8) select the other boiler zones in turn and repeat the above three steps.
11-10 KHABAT TPP UNITS 1&2 - VOLUME I
B.
The commissioning activities associated with the burner management system including, but not limited to, the following 1) start up oil valves to be adjusted, with less than 25 per cent MCR airflow, to obtain desired oil pressure 2) adjust controllers as necessary to obtain 100 per cent settings then select start up valve to automatic 3) adjust controllers to obtain stable signal between desired and measured values of start up valve 4) repeat tests until optimum steps are obtained 5) with airflow exceeding 25 per cent MCR and CID fans on automatic control, adjust settings to obtain satisfactory oil/airflow ratio 6) increase oil input and airflow until approximately 40 per cent MCR airflow is reached. Re-establish correct oil/airflow ratio 7) adjust fuel air ratio and select oil valve to automatic control 8) test until optimum settings have been obtained.
C.
The commissioning activities associated with the gas and air system including, but not limited to, the following: 1) air inlet and outlet, gas inlet and outlet bypass damper control settings 2) ensure that the air heater driving motor can only be started when lubricating oil flow has been established by pressure switch operation 3) demonstration that the driving motor is interlocked with air heater inlet and gas outlet dampers, such that the dampers cannot be opened until the air heater rotor is turning 4) ensure that the fans are prevented from starting unless the induction regulator is in the starting position 5) demonstrate that the fans can be stopped or prevented from starting if the supply voltage falls below 70 per cent of nominal 6) show that the speed is below 500 rpm for starting.
11.3.3
Generator A commissioning test program for the completely assembled generator shall be agreed with and approved by KNOC and shall at least include the following: A.
Winding resistances. Cold stator and rotor winding resistances and corresponding temperatures shall be measured. The rotor winding resistance shall be measured before and after running tests. 11-11 KHABAT TPP UNITS 1&2 - VOLUME I
B.
Characteristic curves. Generator open circuit and short circuit curves shall be measured and plotted.
C.
Temperature rise. Temperature rise tests shall be carried out at rated output.
The test shall be run until steady temperatures are obtained. These tests can be combined with the overall efficiency tests. 11.3.4
Excitation system Tests shall be carried out on each machine to demonstrate that the equipment performs correctly and as specified, and that stability margins are adequate. A commissioning test program for the completely assembled excitation equipment shall be agreed with and approved by KNOC and shall at least include the following: A.
Verify trigger pulse sequences, triggering current magnitude and rate of rise applied to thyristors.
B.
Demonstrate that phase currents to thyristor rectifier are balanced over operating range and that parallel connected thyristors share current adequately.
C.
Determine settings for automatic regulator adjustable controls for test performance with generator on open circuit, and demonstrate, for example by step response or harmonic response tests, the stability margin over the full operating range of generator terminal voltage and frequency.
D.
Demonstrate start up and shut down sequences.
E.
Demonstrate operation of limiters and set at required operating point.
F.
Demonstrate generator steady state performance and verify margin between underexcitation limiter setting and theoretical steady state stability limit.
G. Demonstrate operation of power system stabilizer. H.
Demonstrate VAr sharing between generators.
I.
demonstrate performance on full load rejection;
J.
Demonstrate transfer between automatic and manual control by simulated fault and by deliberate selection, and transfer between manual and automatic control.
K.
Demonstrate operation in manual control.
L.
Demonstrate all control functions, alarms and protection circuits. 11-12 KHABAT TPP UNITS 1&2 - VOLUME I
M. Temperature rise test at rated generator load, over-excited to verify cooling of the excitation converters and transformer. 11.3.5
Generator main and neutral earthing connections The Bidder shall submit a schedule of tests to be carried out at site to include the following as a minimum. A.
Routine high voltage tests in accordance with the appropriate standard.
B.
Checking of security, torque settings and resistance of all busbar connections, connections to equipment and flexible connections in accordance with the manufacturers instructions.
C.
Check operation of air pressurizing equipment including operation of redundant systems.
D.
Check operation of pressure monitoring equipment including local indications, alarms and remote alarms.
11.3.6
Current transformers The following tests shall be carried out as a minimum requirement.
11.3.7
A.
Accuracy and burden check.
