#5 Scope of Work

7/30/2019 #5 Scope of Work

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1. Dismantling of safety valve and its discharge elbow etc and recording of all the settings.

2. Inspection of seat and disc along with the Engineer In charge.

3. After inspection get the clearance for lapping. Ring laps will have to be brought by contractor.

However it will be given by BTPS if available

4. After inspection of each & every part of safety valve by Engineer in charge, the safety valve

spindles to be checked and straightened if bent in CRS.

5. Disc and seat to be lapped to mirror finish.

6. All the settings are to be checked and corrected to the satisfaction of Engineer in charge. All the

safety valves are to be boxed up in presence of Engineer in charge or his representative.

7. All other parts such as discharge elbow and main outlet pipe are to be suitably repaired.

8. All the safety valves are to be set as per the earlier values for their respective operating

pressures. The settings of the valves are to be fine-tuned when the safety valves are checked

by TREVI TEST or by conventional method. (However the Trevi test is excluded from this

package.) If any of the safety valves do not function to the satisfaction of Engineer in charge,

they are to be attended as per instructions of EIC (It may require complete re-servicing).

9. All the flanges gaskets are to be replaced, if any, after all the mating faces are checked for

flatness and when free from dents/ scratches.

10. Where the repair of the safety valve is not possible by lapping/ or other componentreplacement, the safety valve body needs to be replaced. However cutting and welding of thevalve is not in the scope of this package. The new valve has to be serviced as per the aboveprocedure and boxed up.

1. Removal of Actuator ( after the electrical connections are disconnected by C&I dept andafter getting clearance from engineer in charge.)

2. Removal of yoke after dismantling from the valve.3. Dismantling of the valve after marking the components and the dismantling of the bonnet. The

wedge /disc / plug are to be dismantled after marking them for identification.4. Removal of other parts carefully such as stem , stem nut , bonnet, upper and lower cage

in case of control valves.

5. Removal of all the above parts of the valve should be done properly so as to avoid

any damage.

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1. After the inspection by Supervisor /Engineer In charge after necessary cleaning has beendone, the condition of following parts is to be recorded:Body, bonnet, all sealing surfaces- extent of pitting if any, Wedge, globe, stem, yoke, fastenersetc.

2. Check the Valve body seat, Wedge /Disc /Plug for their satellites portion.3. Preparation for DP test of the sealing surfaces . The DP test kits will be provided by BTPS. And

inspection will be done by BTPS4. Check all the different parts for reliability with respect to their function.5. Taking care of above points, in case the valve is to be replaced if any of the major

components are damaged beyond repair / servicing the new valve to be serviced eitherbefore or after the welding as per instruction of Engineer in-charge.

6. Lapping of disc /wedge, body seat with the help of lapping tools using emery paste,lapping to be continued till satisfactory result is attained as per the discretion ofSupervisor / Engineer In charge.

7. After the satisfactory result obtained in lapping, different parts to be checked for theirfitment and get the clearance for box up from supervisor / Engineer in-charge.

The valve is to be boxed up with the bonnet and other parts properly placed in its position

using new self sealing ring, new gasket asbestos/ spiral wound gasket in flanged type valves .The valve stuffing box is to be filled using new gland packing ring / rope as per the availability.After completion of box up of the valve, using the proper lubricant , each valve is to be checkedfor manual / electrical operation. Valve limits for opening & closing to be set in co- ordinationwith C&I division.Hot tightening of all the Valves to be done in co-ordination with Engineer in-charge andoperation department.All the above jobs are to be done to the entire satisfaction of the engineer in charge.

Sl No Valve size Tentative Quantity.Nos

2.1 >10mm but 25mm but < /=50NB 30

2.3 >50mm but 100mm but 250NB 04

The job involves opening the man hole cover for inspection of the internals for any damage. If anycracks are found in the internal components, the same are to be suitably repaired by welding aftergrinding them. The supporting structure if is found damaged/ rusted, the same needs to be repaired bywelding new structural members.

The scope involves cutting the valve from the pipe line by grinder from both ends after suitably lockingthe line for avoiding movement of the lines. New valves are to be shifted to site from the store and

their weld edges are to be rectified if found not suitable for welding. The pipe line ends also need to beprepared to a suitable standard weld joint edge as per the thickness of the pipe. Valve body is to beheld in the line with suitable fixtures. If length of the valve does not match the previous valve, a spoolpiece of suitable length needs to be prepared with suitable weld ends. The valve is to be welded to thelines with proper weld procedure like preheating and control of inter-pass temperature. This alsoincludes suitable rerouting/ modification of pipe lines as per site requirements. The details of varioussizes of valve related pipe joints are as follows.

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Sl No Valve size QuantityNos

4.1 >10mm but 25mm but 50mm but 100mm but < /=250NB 01

4.5 >250mm 01

(a) Supply & Erection and of cup lock type scaffolding system in the first pass

Erection of scaffolding in furnace and else wherever required in the first pass as per the details givenbelow:

a) Ceiling with wooden Planks at bottom Neck portion of the S panelb) Two tier blanking at:

a i) Platen super heater level.b ii) Below lowest burner A elevation (approx. 18 m level)c c) Scaffolding to be erected up to ceiling super heater (Roof) at 50 m elevation.d d) Stairs up to 50 m level in staggered form.e e) Peripheral working platform all around the furnace in front, left, right and rear up to 50 m level

and in rear up to goose neck area at every 2/3 meter height with handrails.

