HAYWARD TYLER ENGINEERED PRODUCTS
BHARAT HEAVY ELECTRICALS LTD (BHEL)
Kahalgaon Power Station
SERIAL NUMBERS EP/03/10757A,B,C,D,E EP/03/10757A,B,C,D,E & F EP/04/10794A,B EP/04/10794A,B & C
3 X 500 MW BOILER CIRCULATING PUMPS
FOREWORD
This instruction manual provides comprehensive installation, operating and maintenance information of a Hayward Tyler Glandless, Wet Stator, Motor Pump Unit, referred to in the text as the circulator.
Each section contains an itemised Contents List. The major illustrations of the Pump and Motor are included at the rear of Section 7. Additional illustrations of particular features are incorporated in the text.
The General Contents list shows that the manual is divided into eight main sections. Paragraph references are consecutive throughout each section, and are preceded by the appropriate section number. For example example 5.1. designates:-
Note! Where a customer customer boiler layout drawing is shown, this is used in good faith. However, Hayward Tyler can accept no responsibility for any errors or consequences that may result. Hayward Tyler Manuals are for guidance only and we reserve the right to update, revise and modify this manual in accordance with our continuous research and development programme.
Section 5, Commissioning. 5.1. Pre-Start Check List. Hayward Tyler Engineered Products Ltd. 1 Kimpton Road Luton Bedfordshire ENGLAND LU1 3LD Telephone: Email: Fax:
Revised manuals will not automatically be issued, however, should they be required, Hayward Tyler may be contacted and arrangements can be made.
+44 (0) 1582 731144
[email protected] +44 (0) 1582 452198
i
GENERAL CONTENTS
BOILER CIRCULATING PUMP – INSTRUCTION AND MAINTENANCE MANUAL
SECTION 1
TECHNICAL DATA
SECTION 2
STORAGE
SECTION 3
DESCRIPTION
SECTION 4
INSTALLATION
SECTION 5
COMMISSIONING
SECTION 6
OPERATION
SECTION 7
MAINTENANCE
SECTION 8
STUD TENSIONING
ii
SECTION 1 TECHNICAL DATA
CONTENTS
PARAGRAPH
PAGE
1.1
GENERAL
1.1
1.2
CHARACTERISTICS
1.1
1.3
MOTOR CHARACTERISTICS
1.2
1.4
CLEARANCES AND SETTINGS
1.2
1.5
HEAT EXCHANGER
1.3
1.6
INSTRUMENTATION
1.3
1.7
TORQUE LOADINGS
1.3
1.8
WEIGHTS (APPROXIMATE)
1.3
ILLUSTRATIONS
FIGURE 1/1
MOTOR ASSEMBLY
1.4
FIGURE 1/2
WINDING RESISTANCE DIAGRAM
1.5
FIGURE 1/3
PUMP PERFORMANCE CURVE
1.6
FIGURE 1/4
MOTOR PERFORMANCE CURVE
1.7
1. 0
SECTION 1 TECHNICAL DATA
1.1
GENERAL
Unit Serial Nos:
EP/03/10757 A B C D E F & EP/04/10794 A B
Customer Order No:
0130645 & 0140593
Service:
Boiler Water Circulating Pump with Motor below Pump.
Number Supplied:
9
Electrical:
3300V - 3 Phase - 50Hz
1.2
CHARACTERISTICS
Type:
Single Suction - Double Discharge
Size:
(2 x 13) x 16 x 19H Volute
Design Pressure:
214 kg/cm2
Design Temperature:
370°C
Hydrostatic Test pressure:
321 kg/cm2
Suction Pressure:
197.4 kg/cm2
Specific Gravity at pump suction
0.542
N.P.S.H. required:
15 m (3% head drop)
Quantity Pumped:
3135 m3/hr
Differential Head:
32.37 m
Pump Efficiency:
83 % Cold
83 % Hot
kW Absorbed:
333.1 Cold
180.5 Hot
1.3
MOTOR CHARACTERISTICS
Type:
Wet Stator Squirrel Cage Induction
Output:
360 kW
Service Factor:
1.0
Winding Insulation:
XLP
Motor Case Design Pressure
214 kg/cm2
Motor Case Design Temperature
368oC
Speed:
1450 RPM. Hot Duty
Cold Test
Motor Efficiency:
89.5 %
89.5 %
kW Input:
201.7
372.2
Power Factor:
74.0
82.5
Overall Efficiency:
74.3 %
74.3 %
Full Load Current:
85 amps
Motor Starting Current:
410 amps
1. 1
SECTION 1 TECHNICAL DATA 1.4
CLEARANCES & SETTINGS
(mm)
Initial
Maximum
Impeller Wear Ring Clearance : ∅
1.46 – 1.58
2.03
Journal Bearing Clearance : ∅
0.20 - 0.38
0.55
Reverse Thrust Wear Ring Clearance :
0.42 - 0.52
0.76
∅
Rotor End Float:
0.50 - 0.80
Impeller Setting (Dimension ‘Z’):
572.5 – 571.5 mm
1.5
1.50
INSTRUMENTATION:
Temperature Switches:
Ashcroft Model T.461-T20-030-69C-XNH: 20-950C with 6096 mm capillary. 15amp. 125 to 250 Volt AC. Alarm Setting 60°C Trip Setting at 65°C
Thermometer:
Pressure Gauge:
Ashcroft Model 600A-03-C41-B01-A1-L07-BSXNG 0 0-120 C – CD1 Ashcroft Model 60-1379SSL-04L-XNH-XNG 0-250 Kg/cm2 – CD1.
Flowmeter:
Thermocouples:
KDG Mobrey Series 250 Rotameter Model 250-50-CX-M12-TO-S6-Z6 Relay Mains supply: 220V 50/60 Hz Contact Cut Off Capacity: Max 250V/4A/500VA Type ‘K’ Dual Element – Ungrounded
1.6
TORQUE LOADINGS:- Refer to Figure 1/1, Schedule of Torque Loadings
1.7
WEIGHTS (Approximate)
Pump Case
3425 kg
Motor Complete
6020 kg
Heat Exchanger
410 kg
1. 2
SECTION 1 TECHNICAL DATA
TOTAL
9855 kg
1. 3
SECTION 1 TECHNICAL DATA
Figure 1/1 Motor Assembly 1. 4
SECTION 1 TECHNICAL DATA
Figure 1/2 Winding Resistance Diagram
1. 5
SECTION 1 TECHNICAL DATA
Fi ure 1/3 Pum Perform Performanc ancee Curv Curvee
1. 6
SECTION 1 TECHNICAL DATA
Figure 1/4 Motor Performance Curve
1. 7
SECTION 2 STORAGE
CONTENTS
PARAGRAPH
PAGE
2.1
ENVIRONMENT ENVIRONMENT
2.2
2.2
STORAGE - GENERAL
2.2
2.3
INHIBITOR INHIBITOR
2.2
2.4
HEAT EXCHANGER EXCHANGER
2.2
2.5
EXTERIOR SURFACES
2.2
2.6
STANDARD STORAGE CHECKS FOR STORAGE UP TO 3 YEARS
2.3
2.7
STORAGE PERIODS GREATER THAN 3 YEARS
2.4
2.8
PREPARATION FOR STORAGE AFTER USE
2.4
2.9
INSPECTION RECORD CARDS
2.4
ILLUSTRATIONS
FIGURE 2/1
MOTOR STORAGE / TRANSIT DETAILS
2.1
FIGURE 2/2
PUMP CASE STORAGE DETAILS
2.2
FIGURE 2/3
INHIBITOR FILLING VALVE
2.3
FIGURE 2/4
ROTATING THE ROTOR ASSEMBLY
2.5
FIGURE 2/5
INSPECTION INSPECTION RECORD CARD
2.6
FIGURE 2/6
CHECK LIST
2.7
2.0
SECTION 2 STORAGE
Figure 2/1 Typical Motor Transit/Storage Details
2.1
SECTION 2 STORAGE
2) The motor apertures must be blanked off with flanges secured with studs, bolts and nuts (Fig. 2/1).
2.1 ENVIRONMENT The storage area must have a hard standing floor that will be capable of supporting the weight of the units.
3) The motor and transit assembly must be filled to the top of the transit canister with inhibitor of the appropriate concentration, through the filling connector located in the temporary transit flange, sealing off the motor heat exchanger bottom outlet.
2.2 STORAGE – GENERAL 2.2.1 Pump Case (Fig. 2/2) 1) The pump case internal cast areas and all machined faces must be cleaned and a suitable removable solvent rust preventative, with a minimum effective life of 6 months, applied. Recommended rust preventatives are, Jenolac J400 or Shell Ensis Fluid 264, or their equivalents.
2.3 INHIBITOR Inhibitor is to be produced from a pre-mixed concentration of mono-propylene glycol and distilled water in a 50/50 solution by volume. The mono-propylene glycol must contain corrosion inhibitors and meet BS6580 or equivalent. A tolerance of ±5% on the normal glycol/water mix may be applied.
2) All pump case openings must be closed with covers. These covers to be secured to the weld preparations with steel banding and the pump case main flange with the existing studs and nuts supplied on the pump flange.
The distilled water used must have a conductivity of less than 10 reciprocal megohms (microsiemens) per centimetre. Check the specific gravity of the inhibitor to ensure the correct concentration. The specific gravity of the mixture at 20°C is as follows:Mixture by%Volume
Specific Gravity
45% MPG /55% Water
1.036
50% MPG /50% Water
1.038
55% MPG /45% Water
1.040
MPG = Mono-propylene Glycol
2.4 HEAT EXCHANGER
Figure 2/2 Pump Case Storage Details
The heat exchanger should be stored as instructed by the manufacturers.
2.2.2 Motors (Fig. 2/1)
The heat exchanger interconnecting pipe work and the fill and drain assemblies must also be filled with the same inhibitor as the motor, blank flanges being used to seal both ends.
1) The motor and transit assembly must be stored in a vertical position standing on the motor cover end. NOTE: When the terminal box protrudes below the motor cover stand, rest the motor cover on balks of timber of sufficient height to keep the terminal box clear off the ground (Fig. 2/1)
2.5 EXTERIOR SURFACES All exterior surfaces of the motor must be maintained in a good painted condition. Scratched or damaged paintwork must be repainted.
2.2
SECTION 2 STORAGE CAUTION: To rotate the assembly in a clockwise direction may damage the impeller nut locking screw.
2.6 STANDARD STORAGE CHECKS FOR STORAGE UP TO 3 YEARS A visual examination and inspection of the motor and transit assembly must be made at least every three months as follows:-
b) If the shaft cannot be rotated or is very difficult to turn, the motor must be stripped down and inspected as outlined in Section 7.
NOTE: When stored by the contractor, or by an agency, a record card should be kept of the intervals between inspections and the results of the following inspection checks recorded.
8) Check the inhibitor level in the motor and transit assembly. The level of inhibitor must not fall below the level of the impeller. Top up if necessary.
2.6.1 MOTOR
9) Check the glycol/water concentration by measuring the specific gravity of the inhibitor. The inhibitor is considered acceptable if it conforms to the concentration and tolerance given in paragraph 2.3.
1) The motor is stored vertically resting on the motor cover - not horizontally. 2) The exterior paintwork is in good condition. Repaint where necessary. 3) All flanges and joints are tightly secured and no leakage of the inhibitor has taken place.
10) Replace the transit inspection cover when the inspection is satisfied. 2.6.1.2 Topping up/Draining Inhibitor (Fig 2/3)
4)
1) Remove the access cover plug.
a) All studs, bolts and nuts are present and in sound condition.
2) Attach a hose leading from a pumping device to the hose tube of the inhibitor filling valve.
b) The phosphate, or any other plating, applied to these items has not deteriorated. ambient
3) Unscrew the filling valve screw by two turns. This action opens the valve to allow the pumped liquid to enter the motor.
6) Check and record the insulation resistance of the stator windings as follows:
4) When the sufficient inhibitor has been pumped in, turn screw to close the valve.
5) Measure and record the temperature of the storage area.
a) Remove the terminal box cover.
5) Remove the hose from the inhibitor filling valve.
b) Check the insulation resistance at the terminal stems using a l000V megger. Record the result.
NOTE: If the motor is to be drained, allow the liquid to flow out of the valve hose tube. Ensure disposal of inhibitor is carried out in accordance with local regulations.
IMPORTANT: If any insulation resistance value falls below 200 megohms at 20°C this, and any previous readings, with dates, must be reported to Hayward Tyler for comment.
c) Fit the terminal box cover. 7) a) Remove the inspection cover from the top of the transit canister (Fig.2/1). Fit impeller wrench onto the impeller nut and rotate the rotating assembly seven complete revolutions in an anticlockwise direction when viewed from the pump-end.
Fi ure 2/3 Inhibitor Fillin Valve
2.3
SECTION 2 STORAGE
2.6.1.3 Pump Case and Transit Assemblies
2.8 PREPARATION FOR STORAGE AFTER USE.
Inspect the pump assembly and check the following: -
1) Remove the motor from the pump case and drain the motor as described in Section 7.
1) No extensive corrosion has occurred on the internal pump cast or machined areas. 2) The protective coating is satisfactory. Re-apply if necessary. 3) Visually damage.
examine
the
assembly
2) Disassemble the motor cover and clean out any loose material, sediment etc.
for
3) Disassemble the motor as described in Section 7.
4) Check that the pump case protective flanges are correctly fitted and secure.
4) Check all fittings and clearances and general condition (Section 1). Fit spare parts as necessary.
2.6.2 Stud Tensioning Equipment After use, the stud tensioning components must be thoroughly cleaned, examined for damage and a rust preventative lubricant applied to all surfaces.
5) Reassemble the motor as described in Section 7. 6) Using special wrench provided on the impeller nut, check that the shaft rotates freely, approximately seven revolutions in an anti-clockwise direction.
The components must be then wrapped in suitable waterproofed material and stored in a clean, dry area.
7) Check the insulation resistance of the winding. This should not be below 200 megohms.
2.7 STORAGE PERIODS GREATER THAN THREE YEARS
8) Fit the transit canister to the main flange and stand the motor upright on the motor cover.
Units that remain in store over three years require special consideration and Hayward Tyler Limited should be consulted for specialist advice.
9) Seal off all apertures with appropriate transit flanges and gaskets.
Motor assemblies that are stripped must be reassembled using new gaskets, the details recorded on the storage record card stating that it has been stripped and listing any relevant findings.
10) Fill the motor with a pre-mixed concentration of inhibitor, in accordance with paragraph 3, through the filling connection in the transit flange, sealing the motor heat exchanger bottom outlet.
CAUTION: Precautions must be taken prior to use that the unit is pressure tight.
11) Fit the transit canister inspection cover. 12) Re-check the insulation resistance of the motor windings. 13) Check that the storage conforms to Para 2.2.
2.9 INSPECTION RECORD CARD (Fig. 2/5 and Fig 2/6)
A typical inspection record card and check list is given on the following pages.
2.4
SECTION 2 STORAGE
Fi ure 2/4 Rotati Rotatin n the Rotor Rotor Assem Assembl bl
2.5
SECTION 2 STORAGE
Fi ure ure 2/5 2/5 Ins Ins ectio ection n Reco Record rd Car Card d
2.6
SECTION 2 STORAGE
Fi ure 2/6 Check Check List List
2.7
SECTION 3 DESCRIPTION
CONTENTS
PARAGRAPH
PAGE
3.1
GENERAL
3.1
3.2
PUMP
3.1
3.3
MOTOR
3.1
3.4
TERMINAL BOX
3.5
3.5
HEAT EXCHANGER
3.5
3.6
ALARM SYSTEMS
3.5
ILLUSTRATIONS
FIGURE 3/1
AUXILARY COOLING CIRCUIT
3.2
FIGURE 3/2
TERMINAL GLAND
3.4
3.0
SECTION 3 DESCRIPTION
3.1 GENERAL
3.2 PUMP
The Hayward Tyler Glandless Motor Circulator Pump is designed for recirculating boiler water through the boiler water systems of fossil fuel or liquid cooled nuclear reactor power stations and similar applications.
The pump comprises a single suction and double discharge branch casing, welded into the boiler system pipe work at the suction and discharge branches with the suction branch uppermost.
The circulators consist of a single stage centrifugal pump and a wet stator induction motor, which are mounted within a common pressure vessel. The vessel consists of three main parts, a pump casing, motor housing and motor cover.
Within the pump cavity rotates a key driven, mixed flow type impeller, mounted on the end of the extended motor shaft. 'Renewable’ wear rings are fitted to both the impeller and pump case. The impeller wear ring is the harder component to prevent galling
The motor is suspended beneath the pump casing and is filled with cold boiler water at full system pressure. No seal exists between the pump and motor, but provision is made to thermally isolate the pump from the motor in the following respect: -
3.3 MOTOR The motor is a squirrel cage, wet stator, induction motor, the stator wound with a special water tight insulated cable. The phase joints and lead connections are also moulded in an insulated material. The motor is joined to the pump casing by a pressure tight flange joint and a motor cover completes the pressure tight shell.
1) Thermal Conduction. Because the pump temperature is so high, usually above 340°C and the motor temperature is limited to about 55°C, a simple restriction, in the form of a 'neck', is provided to minimise heat conduction.
The motor shell contains all the moving parts, except for the impeller. Below the impeller is situated an integral heat baffle which reduces the heat flow, a combination of convection and conduction, down the unit. A baffle wear ringcum-sleeve above the baffle forms a labyrinth with the underside of the impeller to limit sediment penetration into the motor. Should foreign matter manage to pass the labyrinth device into the motor enclosure, a filter located at the base of the cover end bearing housing strains it out.