B.
Ratio check.
C.
Polarity check.
D.
Magnetizing curve.
E.
Measurement of resistance.
Voltage transformers The following tests shall be carried out as a minimum requirement:
11.3.8
A.
Accuracy and burden check.
B.
Ratio check.
C.
Polarity check.
Control and instrumentation installation and commissioning Commissioning of all instrumentation shall be generally in accordance with the relevant international code & standards. Test documents shall be produced and shall include checklists to be witnessed by KNOC. These test documents shall contain agreed acceptance criteria. The Bidder shall record the result of all calibration checks and loop tests on suitable check sheets such as those examples given in the relevant international code & standards. 11-13 KHABAT TPP UNITS 1&2 - VOLUME I
Commissioning shall be achieved generally in accordance with hot plant tests. These shall be carried out in conjunction with the plant in operation. They shall include on-line tests to demonstrate that all control and plant monitoring equipment are within specification in an operating environment. 11.3.9
Turbine governing equipment A commissioning test program for the complete governing system shall be agreed with and approved by KNOC and shall at least include combined tests on the governor actuator and main actuating valve. The tests shall demonstrate performance of the equipment for the following characteristics: A.
Range of external command signal
B.
Dead bands and dead times
C.
Inaccuracies
D.
Range of permanent speed droop
E.
Temporary speed droop
F.
Time constant of damping device
G. Derivative of time constant of the speed sensor H.
Stroke of main regulating valve
I.
Servomotor closing and opening time
J.
Servomotor response time
K.
Promptitude time constant
L.
‘Fail safe’ features
M. Insensitivity to change in hydraulic pressure N.
Performance of load limiting device.
11.3.10 Turbine A commissioning test program for the complete turbine oil system shall be agreed with and approved by KNOC and shall at least include the following: A.
The complete turbine oil service system shall, if required by KNOC, be tested with oil and auxiliary cooling water pressures at a pre-determined and agreed test level.
B.
The Bidder shall state the proposed method for testing the operation of the bolts or rings of the turbine emergency governors whilst the sets are on-load.
C.
Tests shall be carried out to demonstrate starting after 8 hour and 36 hour shutdowns.
11-14 KHABAT TPP UNITS 1&2 - VOLUME I
D.
Demonstrate automatic starting of the ac flushing oil pump and dc flushing oil pump by reducing the turbine speed from 3000 rpm to the appropriate levels.
E.
Demonstrate automatic starting of the ac seal oil pump and dc seal oil pump by reducing the turbine speed from 3000 rpm to the appropriate levels.
F.
After each of the tests in d. and e. raise the turbine speed back to 3000 rpm to check the respective ac and dc flushing and seal oil pump are turned off automatically.
11.3.11 Pumps The oil and water sides of all pumps shall, if required by KNOC, be tested with oil and water pressures at a pre-determined and agreed test level. 11.3.12 Site acceptance tests When the hot plant testing by the Bidder is completed, the Bidder shall be required to demonstrate the functionality of the plant according to a repeat of the factory acceptance tests. KNOC will witness these tests. 11.4
Testing
11.4.1
Tests on completion KNOC will give written permission for the Plant to be run for a preliminary period of operation during which time the Bidder shall demonstrate, to the KNOC’s satisfaction, that the Plant can be operated in accordance with the requirements of the Specification and to prove correct operation of all manual and automatic controls, automatic sequences and safety equipment, etc. The Bidder shall also demonstrate that the boiler and the turbine are capable of stable and continuous automatic operation at full capacity (steam turbine valves wide open) and also down to minimum stable load of [30 percent] of the turbine generator rating. The correct functioning of all alarms and trips shall be demonstrated under operating conditions. Also, the Bidder is to undertake the following tests prior to commercial operation and take-over to prove that both the Plant are fit for purpose in accordance with the Specification. The scope of tests shall include, but not be limited to, the following:
11-15 KHABAT TPP UNITS 1&2 - VOLUME I
A.
Demonstration of starting, shutdown and transient characteristics under hot, warm and cold conditions using the methods described in the Bidder’s draft instruction manuals.
B.
The plant may be shut-down satisfactorily under emergency conditions using the methods described in the Bidder’s draft instruction manual.