(b) Scaffolding in second pass and horizontal passErection of complete platform using wooden planks below the economiser covering the whole of theeconomiser hoppers. Erect scaffolding with platforms in between and by the sides of PlatenSuperheater, reheater, final Superheater, between steam-cooled wall and final super heater, and

screen tubes to facilitate cleaning, inspection and repair of tubes.

Open all the manholes of pent house and boiler.The ash has to be removed from the following areas by dry cleaning:Pent house, pent house roof above the pent house, dead chamber goose neck, dead chambers

bottom of the boiler, secondary air and flue gas ducts, wind boxes and external platforms allaround the boiler at different elevations.

After the platform are erected, the outer surfaces of the tubes are to cleaned in the following

areas:Water wall from bottom up to ceiling super heater, Platen S.H, Water wall Platen, re-heater panels,Final superheater, screen tubes, steam cooled walls, water washing of LTSH, Economiser tubes, etc.

.Area includes Economiser, LTSH, supply tubes, steam cooled walls, Platen Super Heater, finalsuperheater, Screen tubes, Reheater etc.

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Cutting and removal of damaged tubes and clamps. Fabrication of bends and attachment wherevernecessary as per the instruction of engineer-in-charge. Edge preparation in new and parent material.Welding of tubes as per the instruction of the engineer-in-charge. Rectification of defects if any afterradiography.

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Area includes water wall, water wall platen, water wall screen tubes, bottom header drains, etc.Cutting and removal of damaged tubes and clamps. Fabrication of bends and attachment wherevernecessary as per the instruction of engineer-in-charge. Edge preparation in new and parent material.Welding of tubes as per the instruction of the engineer-in-charge. Rectification of defects if any afterradiography.

The scope includes critical piping hanger/tie rod supports of Main steam, Hot Reheat, Cold Reheat,headers and pipe in pent house and its roof and feed line. Assist the personnel in cold/hot reading.

Identify the damaged hanger supports with the engineer in charge. Make necessary scaffolding. Dothe necessary repairs and minor adjustments, which include replacing support plates/pins/fastenerson the hanger supports. Job includes replacing of pins, welding of support plates, etc.

The scope includes Shifting of the materials such as cassette baffles, tubes, etc from the store

to the site. Lifting of the LTSH panel after cutting the tubes, cleaning of the coils after removingthe cassette baffles. Welding supports/clits of the hanger tubes wherever needed as per theinstruction of engineer-in-charge. Replacing of the cassette baffles after the repair job. Newcassette baffles will have to be used wherever the old cassette baffles are damaged as per theinstruction of the engineer in charge.

The procedure will be as follows: Cut the saddle supports along with hanger tube with cuttingtorch carefully with out damaging the horizontal LTSH tubes. Clean the LTSH tubes by grinder.Support the LTSH tubes properly. Insert the new hanger tube in position. Support the LTSHtubes with U clamps after welding them and placing the resting pads in between as per theinstruction of the engineer in charge. If necessary, the LTSH tubes can be cut wherevernecessary and reweld them by H.P. welders after the hanger supports are placed in position, but

no separate payment will be given for such joints

Identify the area where fin welding is to be done with engineer-in-charge.Cut the M.S. plate of 3.15 mm /2.5mm thick sheet to proper size and grind the edges properly

so as to fit the fin in the tube gaps perfectly. Removal of sheet casing over the identified area.Whenever fin is cut, it must be ensured that adjacent tube is not damaged. In case the tube isdamaged, the same shall be replaced free of cost. Welding of the fins on both sides of tubeswill be done by approved/tested welders only.

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Scope includes:Identify the area where shielding is to be done with the engineer- in-charge.

This includes over bends, straight tubes, headers etc. Shields will be supplied by NTPC but thesame will have to be cut in to proper size, make minor alteration so as to fit on bends as per theinstruction of engineer-in-charge. Workshop facilities can be availed for cutting of these shieldsdepending on availability. Shielding is to be carried out on screen tubes, supply tubes etc. Incase of economiser bends, the shielding will have to be provided over the bends on front sideand rear side. Sufficient gap for the above work will have to be made by pulling the coils apartusing chain pulley or hook chook.

.Size of the joint up to and including size 77 mm ODRadiography may be taken at all the areas for any size up to and including 77mm OD tube/joints of any thickness and any type of material.

Scope includes, Opening of both the man holes , cleaning of drum internal, minor and local repairs

with in side the boiler if any, changing of the man hole gaskets, boxing up of the boiler drum with newgasket, hot tightening of the drum man hole after the light up of the boiler at appropriate pressure asper the instruction of the engineer in charge

Cutting and removal of old/damaged sheets from boiler as per the instruction of engineer in charge.

Welding of New plates cut in size with complete seal welding.

Area includes left, right, and rear sides of LTSH, Economiser and before and after of screen tubearea. The procedure is as follows Identify the area with the engineer in charge. Weld supportangles (50 mm size) of 6 to 10 inc. lengths at a gap of 1 feet along the steam cooledwalls/extended waterwall area. Weld M.S. flat/ S.S. angle connecting all the support angles tosupport the wire mesh. Roll the wire mesh in suitable size so as to fill the gap fully and placethem in the space between the coils and the steam-cooled wall from bottom to the top elevationof the coil. Cut the S.S. wire mesh into proper size so as to fit into the screen tube area. Makecomplete locking of the wire mesh with the S.S. angle.