2) Hot Water Diffusion. To minimise diffusion of boiler water, a narrow annulus surrounds the rotor shaft, between the hot and cold regions. A baffle ring restricts solids entering the annulus. 3) Motor Cooling. The motor cavity is maintained at a low temperature by a heat exchanger in a closed loop water circulation system, thus extracting the heat conducted from the pump.
The motor design is such that for ease of maintenance, the stator shell, complete with the stator pack, the rotor shaft, the journal bearing housings and the thrust assembly, can be withdrawn from the motor case in sequence. Lifting lugs are supplied to secure hoists when raising and lowering the motor.
In addition, this water circulates through the stator and bearings, extracting the heat generated in the windings and providing bearing lubrication. An internal filter is incorporated in the circulating system. 4) In emergency conditions, if low pressure coolant to the heat exchanger fails, or is inadequate to cope with heat flow from the pump case, a cold purge can be applied to the bottom of the motor to limit the temperature rise. NOTE: A high pressure cold purge is to be used only as an emergency. (para 6.3.8)
3.1
SECTION 3 DESCRIPTION
Figure 3/1 Auxiliary Cooling Circuit
3.2
SECTION 3 DESCRIPTION 3.3.1 Auxiliary Cooling Circuit (Fig. 3/1)
The motor is provided with its own auxiliary closed circuit, which besides cooling the motor lubricates the bearings. The water is continuously circulated through the bearings, motor windings and an external heat exchanger (cooler), by an auxiliary impeller at the thrust bearing end of the motor shaft.
3.3.3 Internal Filter
A stainless steel woven wire strainer, fitted at the base of the reverse thrust seat, filters the liquid in the motor before it is circulated through the bearings after passing through the heat exchanger (cooler). The filter should be cleaned at normal maintenance periods, removing any accumulation of foreign matter in the motor cover.
When the motor is stationary, thermosyphon circulation takes place to remove conducted heat from the pump end of the motor.
3.3.4 Main Flange Joints
3.3.2 Bearings
The pressure joints at the pump and motor cover flanges employ spiral edge wound gaskets, specially designed for very high pressure and temperature. The main pump/motor flange gasket is housed in stainless steel overlay, recessed into the joint face.
The motor rotor shaft is supported by water lubricated tilting pad type radial and thrust bearings mounted on the stator shell, thus making the motor internals into a separate construction independent of the motor pressure vessel. 3.3.2.1 Journal Bearings
The studs and nuts securing the flanges are made from special high tensile steel and, because torque tightening these nuts is inadequate, the studs are hydraulically stretched and the nuts tightened down by hand. When the hydraulic tension in the stud is released, the load is transferred to the nut giving the required tightness.
The journal bearings of the circulator are the water lubricated Michell type located at the ends of the motor shaft, i.e. pump-end and cover-end. Each bearing comprises a hardened steel sleeve on the shaft running in six radially located tilting pads whose bearing surfaces are lined with a composite material. The bearing surfaces must never be allowed to operate in a dry condition.
Stud tensioning equipment is supplied with each circulator order.
3.3.2.2 Thrust Bearing
3.3.5 Terminal Gland
A main thrust bearing is situated below the cover-end journal bearing and takes the full hydraulic thrust of the pump. This bearing, also of the Michell water lubricated type, is formed by a steel thrust disc, with a composite bearing surface, on the botto m of the rotor shaft running on stationary hardened steel tilting pads.
The electrical supply to the motor is taken through special high pressure single lead cable terminal glands of the high temperature, safety type. The seal is effected by a terminal gland moulding, together with o-rings located between an insulating sleeve and an inner casing, and between the inner casing and the motor case. The addition of a cone-shaped collar within the terminal moulding, plus the design of the inner casing, prevents any possibility of a gland blowout at high temperatures. However, if the motor is subjected to sustained overheating, a slight leakage may occur into the terminal box.
The thrust disc is also designed to operate as an auxiliary impeller to circulate the internal water content of the motor. 3.3.2.3 Reverse Thrust Bearing
The weight of the rotating assembly, as well as the down thrust imposed at start-up and shut-down, are taken by a reverse thrust bearing located on a reverse thrust housing which forms the bottom of the cover housing cylinder. The reverse thrust housing also includes a composites reverse thrust wear ring and is the mounting for the internal filter.
3.3
SECTION 3 DESCRIPTION
Fi ure 3/2 Terminal Gland 3.4
SECTION 3 DESCRIPTION
3.4 TERMINAL BOX
3.6.2 Temperature Switches
Robust fabricated steel terminal boxes are provided on the side of the motor casing for connecting the power supply to the motor.
Two temperature switches, remotely mounted, are provided for actuating the alarm. When a pre-set temperature is reached, the alarm circuit is energised via one of the switches. Should the motor temperature continue to rise, the second switch is activated to de-energise the motor.
Each phase supply cable for the motor enters a box at its base and should be sealed by a cable gland. Each phase notation is identified by a colour coding, Red, Yellow or Blue.
3.6.3 Thermocouples
Bursting discs are fitted to the wall of the terminal boxes to relieve excessive pressure build up within the box should a flash over occur at the terminals.
A thermocouple is provided for measuring motor cavity temperature. Two thermocouples are also supplied with weld on pads for measuring the skin temperature of the pump case and suction manifold. These are to be installed on site by the user.
Desiccators are fitted to absorb atmospheric moisture that may decrease the electrical resistance to ground. Each assembly is completely enclosed by a bolted on cover.
3.6.4 Instrument Pockets
Temperature thermocouple required.
3.5 HEAT EXCHANGER A heat exchanger (cooler) must be fitted to dissipate the heat generated by the motor and the heat transferred from the pump casing.
3.6.5 Differential manifold
switch, thermometer and pockets are provided where Pressure
Transmitter
with
These are to be connected to the process connections in the pump case by the user. (Customer supply)
High pressure outlet and inlet raised facings are situated at the bottom and top of the motor case respectively for connection to high pressure heat exchanger / motor case stub pipes.
3.6.6 Pressure Gauge
A pressure gauge is remotely mounted to the motor case.
Interconnecting pipework must be short and direct with the heat exchanger mounted as high as possible to promote good thermosyphon circulation when the unit is on hot standby.
3.6.7 Flow Meter
A flow meter is supplied to be fitted in the low pressure cooling water return line by the user.
3.6 ALARM SYSTEMS
3.6.8 Ground Detection Relays
3.6.1 Thermometer
The motor windings should be protected by ground detection relays, sufficiently sensitive to detect the development of a pinhole or minor crack in the stator winding insulation.
The thermometer instrument is mounted adjacent to the motor, and gives visual indication of the motor temperature.
3.5
SECTION 4 INSTALLATION
CONTENTS
PARAGRAPH
PAGE
4.1
GENERAL
4.2
4.2
PUMP CASE INSTALLATION
4.2
4.3
PREPARATION FOR MOTOR INSTALLATION
4.2
4.4
MOTOR INSTALLATION
4.4
4.5
FITTING THE HEAT EXCHANGER
4.5
4.6
FILLING THE CIRCULATOR WITH BOILER COLD
4.6
4.7
HYDROTESTING BOILER WITH CIRCULATOR INSTALLED
4.6
4.8
ELECTRICAL CONNECTIONS
4.8
4.9
MOTOR PROTECTION
4.9
ILLUSTRATIONS
FIGURE 4/1
PUMP CASE INSTALLATION
4.1
FIGURE 4/2
MOTOR INSTALLATION
4.3
FIGURE 4/3
TERMINAL BOX
4.7
FIGURE 4/4
BURSTING DISC ASSEMBLY
4.8
FIGURE 4/5
EARTH LEAKAGE PROTECTION CIRCUIT DIAGRAM
4.10
4.0
SECTION 4 INSTALLATION
Fi ure 4/1 Pum Case Installation
4.1
SECTION 4 INSTALLATION 3) The cables, leading to the motor, should be flexible and looped immediately prior to entering the terminal boxes. The looping should be sufficient to accommodate unit movement caused by expansion and contraction of the boiler pipe work.
4.1 GENERAL WARNING The Hayward Tyler boiler circulating pump is a precision piece of heavy machinery. It should only be installed under the supervision of a qualified professional engineer who should ensure that the staff directly concerned are adequately trained and have read and understood this manual.
4.2 PUMP CASE INSTALLATION (FIG 4/1) 1) Remove the pump case flange and branch covers and clean the pump branches.
When installing the circulators the following conditions MUST be observed.
2) Attach shackles and slings to the casing eyebolts. A plate on the pump case indicates the front of the pump.
1) The system pipe work should be adequately supported to accept the weight of the circulator.
3) Raise the case to meet the system pipe work, with the suction branch uppermost.
2) When mounted, the pump should accommodate movement in the pipe work due to thermal expansion without imposing excessive loads on the casing and branches.
4) Ensure that the main motor/case flange is horizontal to within 1°. Tack weld to the system pipe work and re-check the horizontal limits.
3) Sufficient clearance should be allowed beneath the motor to permit lowering of the motor from the pump case for maintenance. (See Section 7 Fig. 7/35.). If removable floors or girders etc. are fitted after the motor is installed, ensure that the terminal boxes or low pressure cooling water supply lines will not foul them when the boiler is on load and the circulator moves downwards due to thermal expansion.
5) Complete the weld to the procedure approved by the boiler manufacturer and test radiographically for flaws. 6) On completion of a satisfactory radiographic test, fit any pressure differential transmitters using the stub pipes on the pump case branches. 7) Fit the blanking off plate until the motor is installed.
NOTE: Two long lift hoists should be used to raise the pump or motor, each hoist being capable of taking the full weight of the pump or motor
4.3 PREPARATION INSTALLATION
FOR
MOTOR
CAUTION: The motor should be stored, topped-up with inhibitor for as long as possible. If it is necessary to install the motor before boiler water is available, install in the inhibited condition to provide additional protection for the motor internal components. However, the inhibitor must then be drained immediately before mounting the heat exchanger.
4) The pump should be positioned so that the N.P.S.H. available exceeds the N.P.S.H. specified in the Technical Data - Section 1). NOTE: When operating at temperature, sub cooling of the inlet water is normally present and this gives a considerable increase in the N.P.S.H. available. The worst condition is normally operating cold.
We do not recommend motor installation on a Hot Boiler.
4.1.2 Installation Notes
1) Hose down internally, the pump case, the valves and adjacent-piping, to ensure the removal of all loose debris.
The following conditions must be observed when installing the circulator: 1) Ensure that the main system is free from solids before mounting the circulators.
2) Fully close the pump suction and discharge valves.
2) Permanent insulation should be applied only to the pump case. No insulating material must be applied to the motor case or to the main flange studs and nuts, as this will cause the motor to overheat. 4.2
SECTION 4 INSTALLATION
Fi ure 4/2 Motor Installation
4.3
SECTION 4 INSTALLATION 10) Ensure that the motor is in correct orientation with the pump case. See Section 7, Fig 7/35.
4.4 MOTOR INSTALLATION (FIG. 4/2) 1) Using a 1000V megger, check that the insulation resistance to ground of the motor leads is above 200 megohms when measured at the terminal stems with the unit full of water below approximately 20°C, if possible, or at normal ambient temperature.
WARNING The Hayward Tyler boiler circulating pump is a precision piece of heavy machinery. It should only be installed under the supervision of a qualified professional engineer who should ensure that the staff directly concerned are adequately trained and have read and understood this manual.
2) Stand the motor in a vertical position, on the motor cover stand, and in the correct orientation to the pump. 3) Remove the pump case main flange nuts and cover and ensure there is no debris in the pump pipe work system that could enter the pump case.
11) Attach shackles and slings to the motor casing lifting lugs and lift into position, taking care to avoid damage to the terminal box.
4) Clean and inspect the pump case flange, remove any burrs.
12) Fit the motor to the pump case as follows:-
5)
a) Using the chain type hoists, lift the motor until the impeller is about to enter the pump case.
a) Remove the plug or inspection cover at the top of the transit canister.
b) Measure the distance between the pump case and the motor flanges at four 90° degree points on the flange periphery. If necessary, adjust the lay of the motor by the chain hoists to make the distances approximately equal.
b) Loosen the inhibitor filling valve situated in the motor fill and drain transit flange, (Section 2 Fig. 2.1), of approximately 40-45 litres of inhibitor. Close the inhibitor filling valve. 6) Remove the transit canister from the motor case.
c) Bring the gap between the flanges equal all round. This is best achieved by using a spring-loaded 'inside' calliper, set to the gap directly in line with one of the chain hoists. The set calliper is then moved to the opposite side of the flange and the gap adjusted, using the chain hoist. Check the gaps at right angles to the first two and adjust the lay of the motor to make the gaps equal.
7) a) If the motor is to be operated immediately upon installation, completely drain then proceed as (8) b) If motor operation is not imminent, install the motor in the inhibited condition, proceed as 9), leaving 8) to be performed when fitting the heat exchanger.
d) Check that the studs are centred in the motor flange holes. Adjust the motor “lay” as required.
8) a) Connect a clean cold water supply to the motor cover fill and drain connection, and flush the motor until inhibitor-free water flows from the top of the motor.
e) With the chain hoists working in unison, slowly raise the motor. CAUTION. If any increase in effort is required on the chain hoists to raise the motor stop raising it immediately as the impeller may be fouling the pump case wear ring. In which instance, fractionally lower the motor, check the gap and raise the motor again.
b) Check that the shaft freely rotates, if not, strip the motor as described in Section 7 to establish the reason and correct the fault. 9) Clean the overlay that provides the seat for the gasket in the main flange of the motor. Inspect for burrs and surface discontinuity, dress if necessary with a fine grade stone. Fit a new gasket. NEVER apply any compound to the gasket and ensure that it is dry.
4.4
SECTION 4 INSTALLATION c) If, after fitting of the heat exchanger, running the motor is reasonably imminent, and sub-freezing temperatures are not envisaged, the motor and heat exchanger must be filled with treated boiler water or condensate within 3 hours of fitting.
f) Check the gaps every 10 mm, or less, during the last 100 mm of the motor raising sequence to ensure that the motor does not 'cock' or rotate as it is raised. Adjust the gap as necessary. g) Continue raising the motor until an increase in the effort required on the hoists indicates that the gasket is in contact with the pump case face. At this stage, the gap between the flange faces should be approximately 2.5mm and should be equal all round the flange.
4.5 FITTING THE HEAT EXCHANGER (CUSTOMER SUPPLY) 1) Remove the blank flanges from the motor high pressure outlet to cooler and fill and drain connection.
CAUTION: If the gap is unequal, the gasket may have come out of its recess. If the gap is unequal, lower the motor sufficiently to check the condition of the gasket. If the gasket is damaged renew. Never use any substance on the gasket to make it adhere to its recess.
2) Ensure that the motor, the heat exchanger and the high pressure pipe work and high pressure purge lines, have been flushed free from all obstructions and foreign matter. 3) Flush out the secondary cooling water system until clear water is discharged. 4) Mount the heat exchanger onto the motor case brackets and proceed.
h) Coat the stud threads with high temperature anti-seize compound or silicon grease and install the nuts by hand.
a) Bring the heat exchanger parallel to the motor supporting the weight with the lifting tackle.
NOTE: Do not coat the exposed extended diameter threads of the studs as these threads are for the tensioner application.
b) Clamp the heat exchanger to the motor by tightening up the securing bolts, nuts and washers. c) Ensure the motor / heat exchanger interconnecting pipe work assembly is correct for the circulator.
i) Tighten the nuts, using the hydraulic stud tensioner in accordance with the instructions in Section 8. Remove the lifting tackle and removable lifting lugs.
d) Offer up the interconnecting pipe work to the heat exchanger and motor flanges and complete all pipe welds and NDE in accordance with site approved procedures.
j) Thoroughly flush out the fill and drain system piping, to the motor cover and when satisfied that the piping is clean, connect to the motor cover.
5) Install gauges and recorders for temperature and pressure. Connect the low pressure cooling systems to the heat exchanger.
k) Install the heat exchanger: see Para. 4.5 l) Install the appropriate thermocouples, the thermometer, pressure guage and temperature alarm switches.
6) Fit temporary strainers to the low pressure cooling systems, and then check that circulation meets the heat exchanger specification.
m) Connect the power supply cables to the motor terminals, See 4.8.
7) Close the shut off valve in the high pressure fill and purge line and blow down piping.
n) Install the vibration pick up probes if permanent vibration monitoring is required.
The motor and heat exchanger circuit must now be refilled with inhibitor (See 4.4, Para. 13 (a) or (b) or with treated boiler water or condensate.
13) a) If, after fitting the heat exchanger, running is not reasonably imminent, the motor and heat exchanger circuit must be refilled immediately with inhibitor. b) If, after fitting the heat exchanger, subfreezing temperatures are envisaged the motor and heat exchanger circuit must be refilled immediately with inhibitor.
4.5
SECTION 4 INSTALLATION 5) After connecting the supply, open the heat exchanger vent on the high pressure side, fill the motor from the bottom and vent air from the top, until clean air free water is discharged from the vents.
4.6 FILLING THE CIRCULATOR WITH BOILER COLD Filling the circulator correctly is a prerequisite to ensure satisfactory operation. If air is present in the motor it could affect bearing lubrication and precipitate bearing failure.
6) Close the vent on the high pressure side of the heat exchanger. 7) Continue to fill the motor and vent any air via the vent connections in the boiler system pipe work.
If air pockets are present in the stator this would affect dissipation of heat generated in the windings, creating hot spots and consequent degrading of the insulating material, and ultimately cause winding failure.
8) Isolate the now filled circulator. 9) Ensure that the terminal box is dry and with the unit full of water below 20ºC or at normal ambient temperature, using a 1,000 Volt Megger, check winding resistance to ground at the terminals. The resistance should exceed 200 megohms.