C.
A series of sudden load rejection tests to determine the pressure rises in the high pressure system when the turbo-generator is under governor control
D.
A series of sudden load rejection tests to determine the momentary overspeeds and pressure rises in the high pressure system when the turbo-generator is under governor control
E.
Proving tests of all control equipment, safety and protection devices
F.
Demonstration of water and steam purity
G. Undertaking on-line maintenance of all equipment where on-line maintenance is specified, such as change over of filters H.
Performance tests
I.
Reliability test
J.
Environmental tests.
The Bidder shall draw up a program for each of the above tests which shall be submitted to KNOC for approval before commencement of the tests. 11.4.1.1 General As soon as practicable after the satisfactory completion of the Plant commissioning, the Bidder shall carry out performance tests to demonstrate that the boiler complies with the performance guarantees relating to boiler efficiency, maximum steam production, boiler outlet steam conditions, etc., whilst also complying with all environmental noise and emission limits. The Bidder shall also carry out performance tests to demonstrate that the turbine complies with the performance guarantees relating to gross generator output, gross turbine heat rate, etc., whilst also complying with all environmental noise and emission limits. The method used to determine boiler performance shall be in accordance with ASME PTC 4-1998. Steam properties shall be determined in accordance with ASME steam tables based on IAPWS-IF97. Test procedures shall be provided by the Bidder not later than 6 months prior to testing. Final Test Procedures 11-16 KHABAT TPP UNITS 1&2 - VOLUME I
shall be subject to agreement with KNOC. The method used to determine steam turbine performance shall be in accordance with ASME performance test codes, such as PTC 6 full test-1996. Steam properties shall be determined in accordance with ASME steam tables based on IAPWS-IF97. Test procedures shall be provided by the Bidder not later than 6 months prior to testing. Final Test Procedures shall be subject to agreement with KNOC. The Bidder must inform KNOC 15 days in advance of any test. A preliminary test report shall be issued to KNOC not more than 1 week after the completion of the performance tests. The final test report, including the results calculated with the laboratory test fuel analysis, shall be issued to KNOC no later than 4 weeks after the completion of the performance tests. All tests and reports shall be at the Bidder’s expense. 11.4.1.2 Instruments and tolerances All temporary test instrumentation shall be calibrated using standard reference sources or shall have been previously calibrated and certified by independent approved certification authorities not more than 6 months prior to the Performance Test. Prior to the performance tests every instrument required for measurement of test data shall be checked and recalibrated if necessary. Calibration certificates shall be provided for the test instruments at the time of test. The costs involved in preparation of calibration certificates will be to the Bidder’s expense. All instruments used in the performance tests shall be of the standard quality and measurement accuracy detailed in the agreed performance test procedure and test codes. The corrected test results for boiler performance shall not have any tolerance applied to account for instrument measurement uncertainty. Commercial test tolerances will also not be applied to the test result. The Bidders performance guarantee figures shall therefore be quoted without tolerance. 11.4.2
Performance guarantee tests The Performance Test Procedure of the plant shall be a full and detailed procedure based on ASME PTC 46-1996 and in accordance with the procedures, scope and details contained in the Contract. The Performance Test Procedure will be discussed and mutually agreed between the Bidder 11-17 KHABAT TPP UNITS 1&2 - VOLUME I
and KNOC. The test procedure shall include at least the following: A.
Scope of tests
B.
Guiding principles 1) Test dates and timetables 2) Test preparation 3) Test methods 4) Intended modes of operation 5) Test personnel and responsibilities 6) Heat balance diagrams
C.
Test conditions 1) Operating conditions 2) Consistency of test conditions 3) Maximum permissible variations in operating conditions 4) Test duration
D.
Instruments and methods of measurement 1) Definition of test parameters 2) List of test instruments 3) Calibration of test instruments 4) Instrument measuring accuracy 5) Commercial plant instruments 6) Fuel sampling and laboratory analysis details
E.
Computation of test results 1) Data acquisition system log sheets 2) Commercial panel instrument and manual log sheets 3) Frequency of readings 4) Observers and labour 5) Specified requirements and guarantees
F.
