1.Hydrostatic Test and Flushing(R2)

YANBU II POWER & WATER PROJECT PACKAGE: 3

Hydrostatic Test and Flushing Procedure for Piping

Document No. Revision Date of Issue

: : :

YANBU II POWER & WATER PROJECT Contract PO No.:


Doc No. : Rev No. :

Date of Issue: Page 2 of 19

METHOD STATEMENT FOR SPOOL FABRICATION OF STEEL PIPING

Document No.

:

Project Name

: YANBU II POWER & WATER PROJECT

Contract No.

:

Client

:

EPIC CONTRACTOR Rev

Date

Description

Prepared by

Reviewed by

Approved by

YANBU II POWER & WATER PROJECT Contract PO No.: Doc No. :

Hydrostatic Test and Flushing Date of Issue: Procedure for Piping Page 3 of 19

Rev No. :

Plant :

Document No. :

Rev.

Title :


REV.

DATE

Project :

Project Co. :

DESCRIPTION

BY

CHK

APP



Rev No. : EPC Contractor :

CONTENTS

SECTION

PAGE

1.0 SCOPE………………………………………………………………………………………3 2.0 REFERENCES………………………………………………………………………………3 3.0 EXCLUSIONS………………………………………………………………………………3 4.0 INSPECTION …………………………………………………………………….………...4 5.0 PRESSTRE TEST………………………………………………………………………..…4 5.1 General……………………………………………………………………………………4 5.2 Extent of Testing………………………………………………………………………….4 5.3 Test Preparation…………………………………………………………………………..5 5.4 Test Fluid and Test Pressure……………………………………………………………..6 5.5 Test Procedure………………………………………………………………………….. 7 5.6 Completion of Testing………………………………………………………………….. 7 5.7 Test Records……………………………………………………………………………. 8 6.0 FLUSHING…………………………………………………………….…………………... 9 Appendix 1 Cleanliness Requirements for Internal of Piping………………………………… 12 Attachment #1 Piping Line Final Certificate & Pressure Test Certificate (Fuel Gas Line)..…. 15 Attachment #2 Legend for Pressure Test ………………………………………………..……. 16 Attachment #3 Standard Detail for Pressure Test………………………………………..……. 17



Rev No. :

1.0 SCOPE This procedure covers the general requirements for flushing and pressure testing of piping systems to be used for YANBU II POWER & WATER PROJECT. This procedure shall be used in conjunction with the pressure test flow diagrams line list contained test blind locations, test legends, test pressure, test fluids, and other pertinent information. 2.0 References 2.1 Relevant Documents Unless otherwise specified, all reference documents, code and practices shall be taken in their latest edition -

Design Criteria for Piping

-

Piping Material Specification

-

Piping Construction Specification

-

ASME B31.1 Power Piping

3.0 EXCLUSIONS The following piping accessories and equipments shall be excluded or isolated from pressure testing of piping, but not limited to ; 1)

Rotating machinery, pumps, compressors, etc.

2)

Filter elements of strainers.

3)

Pressure relieving devices such as rupture discs and pressure relief valves.

4)

Pressure Vessels and Heat Exchangers.

5)

All instruments, including level controllers and gauge glasses.

6)

Pressure gauges.

7)

Expansion joints.

8)

Orifice plates.

9)

Flow nozzles.

10)

Pressure control valves.

11)

Deluge nozzles.

12)

Any other piping or equipments designated by Company (packaged units / Equipments shall be isolated or by-passed as required)

4.0 INSPECTION After completion of fabrication and erection, and prior to hydrostatic/pneumatic testing, the piping system shall be inspected to ensure that:



Rev No. :  Proper piping material has been used.  Piping has been erected as per drawings  All supports have been installed properly