The scope is to do the thickness survey of various pressure parts of the entire boiler in the area ofwater wall, Economisers, Super heaters, or any other area as per the instruction of the engineer incharge.The thickness survey will have to be carried out by qualified techniciansThere should be sufficient D-Metering machines (minimum 2 teams with machines) so that the D-metering will be completed in the stipulated time. The D-Metering will be done after proper cleaning ofthe surface where thickness is to be measured.The agency should have tools, Buffing machines, wirebrush, emery paper etc. for the cleaning required for the D-Metering

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Identify the area where inspection is to be done with the engineer- in-charge. This includes cornerbuckstays and vertical buck stays at LHS & RHS of second pass from 33m to 52 m. Erect scaffolding ateach corner to facilitate cleaning, inspection and repair of buckstays. Removal of Aluminium corrugatedsheet casing over the identified area. Prepare the corner buckstays (approx. 1.5-m on both side) bybuffing, emery paper cleaning for Dye Penetrant Test between welding of buckstays with Steam Cooledwall after the removal of insulation. Do Dye Penetrant Test at the corner of the buckstays. Identify thedefects of buckstays, channel, stirrup plates, beams, angles, etc with engineer-in-charge. Rectify thedefects that include removing the scallop bar from the steam-cooled wall and reinstall the scallop barby welding or any attachment welding by approved/tested welders. Rectify any defects if any persiston buck stays.

Assembly of coal nozzle with coal nozzle tip, seal plate, nozzle support tilting lever etc.with proper marking as directed by engineer in charge.

Insertion of coal nozzle assy. in coal nozzle compartment housing.

Making the tip position horizontal.Repair / replace the external casing.Fixing of external casing and internal casing.Shifting of material to burner floor.Arresting of P.C. lines properly.Dismantling of victaulic coupling on both ends of fuel inlet elbow by opening their nuts

and bolts.Removal of fuel inlet elbow.

Removal of external casing and insulation.Removal of coal nozzle with its tip.Dismantling of tips, coal nozzle support, seal plate, tilting lever etc. and marking on

them as desired by Engineer In charge.Placing of new / repaired elbow in position.Fixing of victaulic coupling by tightening the nut and bolts (It should be ensured that no

leakage takes place from the coupling)

1. Shift the material to site.2. Make necessary scaffolding.3. Arrest P.C. Line on both ends of the bends.

4. Dismantle the bend support if any.5. Cut the straight P.C. Pipe of meter to 1 meter length towards the burner side of the

bend except in case of 90O bend. In case of 90O bend cut the straight P.C. Pipe towards millside.6. Check the condition of bend. If ceramic portion of bend is damaged, replace the bend.Otherwise reverse the bend.7. If the bend to be replaced is an off set bend then contractor has to fabricate the bend atsite and no extra charge will be paid to the contractor for fabrication of bend.8. Now check the condition of straight P.C. Pipe. If it is damaged then replace it otherwiserotate / reverse the straight P.C. Pipe.

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9. Also replace straight P.C. Pipe at the outlet of mill outlet elbow of to 1 meter lengthas per requirement.10. Now lift the straight P.C. Pipe and weld it on one side with P.C. line and other side withceramic bend.11. The length of P.C. Pipe to be replaced / reversed may vary from meter to 3 meters asper requirement of site.12. Fix the bend support if any.13. Remove P.C. line arrest.14. Remove scaffolding.15. Remove scrap to scrap yard.

1. Shifting of materials to the burner floor.2. Erection of scaffolding ( If required)3. Arrest P.C. line properly on both ends.4. Dismantling of victaulic coupling by opening the nuts and bolds.5. Remove the old orifice.6. Place the new orifice at the right position.7. Change the victaulic coupling gasket.

8. Fix the victaulic coupling by tightening the nuts and bolts.9. Cutting of p.c. pipe arrest.10. Removal of scaffolding.11. Removal of scrap to scrap yard.

1. Shifting of material to the site.2. Make necessary scaffolding.

3. Arrest p.c. line of both ends.4. Dismantle the victaulic coupling by opening the nuts and bolts.5. Remove the elbow.6. Replace the collar of p.c. pipe on both the ends.7. Place the elbow in position and align it properly with p.c. line.8. Fix the victaulic, with its gasket replaced by tightening the nuts and bolts.9. Removal of P.C. line arrest.10. Removal of scaffolding.11. Removal of scrap to scrap yard.

1. Shifting of material to the burner floor.2. Cut the damaged and the warped plates in the air compartment, coal compartment

and oil compartment and the corner walls and wind box.3. Weld new plates properly.4. Remove the scrap.

1. Shift the material from the store to burner floor.2. Take out all the air compartment tips.3. Repair / replace air compartment tips.4. Place them back in position.5. Replace damaged pins and pin holding sockets.

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6. Adjust them to horizontal position before connection their levers to the tiltingmechanism.7. Remove the scrap.