Due to the complexity of the passages in the motor through which water must flow to displace all air, it is necessary to fill the motor very slowly. If air pockets are present in the stator this would affect dissipation of heat generated in the windings, creating hot spots and consequent degrading of the insulating material, and ultimately cause winding failure.
IF NOT, CALL HAYWARD TYLER. DO NOT ATTEMPT TO RUN THE MOTOR.
The maximum filling rate is 2 litres /min. The motor must NOT be filled via the pump casing, but only through the filling connector located at the motor cover.
4.7 HYDROTESTING BOILER CIRCULATOR INSTALLED
WITH
Treated Water or Condensate Available: -
1) Isolate the circulator from the boiler by closing appropriate discharge valves.
Should the customer wish to hydrotest the circulator, the hydrostatic test pressure must not exceed the maximum specified in Section 1.
2) Supply the low pressure side of the heat exchanger as follows: -
Treated Water Not Available: -
a) Open the supply valves in the low pressure cooling water system.
If the boiler is to be hydrotested at an early state of construction, the pump casing can be pressure tested without the motor once the blank off plate is installed – refer to para.4.2.
b) Flush out the piping for the supply of low pressure treated boiler water, or condensate, for filling the motor, until clean air free water is discharged.
4.7.1 Post Hydrostatic Test Procedure
NOTE: The flushing must always be carried out before introducing any water through the lines to the motor and heat exchanger.
1) Boiler circulators are not to be drained, but left filled to a level above the suction downcomer.
3) If the low pressure supply contains an orifice, check that it is clean and that its flow rate is correct.
2) Freezing can be avoided by filling with glycol in the concentration detailed in Section 2.
4) Adjust the flow rate to approximately 2 litres/min.
4.6
SECTION 4 INSTALLATION
Fi ure 4/3 Terminal Box
4.7
SECTION 4 INSTALLATION where it should be maintained at a temperature of 110oC until the colour reverts to blue. The re-activating time is between 1 and 2 hours.
4.8 ELECTRICAL CONNECTIONS 4.8.1 Power Supply to Motor
Refer to the terminal box arrangement shown in Fig. 4/3.
c) Screw the desiccators into the terminal box covers taking precautions not to damage the desiccators.
WARNING: Disconnect the power supply and the starter before commencing any work.
7) Fit and secure the terminal box covers using the nuts and washers previously removed.
CAUTION: Ensure that the cable length will accommodate expansion and removal of the circulator. Ensure that the voltage connected to the circulator is the correct operating voltage as stamped on the motor nameplate situated on the bottom of the motor case.
1) Remove the nuts and washers, and then remove the terminal box cover using lifting gear, if necessary. 2) Feed the cable through the conduit entry gland and connect to the terminals in the phase rotation RED, YELLOW, BLUE (‘U’, ‘V’ or ‘W’). When so connected the unit will operate in the designed direction, i.e. clockwise when viewed from above. All connecting cables and links are marked with appropriate phase colours. 3) Earth the circulator adequately. Earthing studs are provided on the motor casing adjacent to the terminal box. 4) Ensure that all electrical connections particularly at the terminal box entry gland are secure. 5) Fit the bursting discs to the terminal box as follows: -
Fi ure 4/4 Burstin Disc Assembl
NOTE: The bursting discs are supplied as loose items and are packed separately to prevent damage in transit. They are fitted to the terminal box on the installation of the motor.
4.8.2 Recommended Instrumentation
It is recommended that the following be provided: -
a) Dismantle the bursting disc assembly and discard the cardboard sheet fitted in lieu of the disc.
1) Pump suction gauges.
b) Reassemble the bursting disc assembly with the bursting disc in place, as depicted in Fig. 4/4.
and
discharge
pressure
2) Continuous record of motor voltage. 3) Continuous record of motor current. 4) Ground leakage relay to warn of very low winding resistance in order to prevent winding insulation failure.
6) Fit the desiccators, also supplied as loose equipment, as follows:a) Check that the desiccator crystals are coloured blue.
5) Indication and record of downcomer temperature and pump case temperature. This is required to avoid thermal shocks when starting a pump on a hot boiler.
b) If pink, reactivate by placing the desiccator in a well ventilated oven
4.8
SECTION 4 INSTALLATION 4.8.3 Alarm Circuits (Fig.4/5) 4.9.3 Starting Period Protection
WARNING: Lethal voltage is present in the alarm system when the motor is inoperative. To make the circulator safe - open the isolator.
Suitable alarm and trip devices should be fitted to protect the motor and arranged to provide: -
If the motor fails to start, trip out after a period of approximately 5 seconds. The starting current is based on a locked rotor test with an allowance made for saturation of the magnetic circuit.
1) An alarm - as an indication of motor overheat conditions.
Motor Starting Current: See Technical Data, Section 1.
2) Motor trip (shut down) - if the temperature rise continues above the alarm setting.
4.9.4 Earth Leakage Protection (Fig. 4/5)
Ground detection relays are recommended, sufficiently sensitive to sound an alarm if a pinhole or minor crack should develop in the stator winding. This protection is arranged in either of the ways shown in Scheme A, Scheme B or Scheme C.
The normally advised settings for the protection devices are: 57 C for alarm and 60 C for trip. In practice, the alarm setting should be reduced to 5 C above normal motor operating temperature. °
°
°
If the neutral point of the supply transformer is grounded, a current transformer (CT) is inserted into the ground lead, and a relay connected across the current transformer secondary, see Scheme A.
4.9 MOTOR PROTECTION The following protective provided for the motor: -
devices
must
be
4.9.1 Continuous Overload Protection
Experience indicates that in the event of a fine crack in the stator winding, the resistance to ground drops to between 20,000 and 30,000 ohms. The relay should not trip the motors but initiate an alarm.
The overload trip setting should be 10% above the maximum current requirements which could occur with the pump running on cold water at some other point than the specified duty, assuming nominal specified supply voltage. If voltage variation can occur, then the trip setting should be increased to 15% above maximum current value.
If the neutral point of the supply transformer is not grounded, three potential transformers (PT) are connected to the motor leads, with the secondaries connected in an open delta, closed by the relay winding, see Scheme B. The relay should not trip the motors but initiate an alarm.
NOTE Overload relays are now typically calibrated in motor full load current (FLC) where the relay trips with a current 10% above the FLC setting point. Hence the overload relay of this type should have a setting point of the cold duty current.
Scheme C shows a core balance earth leakage relay system where a core balance current transformer encloses supply lines L1, L2 & L3 supplying the motor.
Maximum current at nominal voltage:
NOTE It is important that no earth conductor is allowed to be enclosed by the current transformer. The earth leakage sensitivity and trip time can generally be selected to prevent nuisance tripping. Typical setting points are 300 mA and 1 second. This may require adjustment depending on supply conditions.
See Technical Data, Section 1. 4.9.2 Instantaneous Trip Setting
To allow for transients during the first cycles of the starting period, the instantaneous trip should be set at 12 times the motor full load current. Full Load current: See Technical Data, Section 1.
4.9
SECTION 4 INSTALLATION
Figure 4/5 Earth Leakage Protection Circuit Diagram
4.10
SECTION 5 COMMISSIONING
CONTENTS
PARAGRAP H
PAGE
5.1
PRE-START CHECK LIST
5.1
5.2
INITIAL STARTING-COLD BOILER CONDITION
5.1
5.3
STOPPING
5.3
5. 0
SECTION 5 COMMISSIONING When a boiler is started from cold, a minimum of two circulators must be operated. It is normal practice to simultaneously warm the standby circulators to permit immediate staring when required.
5.1 PRE-START CHECK The following pre-start checks must be satisfied before starting the motor. 1) Ensure that the circulator is completely vented.
CAUTION: 1. Motors must not be energised if the motor cavity temperature is below 2°C.
2) Ensure that the low pressure cooling water valves are open and the cooling water flow rate agrees with that specified in the heat exchanger manufacturer's specification. All other valves must be closed. NOTE: If the circulator is to be started on hot standby, the pump delivery by-pass valves must be open. Refer to the hot standby procedure in Section 6.
3.
The motor may be damaged if motor temperature exceeds 65°C.
2) Ensure that a flow of approximately 2 litres/min., is entering into the motor through the low pressure fill line.
4) Using a 1000V megger, check that the insulation resistance to ground of the motor leads conforms to the Winding Resistance curve shown in Section 1, Fig. 1/2 when measured at the terminal stems with the unit full of water below approximately 20°C, if possible, or at normal local ambient temperature. voltage
There should be at least ten-minute intervals between two repetitive starts. This must never be exceeded; otherwise the motor winding temperature will rise and could damage the winding insulation.
1) Ensure that the motor has been vented as detailed in Section 4, Para. 4.7.
3) Ensure that the high pressure cold water purge at 20°C maximum temperature is connected but isolated.
5) Check that the correct connected to the circulator.
2.
3) Ensure that the pre-start checklist, as described in Para. 5.1, has been satisfied. 4) a) Release any air trapped below the discharge valves by opening valves. b) When air-free water is discharged to atmosphere, close valves.
is 5)
6) Check that the electrical supply is available at the point of control selected and that the starting equipment is functioning correctly.
a) Vent the pump by opening vent valves. b) When air-free water is discharged from vent valve to atmosphere, close valves.
7) Test the operation of all instrumentation and alarms.
6) Make sure that the boiler is full and open the discharge valves.
8) Ensure that sufficient N.P.S.H. is available for the pump to run without cavitation.
NOTE: The by-pass valve should never be fully closed. It is normally throttled to provide a minimal flow between the pump suction and discharge system
9) Start parallel operating boiler circulating pumps with the stems of the discharge valves withdrawn to prevent overheating of the boiler water in the pump case.
7) Switch on power to the starter.
5.2 INITIAL STARTING-COLD BOILER CONDITION
8) Press the starter button on the control console and energise the motor for 5 seconds only.
In systems where the circulators are arranged in parallel, to avoid cavitation, sufficient circulators must be operated to limit the capacity per pump to a value where the N.P.S.H. required is less than the amount of N.P.S.H. available.
5. 1
SECTION 5 COMMISSIONING CAUTION: The motor runs up to full R.P.M. in appropriately one second. If the motor fails to start after five seconds, press the stop button and do not attempt to restart the circulator for 20 minutes.
12) When the stabilised: -
motor
temperature
has
a) Adjust the high temperature alarm setting to 10% above this point, or to 57°C, whichever is the lower. The trip setting must never exceed 60°C. b) Make adjustment to instrumentation as necessary.
9) After ten minutes pause, run the circulator for a further (2nd) five seconds. During this run, check the following:-
other
c) Check all flanges, glands and valves for leaks.
a) Motor Current (after ammeter has come off initial surge of current)
d) As the boiler water temperature increase, its specific gravity decreases and the amount of N.P.S.H., available increases. The temperature of the high pressure water to the heat exchanger may alter due to lower losses in the motor, or because of increased heat flow from the pump. NOTE: It is normal procedure to commission circulators separately, but if required, before the last circulator is stopped, the others may be energised and their recordings taken after each one is brought on-line.
b) Differential pressure - when the check valves open, the differential pressure should rise immediately to approximately 3 bars. NOTE: If the differential pressure does not rise, stop the motor immediately; it may be an indication that the motor is running in reverse. Reverse rotation will result in approximately 30% less head generated and about 10% more power absorbed than specified.
10) After a further (3rd) ten-minute pause, repeat operation (9).
5.3 STOPPING 1) Press the stop button on the control console. The run-down time is approximately 2.5 seconds.
11) After another (4th) ten-minute pause, energise the motor and run for twenty minutes. During this running period, carry out the following checks:-
2) Close the discharge valves.
a) Check the motor for vibration, using a vibration detector, several times and record reading for future comparison.
3) Maintain the low pressure cooling water supply to the heat exchanger. NOTE 1: If the circulator is to stand idle for some considerable time with the boiler cold, the low pressure cooling water to the heat exchanger may be turned off, especially on systems where the cooling water runs to waste.
b) Check for rubbing or excess bearing noise by holding a listening rod against the pump and motor case. c) Check the motor operating temperature at regular intervals. Initially it should rise several degrees then stabilise. If necessary, adjust the secondary cooling water flow after checking that the strainers are not obstructed.
NOTE 2: On hot boilers, and whenever the circulator is run, the low pressure cooling water to the heat exchanger must always be on.
d) Check, as the motor warms, that the high pressure circulation pipe entering the heat exchanger from the top of the motor becomes warmer than the high pressure circulation pipe from the bottom of the heat exchanger to the motor case. This indicates correct functioning of the heat exchanger.
CAUTION: If the circulator is to be idle for an extended period, and be subjected to freezing temperatures, make sure that provision is made to protect the motors from freezing (see Section 2.2.2.)
e) Check that motor current and differential pressure readings several times and record the readings.
5. 2
SECTION 6 OPERATION
CONTENTS
PARAGRAP H
PAGE
6.1
STARTING THE CIRCULATOR
6.1
6.2
SHUTTING DOWN THE CIRCULATOR
6.2
6.3
ROUTINE CHECKS AND OPERATIONAL CONDITIONS
6.3
6.4
FAULT FINDING
6.5
ILLUSTRATIONS
Figure 6/1
FAULT LIST CHART
6.6
6.0
SECTION 6 OPERATION
Any of the following conditions may exist when putting a circulator into service. Follow the relevant procedures below and refer to 6.3 for routine checks and operational fault action.
6) Ensuring the boiler is still full, energise the second duty circulator on line and run up to speed. 7) Perform the operational checks below. Refer also to Para. 6.3.
6.1 STARTING THE CIRCULATOR
a) Amperage. b) Motor cavity temperature on alarm thermometer.
6.1.1 Boiler Cold - Circulator Cold and Filled (Boiler Start-Up).
c) Differential pressure.
1) Ensure that the pre-start checklist, 5.1 is satisfied.
d) Low pressure cooling flow and temperature.
2) Vent the motor as follows: -
e) Vibration.
a) Release any air trapped below the suction by opening the by-pass valves and the filling valves.
f) Drum level. g) Valve and gland leakage. 8) Energising other motors: When the boiler differential pressure parameters require the other circulators to be energised: -
b) When air-free water is discharged through the vent valve, close vent valve. 3) Vent the pump as follows: -
a) Check that the differential temperature, between the pump case and boiler water in the downcomers, is within 28°C.
a) Open the vent valve. b) When air-free water is discharged from vent valve, close vent valve and filling valves.
b) Energise the other motors.
c) Open the stems of the discharge valves.
c) Close by-pass valves on the newly energised pump(s).
CAUTION: The pump must always be re-vented in this manner prior to starting when the drum pressure is below 3.5 kg/cm 2.
d) Perform the operation checks on the newly energised pump as detailed in para.6.1.1 (7).
6.1.2 Boiler Hot - Circulator Hot and Filled (Hot Standby)
NOTE: The motor starting procedure following is based on a normal boiler starting procedure where usually two circulators are initially operated with the remainder brought-on line as required.
NOTE: The low-pressure coolant to the heat exchanger must be on.
1) Check the differential temperature between the pump case and the boiler water in the downcomers.
4) a) On circulators that will not be energised, open the pump discharge by-pass valves. This ensures that as the boiler heats up, a flow passes from the discharge legs to the pump case and impeller etc.
CAUTION: The differential temperature between the pump case and the boiler water in the downcomers must not exceed 28 C. Nonadherence to this may cause thermal shocks and damage to occur. °
b) Check the motor temperature on the alarm thermometer; this should not exceed 49°C or be less than 5°C.
2) Energise the motor. 3) Close by-pass valves.
5) Energise the first motor. The current will drop from full starting current after a few seconds to approximately the value corresponding to the operating point on the makers test curve.
4) Check circulator operation as detailed in para.6.1.1 (7).
6.1
SECTION 6 OPERATION
6) Check the pump case temperature as the pump case is cooling to ensure that the cooling rate does not exceed 120°C per hour. If necessary, correct the cooling rate as follows:
6.1.3 Installation on a Hot Boiler NOTE: Not recommended for safety reasons – but not possible on this installation since no suction valves are fitted and hence pumps cannot be isolated.
6.2 SHUTTING CIRCULATOR
DOWN
a) Cooling rate too fast: - If the pump case cooling rate is too fast, slow the cooling rate by partially opening the by-pass valves as necessary.
THE
b) Cooling rate too slow: - If the pump case cooling rate is too slow, increase the rate by injecting a high pressure purge as detailed in Para. 6.3.8.
CAUTION Low pressure cooling water flow and motor temperatures must always be within the specified limits, whenever the circulator is on hot standby.
7) When the pump case has cooled to 45°C de-pressurise the circulator as follows: -
6.2.1 Boiler Hot - Circulator to go on Hot Standby
a) Ensure the pump discharge by-pass valves and shut-off valve are closed.
1) Press the stop button on the control console.
b) Slowly depressurise the circulator by closing the pump suction by-pass valve and partially opening the pump and suction leg vent valve.
2) Ensure that the low-pressure cooling line valves are open. 3) Open by-pass valves to provide circulation of high temperature boiler water through the pump casing, suction and discharge lines.
c) Open the motor cavity pressure gauge shut-off valves and check the pressure on the motor cavity gauge. When the pressure has stabilised, close the pump suction leg vent valve.
6.2.2 Boiler Hot - Circulator to be Isolated for Maintenance
d) Re-check that the pressure does not increase. Should it increase, check the following: -
1) Press the stop button of the control console to de-energise the motor.
i) Make sure that all valves between the circulator and high-pressure system are closed.
2) Close the stems on the discharge valves.
ii) De-pressurise the again, if necessary.
3) Close the pump jumper line service valves.
circulator
8) On completion of depressurising, the motor is ready for removal.
4) Crack open the pump suction bypass valves to prevent a vacuum forming in the pump case during the circulator cooling process.
CAUTION
The low pressure cooling water must be maintained until the motor has been separated from a hot pump case.