5.0 PRESSURE TEST

5.1 General The test pressure shall, unless otherwise specified, be in accordance with ASME B3 1.1 Section 137 or this procedure. 5.2 Extent of Testing With the exclusion of instrumentation, piping systems assembled in the field shall be pressure tested. 1) To facilitate the testing of piping systems, vessels and other equipments shall be included in the system if the test pressure specified is equal to or less than that for the vessels and other equipments. 2) Pumps, compressors and other rotating equipment shall not be subjected to field pressure test. 3) Lines which are directly open to atmosphere such as vents, drains, safety valves discharge should tested, but all joints shall be visually inspected

not be

4) However, such lines if provided with block valve shall be pressure tested up to the first block valve. 5) Seats of all valves shall not be subjected to a pressure in excess of the maximum cold working pressure of the valve. Test pressure applied to valves shall not be greater than the manufacturer’s recommendation nor less than that required by the applicable code. Where allowable seat pressure is less than test pressure, test shall be made through an open valve. 6) Instruments in the system to be tested shall be excluded from the test by isolation or removals. 7) Restrictions which interfere with filling, venting and draining such as orifice plates etc. shall not be installed unless testing is completed. 8) Control valves shall not be included in the test system. Where bypasses are provided, test shall be performed through the bypass. 9) Pressure gauges which are parts of the finished system, but cannot withstand test pressure, shall not be installed until the system has been tested. Where piping systems to be tested are directly connected at the battery limits to piping for which the responsibility rests with other agencies, the piping to be tested shall be isolated from such piping by physical disconnection such as valve or blinds. 5.3 Preparation for testing 1) Prior to commencing Testing, QM shall verify with the Company's representative that all required nondestructive testing (NDT) such as radiography, ultrasonic, post-weld heat-treating, etc., has been completed. 2) Piping to be tested shall be barricaded as precautionary measure in the event of piping system rupture to eliminate hazards to personnel in the proximity of lines being tested. 3) Test shall be carried out with permanent gaskets installed unless specified otherwise. 4) All piping systems to be hydrostatically tested shall be vented at the high points and the systems purged of air before the test pressure is applied. 5) All piping field joints and welds shall be left UN insulated, exposed and primer coated for examination during the test. 6) Pressure gauges used in testing shall be installed as close as possible to the lowest point in the piping system



Rev No. : to be tested, to avoid overstressing of any of the lower portions of the system. For longer lines and vertical lines, two or more pressure gauges shall be installed at locations decided by the Engineer-in-Charge. 7) For lines containing check valves, any of the following alternatives shall be adopted for pressure testing. 8) Where possible, pressurize up-stream side of valve. If this impractical, the check valve shall be reversed or provide blind on valve flanges and test the upstream and downstream of the line separately and remove the blind after testing. At these flanges, temporary gaskets shall be provided during testing and shall be replaced by permanent gaskets subsequently. 9) Piping which is spring or counter-weight supported shall be temporarily supported, where the weight of the fluid would overload the support. Retaining pins for spring supports shall be removed only after testing is completed and test fluid is completely drained. 10) When testing any piping system, air of approximately 2 bars may be used as preliminary test to detect missing gaskets etc. as this avoids the necessity of draining the line to make repairs. 11) All piping shall be adequately supported before the pressure test. Spring or other variable type Supports shall be locked to prevent movement. 12) Piping containing check valves shall have the source of test pressure on the upstream side or removed clappers. 13) All in line valves including ball valves shall be pressure tested in the half open position. Other valves shall be tested in the fully open position. But, all control valves shall be removed prior to testing. Care must be taken not to damage valve soft seats. 14) Piping and equipment may be insulated before testing, but all circumferential welding joints shall be left UN insulated until suitable test acceptance by Company. 15) Hydro testing shall be performed via a manifold. The test pump shall be isolatable from the system with its own pressure gauge. Valves, hoses used in tests shall be suitable rated (use rating of max. test on line list throughout to avoid any confusion)

5.4 Test Fluid and Test Pressure 5.4.1. Test Fluid 1) In general all pressure tests shall be hydrostatic using plant water or raw water which is clean and free of silt. Maximum chlorine content in water for hydrostatic testing for stainless piping shall be 50ppm. 2) Air shall be used for testing if water would cause corrosion of the system or overloading of supports etc. Instrument air, service air, cooling air, Co2/N2/H2, fuel gas/oil, LP steam and GT bleed air piping shall be pneumatically tested. 3) For pneumatic testing, the test media shall be nonflammable or nontoxic. The use of air for testing shall be limited to a maximum pressure of 8.0 bars and in case only nitrogen gas for testing shall be limited to a maximum pressure of 100 bars.