1. Shift the material from the store to burner floor.2. Take out all oil gun assembly and oil guns.3. Take out all oil compartments.4. Repair / replace oil compartment tips.5. Place them back in position.6. Repair oil gun assembly and place them back in position.7. Put the casing back in position and tag weld it.8. Remove the scrap.

i. Air pre heater ash hoppers 4 Nos. for each Unit.ii. Economizer ash hoppers 4 Nos. for each Unit.

1. Dismantle the flushing apparatus and remove them from the position, Weld 12/14 mmthick plate at the bottom and 10mm thick plate all along the curved portion.

2. Repair / replace flanges and pipe connected to them. Welding should be done properly,3. Repair / replace the nozzles and the pipe connected to it.4. Replace the ash disposal pipeline of N.B. 300 mm wherever damaged as per instructionof engineer-in-charge.

5. Dismantle all the valves and distance piece. Flush the line and service the valves andassemble them back in position.6. Clean the ash hoppers and discharge pipe connected to them. They should be free fromash and all foreign materials.

K. Take out scrapper conveyors from its position.1. Remove 11 link chain, special link and scrapper bar.2. Remove all the guide pulleys, tail guide pulleys, head shaft assembly, return guide wheelassembly etc.3. Dismantle double roller chain.4. Remove fluid coupling by opening nuts and bolts.5. Remove gear box from its position.6. Thoroughly clean trough body of scrapper conveyors.7. Remove damaged side walls, supports, liners and weld new plates of required thickness

and supports.8. Remove all rust from the body of scrapper conveyors.9. Service all leg wheel assembly and ensure free movement of leg heels.10. Put back serviced / repaired guide wheel assembly, tail guide wheel assly., return guidewheel assly., head shaft assly. And tighten their nuts and bolts.11. Place back gear boxes in position and do the alignment along with the fluid coupling andmotor.12. Put back double roller chain in position.13. Place new chain, special link and scrapper bar.14. Paint the scrapper conveyors.

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15. Take trial run of scrapper conveyors.16. Commissioning of scraper conveyors.17. Water should not leak from the trough body.18. Pull back scrapper conveyors back in position.19. Remove scrap to scrap yard.

1. Shift material from store to site.2. Cut and remove the old compensator completely.3. Fix the new compensator in position.4. Weld it completely with the existing frame.5. Now weld plate of 3.15 mm covering this compensator on all the four sides (welding ofthis plate should be done only on one side as per instruction of engineer incharge.)6. Remove the scaffolding and shift the scrap to scrap yard.

a). E.P. inlet. b). A.P.H. inlet & outlet.. Qty. : 150 Mtrs.i Shift old / used economizer tubes or M.S. pipe to the site.

ii. Open manhole doors of the duct.iii. Clean the duct.iv. Make proper lighting in the duct.

v. Make thorough inspection of the duct for damaged duct supports.vi. Cut and remove the old supports and weld new ones.vii. All New Pipe supports to be covered with angle on one side as per

Instruction of Engineer In Chargeviii. For Duct support, old pressure parts tubes can be used

as per instruction of Engineer- in- charge. .ix. Remove the scrap and dispose it off to the scrap yard.x. Remove the extra material from the duct.xi. Clean the duct properly.xii. Close the manholes with asbestos rope put in its groove.

i Shift the material from store to site.ii. Cut a slit in the duct for inserting the plate in it.iii. Make thorough inspection of the duct for identifying the area where duct / ductbaffles are damaged.iv. Remove old / damaged plates and baffles and Weld New ones.v. In case of even partially damaged baffles, it should be replaced completely.Welding should be done on both sides of Baffles.

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vi. All baffles are to be bent in workshop as per the originalprofile as per instruction of Engineer-In- Charge.vii. The thickness of the plate is decided by Engineer Incharge.

i Shift 10 mm M.S. Plate from store to site.ii. Cut a slit in the duct for inserting the plate in it.iii. Make proper scaffolding wherever necessary.iv. Make proper lighting arrangement in the duct.v. Remove all damaged / worn out plates, earlier patched, upto the original plate.vi. Baffle grid is to be made before ESP inlet duct mouth as per the Instruction ofEngineer-In-Charge.

1) Raise proper scaffolding.2) Cut the damaged portion of dipbox as per the instruction of engineer-in-charge.3) Place the 12mm plate in position and weld it.

4) Strengthen the dipbox with angle, channel as per the instruction of engineer-in-charge.5) Shift the scrap to scrap-yard.

1 After removal of burner panel and coal nozzle assly. Dismantle all the parts ofburner tilt mechanism.

2 Repair/Replace Burner Frame wherever damaged.3 Fabricate the burner frame wherever required.

4 Reassemble all the parts of burner tilt mechanism .5 A manhole of size 300x 200 mm is required to be fabricated and erected

at wind box side for Coal Nozzle Assembly' 0'setting.

6 Commission the Burner Tilt Mechanism after errection of all Coal NozzleAssembly, Aux. Air Damper & Oil Gun Compartment etc.

7 Tilt Mechanism should operate + 30 to -- 30 degree freely.

1. Open the manholes after the unit shut down and the ID Fans are in stopped condition.

2. Remove the top covers of the zones for water washing & restore the same after completion ofthe work.

3. Clean all the ESP internals, Screens, Inlet ducts & roof with water.4. Scrap the collecting plate and insulators with wire brush after the water washing completed.