5) Maintain the low pressure cooling system to the heat exchanger, via the low pressure flowrator valves in the cooling pipes open until the motor has been separated from the pump.
6.2.3 Boiler Cold 1) Press the button on the control console. 2) Leave open the low pressure cooling water line valves.
CAUTION: Keep a close watch on the motor cavity temperature, should the temperature increase, apply a high-pressure purge as described in para. 6.3.8.
3) Pump discharge valves may be left open.
6.2
SECTION 6 OPERATION
6.3 ROUTINE CHECKS OPERATION CONDITIONS
3) If temperature increase continues and exceeds the 60°C - trip setting - and the cause cannot be detected or the condition corrected, refer to the relevant shutdown procedure in Para. 6.2. If necessary, blow down the boiler system or apply a high pressure purge to the motor. See 6.3.8.
AND
(Also see fault list chart)
6.3.1 Supply Current 1) Check the motor running current each shift. The current should be constant and comply with that specified in section 1.
a) After cooling and draining, remove and disassemble the motor and examine for worn bearings, blocked internal strainer, motor passages, auxiliary impeller and fouled cooling surfaces. In addition, leaks in the heat exchanger.
NOTE: High amperage readings or fluctuating motor currents indicate wear or partial seizure at the bearing or wear ring surfaces. This condition can cause vibration necessitating motor removal strip and re-installation.
4) Should the alarm sound whilst the circulator is on stand-by, start the circulator to accelerate internal high pressure cooling water flow. Check possible causes for temperature increase as above. The circulator should be tripped if the temperature exceeds 60°C and the shutdown / purge procedure 6.2 carried out.
6.3.2 Motor Temperature 1) During normal operation, the motor temperature should be checked at weekly intervals. The thermometer is originally set to initiate an alarm if the motor cavity temperature reaches 57°C and to deenergise the motor if the temperature reaches 60°C. If desired, the aforementioned alarm temperature settings may be lowered, on the temperature alarm thermometer, to suit normal operation but only after the boiler and circulator has been operated long enough to stabilise.
6.3.3 High Temperature Alarm and Trip Settings At weekly intervals check that the motor high temperature alarm setting does not exceed 57°C or 5°C above normal operating Temperature (whichever is the lower) and that the trip setting does not exceed 60°C. Re-set if necessary.
2) Immediately investigate the following possible causes for high temperature alarm sounding: -
6.3.4 Pump Head and Quantity 1) Check the total head generated by each pump at weekly intervals.
CAUTION Do not stop the motor.
2) Correct possible causes of decrease in head and quantity as follows: -
a) Check the low pressure cooling water supply for adequate flow, temperature vapour locks and leakage in piping (see 6.3.7.).
a) The gate valve in the circulating pump suction line and the check valve in the circulating pump discharge lines are not fully open. Check and adjust the setting as necessary.
b) Check the circulator for leaks from the motor casing, high pressure fill and drain cooling water connections, particularly the motor fill and purge line shut-off valves and the motor drain valves.
b) Discharge through the pump and suction leg vent or the pump casing and suction leg drain valves. Ensure both are closed.
c) Check that the cooling water strainers are not obstructed.
c) Low N.P.S.H., available due to reduced water level in the steam drum, changes in system pipework or system blockage. Check and adjust the number of circulators operating to suit until the fault can be corrected.
d) Check for indication of bearing damage (noise, vibration).
6.3
SECTION 6 OPERATION
d) Vent the pipe system to remove vapour locks.
f) Electrically induced vibration also a factor, i.e. Rotor bar breakage etc.
e) Power supply and reverse rotation checks are given in 5.5.1 (5) and 5.2 (9).
NOTE: When (e) is the cause, the motor must be removed, as detailed in section 7.2, before repairs can be undertaken.
f) Worn wear rings and a blocked or damaged impeller can be corrected only after removing the motor assembly from the pump case. Clearances are specified in section 1.
6.3.7 Low Pressure Cooling Water Supply Failure. If the cooling water to the heat exchanger is lost while the circulator is at operating temperature, the motor must be de-energised within five minutes and the suction and delivery valves closed as soon as possible.
6.3.5 Insulation Condition Before initially energising the motor and thereafter at monthly intervals, check the following: -
CAUTION Damage to the windings may occur if: a) the motor remains in operation after 5 minutes from the loss of cooling water. Or
1) The insulation resistance to ground of the motor leads. a) With the unit filled with water below 20°C or at normal local ambient temperature, the resistance measured at the terminal links, using a 1000V megger, must exceed 200 megohms.
b) if the cooling water is not restored before the motor temperature rises above 60°C.
NOTE: The insulation resistance of the stator winding varies with temperature and must always be measured cold 20°C or at normal local ambient temperature.
CAUTION Do not attempt to operate the motor by overriding the temperature controller trip mechanism and restore the low pressure cooling water as quickly as possible. Damage to the windings may occur if the cooling water is not restored before the motor temperature rises above 60°C.
2) Ensure that the interior of the terminal box is dry, especially the insulation projecting over the gland stems.
6.3.6 Vibration
NOTE: Before re-starting a circulator after an emergency shutdown, low pressure cooling water must be supplied to the pump to reduce the motor temperature to at least 38°C.
Check the circulators for excessive noise or vibration, which can be either hydraulic or mechanical in origin. Vibration should be monitored and recorded daily. If a permanent vibration transducer is not installed, check at weekly intervals using temporary pick-ups. If the reading increases, check for the following causes: -
6.3.8 High Pressure Purge Supply To Motor. On some boiler installations the motor fill and drain connection may be connected to a high pressure cold purge system which can be used for emergency motor cooling and to protect the motor during boiler cleaning. During normal operation this purge supply must be isolated with a double isolation valve fitted to the motor, as any leakage or reverse flow from this point can result in motor overheating, winding and / or bearing damage. (Reverse flow totalling no more than 2 – 3 litres is sufficient to cause damage).
a) Cavitation due to low N.P.S.H., as described in 6.3.4. b) Unequal settings of the discharge valves. Check and re-set in the fully open position. c) Incorrect directional rotation described in section 5.2, para. 9.
as
d) Excessive pipe strain on the pump casing due to expansion or inadequate support of pipes. Eliminate any strain by providing adequate support. e) Damaged or unbalanced rotor or impeller, worn bearings, excessive end float or incorrect impeller setting.
6.4
SECTION 6 OPERATION NOTE: Continuous purging of the motor during operation is recommended only during boiling-out and acid cleaning. A purge rate of 3.8 litres / min., is normally sufficient to prevent the ingress of harmful fluids and solids into the motor.
If the boiler is “laid-up” under a nitrogen blanket, take necessary precautions to prevent damage to the motor through gaseous water. Any pump start-up, when the boiler is in this condition, must be undertaken and initial start and the full fill and vent procedure, as detailed in section 4.7, must be followed.
1) Flush down the fill and purge system to ensure the line is clean.
6.3.10 Boiler Cleaning
2) Check that the low pressure cooling water supply valves are open.
During any boiling-out or acid cleaning operation of the boiler, the de-energised circulators must be isolated completely prior to introducing any chemicals to the boiler. The circulators must be continuously purged with clean cool water at a pressure of approximately 7 bar, in excess of the existing drum pressure to eliminate infiltration of contaminated water into the bearing and motor components.
3) Introduce high pressure purge through the filling valves. Check that the purge temperature does not exceed 49°C and that the purge pressure is above the boiler pressure.
6.3.9 Extended Shut-Down When the circulator remains shutdown for an extended period: -
CAUTION Severe damage can be caused if acid is allowed to enter the motor. If contamination from acid cleaning is suspected, motor must be purged immediately with clean water and inspected for damage.
1) Check regularly that it remains full of water. 2) Run the circulator for a minimum of ten minutes every two months. CAUTION If the motor is to be subjected to extreme low temperature, the motor must be prevented from freezing, see section 2.2. (5)
6.4 FAULT FINDING Refer to the fault list chart that follows.
6.5
SECTION 6 OPERATION
Fi ure 6/1 Fault List Chart
6.6
SECTION 7 MAINTENANCE
CONTENTS
PARAGRAP H
PAGE
7.1
INTERNAL INSPECTION
7.3
7.2
MOTOR REMOVAL
7.3
7.3
DISASSEMBLY
7.4
7.4
INSPECTION OF COMPONENTS
7.16
7.5
ASSEMBLY NOTES
7.27
7.6
ASSEMBLY
7.29
7.7
RE-INSTALLATION OF MOTOR
7.42
PARTS LIST – GENERAL
7.43
ILLUSTRATIONS
FIGURE 7/1
MOTOR REMOVAL
7.2
FIGURE 7/2
MAIN IMPELLER REMOVAL
7.5
FIGURE 7/3
TERMINAL BOX
7.6
FIGURE 7/4
UP - ENDING THE MOTOR
7.7
FIGURE 7/5
TYPICAL WORKING PLATFORM
7.8
FIGURE 7/6
MOTOR COVER AND FILTER REMOVAL
7.9
FIGURE 7/7
THRUST BEARING
7.10
FIGURE 7/8
COVER – END JOURNAL BEARING ASSEMBLY - REMOVAL
7.11
FIGURE 7/9
ROTOR ASSEMBLY - REMOVAL
7.12
FIGURE 7/10
TERMINAL GLAND REMOVAL
7.13
FIGURE 7/11
STATOR ASSEMBLY - REMOVAL
7.14
FIGURE 7/12
JOURNAL BEARING TILTING PADS - REMOVAL
7.15
FIGURE 7/13
JOURNAL BEARING CLEARANCE
7.16
7.0
SECTION 7 MAINTENANCE
FIGURE 7/14
JOURNAL BEARING SLEEVE - REMOVAL
7.17
FIGURE 7/15
THRUST BEARING CLEARANCE
7.18
FIGURE 7/16
IMPELLER AND CASE WEAR RING
7.19
FIGURE 7/17
DETAILS OF TAPING HOOK
7.22
FIGURE 7/18
DETAILS OF TAPING NEEDLE
7.22
FIGURE 7/19
OUTER COIL TAPING
7.23
FIGURE 7/20
INNER COIL TAPING
7.24
FIGURE 7/21
TYPICAL KNOT SEALING
7.26
FIGURE 7/22
ASSEMBLY OF FLANGE STUDS
7.27
FIGURE 7/23
WIRE LOCKING
7.28
FIGURE 7/24
JOURNAL BEARING - ASSEMBLY
7.29
FIGURE 7/25
STATOR ASSEMBLY
7.30
FIGURE 7/26
JOURNAL SLEEVE
7.31
FIGURE 7/27
TERMINAL GLAND ASSEMBLY
7.32
FIGURE 7/28A
COVER END BEARING ASSEMBLY
7.33
FIGURE 7/28B
COVER END BEARING ASSEMBLY
7.33
FIGURE 7/28C
COVER END BEARING ASSEMBLY
7.34
FIGURE 7/29
END FLOAT CHECK
7.35
FIGURE 7/30
MOTOR COVER AND FILTER ASSEMBLY
7.37
FIGURE 7/31
TERMINAL BOX
7.38
FIGURE 7/32
TERMINAL LINK INSULATION
7.39
FIGURE 7/33
BURSTING DISC DETAILS
7.40
FIGURE 7/34
IMPELLER SETTING
7.41
FIGURE 7/35
GENERAL ARRANGEMENT
7.47
FIGURE 7/36
SECTIONAL ARRANGEMENT
7.48
FIGURE 7/37
TERMINAL BOX ARRANGEMENT
7.49
FIGURE 7/38
TOOL KIT LIST
7.50
7.1
SECTION 7 MAINTENANCE
Fi ure 7/1 Motor Removal
7.2
SECTION 7 MAINTENANCE
b) Immediately secure temporary cooling water hoses to the inlet and outlet connections of the heat exchanger to maintain a low pressure cooling water flow within the heat exchanger.
NOTE 1: Some of the illustrations shown are typical only and not necessarily specific to the circulator described, i.e. motor proportions and number of studs etc., but indicate generally the basis of the unit breakdown.
c) Maintain cooling water until the motor is separated from the pump.
NOTE 2: For items not annotated on the drawings within the text refer to the Main Sectional Arrangement at the rear of the Section.
CAUTION: The low pressure cooling water flow, and motor temperature must be maintained within the specified limits, whenever the motor is in contact with the pump case.
NOTE 3: A tool kit is supplied with each circulator contract, containing specialised tools necessary for the disassembly and assembly of the motor.
4) Check the pressure gauges to ensure that the circulator is depressurised. 5) Make sure that the discharge valves, the suction valve, the by-pass valves and the shut-off valves are closed to isolate the circulator from the boiler and fill system.
7.1 INTERNAL INSPECTION Internal inspection of the circulator should be carried out to the recommendation of the station maintenance authority.
6) Drain the pump casing. WARNING: Never drain the pump casing through the motor fill & drain line as this could cause contamination of the motor.
Partial inspection of the internal filter and thrust bearing is possible in-situ after removal of the motor cover.
7) Fit the removable lifting lugs to the welded brackets on the motor case.
WARNING: Inspection must only be carried out with the circulator isolated from the electrical supply, depressurised and the motor cover removed as in Section 7.3.4.
8) Set up two chain hoists and rigging, of sufficient capacity for each to take the full weight of the motor, and connect to the lifting lugs.
A full inspection requires the motor assembly to be removed as described below.
WARNING: Normally two hoists are used for removing the motor and because the load can shift from one hoist to the other during the removal, each hoist must be capable of taking the full weight of the motor.
7.2 MOTOR REMOVAL (FIG. 7/1) WARNING: Before removing the motor, the circulator must be completely isolated from the system, depressurised and cooled as described below.
9) Take the initial strain of the motor. CAUTION: The motor must be removed from the pump casing without a break in the sequence (9) and (11).
7.2.1 Motor Removal
1) Isolate the electrical supply; disconnect all instrument cables from the motor identifying the connections and leads.
10) Loosen the pump/motor flange stud nuts in accordance with the hydraulic stud tensioning instructions - section 8.
2) Remove the terminal box covers and disconnect the external power supply cables from the terminal box as described in 7.3.4, identifying each lead for reassembly.
CAUTION Always double check that the motor and pump case are cooled and depressurized before loosening the studs nuts.
3) If hoses are not fitted in the low pressure cooling system, adjacent to the heat exchanger, with sufficient slack to allow the motor to be separated from the pump case, fit temporary hoses as follows:a) Close the low pressure cooling shut-off valves.
11) Disconnect the fill and drain line upstream of shut-off valve if there is not sufficient play in the line to permit motor removal.
water
7.3
SECTION 7 MAINTENANCE
12) Remove the flange stud nuts and lower the motor clear of the pump casing, keeping the flange faces parallel until the impeller is clear of the pump casing.
2) To remove the wear ring, remove the six screws securing the wear ring inside the pump casing. Carefully lower the wear ring from its location within the casing.
13) When the impeller is clear of the pump case, check the motor cavity temperature. When o the temperature falls below 54 C remove all instruments and store safely.
Lower to ground level, and store in a safe place for inspection. 7.3.2 Impeller (Fig. 7/2)
1) Unlock the punch marks and remove the impeller cap screw.
14) Lower the motor to the floor. 15) Drain the motor via the drain valve and remove the valve and pipework
2) Remove the LEFT-HAND threaded impeller nut using the special spanner and tommy bar provided in the tool kit.
16) Remove the heat exchanger from the motor, in accordance with site procedures, as described in 7.2.1.
NOTE: Do not use any leverage in the water passages of the impeller to oppose force exerted on the special spanner; the weight of the rotor will oppose rotation if the tommy-bar is given a few heavy blows with a lead faced hammer. If the nut shows any tendency to seize on the shaft, do not continue to exert force, but drill and split the nut to remove.
CAUTION: To prevent damage never stand or turn the motor on either the drain valves or terminal box.
17) Lower the motor to the horizontal position to give access to the terminal box, remove the lifting tackle and cover all joint faces and openings with clean rags.
3) Fit the puller, provided in the tool kit, to the tapped holes in the top of the impeller boss, using the applicable studs and nuts in the tool kit. Withdraw the impeller from the motor shaft.
18) If necessary, transport the motor to a working area where adequate facilities are available for disassembly, inspection and maintenance. 7.2.1 Heat Exchanger Removal
4) Withdraw the impeller washer and remove the impeller key.
NOTE: As the heat exchanger is welded to the motor case via the interconnecting pipework, removal of the heat exchanger is at the discretion of, and the procedure will be determined by, the senior station engineer.
5) Immediately refit a serviceable impeller nut to permanently protect the shaft threads. 7.3.3 Baffle Wear Ring
Examine the baffle wear ring. If damaged, remove the socket headed cap screws and lock washers. Remove the wear ring for a fuller inspection or renewal
Check the heat exchanger during the first motor maintenance removal for build up of sediment in the shell base; this will provide a guide to any future attention that may be required.
7.3.4 Terminal Boxes (Fig. 7/3)
1) Remove the nuts and washers from the studs and remove the terminal box cover.
7.3 DISASSEMBLY
2) Remove the nuts and washers from the terminal studs.
CAUTION: Lifting tackle must not be attached to the protruding rotor shaft nor must the shaft be subject to any shock loads. The motor must be adequately supported before and during any disassembly.
3) Identify the motor supply cable links for reconnection. 4) Carefully cut the insulation from around the cable connections and links.
7.3.1 Case Wear Ring
CAUTION: Do not damage the link insulation.
1) The case wear ring can be left in place, bolted inside the pump case.
5) Remove the washers and the nuts from the terminal stem as the link is removed.
7.4
SECTION 7 MAINTENANCE
6) Remove the nuts and washers from the terminal box support studs. Using lifting tackle, lift off the terminal boxes and remove the gaskets.
NOTE: A small metal cover should be fabricated and placed over the terminal stems to protect them during motor repair.