5.4.2. Test Pressure The hydrostatic/pneumatic test pressure shall be as indicated in the line list or test package.

5.4.3. Hydrostatic Test Pressure 1) The hydrostatic test pressure at any point in the piping system shall not be less than 1.5 times the design pressure, but shall not exceed the maximum allowable test pressure of any no isolated components such as vessel, pumps, or valves, nor shall it exceed the limits imposed by Para. 102.3.3(B) of B31.1.



Rev No. : 2) The pressure shall be continuously maintained for a minimum time of 10 minutes and may then be reduced to the design pressure and held for such time as may be necessary to conduct the examination for leakage.

5.4.4. Pneumatic test pressure 1) The pneumatic test pressure shall not be less than 1.2 or more than 1.5 times the design pressure of the piping system. The test pressure shall not exceed the maximum allowable test pressure of any non-isolated components such as vessels, pumps, or valves, in the system. 2) For firefighting system, the piping shall be pneumatically tested in closed circuit for a period of 10 min. at 40 psi (276 kpa). At the end of 10 min. the pressure drop shall not exceed 20% of the test pressure (Para 7.7.2.2.12 of NFPA 2001- 2008 edition) 3) The pressure in the system shall gradually be increased to not more than one-half of the test pressure, after which the pressure shall be increased in steps of approximately one-tenth of the test pressure until the required test pressure has been reached. 4) The pressure shall be continuously maintained for a minimum time of 10 minutes and shall then be reduced to the design pressure and held for such time as may be necessary to conduct the examination for the leakage.

5.4.5. Test pressure Gauge 1) All gauges used for field testing shall have suitable range so that the test pressure of the various systems falls in 35% to 65% of gauge scale range. Gauge shall have accuracy of at least 1 % of full scale. 2) Prior to the start of any test or periodically during the field test program, all test gauges shall be calibrated using a standard dead weight gauge tester or other suitable testing apparatus and test certificate shall be available. 3) A minimum two pressure gauges are required for the test system. One pressure gauge shall be on the test pump and the other on the test system.

5.5 Test Procedure 5.5.1. Hydrostatic Test 1) All vents and other connections used as vents shall be left open while filling the line with test fluid for complete removal of air. In all lines for pressurizing and depressurizing the system, temporary isolating valves shall be provided if valve, vents, drains do not exist in the system. 2) Pressure shall be applied by means of a suitable test pump or other pressure source which shall be isolated from the system as soon as test pressure is reached and stabilized in the system. 3) The pump shall be attended constantly during the test by an authorized person. The pump shall be isolated from the system whenever the pump is to be left unattended. 4) Test pressure shall be maintained for a sufficient length of time to permit thorough inspection of all joints for leakage or signs of failure. Any joint found leaking during a pressure test shall be retested to the specified pressure after repair. The pressure shall be continuously maintained for a minimum time of 10 minutes. 5) The pump and the piping system to be tested are to be provided with separate pressure indicating test gauges. These gauges are to be checked by the standard test gauge before each pressure test. 6) Care shall be taken to avoid increase in the pressure due to temperature variation during the test, if pressure rise, some quantities should be drained to maintain the pressure level. . 7) Gradual increase in pressure required for GRP/GRE piping as per vendor recommendations. Sudden pressure surges or water hammer should be avoided. Test pressure will be 1.5 x Design pressure as shown in line list.



Rev No. : The test pressure will be held for minimum 10 minute. 8) For pressure tests greater than 2,900 psi (200 bar = 204 kg/cm2 ), the pressure build up shall be as follows 25%, 75% test pressure in stage allowing a period of 5 minutes at each stage in order to permit system to stabilize.