5. Replace the asbestos rope in the man holes and close the man holes after completion of thejob. Tighten the clamps holding the man holes; if necessary replace the eye bolts.

1. Shift materials from Store to site and scrap to the scrap yard.

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2. Cut the bolts nuts and remove the damaged hammers as per the instructions given by theEngineer-in -charge.

3. Fix the new hammers on the shaft and tightening them with new bolts and nuts.

1. Shift the materials from Store to Site

2. Dismantled the damaged bearings and fix the new ones one by one with out disturbing the

shaft position.3. Tacks weld the nut with the bolt after tightening.

4. Dispose off the scrap to the scrap yard.

1. Shift the materials from Store to site and dispose off the scrap to the scrap yard.

2. Cut and remove the bolts, nuts supporting the shock bars.

3. Remove the shock bar from the position.

4. Replace the new shock bar back in position and tighten the bolts and nuts.

5. While putting the shock bars in position the collecting plates should be in perfect alignedcondition with respect to each other.

1. Shifting of materials from Store to site and dispose off the scrap to the scrap yard.

2. Cutting/Removal of the damaged portion of the guide bars from position.

3. Place the repaired/new guide bars in position.

4. Weld the guide bars with each others by tube Couplers keeping the gap between collecting

and emitting electrodes uniform in all the parts.

1. Shifting of materials from Store to site and dispose off the scrap to the scrap yard.

2. Straighten the collecting electrode by proper clamping and weld it if necessary.

3. Repair the bottom plate holding shock bars, if necessary.

4. Ensure no damage should occur to the adjacent plates while working.

1. Shifting of materials from Store to the site and dispose off the scrap to the scrap yard.

2. Erect the scaffolding before Primary screen and in between primary and secondary screens.

3. Map the position of baffle plates prior to the removal of damaged GD screens.

4. Remove the damaged/worn out GD screens from position

5. Cut the new GD screen plates to required dimension while taking care of pitch. -

6. Fix the screen plates in position. And Restore the baffle plates as per the mapping

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2. Cut and remove the damaged portion from hoppers, manholes and discharge pipes.

3. Cut the new MS sheet of 3.15/5mm according to the sizes and fix it in the position and weld.

4. Replace the asbestos rope and close the manhole doors


2. Remove the damaged shaft (after dismantling all the hammers) by dismantling of plainbearings.

3. Check the shaft for straightness and straighten it if necessary.

4. Fix the new bearings on the support frame by checking the level with water level indicator.

5. Keep the shaft on the bearings and align the shaft holes matching with the shock bars.

6. Insert the tube coupler over the shaft and weld the shaft with the tube coupler (pre-heating isto be done prior to welding).

7. After fixing of upper bearing tack weld the nuts with the bolts.

8. Provide the stoppers on both sides of the bearings at two places to prevent shifting of shaft.

9. Fix the hammers in position and tighten the nuts and bolts.


2. Dismantle the flushing apparatus from position by opening the bolts and nuts.

3. Cut and remove the damaged portion of the flushing apparatus.

4. Cut the pieces according to the size from the new plate of 12mm size, and fabricate thepipe if necessary.

5. Fix the new pieces in position and weld the same with proper procedure after the edgepreparation. Paint the apparatus.


2. Remove the valves & nozzles from position by opening nuts & bolts by spanner.

3. Cut & remove the damaged nozzle from the position and weld the new nozzle.

4. Cut & replace the damaged portion of the water pipe and prepare bends if necessary.

5. Dismantle the valve completely and service the points and box up the valve.

6. Prepare the new gaskets and f ix the nozzles and valves in position and tighten the nuts &bolts.

1. Shifting of materials from stores and removal of scrap to the scrap yard.

2. Cutting &removal of bolts &nuts of the damaged shock pads.13


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3. Replace the new shock pads in position, tighten the bolts and tack weld.

4. Cutting of 50x50 angles in 50mm length. Fixing of these pieces over the guide bars/ guideplates and weld them with the guide bar/plates.

1. Shifting of materials from stores and Removal of scrap to the scrap yard.

2. Cutting & fabrication of supporting brackets.

3. Fixing of Brackets as per the instruction of engineer in charge.

1. Decouple the gearbox from the rapping shaft.

2. Remove the lube oil and store it in empty drums.

3. Decouple the motor from the gearbox.

4. Dismantle the smaller unit of the gearbox from the bigger box.

5. Open the central bearing (isolated from the both boxes) and grease the same.6. Check the bearings and gears for any damage and replace them if necessary.

7. Prepare the new gaskets from the oilpaper.

8. Assemble the gearboxes and couple the motor with the gearboxes.

9. Check the couplings for any damage and repair the same.

10. Take the trial run and check the direction of rotation.

11. Couple the geared motor with the rapping shaft.

1. De couple and remove the gearbox from position.

2. Remove the damaged insulator from position.

3. Check the rapping shaft for any jamming.

4. Insert the new insulator in position and couple the gearbox aligned.

1. Shifting of required spares from stores to the site.2. De-couple the fan from motor and take bearing and coupling alignment readings as per the

instructions of the Engineer-in-Charge.3. Inspection and servicing of inner and outer bearings.4. DPT/MPI of Impeller.5. Servicing of Inlet Guide Vane unit assembly including replacement of all the damaged vane

assemblies.