Fi ure 7/2 Im eller Removal
7.5
SECTION 7 MAINTENANCE
Fi ure 7/3 Terminal Box
7.6
SECTION 7 MAINTENANCE
Fi ure 7/4 U -Endin the Motor
7.7
SECTION 7 MAINTENANCE
7.3.5 Motor Cover and Filter (Fig. 7/6)
1) Using two cranes and lifting tackle attach one with shackles to the motor cover and the other via a sling around the motor flange neck. Lift and up-end the unit as depicted Fig. 7/4 until the motor is vertical, with the motor cover uppermost. Lower the motor pump flange on to a suitable building stand; a typical building stand is shown in Fig. 7/5. Support the rotor shaft beneath the stand using a screw or hydraulic jack. Care must be taken to avoid damaging the shaft or flange faces. If a pit is not available, erect a suitable working platform, similar to that depicted in Fig. 7/5. CAUTION: Firmly support the impeller end of the rotor shaft on a suitable wooden block when placing the motor on the stand and jack so that when the thrust nut is removed during a subsequent operation, the rotor will be adequately supported.
2) Mark the cover relative to the motor case to ensure correct alignment on reassembly. 3) Using the stud tensioning equipment (Section 8), release the tension of the motor cover nuts and remove the nuts. 4) Attach the lifting tackle and carefully remove the motor cover from the motor case. 5) Remove the flexitallic spiral wound gasket and before discarding, inspect the gasket for any unusual markings or depressions that indicate a seat dressing is required. 6) Remove the filter by removing the hexagonheaded screws and lock washers.
Figure 7/5 Typical Working Platform
7.8
SECTION 7 MAINTENANCE
Fi ure 7/6 Motor Cover and Filter Removal
7.9
SECTION 7 MAINTENANCE
Fi ure 7/7 Thrust Bearin
7.3.6 Thrust & Reverse Thrust Bearing
3) Remove the split pin and loosen the thrust nut using the thrust nut spanner provided in the tool kit.
(Fig.
7/7) CAUTION: Ensure that the impeller end of the rotor shaft is supported firmly. This will prevent damage to the rotor upon removal of the thrust nut. When cutting removing locking wire, ensure that no wire is permitted to fall into the windings.
a) Remove the thrust nut - right handed thread – and the spacer washer. b) Lower the jack ram, sufficiently to lower the rotor, leaving the thrust disc sitting on the thrust pads. c) Remove the thrust disc, taking care not to damage the running surfaces on the disc. d) Alternatively, use the thrust disc puller, to remove the thrust disc from the shaft.
1) Remove the reverse thrust housing, complete with reverse thrust wear ring as follows: a) Remove the socket-headed cap screws and lock washers securing the reverse thrust housing to the bearing housing.
4) Remove the thrust key. 5) Remove the thrust seat as follows:a) Remove the socket-headed cap screws and the spring washers securing the seat to the bearing housing.
b) Lift off the reverse thrust housing complete with the composite reverse thrust wear ring. Lower the jack.
b) Lift off the thrust seat complete with thrust pads.
2) Remove the thrust disc assembly as follows: a) Set up the jack, with ram extended beneath the rotor shaft and floor.
7.10
SECTION 7 MAINTENANCE
Fi ure 7/8 Cover – End Journal Bearin Assembl - Removal
7.3.7 Cover
End Journal Assembly (Fig. 7/8)
2) Match-mark the cover end bearing housing and the motor case to ensure that they are refitted in their original radial location.
Bearing
1)
3) Remove the bearing housing securing screws and lock washers.
a) Remove the locking wire and the stator lock ring hexagon headed screws.
4) Attach eyebolts and lifting tackle to the cover end bearing housing and lift the housing, complete with the journal bearing assembly, to just above the motor casing.
b) Push down the stator lock ring sufficient ly to permit split ring to be prised out of its groove. c) Remove the split ring from its casing groove, using screwdrivers as levers.
5) Lower the bearing housing and remove and discard the `O` ring.
d) Withdraw the stator lock ring, using screws as lifters, from the motor case.
6) Place the housing in a clean and safe place for subsequent disassembly.
7.11
SECTION 7 MAINTENANCE 7.3.8 Motor Shaft (Fig. 7/9) 7.3.9 Terminal Gland Removal (Fig. 7/10)
1) Fit an eyebolt, supplied in the tool kit, and lifting tackle to the rotor shaft as indicated. With an exact vertical lift, slowly lift the rotor out of the stator, taking particular care not to damage the cable ends whilst doing so.
1) To facilitate re-assembly, identify each terminal stem body and its respective position. CAUTION Make sure that the gland moulding does not turn with the gland nut by holding the moulding stationary using a clamp connector and the connecting link.
2) Lower the rotor into the horizontal position and position it carefully on to wooden 'V' blocks at floor level. Fit suitable protection, i.e. clean rags, over the journal sleeves. Refit the thrust nut to protect the threads.
2) Remove the nuts and link from the terminal block. Unscrew the gland nut and tap the connector lightly until the gland assembly can be carefully drawn out of the motor case. 3) Remove the gland nuts from two of the stems and placed on the third stem. 4) Replace the clamp connector over this stem and undo the cable gland nut. This action will draw the gland assembly from the motor case. 5) Remove the inner casing & the ‘C’ shaped support ring. The two belleville washers and back up sleeve remain on the cable. NOTE: The terminal gland stems are moulded on to the stator windings in a continuous waterproof sheath, which must not be broken or damaged CAUTION Never hammer the end of the stem if the assembly is tight, as this will damage the moulding.
6) Remove and discard the 'O'-ring from the inner casing neck. 7) Feed the remainder of the gland moulding and the cable assembly through the gland body into the motor casing. 8) Remove the ‘O’ rings and back up rings from the inner casing. 9) Suitably tape the terminal stems to prevent them from damage and lay them over the case flange. 10) Protect the cables from sharp corners.
Figure 7/9 Rotor Assembly - Removal
7.12
SECTION 7 MAINTENANCE
CAUTION: Protect the chamfer on the pump side of the bearing housing from damage, as this will affect alignment of the rotating assembly within the motor case.
5) Mark the stator shell and the pump-end bearing housing, so that the slot in the housing for the anti-rotation peg and the stator winding leads can be correctly aligned upon assembly. (Fig. 7/25). 6) Fit an eyebolt, sling and tackle, to the pump end bearing housing, and take the weight of the housing. 7) Remove the socket-headed cap screws and lock washers. Draw the bearing housing away from the stator shell. 8) Fit the lifting tackle to the cover-end bearing housing. Take the weight of the housing; remove the temporary fitted screws and carefully ease the housing from the stator shell. Further dismantling of the stator assembly is unnecessary unless the motor is to be rewound. If rewinding is necessary, contact Hayward Tyler.
Fi ure 7/10 Terminal Gland
7.3.11 Heat Exchanger
Check the heat exchanger during the first maintenance removal for build up of sediment in the shell base; this will provide a guide to any future attention that may be required.
7.3.10 Stator Shell and Bearing Assemblies
(Fig. 7/11)
De-scale and inspect the heat exchanger as follows:-
1) Place the cable leads within the stator bore. 2) Using guide rods temporarily re-fit the cover end bearing housing in position on the stator shell. Re-fit the housing screws and tighten.
1) Remove the inlet/outlet and return covers from the heat exchanger shell. Discard the gaskets.
3) Attach lifting tackle to the bearing housing eyebolts. With an exact vertical lift, slowly and carefully withdraw the stator assembly out of the motor case.
2) Using cleaning rods and a metal brush, remove all deposits from inside the tubes of the shell and from each end cover. 3) Inspect generally for good order of the heat exchanger.
4) Lower the stator and support it horizontally on wooden blocks placed at floor level. Ensure that the tapped hole for the eyebolt (used in lifting the pump end bearing housing) is located at the top centre.
4) Clean the mating faces of the shell and return cover and inlet/outlet cover. Fit new gaskets to their respective ends of the shell. 5) Bolt up the end covers with the existing bolts and nuts. 6) Pressure test the heat exchanger for adequate sealing.
7.13
SECTION 7 MAINTENANCE
Figure 7/11 Stator Assembly - Removal
7.14
SECTION 7 MAINTENANCE
Figure 7/12 Journal Bearing Tilting Pads - Removal
7.15
SECTION 7 MAINTENANCE
c) Journal Bearing Clearance
7.4 INSPECTION OF COMPONENTS
i) Place the tilting pads in their correct sequence on their corresponding journal sleeve and clamp firmly in position, using large hose clips, as shown.
7.4.1 Journal Bearing Tilting Pads (Fig. 7/13)
The following procedure applies to both the pump end and the cover end bearing housings.
ii) Measure the dimension across the pivots of each opposing pair of pads to determine the average dimension.
NOTE: Pads must be kept in their sets and each set identified with its original bearing housing and position in the housing for correct reassembly
NOTE: Do not use feeler gauges between the pads and sleeve due to the risk of damage to the sleeve and the inherent inaccuracy of this method.
1) Remove the securing ring screws and lock washers from the applicable bearing housing.
iii) Subtract this dimension from that of the inside dimension of the mating bearing ring bore. Record the result and compare it with the bearing clearance limits detailed in Section 1. Technical Data.
2) Remove the securing ring, cover end or pump end. 3) Identify the journal tilting pads with their respective housings and mark the sequence of removal in a counter clockwise direction, 1 to 6.
iv) If the clearance is excessive, fit a new set of tilting pads and a new journal sleeve.
4) Withdraw the tilting pads, noting the location of the pivot and direction of arrows stamped on the rear side.
v) Remove the clips and tilting pads from the journal and suitably protect the journals and pads until required for reassembly.
5) Remove the bearing ring. 6) Remove the two anti-rotation stop pegs from each bearing ring. 7) Clean and dry all components (except composite parts). 8) Inspect all components as follows: a) Tilting Pads i) Check the surface for scoring or breakdown of the composite. Slight scoring is permissible but if the composite surface is pitted or laminating renew or return the complete set to Hayward Tyler for possible reclamation. NOTE: Under no circumstances renovate the pad surfaces with Carborundum Paste or Emery Cloth.
ii) There should be no evidence 'brinelling' of the tilting pivot.
of
iii) Ensure that the edge of the working face has a 3 mm radius. b) Bearing Rings Check the seat surface for brinelling and renew if grooved on the pad location.
Fi ure 7/13 Journal Bearin Clearance
7.16
SECTION 7 MAINTENANCE
4) Inspect and record findings as follows: -
7.4.2 Journal Bearing Sleeves (Fig. 7/14)
a) Thrust Pad
1) Very slight scoring or scratching of the journal sleeve is permissible but if excessive or cracked, the sleeve must be removed.
i) Slight scoring on the face is acceptable, but if excessive, the pad must be either renewed or reground within the limits of the end float (see Section 1) to a surface finish of 0.15 micrometers.
2) If the journal sleeve is to be renewed, screw the journal locking screw into the shaft and carefully mill through the sleeve along the keyway until the sleeve splits.
ii) The thickness of the pads must be uniform and parallel within .01 mm. Evidence of brinelling on the pivot is unacceptable. The radius on the edge of the face should be 1.5mm.
3) Remove the sleeve and the journal key. Protect the sleeve seat until the new sleeve can be fitted as Para 7.6.2.
b) Thrust Pad Stop i) Examine for fretting on the shank and head. If evident, re-new. c) Thrust Seat i) Examine for brinelling under the pivots. If evident, re-new. d) Thrust Disc i) Check by lightly tapping that the composite facings are correctly bonded to the metal disc. Renew the disc assembly if the composite plate is loose i.e. if a ‘hollow’ sound is heard. ii) Check the composite face is not badly worn or scored. iii) With the thrust disc mounted on a suitable mandrel, check that the working faces for both forward and reverse thrusts are flat to within .025 mm. e) Auxiliary Impeller (Fig. 7/15) i) Measure and record the outside diameter of the auxiliary impeller skirt. ii) Ensure that the water passages are clear. NOTE:(1) The auxiliary impeller is an integral part of the thrust disc. NOTE:(2) All parts containing composite must be submerged until assembly.
Fi ure 7/14 Journal Bearin Sleeve - Removal
f) Reverse Thrust Wear Ring. i) Measure and record the bore of the composite reverse thrust wear ring.
7.4.3 Thrust and Reverse Thrust Bearing (Fig.
7/15)
ii) Subtract the outside diameter of the thrust disc skirt from the bore of the wear ring to establish the clearance.
CAUTION: Thrust bearing pads must be retained in sets and each pad numbered consecutively in a clockwise sequence, as viewed from the thrust end.
iii) Compare the clearance obtained with that specified in Section 1, Technical Data.
1) Remove the split cotter pin from the thrust pad stops.
iv) Re-new the reverse thrust wear ring if either the clearance is excessive or if the composite has deteriorated.
2) Carefully remove the thrust pads from the thrust seat.
v) To remove the wear ring, remove the philidas nuts and the cap screws
3) Clean and dry all components.
7.17
SECTION 7 MAINTENANCE
Fi ure 7/15 Thrust Bearin Clearance
7.4.4 Impeller and Case Wear Rings (Fig.7/16)
1) Clean the impeller and the case wear rings and check them for damage.
e) Allow the wear ring to cool and shrink onto the impeller.
2) Subtract the impeller wear ring outer diameter from the case wear ring bore, allowing for any temperature difference and compare with the clearance specified in Section 1, Technical Data
f) Drill new grub screw holes using a Tungsten Carbide tipped type drill. g) Tap for, and fit, new grub screws. Punch lock on the inside of the impeller. h) Machine the grub screws flush with wear ring.
3) Check the hardened surface of the impeller wear ring.
i) Check the impeller wear ring for concentricity. If eccentric, machine the wear ring, in situ, a maximum of 0.25mm. The maximum wear ring clearance permitted is 2.03mm.
4) If necessary, renew the impeller wear rings as follows:a) Carefully machine away the old ring without damaging the impeller. If necessary, clean up the wear ring seating.
j) Re-balance the impeller. Refer Hayward Tyler for the balancing data.
b) Heat the new impeller wear ring until it is considered sufficiently expanded to slide on the impeller rim. Heat by playing a gentle gas flame round the rim.
to
5) If the impeller has been damaged or repaired, always check the dynamic unbalance. 6) If the pump case wear ring requires renewal, fit the new ring and secure using the six socket head cap screws and lock washers. Tighten the screws in accordance with the torque figures detailed in Section 1.
c) Lift the heated wear ring on to the impeller rim, using suitable heat resistant tongs. d) Tap the wear ring down to its position on the impeller.
7.18
SECTION 7 MAINTENANCE
Figure 7/16 Impeller & Case Wear Ring
7.19
SECTION 7 MAINTENANCE
3) That there is no apparent damage to the windings or cable leads.
7.4.5 Rotor Assembly
1) Clean and inspect for damage all keys, threads, keyways and sleeve locking screws, located on the rotor shaft.
4) White insulating sleeve, (see detail para.7.6.6) is below the level of the XLP gland moulding. The difference when new is approximately 0.65mm. If the nylon and XLP surfaces are flush, renew the complete tail moulding.
2) Fit the impeller washer, impeller key, impeller, and impeller lock screw on to the pump end of the shaft.
5) Immerse the complete stator in water of a temperature below 20ºC ensuring that on the lead cables the water reaches no higher than the inner face of the gland moulding.
3) Fit the thrust disc key, thrust disc, spacer washer and thrust nut on to the thrust end of the shaft.
6) Check and record the insulation resistance using a 1000V megger. If the resistance is below 5 megohms, check carefully for breaks in the insulation. If a visual check is insufficient to locate a fault, check for the fault as follows: -
4) Thoroughly clean the rotor shaft. 5) Check the shaft for run-out, as follows:a) Place the shaft on rollers that locate between the journal sleeves and the short circuit rings. b) Check the run-out along the shaft and laminations; maximum run-out permissible 0.05mm.
a) With the stator still immersed in water, using a Flash-Tester, apply a voltage at one third operating volts and gradually increase until a visual indication of the fault location appears. This should occur before the full operational voltage is reached, but if it does not, the voltage may be increased to 1.5 times operating voltage for a period not exceeding one minute. For operating voltage, refer to Section 1 - Technical Data.
c) Check the run-out at the impeller wear ring; maximum run-out permissible 0.125mm. d) Check the run-out at the thrust disc; maximum run-out permissible 0.10mm. e) Check the run-out at the journal bearing sleeves: maximum run-out permissible 0.025mm.
NOTE DC high voltage testing of old windings at values higher than 150% rated volts is not recommended as further damage to aged windings can occur causing premature failure.
6) Check that the laminations, short circuit ring, rotor bars and balance rings are undamaged. NOTE: If any components on the rotating assembly have been damaged, or renewed, the complete rotating assembly must be dynamically balanced within 5000 gm.mm.
7.4.7 Motor Case and Cover
Check the condition of the following: -
7) Take the rotor assembly off the rollers and remove the impeller and thrust disc along with their connecting components.
1) The weld round the anti-rotation peg. 2) The motor case and cover flanges.
8) Protect all parts of the rotor until required for assembly.
3) The baffle wear ring. With normal usage this wear ring should not require renewal throughout the life of the unit. However, if it is damaged, remove the screws and the tab washers and remove the wear ring.
7.4.6 Stator Assembly
Unless an electrical fault is suspected, a visual inspection of the windings, followed by an insulation check, fulfils normal requirements but the following checks should be made:
4) Faces of all pump case and motor cover nuts for freedom from damage and burrs. 7.4.8 Terminal Boxes (Fig. 7/37)
1) No slackness exists in wedges located at the bottom of the stator slot behind the cables.
Check that the bursting discs are not ruptured and the inside of the terminal box is dry.