5.5.2 Pneumatic Test 1) When testing with air, pressure shall be supplied by means of a compressor with a receiver, after cooler and oil separator. 2) Piping to be tested by air shall have joints covered with a soap and water solution so that the joints can be examined for leaks. 3)

All other details shall be same as per hydro testing procedure (specified above).

5.6 Completion of Testing 1) After the hydrostatic test has been completed, pressure shall be released in the highest vent point in a manner and at a rate so as not to endanger personnel or damage equipment. 2) All vents and drains shall be opened before the system is to be drained and shall remain open till all draining is complete, so as to prevent formation of vacuum in the system. After draining, lines/systems shall be dried by air. 3) After testing is completed, the test blinds shall be removed and equipment/piping isolated during testing shall be connected using the specified gaskets, bolts and nuts. 4) Items that were removed from test shall be reinstalled. 5) Pressure test shall be considered complete after approved by the Owner. Defects, if any, noticed during testing, shall be rectified immediately.

5.7 Test Records Test records shall be prepared and submitted by the inspector for each piping system for the pressure test done in a defined format. 6.0 FLUSHING



Rev No. : 6.1 The flushing shall be carried out after pressure testing. But in case water flushing shall be carried out after pressure testing. Pipe work shall be free from dirt, grease or temporary protective coatings, e.g. tape, at all joints including welded attachments. 6.2 The flushing shall be proceeded to expedite the progress even though the document review (like NDE review) was not done. Any outstanding repairs will require re flushing, unless specifically approved otherwise. 6.3 All flushing activities must be witnessed by Companies Representative and Contractor QC inspector. The Cleanliness of flushed pipe work must be to the satisfaction of Companies Representative. 6.4 Preparation and Procedure 1) Generally the flushing medium shall be plant water, raw water, steam or compressed air and seawater for GRP/GRE lines. In cases where water flushing is not desirable in the piping system (e.g. instrument air etc.), flushing by compressed air shall be carried out. 2) For air flushing, the pipe line/system will be pressurized by compressed air to the maximum pressure of 50 psig or up to design pressure whichever is lower. The pressure shall then be released by quick opening of a valve, already in line or installed temporarily for this purpose. This procedure shall be repeated as required till the inside of the pipe is cleaned to the cleanliness levels of particular piping system as indicated in Appendix 1 of this document. Caution: small bore pipe work which is safety hazard shall require personnel barriers. 3) The cleaning fluid shall not flow through vessels, pumps and other rotating equipment which are already cleaned and preserved by respective vendor. The pipe line shall be disconnected and blanked off before flushing/blowing. 4) Pumps and other rotating equipment designed with tight clearances as well as some control valves and in-line instruments like orifice plates, Rota meters, and safety valves etc. which may interfere or be damaged by flushing (water, steam or compressed air) shall be removed, blocked off or isolated. 5) All in line valves such as Butterfly valve, Gate valve, Ball valve (equal or less than 4”), Globe valve and DBB valves shall be flushed in fully open position. But, other valves such as Control valves, Flange type Check valves shall be removed or bypassed. 6) All instrument impulse pipe work shall be disconnected prior to flushing and shall remain disconnected during pressure test. 7)

All check valves larger than 2.5” shall be removed for duration of flushing.

8) The screens/meshes shall be removed from all strainers before flushing. Screens/meshes shall be reinstalled after flushing but before testing. 9) The contractor shall carry out all the activities required before, during and after the flushing operation as per flushing requirements, such as removal of valves, special items, distance pieces, inline instruments and any other piping part before flushing. The flanges shall be disengaged and provided with temporary gaskets at the time of flushing. Refer to P&IDs and piping isometric drawings. 10) After flushing is completed, the valve, distance pieces, piping specials etc. shall be reinstalled by the contractor with permanent gaskets. However, flanges at equipment nozzles and other places where isolation is required during testing, only temporary gaskets shall be provided. A proper record by marking on the P&IDs and the isometric drawings shall be maintained. 11) specified

The cleanliness shall be verified visually or if required by other appropriate method

12)

In case the piping system cannot be taken into commissioning directly after Pressure Testing



Rev No. : such as feed water, main stream and fuel gas piping. The piping shall be dried prior to introducing nitrogen and preserved with nitrogen. 13)

All opening in cleaned system shall be sealed with cap, plug or blind plate.