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6. Servicing of discharge damper assembly.7. Repair of impeller casing, fixed blade casing & fixed blades as per the instructions of the Engineer-

in-Chanrge.8. Repair/Fabrication of cooling tube and fabrication of cooling fan casing.9. Servicing of motor lube-oil system.10. Successful commissioning of the fan.11. Painting of IGV assembly and impeller casing with a single coat of red-oxide paint.

1. Cleaning of fan internals, blades, suction chamber, Diffuser up to discharge damper.2. Servicing/ Repairing of discharge dampers and fan casing.3. Servicing / Repairing of lub. Oil coolers including oil filters, oil tank.4. Replacement/ Repairing of cooling water header and valves including cooling water drain line.5. Painting of fan casing, lub oil tank, lub oil lines etc.

1. Lift the top half of the main bearing assembly.2. Remove the coupling both fan side and motor side, free the intermediate shaft.

3. Remove all the connections of main bearing assembly and servo motor assembly.4. Remove the distance piece and shift the diffuser towards discharge damper.5. Remove the impellar blades.6. Remove the blade bearing assembly with servo motor assembly.7. Remove the main bearing assembly.8. Servicing of servo motor assembly9. Pressure testing of all blade10. Dismantle the main bearing assembly.

11. Inspection/replacement of damaged parts including bearings.12. Re-assemble the main bearing assemble.13. Mounting of main bearing assembly.14. Mounting of blade bearing assembly and servo motor assembly.15. Mounting of blades on blade bearing assembly.16. Positioning of diffuser and distance please.17. Coupling and alignment of fan with motor.

1. Shifting of required spares from store to site.2. Decouple the fan from motor and take alignment reading.

3. Remove the top half of the casing.4. Remove the impeller assembly as per instruction of Engineer-in-Charge.5. Replacement/ servicing of IGV assembly.6. Servicing of discharge damper assembly and shut off gates, including repair of damaged flaps and

shut off gate.7. Repairing of discharge duct upto discharge damper.8. Checking/ repairing / replacement of bearing pedestal by DPT.9. Blue matching/ leveling of pads of pedestal with surface plates.10. Mounting the impeller assembly with shaft and housing on bearing pedestal (bearing assembly

already available).

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11. Inspection / cleaning of bearings and impeller.12. Cleaning of impeller for D.P.T.13. Box up of the fan , alignment & leveling of shaft on pedestal.14. Alignment of fan with motor and couple as per instruction of Engineer-in-Charge.15. Servicing of lub oil system & replacement of damaged parts.16. Successful trial run and dynamic balancing.

1. Remove the distance piece.2. Remove the side casing cover.3. Dismount the impeller from motor shaft.4. Repair/Replacement of all the suction & discharge side dampers.5. Inspection/ Repair of motor foundation.6. Replacement/ Repair of Suction & discharge line including its hangers.7. Mount impeller on the motor shaft, assemble the fan casing & alignment of fans.

8. Trial run of fan, balancing of fans if required.

1. Removal of ash, debris, refractory etc. and cleaning of entire APH area around guide bearing,

inside APH.

2. Servicing of Air motor. Replacement of fluid coupling and subsequent alignment of motor to

gearbox, oil replacement of 5APC gear box.

3. Gear box and pin-rack alignment checking and correction (adjustment of gear box only).

4. Servicing/ repair/replacement of 5APC gear box

5. Replacement/readjustment of all seals of hot end and cold end radial, axial, bypass, sector plate

to axial plate seals and rotor post.

6. Inspection of static seals at H.E inboard and outboard after removal of cover plates, replacing

the kao-wool and repair of static seal if required by welding or replacing of cover plates.

7. Repair/replacement of T-bar and machining of new T-bar as per the instruction of the engineer

in-charge.

8. Hot End Gas side Compensator replacement

9. APH hot end duct repair

10. Axial seal plate replacement

11. Checking of run-out of T-bar and its correction to the extent possible and minor repair of T-bar

like worn out nut/bolt replacement, hole plugging.

12. Leveling of rotor and all sector plates viz. H.E, C.E and axial seal plates within specified limits.

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13. Servicing/repair of cleaning devices, soot blowers & replacement/servicing of water washing

manifolds, and of associated water washing valves and soot blower nozzle, 90 deg. bend and

other damaged parts.

14. Repair of center section, triangular section (and laying a layer of refractory), APH static sections

up to the compensators (expansion joints) in air and gas sections.

15. Removal of packing cover ring and packing retainer cover. Replacing of kao-wool and packing

rope and putting back of packing cover ring and retaining cover.

16. Servicing of lube oil systems of both guide and support bearing.

17. Removal of guide bearing housing cover, inspection & oil flushing of bearing.

18. Removal of support bearing housing cover and inspection of support brg. and checking of

support brg. housing level, oil flushing of support bearing.