2) Windings coils are taped together and secured to the support brackets. Damaged winding tapes must be renewed to the procedure given in para. 7.4.9.
7.20
SECTION 7 MAINTENANCE 7.4.9.3 Taping Outer Coils (Fig. 7/19)
7.4.9 General
Using one piece of Heat-set Nylon tape 18mm wide x 0.5mm thick approximately 4.5m long, bind and anchor the outer windings coils at the stator end as follows: -
Winding tapes must only be renewed with Heat Set Nylon 66 braided tape 18mm wide x 0.5mm thick. The taping knots must be secured with an epoxy resin adhesive, using only those grades specified (see 'knot sealing'). No other grade of adhesive is permitted.
NOTE: Take extreme care when retaping not to damage the winding cable insulation covering.
It is essential that the tapes are thoroughly dry when the adhesive is used in sealing the knots because if the tapes are damp, the adhesive will not adhere successfully. The adhesive should cover the knot completely but must not be indiscriminately smeared in the general vicinity of the tape.
1) Place a smooth wedge of wood between the stator shell and the outer coil to hold the end turns away from the shell and to allow the taping hook or needle to be inserted and slid through.
7.4.9.1 Tools (Figs. 7/17 & 7/18)
2) Insert the taping hook between the stator shell and coil towards the end plate. Bend the shank of the hook as necessary to be seen or felt behind the coil.
The following locally made tools should be used to assist the tapering operation. 1) Make one taping hook (Fig. 7/17), from ∅2.4mm x 460mm long gas welding rod as follows:
3) Using the hook tool, hook the tape up from the bottom and from behind coils, leaving at least 250mm of tape free at the beginning of the band for knotting purposes.
a) Bend the rod about 25mm from the end at a 90 degrees angle. File and emery cloth smooth.
4) Starting from the centre of the coil, spiral wrap the tape around the conductors to form a band of two 50% overlaps of tape fully 50mm wide to cover the Nitrile rubber insets in the coil. Sufficient tension should be applied to hold the conductors together.
b) Form the opposite end into a loop handle giving the tool an approximate length of 300 to 350mm 2) Make one flexible needle (Fig. 7/18), about 255mm long, from ∅0.8mm steel or copper wire.
5) Continue taping the coil to the anchorage bracket, welded to the stator end plate, or winding support ring, whichever is fitted, using four spiral half-tape (50%) overlaps. (i.e. eight thickness’) of Nylon tape. The band should again be made 50mm wide with enough tension to prevent movement of the coils.
3) Bend the wire double leaving a small loop and solder the ends of the loop together. a) File and smooth all edges4) Wooden wedges (various sizes) smooth with no sharp edges.
6)
7.4.9.2 Preparation
a) Tie the ends of the tape into a square (reef) knot so that the knot is positioned on the outer edge of the coil as far as is practicable and so that if pressed into the coil it would be between two cables, rather than pressing on the top of one.
1) The winding coils are known as first and second and windings. The first (Fig. 7/19) being nearest the shell, the second (7/20) being nearer the bore. 2) Remove the existing wrapping tape from the coils and ensure that the nitrile rubber inserts are in between the layers in the centre of the coils.
b) Cut the tape ends protruding from the knot to 25mm long. c) Seal the knot with the approved epoxy resin adhesive to prevent the knot from coming loose in accordance with para. 7.4.9.6.
3) Thoroughly wash out the stator to remove any foreign debris, such as magnetite or rust deposits, from the windings.
7) Remove the wooden wedge(s), and any taping tools.
4) Dry out the stator windings using a hot air fan heater positioned nearby; this is to ensure that the new tape is kept clean and dry for knot sealing.
7.21
SECTION 7 MAINTENANCE
k o o H g n i p a T f o s l i a t e D 7 1 / 7 e r u g i F
7.22
e l d e e N g n i p a T f o s l i a t e D 8 1 / 7 e r u g i F
SECTION 7 MAINTENANCE
Fi ure 7/19 Outer coil Ta in
7.23
SECTION 7 MAINTENANCE
Fi ure 7/20 Inner Coil Ta in
7.24
SECTION 7 MAINTENANCE
5) Bind and anchor the other two inner coil bundles in a similar manner.
7.4.9.4 Taping Inner Coils (Fig. 7/20)
Bind the inner winding coils as follows:-
7.4.9.5 Taping the Lead Cables
1) Remove the damaged binding tape from one of the inner coils.
Arrange and tape the connections and lead cables in groups of three - two in a clockwise direction and one in an anti-clockwise direction, as follows:
2) Ensure that the nitrile rubber inserts are in position between the layers and the centre of the coil.
1) Anchor the cables in position to the windings with four spiral half-laps of Heat-Set Nylon 66 braided tape 18mm wide x 0.5mm t hick.
3) Bind the second coil bundles, using a length of Heat-Set Nylon 66 braided tape 18mm wide x 0.5mm thick, approximately 2.75m long, as follows:-
2) Make the band 50mm wide and tie the ends into a square (reef) knot.
a) Thread one end of the tape on the needle tool.
3) Cut the tape end to 25mm long and seal the knot with an epoxy resin adhesive to prevent it becoming loose. the adhesive should completely cover the knot.
b) Leave at least 250mm of tape at the beginning of the band for knotting purposes.
4) Make the last binding on the lead cable 300mm from the respective holes in the bearing housing.
c) Bind the coil bundle to form a 50mm wide band of two spiral half overlaps, four layers thick. d) Tie of the band with a square (reef) knot on the outside of the band , as shown, and so that the final anchorage tape will not press the knot into the coil bundle.
7.4.9.6 Knot Sealing (Fig 7/21)
1) Either of the following adhesives must be used to prevent the knots becoming loose. a) Fast-setting epoxy resin adhesive:
e) Cut the bundle tape end 25mm from the knot and seal the knot with epoxy resin adhesive, as described in para. 7.
AV/HV115, as supplied by CIBA-GEIGY (UK) LTD. NOTE: A handipack kit comprising two tubes; one resin, the other hardener, known as 'Rapid Araldite' in the United Kingdom, is generally equivalent to the above specification.
4) Anchor tape the inner coil bundle to the stator anchor bracket, or winding ring, whichever is fitted, with a length of heat-set Nylon 66 braided tape 18mm x 0.5mm thick, as follows:a) Leave at least 250mm of tape at the beginning of the band for knot tying purposes.
b) Fast-setting epoxy resin adhesive XD738 as supplied by CIBA-GEIGY (UK) LTD., available in bulk containers.
b) Bind the coil bundle to the winding ring anchor bracket loop, welded to the stator with four spiral half-width overlaps, eight layers off tape, with enough tension to hold the coil bundle in position away from the stator bore. The complete anchorage should be 50mm wide.
2) Ensure that the tapes are thoroughly dry before applying the adhesive.
c) Tie off the band using a square (reef) knot positioned over the top outer coils of the bundle, as shown. The knot should be located between two cables rather than pressing on top of a cable.
4) The adhesive should completely cover the knot.
c) Alternatively use Ren Epoxy RP106/ H953.
3) Mix and apply the adhesive in accordance with the manufacturer's instructions. Curing time of the adhesive is 3 to 6 hours.
5) Check adhesive does not have jagged edges by smoothing with finger after dipping finger in water.
NOTE: The knot must be tied on part of the tape between the coils and the anchorage bracket
6) Check that the adhesive has properly hardened on all knots before proceeding to further operations.
d) Cut the tape ends 25mm from the knot and seal with epoxy resin type adhesive as described in Para. 7.4.9.6
7.25
SECTION 7 MAINTENANCE
2) Clean up the studs, and using a liquid dye penetrant and/or magnetic particle examination, examine for surface cracks, particularly in the stud threads and thread run out areas. NOTE: If there has been a history of leakage in service from the joints and/or previous recorded damage, remove and inspect at least 10% of each flange stud.
3) Identify any corrosive deposits that may be present, i.e. pitted areas etc., and if corrosion is evident, consider its stress corrosion influences. If any stud condition raises doubts as to the stud's serviceability, renew all the studs in the flange. 4) If necessary renew the studs as described in para. 7.5.2 7.4.10.3 Studs on Extended Circulator Service Life
If at the end of the circulator nominal service life, or as otherwise defined, an extension of circulating pump life is proposed, it is recommended that all studs should be renewed. However, should a request be made for an extension to the life of the existing studs, then the following points must be satisfied:-
Fi ure 7.21 Knot Sealin
1) The general condition and surface integrity of the studs must be satisfactory.
7.4.10 Main Flange Stud Inspection
Stud inspection must be carried out in accordance with the inspection cycles indicated below. 7.4.10.1 Stud Inspection Breakdown
at
each
2) There should be adequate residual fatigue life in the studs for the extended life proposed; this can be obtained by suitable fatigue tests carried out on a minimum of three studs selected at random from the pump case/motor case joint.
Flange
Whenever either the pump case/motor case or the motor case/motor cover flange joint is broken, the exposed portion of all the flange studs must be thoroughly inspected visually for indications of damage or corrosion, mainly in the form of pitting and cracks etc. Pitted or cracked studs must be renewed Para 7.5.2.
7.4.11 Repairs to Windings
Always consult Hayward 'Tyler if any doubts exist when repairing windings or making new joints. 7.4.11.1 Rewinding the Motor
Contact Hayward Tyler for assistance should major faults develop which necessitate a complete rewind of the motor.
7.4.10.2 Stud inspection at Pump Overhaul
At each convenient circulator overhaul period, approximately 4 - 5 years, a percentage of the studs must be given a nondestructive examination, as follows: 1) Remove two random studs from the Pump Case/Motor joint and any one stud from the motor-case/motor-cover joint.
7.26
SECTION 7 MAINTENANCE
3) Apply high temperature anti-seize compound or silicone grease to the casing end of the stud.
7.5 ASSEMBLY NOTES NOTE: In the event of new components being required refer to the 'Parts List' on Sectional Arrangement Drawing (Page 7.43) and quote the circulator Serial No.- stamped on the motor nameplate - in all correspondence with Hayward Tyler.
4) Assemble the stud as follows: a) Screw the stud into the case dimension ‘L’ measures 255 mm
until
b) Maintain the ends of the studs on a common plane to adjacent studs within 2 mm, this is essential to prevent fouling of the Hydraulic Stud Tensioner on the studs either side of the stud being tensioned.
7.5.1 General
1) Ensure that all the parts are free from grease and oil.
NOTE: When fitting an individual stud to an assembled unit, screw the stud in until its protruded end is on the same plane as adjacent studs.
2) Clean all the stud and screw holes. Inspect for and remove any burrs. 3) Check for full and free movement of bolts and screws by threading them by hand into their respective mating component prior to assembly.
5) When initially fitting the nut, prevent the stud from turning and ensure the 255 mm protrusion dimension is maintained.
4) Torque wrenches must be calibrated before use. 5) Tightening must be progressive and in a diametrically opposed sequence culminating at the required setting. CAUTION: Ensure that the torque is applied about the axis of the screw by holding the socket and wrench square to the screw head.
6) Threads inside the motor and pump cases must only be lubricated with glycol or glycerine. 7) External threads e.g. pump case and motor cover studs are to be lubricated with silicone grease. 8) Socket head cap screws must be punch locked, unless lock washers or spring washers are used. 9) Always use new spring / lock washers, as applicable. 7.5.2 Assembly of Main Flange Studs
Renew damaged or corroded studs, with reference to Fig. 7/22 and in accordance with the following instructions. 1) Thoroughly clean the threads in the case with a suitable solvent and/or by wire brushing. Remove any very hard encrustation in the threads by running down a tap but this should be used only as a last resort. 2) Check the replacement studs for damage to the threads or protective coating during transit. Renovate or reject damaged studs as necessary.
Fi ure 7/22 Assembl of Flan e Studs
7.27
SECTION 7 MAINTENANCE
7.5.3 Wire Locking
Hexagon headed bolts and screws must be wirelocked in groups of three, (Fig. 7/23, details A, B & C), in accordance with the following instructions:1) Bend a 460mm length of wire into two equal lengths and insert one leg through the bolt head hole, as shown in detail A. 2) Using the wire twister tool, twist the wires together at the rate of between 6 and 12 turns to 25mm, ensuring that no undue strain occurs. Bring the twist to within 3mm, of the next bolt head, and with the wire held taut, insert one leg of the wire into the head and pass the other wire around the hexagon, as shown in detail B. Press the outside leg of the wire close to the bolt-head and twist the wire as described. 3) After threading the wire through the third bolt-head, twist the two legs of the wire together for a further 25mm. Cut off the excess and bend the tail around the bolt head, as shown in detail C.
1.
Open the jaws of the pliers by squeezing the handles together and moving perforated slider, at the centre of the pliers, forward, to release the lock hook.
2.
Grip both legs of the wire in the pliers’ jaws. Squeeze the plier handles together and pull the perforated slider rearwards to lock pliers by the hook lock.
3.
Twist the locking wire by pulling the twist knob and twist rod out of the pliers, letting the pliers spin free as shown.
4.
Return the twist rod by holding the pliers steady with one hand and pushing the flat of the other hand against the end of the knob.
5.
Repeat twisting cycles as necessary.
Fi ure 7/23 Wire Lockin
7.28
SECTION 7 MAINTENANCE
d) Position the securing rings, on the housings and tilting pads. Check that the pads are free to pivot. Secure the ring with the screws using lock washers as applicable.
7.6 ASSEMBLY Assemble the components to the motor as follows: -
NOTE: The tilting pads are numbered to identify each set and marked with an arrow to indicate the rotational direction.
7.6.1 Stator Shell and Journal Bearings
1) Fit the journal bearings (Fig. 7/24) as follows:-
e) Check that the pads are free to tilt slightly when the trailing edge is depressed. If there is no movement, remove the pads and grind the spacers on the side to allow a tilting action.
a) Fit the two bearing anti-rotational stop pegs in each bearing ring. b) Fit the bearing rings in the bearing housings.
f) Torque tighten the screws.
c) Assemble the tilting pads in the correct sequence, against the bearing ring housing.
Fi ure 7/24 Journal bearin - Assembl
7.29
SECTION 7 MAINTENANCE
3) Prepare the stator shell, complete with pumpend bearing housing, for insertion in the motor case as follows: -
2) Install the pump-end bearing housing to the stator shell, (Fig. 7/25) as follows: a) Lay the stator shell horizontally and wedge firmly.
NOTE: The cover-end bearing housing and the reverse thrust housing are temporarily fitted at this stage to provide the means of lifting the stator assembly into the motor case.
b) Clean the mating surfaces of the stator shell ends and the bearing housing. c) If previously removed, insert the housing lock rings in their respective end of the stator shell observing the matching up marks for screws.
a) Fit an eyebolt to the cover-end bearing housing periphery. Sling and lift the bearing housing to the stator shell.
d) Fit the split rings in their grooves in the stator shell.
b) Ensure that the terminals and cables are stowed in the stator bore and temporarily fit the cover-end bearing housing, securing with the socket-headed cap screws. Tighten the screws.
e) Pull the bearing housing lock rings up to the split rings, and secure the lock rings to the stator shell with socket-headed cap screws. f) Fit an eyebolt to the periphery of the pump end bearing housing. Attach a shackle and sling and lift the bearing housing to the stator end opposite to the end with the cable leads.
c) Temporarily fit the reverse thrust housing, securing with the socket-headed cap screws. Tighten the screws. d) Using chalk marks, transfer the radial location of the anti-rotation peg from the pump-end bearing housing along the stator shell to the cover-end bearing housing.
g) Align the slot in the pump-end bearing housing with the anti-rotation peg match marks on the stator shell, and locate the housing in the shell.
NOTE: The anti-rotation peg slot should line up with the centre gland hole in the stator shell.
h) Fit the socket-headed cap screws and lock washers to secure the pump-end bearing housing to the stator shell and torque tighten.
e) Ensure that the motor case is in a true vertical position, with the pump end downwards, and stable.
Fi ure 7/25 Stator Assembl
7.30
SECTION 7 MAINTENANCE
4) Install the stator assembly in the motor case (Fig. 7/11) as follows: CAUTION Do not damage the chamfered register on the pump end bearing housing when handling the stator assembly. Before leaning over the motor ensure that you remove headgear and any other objects liable to drop into the motor case.
a) Attach eyebolts and lifting tackle to the reverse thrust housing. b) Carefully raise t he stator assembly over the motor case. Align the chalk marks made in operation 3(c) and lower it vertically into the motor case. c) Raise the stator assembly approximately 3mm and try and turn the stator in the direction the starting torque is applied, against the anti-rotation stop peg. If the peg stops the stator from turning, lower the stator back onto its register. d) Remove the reverse thrust housing and cover-end bearing housing from the stator and withdraw the cable leads from the stator bore. (The removal of the cover-end bearing housing is the reversal of its temporary fitting.). 7.6.2 Journal Sleeves (Fig. 7/26)
1) If a journal sleeve has been removed, fit a new sleeve as follows: a) Clean the journal seat and the bore of the journal sleeve. b) Re-fit the sleeve key and ensure that the journal locking screw is below the shaft surface.
Fi ure 7/26 Journal Sleeves
c) Heat the new sleeve in water at a temperature of 80°C for 15 minutes then quickly slide the sleeve into position on the shaft, tapping it home with a soft faced hammer.
7.6.3 Rotor Assembly (Fig 7/9)
1) Attach an eyebolt, shackle and sling, to the thrust end of rotor assembly.
d) To secure and lock the sleeve after it has cooled, unscrew the locking screw.
2) Ensure that the winding cable leads do not foul the stator bore.
CAUTION: Too much force applied to the locking screw could result in a damaged sleeve.
3) Carefully raise the rotor assembly vertically over the stator bore. Lower into the stator, resting the shaft at the impeller end in its approximate final position on a wooden block supported by a screw or hydraulic jack.
e) Check the bearing clearances as detailed in Para. 7.4.1.