14) The system shall be pressurized with nitrogen up to 0.3 kg./cm2 and maintained with the pressure between 0.2 kg/cm2 and 0.3 kg/cm2 by adding nitrogen. 15) Records shall be prepared by the inspector of the Contractor and submitted to the Owner’s representative to sign acceptance of cleanliness, if the Owner’s representatives want to review it.

6.5 Steam Blowing Follow the document of “Steam Blowing out Procedure”: will be informed later.

6.6 Air Blowing 1) This method should be used as a cleaning method for fuel gas, fuel oil, instrument/service air and N2/Co2/H2 gas lines and feed water line. Two main methods of air blowing shall be used depending on the diameter of the lines, the quantity of fluid to be used and the time needed to fill in the system at the desired pressure. 2) Practically, continuous air blowing may be used up to NPS 6” pipe, the quick decompression method for pipes over NPS 6”. 3) Air is continuously blown from a source (Air compressor of a large capacity) at a high velocity through the lines to carry away the foreign matters. Due to high velocity of the air, a light erosion of the walls generally can occur during the air blowing, which is beneficial with regards to cleaning. Blowing of galvanized steel pipe shall be mild so as not to affect the galvanized coating. 4) Quick decompression 5) A pipe network is pressurized by compressed air up to a maximum pressure of 50 psig or up to design pressure whichever is lower. The pressure shall then be released by quick opening of valve, already in line or installed temporarily for this purpose. The quick decompression causes a high velocity of air flow in the pipes, thus removing foreign matters and performing a light erosion on the walls which eliminates rust. 6) For some operations, oil free air/dried air might be needed.



Rev No. : Fluid Code

System Description

Flushing/Blowing Fluid

Chemical Cleaning

Cleanliness Class (See Note A,B,C,D)

FG

Fuel Gas

Air/N2

No

450 mg/m2

HS

High Pressure Steam

Steam

No or Yes

As per Steam Blowing Procedure

HR

Steam

No or Yes


Steam

No or Yes


Air or Steam

No

GS

Hot Re-heater Steam Cold Re-heater Steam Low Pressure Steam Sealing Steam

Air or Steam

No

LO

Lube Oil

Oil

No

FO

Fuel Oil

Water or Air

No

FW

Feed Water

Water

No

C

CN

Condensate

Water

No

C

SM

Sampling

Water or Air

No

C

CF

Chemical Feed

Water or Air

No

C

Water

No

C

CR LS

MW

Mark-up Water

Remarks Note C

CC

Closed Cooling Water

Water

No

C

DW

Water or Air

No

C

TW

De-mineralized Water Permeate Water

Water or Air

No

C

SA

Service Air

Air

No

250mg/m2

CA

Cooling & Sealing Air

Air

No

IA

Instrument Air

Air

No

250mg/m2

Note C

NG

N2 Gas

Air

No

250mg/m2

Note C

CS

Co2 Gas

Air

No

80mg/m2

Note C

HY

H2 Gas

Air

No

80mg/m2

Note C

250mg/m2

Note C Note C

YANBU II POWER & WATER PROJECT Contract PO No.:


Doc No. : Rev No. :

6.7 Water Flushing 1) Closed Cooling water piping systems shall be flushed with a circulation of water at velocities greater than those in services fluid but at a minimum velocity of 1.5 m/sec through the pipe. 2) Chloride content in water for flushing of stainless piping shall be 50 ppm maximum.

6.8 Cleanliness Criteria 1) The degree of cleanliness required of components and systems is in relationship with the function of the particular component or system after construction. Four classes of cleanliness are provided in this document. If no cleanliness class is specified, internal surfaces shall meet the requirements for class D cleanliness as a minimum. 2) Cleanliness class and criteria for specific system are indicated in Appendix 1 in this document.