19. Removal of all baskets for jet cleaning and putting them back after repair work

20. Baskets reversal/replacement

21. Support and guide brgs inspection and replacement if needed

22. Trial run. Correction of defects, if any.

1. R. C . Feeder bed plate replacement (Quantity : 5 nos. approx)

2. Drag Link Chain Replacement wherever necessary

3. Bunker plate replacement wherever necessary

4. Upper guide shoe replacement by using 5mm SS plates wherever necessary

5. R C Feeder D.E. Brg. replacement (Quantity :3 nos.)

6. R C Feeder Tension head Brg. Replacement (Quantity : 3 nos.)

7. Variator and gear box checking & servicing . (Quantity :6 nos)

8. Replacement of Vertical portion of R.C. Feeder (Quantity :1 nos)

9. Two part rim replacement (Quantity : 8 nos)

10.Painting of R.C.Feeders ,gear box with vertical portion. (Quantity :6 nos)

11. Replacement of Variator and gear box checking & servicing (Quantity:2 nos

Inspection &checking of all 6 nos bunker gate assembly. Replacement of shear pins ,all 6 nos Gear

box checking ,oil level checking & single roller chain tightening wherever required. Replacement of felt

packing system to prevent coal & air leakages.

DENSEVEYOR SYSTEM :

1. 100 NB conveying pipe line replacement ( Quantity : 200 MTRS approx)

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2. Cleaning of pyrite hopper and clearing of line choking in denseveyor system and overhauling of

all the 6 nos. denseveyor system

3. Maintenance of all pneumatic gates (150 mm & 200 mm) of Denseveyor system including their

replacement

4. Attending to jammed Dome valves by taking out the spacer pipe between pyrite hopper and

conveying vessel wherever required.

5. Clearing of all hose pipes and air/impulse pipes and their end-connections.

6. Disassembly and assembly of Dome valve assembly and conical vessel assembly and servicing .

7. Dismantling of the conveying vessel and tapping of all threaded holes with suitable taps. &

following to be done .

a) Replacing/ repairing of outer bend cleaning ring ( OBCR ) .

b) Replacing of 45 degree cast iron bend after outer bend cleaning ring .

c) Repair/replacement of dome valve, dome valve shaft, dome body, dome shaft bearing

and shaft seal retaining ring etc .

d) Replacing /servicing of main blow valve and blow pipe .

e) Replacing of all elbow , bends , Tee joints, unions etc in the system Repairing/ replacing

of pyrite hopper and its man holes by fabricating MS plates wherever necessary and

replacing inside grills of pyrite hopper.

f) Dismantling of TIG mouth assembly and fixing of SS plates by fabrication in TIG mouth

assembly wherever necessary

SCOPE OF WORK UNIT IV( Annual O/H)- Milling System

1. Roller and bull ring replacement (Quantity: 2 set.)

2. Roller, bull ring, support replacement & associated work. Activity C (2 nos.):

3. Gear box sealing system inspection & overhauling.(if required) (Quantity : 2 nos.)

4. Worm shaft bearing checking & replacement (if required) (Quantity : 2 nos.)

5. Lower bearing checking & replacement (if required)(Quantity : 2 nos.)

6. Replacement of orifices. (Quantity : 18nos.)

7. Replacement /Repair of MDV. (Quantity :1 nos.)

8. Replacement /Repair of inner cone. (Quantity : 2 nos.)

9. Gear coupling inspection & replacement (if required) (Quantity-6 nos)

10. Bowl mill overhauling (Quantity :2 nos.)

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11. Repair / fabrication of hot air duct (Quantity =25 Sq. Mtr.)

12. Replacement of HAG Plates (Quantity : 3 nos.)

13. Replacement of R.C. Feeder chute (Quantity : 1)

14. Repair/Replacement of Hot air Damper (Quantity-6 nos)

15. Repair/Replacement of Cold air Damper (Quantity-3 nos)

16. Servicing of Hot air Gates (Quantity-6 nos)

17. Servicing of oil coolers (Quantity-6 nos)

18. Replacement of centre feed pipe 6 nos

19. Replacement of PC pipes 50 meters

Maintenance of air blasters in three RC feeders each of unit 4 - during overhaul

Apart from monthly regular checking and any breakdown work in between.

Contract for two years

Total no of blasters 48

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1. Removal of thermal insulation of the turbine components and piping to facilitate the dismantlingof the three casings.

2. Hot loosening of the HP and IP turbine parting plane studs and cap nuts. Where evernecessary the cap nuts and studs are to be cut as per the instruction of the engineer in charge.Loosening of the LP casing parting plane bolts.

3. Lifting of the top halves of the HP, IP and LP casings.4. Removal of the barring gear and the bearing top covers.5. Taking the alignment readings and de-coupling the HP- MOP, HP- IP, IP-LP and LP- generator

rotors and taking the alignment readings.6. Checking of the bearing interference and oil clearances. Repairing of the bearing

pedestals if required at the places of the load bearing areas.7. Checking rotor run outs and journal slopes.8. Checking steam flow path clearances and float of the rotors.9. Lifting of the HP, IP and LP rotors.10. Removal of the bottom diaphragms and liners.

11. Cleaning the parting planes of the casings and checking the thermal distortion of the surfaces.12. Rectifying the thermal distortion of the parting planes ( to the extent required in consultation

with the engineer in charge) of the casings, carriers and diaphragms by welding and bluematching. Flange heating groove to be rectified if required. All welding to be carried out by acertified high pressure welder. The flange and stud heating chamber joints are to bechecked for any leakage and are to be repaired and tested with compressed air.