4) Remove the lifting tackle but leave the eyebolt fitted.
7.31
SECTION 7 MAINTENANCE
6) Fit new 'O' rings and back up rings in the inner casing recesses. Make sure that the 'O' ring is below the back-up ring, i.e. nearest the motor. Sparingly coat the ‘O’ rings and backup rings with silicone grease.
7.6.4 Terminal Glands (Fig 7/27) CAUTION: Always fit new ‘O’-rings and back-up rings whenever assembling glands.
1) Observing the colour identification, pass the gland moulding complete with back-up sleeve and two belleville washers, through the hole in the motor casing
7) Carefully slide the complete assembly into the motor case, until firmly seated on the support ring, belleville washers and back-up sleeve. NOTE: If the rings are improperly fitted, considerable pressure will be necessary to force the inner casing into the motor case and either the back-up rings or 'O'-rings will be damaged. Also never hammer the end of the terminal stem if the assembly is a tight fit in the inner casing.
2) Clean all components, particularly the 'O'-ring recesses. 3) Apply a light coating of non-conductive silicone grease to the gland moulding and white insulating sleeve. 4) Fit a new ‘O’ ring in the inner casing neck and slide the inner casing over the insulating sleeve and gland moulding, until the gland moulding is fully located inside the inner casing.
8) Fit the gland nut and tighten. 100Nm should be sufficient.
A torque of
9) Ensure that there are no tight bends in the cable and that the cable protective sleeves are correctly positioned. Check the lead cable binding is in good order and keep the lead cables well away from the stator bore
5) Fit the 'C' shaped support ring on the lead cable beneath the Belleville washers as indicated.
Figure 7/27 Terminal Gland - Assembly
7.32
SECTION 7 MAINTENANCE 7.6.5 Cover End Bearing Assembly (Fig. 7/28) NOTE: Make sure that the screw holes in the stator lock ring do not line up with any of the bearing housing screws.
1) a) Fit a new 'O' ring to the periphery of the cover-end bearing housing. b) Using the lifting eyebolts, hoist the bearing housing to just above the motor case and protruding rotor shaft.
5) Using the hexagon-headed screws, draw the lock ring up to and over the split ring. Torque the screws and wire lock in groups of three.
2) Re-fit the cover-end bearing housing using guide rods and observing the correct location match marks. Make sure that the housing seats evenly all round.
6) Assemble the thrust bearings, as follows: a) With the thrust seat standing edge-wise, fit the thrust pads, in their correct sequence on the seat with the thrust pad stops and the split pins.
3) Re-fit the socket-headed cap screws and lock washers and torque tighten.
CAUTION: Pads are supplied as sets and must not be mixed.
4) Position the stator lock ring in the motor case and fit the split ring.
Fi ure 7/28B Cover End Bearin Assembl Fi ure 7/28A Cover End Bearin Assembl
7.33
SECTION 7 MAINTENANCE
b) Ensure that the thrust pads tilt freely to form a liquid wedge with the thrust disc, with the point of the wedge in the direction of rotation. c) Centre the thrust seat, Fig.7/28 detail B, complete with the thrust pads, on the cover end bearing housing. Assemble with the socket-headed cap screws and spring washers. Torque the screws. NOTE: If the thrust pads reclaimed by grinding are fitted, a shim, the thickness of the metal removed, must be fitted between the thrust seat and bearing housing. This is to ensure that the rotor laminations remain centralised with the stator laminations.
7) Fit the thrust disc key to the rotor shaft. CAUTION: Before fitting the thrust disc ensure that the thrust disc and thrust pad contacting surfaces are scrupulously clean.
8) Fit the thrust disc as follows: a) Extend the jack beneath the rotor assembly to raise the rotor higher than normal. b) Lower the thrust disc on to the shaft and key. Once the disc is located on the shaft, lower it smartly to ensure that it seats firmly against the shaft. c) Fit the thrust disc spacer washer. Fi ure 7/28C Cover End Bearin Assembl
d) Fit the thrust nut. Hand tighten the thrust nut until the thrust disc has no movement. e) Lower the jack until the thrust disc is seating positively on the thrust pads. f) Tighten the thrust nut and fit the split pin as follows:-
9) Fit the reverse thrust seat housing (Fig 7/28C) as follows: -
i) Using the castellated wrench, supplied in the tool kit, and by un-assisted manual strength only, tighten the nut as far as possible.
a) Ensure that the reverse thrust components are scrupulously clean. b) Fit the composite reverse thrust wear ring to the reverse thrust housing, the radial grooves outwards, using the six socketheaded cap screws and the Philidas nuts.
ii) Remove the wrench and radially match mark the top of the shaft and nut. iii) Re-fit the wrench and ‘slog’ tighten the nut until one of the castellations (cutouts) in the nut lines up with the split-pin hole in the shaft.
CAUTION: Avoid damaging the composite ring when tightening the screws.
c) Fit the assembled reverse thrust housing using the socket-headed cap screws and spring washers.
iv) Check that the nut has turned at least 3mm from the match marked position. If this tightness is not obtained, re-slog the nut up until the next hole lines up (maximum 12mm further).
d) Torque tighten the screws. 10) Check the rotor end float, as detailed in 7.6.6., before completing the reverse thrust housing assembly.
v) Fit the split pin and splay the legs to wrap around the nut.
7.34
SECTION 7 MAINTENANCE
Fi ure 7/28 End Float Check T
7.35
ical Method
SECTION 7 MAINTENANCE 7.6.6 Checking End Float (Fig. 7/29) 7.6.6.3 End float adjustment
There are two methods of checking the rotor end float, a recommended method using a dial indicator or if such an instrument is not available, an alternative method with a straightedge and feeler gauges.
1) Below limits: If the dimension obtained is below the specified limit (Section 1) remove the reverse thrust plate and either: a) Method 1
7.6.6.1 Recommended method - Dial Indicator
Make a steel shim to fit between the reverse thrust plate and the cover-end bearing housing, the shim thickness to bring the endfloat within limits.
1) Make sure that the thrust disc is seating on the thrust pads. 2) Set up a dial indicator as follows:
Or
a) Set up the dial indicator on the top of the reverse thrust housing, using a magnetic block to hold the indicator to the housing.
b) Method 2 Lightly machine the face of the reverse thrust housing where it makes contact with the reverse wear ring. The amount machined is determined by the difference between actual measurement and the required end-float.
b) Set the indicator to record any vertical movement of the rotor using a suitable spacer if necessary. c) Set the indicator dial to zero. 3) Using the jack beneath the rotor, raise the rotor, complete with thrust disc, until the thrust disc is positively in contact with the underside of the reverse thrust plate.
2) Above limit: if the end-float exceeds the specified limit, remove the reverse thrust housing and either:-
4) Check the dial indicator reading: the reading is the amount of end-float. The end-float must conform to that specified in Section 1 Technical Data
i) Remove the reverse thrust wear ring from the reverse thrust housing.
a) Method 1
ii) Make a steel shim of a thickness to bring the excess end float within limit, and fit between the reverse thrust wear ring and the housing.
5) Adjust the end float, if necessary, as described in operation 3 - End Float Adjustment.
b) Method 2
6) When the end float is satisfactory, fit all the twelve socket-headed cap screws and lock washers in the reverse thrust housing. Torque tighten the screws.
i) Lightly machine the outer face of the reverse thrust housing where it contacts the cover-end bearing housing. ii) Re-fit the reverse thrust wear ring with the six socket-headed cap screws and Philidas. Torque tighten the screws.
7.6.6.2 Alternative method - Feeler Gauges
1) Check that the rotor assembly is supported by the thrust pads.
3) Fit the reverse thrust housing finally to the bearing housing with the twelve socket headed screws and lock washers. Torque tighten the screws.
2) Place a straight edge across the reverse thrust seat housing. Using a suitable spacer resting on the rotor and long enough to reach to within 10mm. of the underside of the straight edge, measure with feeler gauges and record the exact clearance between, and straight edge. Dimension Y.
7.6.7 Motor Cover Filter – Assembly (Fig 7/30)
1) Fit the filter assembly as follows:a) Offer the filter assembly to the reverse thrust housing.
3) Using the jack beneath the rotor, raise the rotor until the thrust disc is in positive contact with the underside of the reverse thrust pads.
b) Secure with the hexagon-head screws and lock washers and torque tighten. 2) Fit the motor cover as follows:-
4) Measure and record the exact clearance between spacer and straight edge, dimension X. The difference between Dimension X and Y is the end float. See Section 1, Technical Data, for limits.
a) Ensure that the scrupulously clean.
flange
faces
are
b) Position a new flexitallic spiral wound gasket in the motor case recess. c) Using lifting tackle, lower the cover into position on the motor case flange, aligning the case/cover match marks.
NOTE: As a further alternative, a straight edge and depth gauge can be used.
7.36
SECTION 7 MAINTENANCE
3) Using two cranes and slings, lift the motor from the building stand and lower the motor into a horizontal position, terminal stems uppermost (see Fig.7/5). Chock to prevent movement.
NOTE: If the cover does not seat correctly, raise it again and check that the gasket has not been damaged.
d) Coat the threads of the studs and nuts with anti-seize compound or silicone grease. Fit and hand tighten the nuts.
4) Blank-off all the motor case openings until the unit is installed.
e) Tension the studs as detailed in Section 8.
Figure 7/30 Motor Cover and Filter Assembly
7.37
SECTION 7 MAINTENANCE
Fi ure 7/31 Terminal Box
7.38
SECTION 7 MAINTENANCE
Figure 7/32 Terminal Link Insulation
7.39
SECTION 7 MAINTENANCE 7.6.8 Terminal Boxes (Fig. 7/31, 32, 33)
Fit the terminal boxes as follows: 1) Ensure that the neoprene gasket is located on the terminal box support. 2) Using the lifting tackle on the terminal box eyebolt hoist the terminal box onto the terminal box support and secure with nuts and washers. 3) Fit each terminal link as follows: a) Connect the terminal link clamp connector to the terminal gland stem with the socket headed cap screws and nuts. 4) Insulate the terminal connecting links with reference to Fig. 7/32 as follows: a) Cover the complete length of the connecting link including the terminal clamp connector with 3M No. 70 silicone thermosetting tape to a minimum thickness of 3mm in three staggered layers. b) Slide a length of heat shrink tubing over the insulated section and, as far onto the clamp connector as possible removing all wrinkles. c) Using a hot air gun or propane gas torch operating at a temperature of 150°C, heat the tubing and working outwards from the centre, heat shrink until a tight fit over the taped area. 5) Re-fit the respective terminal link ends to the terminal block, and secure with washers and nuts. 6) Check that the bursting discs are intact. The details of the bursting disc assembly are shown as an exploded view in Fig 7/33. 7) Re-new the cover gasket. 8) Fit the terminal box cover and secure with nuts and washers to protect the terminal stems until the main supply cables are fitted.
Fi ure 7/33 Burstin Disc Details
9) Temporarily fit and secure the terminal box cover until the main supply cables are fitted.
7.40
SECTION 7 MAINTENANCE
Figure 7/34 Impeller Setting
7.41
SECTION 7 MAINTENANCE 7.6.9 Baffle Wear Ring (Fig.7/34)
6) Draw the impeller and rotor assembly forwards until the thrust disc rests upon the thrust pads.
If the baffle wear ring has been removed, re-fit as follows: 1) Place the ring on the integral baffle and attach with the socket-headed cap screws and lock washers.
7) Measure the dimension between the top of the impeller and the pump/motor case flange (Dimension ‘Z’ shown in Fig. 7/34). Adjust the thickness of the impeller washer as necessary, to obtain the dimension given in Section 1.4 - Technical Data.
2) Torque tighten the screws. 7.6.10 Main Impeller (Fig. 7/34)
Fit the impeller as follows: -
8) Re-new the locking screw, torque tighten and punch lock.
1) Remove the protective impeller nut and fit the impeller key.
9) If the unit is to be stored, cover the impeller with the transit canister and the flanges with the flange covers. Slowly fill the motor with inhibitor through the inhibitor filling valve.
2) Fit the impeller washer with the internal chamfer towards the shaft shoulder. 3) Coat the threads of the left-hand threaded impeller screw with silicone grease, then re-fit the impeller and the impeller nut
7.6.11 Heat Exchanger
Ensure that the heat exchanger is serviceable before refitting as described Para. 4.3 – Section 4
4) Check that the gap between the key and the top of the impeller hub does not exceed 0.25mm. 5) Using the special impeller nut spanner and tommy bar, supplied in the tool kit, and a lead-faced hammer, tighten the impeller nut.
7.7 RE-INSTALLATION OF MOTOR The re-installation of the motor assembly to the pump case is carried out in accordance with the installation procedure described in Section 4, para. 4.3
NOTE: The impeller nut has a left-handed thread. Do not use any leverage in the water passages of the impeller to oppose force exerted by the spanner, the weight of the rotor will oppose rotation if the spanner is given a few heavy blows with a lead-faced hammer.
7.42
SECTION 7 MAINTENANCE
PARTS LIST – SECTIONAL ARRANGEMENT ITEM NO.
PART NO.
DESCRIPTION
QTY.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56
42789/1003 16884M16/50 42789/1010 42789/1202 42789/1401 42789/1204 42789/2030 16884M12/35 42577/212 42488/433 42789/1801 42789/1227 42789/1806 42401/111 16884M12/60 42577/212 42789/1704 42789/2108 42789/2111 16884M10/55 42577/210 42789/1805 42789/2101 42789/2110 42789/2104 42789/2105 42789/1705 16801M10/55 42577/210 16884M6/12 42789/1701 42789/1601 42789/1605 167WBDGJ62M0 42789/1603 42789/1501 16884M12/120 17207M12 42789/003 42488/431 42789/2028 42789/2029 16884M6/45 16526M6 42789/1242 42789/1243 42789/1205 42789/028 167WBCNN10M0 42789/2502 42789/2501 42789/1901 16201M10/45 42577/210 42401/112 16884M8/25
PUMP CASE SKT HEAD CAP SCREW CASE WEAR RING IMPELLER NUT IMPELLER IMPELLER KEY BAFFLE WEAR RING SKT HEAD CAP SCREW NORDLOCK WASHER GASKET - PUMP/MOTOR FLANGE PUMP END BEARING HOUSING JOURNAL SLEEVE JOURNAL TILTING PAD ASSEMBLY HEAT EXCHANGER SPOOL PIECE SKT HEAD CAP SCREW NORDLOCK WASHER BEARING RING SPLIT RING – STATOR SHELL BEARING HOUSING LOCK RING SKT HEAD CAP SCREW NORDLOCK WASHER SECURING RING- PUMP END STATOR SHELL STATOR KEY STATOR LAMINATION STATOR END PLATE SECURING RING - COVER END HEX HD SCREW NORDLOCK WASHER SKT HEAD CAP SCREW COVER END BEARING HOUSING THRUST SEAT THRUST PAD STOP SPLIT PIN THRUST PAD THRUST DISC SKT HEAD CAP SCREW SINGLE COIL SPRING WASHER TERMINAL BOX ASSEMBLY FLEXITALLIC GASKET – MOTOR COVER STUD – MOTOR CASE/MOTOR COVER NUT – MOTOR CASE/MOTOR COVER SKT HEAD CAP SCREW PHILIDAS NUT THRUST NUT SPACER THRUST NUT THRUST DISC KEY FILTER ASSEMBLY SPLIT PIN REVERSE THRUST PLATE REVERSE THRUST HOUSING MOTOR COVER HEX HEAD SCREW NORDLOCK WASHER FILL & DRAIN SPOOL PIECE SKT HEAD CAP SCREW
1 1 1 1 1 1 1 6 6 PR 1 1 2 2 SETS 2 12 12 PR 2 3 2 8 8 PR 1 1 1 805 MM 2 1 8 8 PR 6 1 1 12 12 12 1 12 12 3 1 16 16 6 6 1 1 1 1 1 1 1 1 6 6 PR 1 6
7.43
SECTION 7 MAINTENANCE 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85
17207M8 42789/2910 169XYNFB 42789/2903 42789/2904 16884M12/90 42577/212 42789/1711 40744/123 42789/013 42789/2125 42789/2001 42401/112 16884M6/12 36810/185 42789/1208 42789/1710 42789/1209 42789/2017 42789/2016 42789/2015 42789/2016 42789/1018 42789/1018 42789/1201 16884M10/55 42577/210 38882/102 42789/1405
SINGLE COIL SPRING WASHER STATOR LOCKING SCREW LOCKING WIRE SPLIT RING – STATOR LOCK RING STATOR LOCK RING SKT HEAD CAP SCREW NORDLOCK WASHER ‘O’ RING – BEARING HOUSING WINDING SUPPORT BRACKET ROTOR ASSEMBLY WINDING CABLE MOTOR CASE PRESSURE GAUGE SPOOL PIECE SKT HEAD CAP SCREW LOCKING PIECE - SPLIT RING JOURNAL SLEEVE KEY ANTI-ROTATION PIN JOURNAL LOCKING SCREW ANTI-ROTATION PEG THERMOMETER POCKET THERMOWELL TEMPERATURE SWITCH POCKET NUT – PUMP/MOTOR CASE STUD – PUMP/MOTOR CASE IMPELLER WASHER SKT HEAD CAP SCREW NORDLOCK WASHER GRUBSCREW IMPELLER WEAR RING
6 18 A:R 1 1 12 12 PR 1 6 1 3 1 1 1 1 2 4 2 1 1 2 2 18 18 1 6 6 PR 3 1
PARTS NOT ILLUSTRATED ITEM NO
DESCRIPTION
QUANTITY
42554/035
FILLING VALVE ASSEMBLY (TRANSIT ONLY)
1
INSTRUMENTS ITEM NO
DESCRIPTION
QUANTITY
42401/156 42401/157 42401/201 42646/203 42646/203 42401/204 42401/205 42401/206 42401/207 42478/117
JUNCTION BOX – TEMPERATURE SWITCH JUNCTION BOX – THERMOCOUPLES FLOW METER THERMOCOUPLE – PUMP SUCTION MANIFOLD THERMOCOUPLE – PUMP CASE TEMPERATURE SWITCH THERMOMETER THERMOCOUPLE – MOTOR CAVITY PRESSURE GAUGE – MOTOR CAVITY DIFFERENTIAL PRESSURE TRANSMITTER WITH MANIFOLD
1 1 1 1 1 2 1 1 1 2
7.44
SECTION 7 MAINTENANCE
PARTS LIST - TERMINAL GLAND
TERMINAL GLAND ASSEMBLY - 3 OFF - EACH COMPRISING: PART NO.