Appendix 1- Cleanliness Requirements for Internal of Piping Fluid

System

Flushing/Blowing

Chemical

Code

Description

Fluid

Cleaning

Cleanliness Class (See

Remarks

Note A,B,C,D)

SW

Service Water

Water

No

D

PW

Potable Water

Water

No

C

WO

Oily Waste

N/A

No

Water

No

N/A

No

Water WW

Waste Water

WS

Sewage

FF

Fire Water

Water

No

RW

Raw Water

N/A

No

XF

Vent

N/A

No

ZZ

Drain

N/A

No

D

D

Note A. Cleanliness to be verified by visual inspection unless specific requirement is described. B. Vent and drain piping is excluded from the requirements of this specification, unless otherwise specified. C. Cleanliness verification for the fuel gas line and other lines require air blowing



Rev No. : should be as per recommendation. After internal surfaces have been cleaned and dried, dry smear samples shall be taken from representative surfaces of the piping and verified clean to the mg/m2 levels specified in the above table. This verification can be by the optical comparison method of Figure 6 or the reflectance meter method or equivalent method. D. Cleanliness class and criteria Class A A very high level of cleanliness there is no evidence of contamination of the surface, either under visual examination, with or without magnification, or with the aid of sensitive detection methods. Class A cleanliness is applied to special systems and/or components such as delicate instruments and other close tolerance or carefully controlled surfaces or assemblies. Such systems or components should receive their required level of cleanliness at the point of manufacture and cleanliness must be maintained at the construction site. Normally any required site cleanliness inspection and/or re-cleaning should only be performed by supplier’s representatives or under the supplier’s supervision. Class B A high level of cleanliness meets the following guidelines. If flushing is the only practical means for evaluating the cleanliness of internal surfaces, a 20 mesh (850micrometer, ASTM E- 11, Specification for Wire Cloth and Sieves for Testing Purposes) or finer filter, or the equivalent, shall be installed in the system or component flushed with water. The system or component shall be flushed at the required velocity until the screen shows no more than a slight speckling and no more than a slight rust staining. There shall be no particles larger than 0.8mm by 1.6mm long. In water flushed systems, there shall be no visual evidence of contamination such as oil or discoloration in the effluent flush water. Note : Class B cleanliness should be specified for carbon steel and low alloy steel surfaces only in special cases because of the difficulty in maintaining such surfaces in the condition after the flush. Class C An intermediate level of cleanliness in which the surfaces meet the requirements for Class B except as follows. -Thin, uniform rust films on carbon steel surfaces are acceptable. -Hard rust which forms in a crusty film and tends to break off in pieces or flakes and/or heavy rusting is not acceptable for carbon steel and must be removed. Class D A nominal level of cleanliness the following are acceptable. -Rust films on both corrosion resistant alloys and carbon steel and low-alloy steel surfaces. -Tightly adherent mill scale on non-machined carbon and low-alloy steel surfaces. - Paint or preservation coatings on carbon and low-alloy steel surfaces that will not peel or flake when subjected to cold water flushing. - Particles no larger than 1.6mm by 3.2mm on 14 mesh (1.4mm, ASTM E-1 1, Specification for Wire Cloth and Sieves for Testing Purposes) or finer filter, or equivalent.



Rev No. :

ATTACHMENT # 1: Piping Line Final Certificate & Pressure Test Certificate (Fuel Gas Line)

YANBU II POWER & WATER PROJECT Contract PO No.: Doc No. : Rev No. :




Rev No. :

ATTACHMENT # 2: LEGEND FOR PRESSURE TEST

YANBU II POWER & WATER PROJECT Contract PO No.: Doc No. : Rev No. :




Rev No. :

ATTACHMENT # 3: STANDARD DETAIL FOR PRESSURE TEST

1.Hydrostatic Test and Flushing(R2)

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