Correction philosophy 1) Instrument list and diagram of test measuring points 2) Instrumentation for measuring fuel and steam flows 3) Sample calculation based on design values 4) Measurement uncertainty analysis.
11.4.3
Reliability tests The reliability of the Plant complete with all ancillary plant, equipment and services required for the full, safe and efficient operation, shall be proved by 11-18 KHABAT TPP UNITS 1&2 - VOLUME I
starting automatically, and by running under normal commercial operating conditions, the Plant for a period of ten (10) days without interruption, whilst remaining in full compliance of all environmental restrictions. Should a failure occur in any system, or component of the system, due to, or arising from, faulty design, material or workmanship sufficient to prevent commercial use of the unit, the reliability test period shall restart for the Plant after the Bidder has completely remedied the failure. Minor defects such as instrument faults or equipment faults requiring the operation of standby plant, shall not constitute a failure of the reliability test, provided that the overall plant continues to operate satisfactorily and that the faults are rectified and are not persistent. The onus on proving that any failure or defect is due to causes other than faulty design, material or workmanship shall lie with the Bidder. The equipment will be under the charge of KNOC staff during the reliability test, however the Bidder shall have his approved representatives present as requested by KNOC to supervise the work. The Bidder’s representatives and supervisors shall be responsible for all safe operation of the equipment during the test and before taking over. KNOC staff will not be liable for any problems encountered throughout the testing period. During the test period, the systems shall run continuously without adjustment or repair to the complete satisfaction of KNOC. 11.4.4
Environmental tests During the performance and reliability tests the Bidder shall undertake witnessed noise and emission tests to prove that the Plant meets all relevant noise requirements and environmental emissions limits. The performance test procedure of flue gas desulfurization units shall be a full and detailed procedure based on ASME PTC40-1991 and in accordance with the procedures, scope and details contained in the Contract. The noise measurement equipment shall comply with ANSI S1.4 precision standards. The test methodology shall be in accordance with the international standards. The results of the tests shall be fully reported together with operating conditions of the equipment, noise measurements, instrument locations and instrument details. For work area noise acceptance tests, equivalent continuous levels shall be obtained at a minimum distance of 1 meter from the surface of equipment, 11-19 KHABAT TPP UNITS 1&2 - VOLUME I
acoustic enclosures, or room boundaries. Corrections of any measured noise levels to account for free field effect shall not be applied. Tests will be undertaken on effluent and flue gas emission levels also to ensure compliance with the relevant permitted levels. 11.4.5
Reporting of test results The Bidder shall compute the results of the performance, reliability and efficiency tests expeditiously and not more than one week after the completion of the tests submit to KNOC a preliminary test report in which the test results shall be summarized and explained. The final test report shall be issued to KNOC no later than four weeks after completion of the tests. The general style of presentation and binding of the final report shall match that of the Operating and Maintenance Instructions. All tests and reports shall be at the Bidder’s expense.
11.4.6
Performance worse than guaranteed After the measured or “as-run” test results have been corrected to the specified conditions, the corrected test results will be directly compared with the plant operation guarantee data provided elsewhere in this specification, to determine whether the contractual requirements have been met. No tolerance or allowance on the test results will be permitted, for instrument error or inaccuracy, the method of testing, or any other cause.
11.4.7
Rejection of plant If any item fails to comply with the requirements of the Specification in any respect whatsoever at any stage of manufacture, test or erection, KNOC may reject the item, or defective component thereof, whichever he considers necessary. After adjustment or modification as directed by KNOC, the Bidder shall submit the item for further inspection and/or test. In the event of a defect on any item being of such a nature that the requirements of the Specification cannot be fulfilled by adjustment or modification, such item shall be replaced by the Bidder, at his own expense, to the entire satisfaction of KNOC.
11.4.8
Liquidated damages If, after any such necessary repeat testing as may be permitted in the Contract or otherwise permitted by KNOC, the performance of any item exceeds the maximum or falls short of the minimum (as the case may be) required by the relevant Guarantee, then the Contract Price shall be reduced by amounts of 11-20 KHABAT TPP UNITS 1&2 - VOLUME I
money as specified in the section of the Specification dealing with performance guarantees and penalties.
11-21 KHABAT TPP UNITS 1&2 - VOLUME I