DESCRIPTION
QTY.
42789/2320 42789/2314 42789/2315 42789/2331 42789/2333 42789/2332 42789/2313 42789/2312 SP42789/023
THREADED BUSH (GLAND NUT) INNER CASING SUPPORT RING ‘O’ RING (CABLE GLAND) ‘O’ RING (STEM) SPIRAL BACK-UP RING BELLEVILLE WASHER BACK UP SLEEVE GLAND MOULDING AND CABLE ASSEMBLY
1 1 1 2 1 2 2 1 1
PARTS LIST - TERMINAL BOX
ITEM No
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
PART NO.
DESCRIPTION
QTY .
SP42789/027
TERMINAL BOX ASSEMBLY- EACH COMPRISING
3
42789/2705 16012M10/25 17207M10 16501M10 SP42789/023 16220M12 42789/2701 42789/2708 16012M10/25 17207M10 16501M10 42789/2707 16220M12 42789/2732 42715/2721 16884M6/50 42789/2723 42789/2713 42789/2711 16012M10/35 17207M10 16501M10 42715/2740 42789/2741 42789/2720 42789/2719 16884M12/55 42789/2717
GASKET-TERMINAL BOX SUPPORT STUD- TERMINAL BOX SUPPORT SHAKEPROOF WASHER - TERMINAL BOX SUPPORT NUT- TERMINAL BOX SUPPORT TERMINAL GLAND ASSEMBLY EYEBOLT TERMINAL BOX FLASHPLATE ASSEMBLY GASKET - TERMINAL BOX COVER STUD- TERMINAL BOX COVER WASHER- TERMINAL BOX COVER NUT- TERMINAL BOX COVER TERMINAL BOX COVER EYEBOLT TERMINAL LINK ASSEMBLY TUBULAR LUG SOCKET SKT HEAD CAP SCREW – BURSTING DISC HOUSING BURSTING DISC PANEL DESSICATOR GASKET – GLAND PLATE STUD - CABLE ENTRY PLATE WASHER - CABLE ENTRY PLATE NUT - CABLE ENTRY PLATE CABLE GLAND GLAND PLATE NUT – TERMINAL SCREW WASHER – TERMINAL SCREW EPOXY RESIN SKT HEAD CAP SCREW – TERMINAL BLOCK TERMINAL BLOCK ASSEMBLY
1 12 12 12 1 1 1 1 1 26 26 26 1 1 3 1 8 2 1 1 4 4 4 1 1 10 8 2 1
7.45
SECTION 7 MAINTENANCE
SPARES PARTS –COMMISSIONING
PART NO.
DESCRIPTION
QTY *
42789/2333 42789/2331 42789/2332 42488/431 42488/433 39930/207
SMALL ‘O’ RING - TERMINAL GLAND LARGE ‘O’ RING - TERMINAL GLAND BACK-UP RING - TERMINAL GLAND GASKET - MOTOR COVER GASKET - PUMP / MOTOR GASKET – FILLING VALVE (HP)
3 6 6 1 1 1
* QUANTITIES ARE PER UNIT
7.46
SECTION 7 MAINTENANCE
Figure 7/35 General Arrangement
7.47
SECTION 7 MAINTENANCE
Fi . 7/36 Sectional Arran ement
7.48
SECTION 7 MAINTENANCE
Fig. 7/37 Terminal Box Arrangement
7.49
SECTION 7 MAINTENANCE
Fi . 7/38 Tool Kit List
7.50
SECTION 8 STUD TENSIONING EQUIPMENT
CONTENTS
PARAGRAPH
PAGE
8.1
INTRODUCTION
8.2
8.2
APPLICATION
8.2
8.3
DESCRIPTION
8.2
8.4
ASSEMBLING THE STUD TENSIONER
8.3
8.5
REPLENISHING THE PUMP TANK
8.6
8.6
INDEXING
8.6
8.7
SAFETY PROCEDURES
8.7
8.8
TIGHTENING THE FLANGE NUTS
8.7
8.9
RELEASING FLANGE NUTS
8.8
PARTS LIST
8.11
ILLUSTRATIONS
FIGURE 8/1
HYDRAULIC STUD TENSIONING EQUIPMENT
8.1
FIGURE 8/2
SINGLE PISTON STUD TENSIONER (EXPLODED VIEW)
8.4
FIGURE 8/3
SINGLE PISTON STUD TENSIONER (GENERAL ARRANGEMENT)
8.5
FIGURE 8/4
QUICK RELEASE COUPLING
8.6
FIGURE 8/5
NUT TIGHTENING SEQUENCE
8.9
NUT TIGHTENING SEQUENCE (CONTINUED)
8.10
8.0
SECTION 8 STUD TENSIONING EQUIPMENT
Figure 8/1 Hydraulic Stud Tensioning Equipment
8.1
SECTION 8 STUD TENSIONING EQUIPMENT
8.3.2 Hand Pump
8.1 INTRODUCTION
The stud tensioner equipment hydraulic pump is a hand operated, dual piston, high pressure unit. Initially, both low and high pressure flow is applied at each pump handle stroke until the tensioning head starts to take load, when the high pressure application continues and the low pressure is diverted back to the oil reservoir. Re-setting of the low and high pressure takes place automatically allowing the pump to operate with maximum efficiency at all times. Pressure limiting valves trip when the pressure exceeds the pump capacity.
All items mentioned herein relate to the M56 Stud Tensioner Equipment supplied as a comprehensive kit. This must be used ONLY in conjunction with the circulator manual for the equipment supplied for the specific contract.
8.2 APPLICATION The physical dimensions of the pump case/motor case joint and the motor case/cover joint prevent adequate pressure sealing by hand-tightened nuts. For these applications, hydraulically operated stud tensioner heads are supplied with each contract. The tensioner heads stretch the studs and the nuts are then tightened down by hand. When the tension on the stud is released, the load is transferred to the nut to give the required tightness.
The pump body contains the oil reservoir, incorporating an oil filter plug and oil pressure return valve for variable pressure release, the pump handle, gauge and quick release high pressure hoses complete the assembly. All the pump components are easy to dismantle for servicing.
When working on a circulator flange joint, all the heads are employed simultaneously, each being diametrically opposed. The heads are positioned on the studs in a prescribed sequence, and are pressurised to specified limit in accordance with each of five consecutive stud tensioning programmes. As the studs are progressively tensioned, the mating flanges are drawn together, so allowing the circulator flange nuts to be tightened or released.
8.3.3 Stud Tensioner Heads
The stud tensioner heads each comprise a bridge that fits over the stud and stud nut to seat on the flange and is retained by the bridge retainer. A tensioner body incorporating a seal, sits on the bridge and is held in position by the threaded insert, screwed on the stud. The head is hydraulically pressurised via a quick release coupling and high pressure hose.
8.3 DESCRIPTION (FIG. 8/1) The Hydraulic Stud Tensioner Equipment comprises three principal components: -
Three of the four heads have two connectors fitted. The fourth head has one connector and one blanking plug. The fourth head is always the last in line in the system, the other heads are interconnected.
1) Tensioner head assembly, including the bridge, tensioner body and piston and threaded insert (see Fig. 8/3). 2) Hand-pump - including oil reservoir.
8.3.4 Operation
3) High Pressure Couplings, hoses and pressure gauge.
When the hydraulic pressure, in accordance with the stud tensioning program, is applied to the tensioner head, the body reacts against the threaded insert which in turn stretches the stud. While the stud is stretched, the stud nut is hand tightened, using the bar provided in the kit.
Four metal rods are provided in the kit. One end of the rod is used for tightening the threaded inserts when installing the heads. The other end is used for pulling down the flange nuts. Although each Stud Tensioner is operable by one engineer, this practice is not recommended due to weight and environmental criteria.
8.2
SECTION 8 STUD TENSIONING EQUIPMENT
Having hand tightened the stud nut, the hydraulic pressure on the tensioning head piston is gradually released, via the hand pump oil return valve, and the load is transferred to the stud nut to give the required tightness. The threaded inserts are unscrewed from the studs and the heads are transferred to the next studs in the tightening sequence.
NOTE: The bridge base circumference should sit flatly against the surface against which it is being tensioned.
5) Attach each threaded insert into the bolt tensioners by screwing onto the threads protruding above each nut. Screw down the inserts using the tommy bars supplied with the equipment, until contact with the load cells is achieved.
8.4 ASSEMBLING THE STUD TENSIONER (FIG. 8/3)
CAUTION: Body and piston seals will be damaged if the piston protrudes excessively from the tensioner body, observe the yellow maximum extension warning line. (Maximum extension 6mm)
The hand pump and its accessory hoses are normally provided, in the toolbox, already assembled needing only to be connected to the tensioning heads. However for information purposes, the assembly of the stud tensioner kit is as follows: -
NOTE: If the seals need replacing, refer to the operator’s manual provided with the stud tensioning equipment.
1) Remove the hand pump, complete with pressure gauge, high pressure hoses and hose couplings from the hydraulic pump tool box.
6) Connect the end of the high pressure feed hose to the first tensioner head.
Ensure that all studs are scrupulously clean and that their threads are undamaged. Carefully examine that portion of each stud thread protruding beyond the flange nut after fitting. If the studs have been in service for some time, inspect as described in the Circulator Instruction and Maintenance Manual.
7) Fit one of the inter-connecting hoses between the first and second heads. 8) Connect up the second and third heads and finally, using the one remaining hose. Connect the fourth head (i.e. with a blanking plug fitted) to complete the circuit.
When tensioning studs of the circulators which have been in service, inspect all faces of each flange nut. Reject any damaged nuts. (Damaged faces of nuts can be re-ground for subsequent re-use).
9) Check the oil level in the hydraulic hand pump, fill or top-up if necessary. NOTE. The quick release female connectors have a knurled security locking ring in the centre. This must be turned to lock the spring-loaded end of the coupling to eliminate the possibility of an accidental disconnection.
CAUTION: Never lubricate the stud top threads, or those of the threaded insert.
2) Install and hand tighten all flange nuts. Apply silicone grease or high temperature anti-seize compound to the threads and faces of each flange nut
CAUTION: Do not pressurise an un-connected male coupling.
3) Connect the high pressure feed hose via the quick release female connector to the gauge tee on the pump. 4) Assemble the load cell and bridge, over the first set of bolts (diametrically opposed) to be tightened. The bridge window should be positioned so that access to the nut is obtained. It is normal for the bridge window to face radially outwards from the centre of the circular flanged joint.
8.3
SECTION 8 STUD TENSIONING EQUIPMENT
Figure 8/2 Single Piston Stud Tensioner Exploded View
8.4
SECTION 8 STUD TENSIONING EQUIPMENT
Figure 8/3 Single Piston Stud Tensioner General arrangement
8.5
SECTION 8 STUD TENSIONING EQUIPMENT
Fi ure 8/4
uick Release Cou lin
8.6 INDEXING 8.5 REPLENISHING THE PUMP TANK
It is essential that the gasket is uniformly compressed and the studs evenly prestressed. To ensure this, diametrically opposed flange nuts are tightened simultaneously in accordance with a predetermined numbering sequence.
The pump is supplied already filled with oil but after repeated use the oil should be replenished as follows:1) Unscrew the oil filler plug from the top pump tank.
Using any convenient nut as No. 1 and working in a clockwise direction, sequentially mark with chalk on the flange periphery, the appropriate nut tightening sequence. Refer to Fig.8/5 for Nut Tightening Sequences.
2) Replenish the tank from the 5 litre container of hydraulic fluid to the bottom of the level tube.
8.6
SECTION 8 STUD TENSIONING EQUIPMENT
3) Depress the hydraulic piston fully in the tensioner body by: -
8.7 SAFETY PROCEDURES 1) Eye protection and gloves should be worn when working with high pressure hydraulics.
a) Opening the oil return valve on the hydraulic hand pump using the winged control valve screw.
2) Pressurise slowly, do not exceed the maximum working pressure (1500 bar). Gauge pressure should be constantly monitored during pump operation.
b) Fully tightening the threaded inserts using the rod provided. c) Closing the oil return valve on the hydraulic pump.
3) Do not exceed the maximum piston extension 6mm. indicated by a yellow line.
4) The pump, hoses and tensioner heads are pre-filled and system venting should not be necessary. However, should venting of the system be required, loosen the blanking plug from the last head in the circuit and operate the pump until air free fluid emerges from around the plug on completion of venting.
4) Do not leave a pressurised system unattended, release pressure if leaving the working area. 5) Check the equipment a) Ensure that the hoses are undamaged.
5) Using the hydraulic hand pump, obtain a true pressure stipulated for the 1st pass of the 5 passes given in the following table.
b) Check that all hose couplings are serviceable and tight on the hose ends and tensioning heads.
CAUTION; The indicated gauge pressures are true operating pressures. Never exceed maximum working pressure for the head when tensioning, or damage to the tensioner or to the studs may occur.
6) Check equipment is correctly assembled; a) Tensioning head components must be seated squarely within each other and with the motor cover face or motor pump flange. b) The thread engagement between the stud and the threaded insert must be 48 mm minimum. c) Before pressurising, ensure hose connector security by pulling on each locked connection. 7) Do not attempt to use stud tensioner if unsure of the correct assembly and operation of the equipment. 8) Do not attempt any repairs on the system when under pressure.
PASS
LBF/IN.2
BAR
1ST
5000
350
2ND
10000
700
3RD
15000
1050
4TH
21000
1450
5TH
21000
1450
8.8 TIGHTENING FLANGE NUTS 1) Fit the four tensioner bodies complete with threaded inserts onto the studs and screw down on to each bridge. Attach the hydraulic link hoses (See Section 4).
TENSIONING PRESSURE PROGRAM
2) Ensure that the insert is fully depressed within the tensioner body.
8.7
SECTION 8 STUD TENSIONING EQUIPMENT
6) The piston stroke and pressure should be continually monitored so that neither go above the corresponding working pressures. If the maximum piston stroke is reached before working pressure is achieved go straight to procedure (8).
13) When all flange nuts are correctly tightened, the gasket is fully compressed and the nuts pre-stressed. 14) Check at several equi-distant points on the flange periphery that the gap between the faces of the pump case and motor flanges is less than 1.5 mm.
Close the pump stop valve, then pressurise the system to the required pressure, when this is reached stop the pump to hold the pressure.
8.9 RELEASING FLANGE NUTS WARNING: Ensure that the motor is electrically isolated, adequately supported and depressurised, before any nuts are slackened.
7) Check the pressure gauge to ensure the pressure is holding constant. When satisfied that the pressure is stable, use the tommy bars to rotate the nuts, through the access windows, down towards the joint surface. Fit the appropriate rod (bar) to the flange nuts and fully hand tighten. Hand tighten adjacent loose nuts.
1) Fit the tensioner heads to the studs and connect the hoses and hand pump. If one head is used for this operation it must be the head with the blanking plug fitted.
8) Remove the stud tensioner heads by:-
2) Screw down the threaded insert fully, then release it one half (½) turn. Pressurise the system to 1500 bar and unscrew each flange nut one half (½) turn using the appropriate bar. Repeat for every stud on each pass.
a) Screwing in the oil return valve on the pump to release the oil pressure (which transfers the load to the nuts). b) Tightening, then releasing the threaded insert.
3) Should the nuts fail to move, a slow gradual increase in pressure should be made until the nut lifts of the flange face. At this stage, a further increase in pressure is un-necessary and will not assist in freeing a tight nut.
c) Screwing out the oil return valve on the hand pump. d) Removing the threaded complete with body.
insert
e) Removing the bridge. f) Disconnect the hydraulic hoses.
CAUTION: Never exceed the maximum system pressure when removing the nuts.
NOTE: If the required pressure is not reached, return to step 2.
4) If the nuts are still in contact with the flange and cannot be removed with the system at absolute pressure, consult Hayward Tyler for advice.
9) Transfer the stud tensioners to studs numbered 2 in the tightening sequence. Repeat operations 2) to 8). 10) Continue tightening progressively to the numbered sequence until all the nuts are tightened to the 1st pass pressure i.e. nuts 2 in turn then nuts 3 followed by nuts 4, then 5 and so on.
5) Repeat the stud tensioning and nut unscrewing sequences diametrically until all flange nuts are released. 6) After use, thoroughly clean, examine for damage and lubricate each component of the stud tensioner equipment. Wrap all components in suitable water-proof material then store in a clean, dry area in their respective tool boxes.
11) Repeat the tightening sequence round the flange of a 2nd, 3rd, 4th or 5th pass, at the stud tensioning pressure stipulated for the applicable pass. 12) If, on the 5th pass, the flange nuts can be tightened further, additional passes at maximum pressure should be made until no further tightening is possible.
8.8
SECTION 8 STUD TENSIONING EQUIPMENT
Fi ure 8/5 Nut Ti htenin Se uence
8.9
SECTION 8 STUD TENSIONING EQUIPMENT
Figure 8/5 Nut Tightening Sequence (Continued)
8.10