13. Removing and re-visioning of the sliding keys and foundation bolt washers of bottom LP casing.DP test of LPT and condenser neck joint and repair as per requirement.

14. Cleaning of all the components including rotors and diaphragms, manually or by sand blastingor by wet sand water jet blasting, with the consent of the engineer in charge. The equipmentincluding the air compressor/ high pressure jetting pump/ consumable items for thesandblasting job are to be brought by the contractor. The material required for erecting thetents will be provided by BTPS. In case of dry sand blasting the job is to be done outside theturbine hall. For this the shifting of the components is to be done by the contractor, howeverthe EOT/ mobile crane and trailer will be arranged by BTPS.

15. Dye penetrant testing is to be carried out of the casing and nozzle box areas, rotor anddiaphragms and all stubs attached to the casing. If any defect is noticed the same is to berectified/ replaced as per BHEL norms at contractor's cost by BHEL welder.

16. Repair of the damaged threading of the casings, bearing pedestals and bearing covers bydrilling / reaming followed by tapping of higher sized taps if necessary. Any dowels or locatingpins if required are to be reamed to new sizes and to be replaced.

17. Seal bore readings are to be corrected wherever feasible and required.18. Re-visioning/ replacement of all the bearings after the DPT and Ultrasonic testing and

readjustment of the bearing clearances as per standard values and re-assembly.19. Alignment of rotors and finalizing the positioning of the bearings. The semi coupling on the IP

rotor towards the LP rotor is to be replaced with a new one if the de-coupled run out as the runout the same has recorded higher than permissible in the previous overhaul.

20. Removal of the front bearing pedestal and ensuring the slidability of the same and carry out therepairs if any needed for the same.

21. Float adjustment after checking / replacement of thrust pads of bearing no 2.22. Centering of all the diaphragms and internals.23. Check / adjust steam flow path clearances, axial float, seal clearances, and thermal

clearances. Machining jobs required for this purpose will be done by BTPS, however welding

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and matching ( of diaphragms, gland boxes, liners etc.) to be done by the contractor. If newpeak seals are fitted in the diaphragms, the clearances of the same are to be made by thecontractor.

24. Bump/ sling check of the rotors to be done.25. Replacement of the HPT and IPT parting plane fasteners wherever necessary, boxing up of the

HP, IP and LP casings and tightening of the fasteners.26. The external surfaces of the HP, IP, and middle part of the LP casings are to be thoroughly

cleaned and then painted with heat resistant Aluminum paint. The paint will be supplied byBTPS.

27. Checking the final alignment and making the final corrections. Checking the bearinginterference and corrections to be done.

28. Reaming of the coupling holes and coupling the rotors by fixing new/ old coupling bolts as isnecessary. The machining of the coupling bolts will be undertaken by BTPS.

29. Preparation for oil flushing and normalizing of the bearings. For the purpose of oil flushing, ifsome of the bearings are required to be bypassed / blanked, the same is will be done by thecontractor. Cleaning of the line filters and the MOT filters whenever required during oil flushingand till unit is handed over.

30. Assembly of the cross over pipelines and the leak off and the sealing steam lines.31. Rectification of any defects during the rolling or on barring gear or during over speed testing.

32. Trim balancing of the rotor system if required.33. The scope of work includes the following also.

a) Replacement of rotors with the available spare rotor if required and replacement ofcomponents like lacing wires, shroud band segments and lacing tubes to be done by thecontractor. Replacement of the stellite strips of the LP blades if the existing strips are founddamaged is to be done by the contractor.b) During the process of dismantling and boxing up, the relevant checks in respect tothe clearances, interference, alignments, corrections are to be carried out as per BHEL

standards and cross checked with the readings of the previous overhauls, available withTMD.c) Servicing of the oil system valves.d) Overhauling of the barring gear and replacement of its coupling with a spare one.e) Re-visioning of the governing system along with CVSM, control valves of HP and IP withoperating mechanism, cam shafts, ESVs and IVs. Lapping and blue matching of the valvesare to be done. The liners and valve internals of the control valves and other components of thegoverning system and CVSM are to be replaced if found defective. Re-visioning of amortizer ifrequired.f) Re-visioning the MOP rotor as per BHEL protocols.g) Re-visioning and cleaning of the MOT and it's internal components like injector etc. Repair ofthe MOT filters, cleaning of oil out let lines from the all bearing pedestals up to the firstinspection windows at the time of final box up of the pedestals.h) Checking and adjustments of the Governing characteristic.i) Shifting of the spares and consumable items to the site from the store and shifting of the

unused material and scrap from site to the scrap yard or to stores.j) Any rerouting/ modification of pipe lines/ flanges at turbine floor, directly connected to theturbine are required to be done if found necessary.k) As soon as the turbine cylinders are opened, all the steam, extraction and drain lines are tobe plugged with wooden plugs/ sheet metal and kept in place till the time of box-up to avoidany ingress of foreign materials into the connected pipe lines.

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1. Booster pump overhauling.

2. Working oil coolers cleaning

3. Hydraulic coupling inspection.

4. Sent water cleaning.

5. Strainer cleaning.

6. Bearing intigration.

7. Replacement of cartridge/pump if required.

B. The job includes:

1. Inspection of Gland packing , replacement if required.

2. Replacement of oil.

3. Inspection of Thrust bearing.

4. Inspection of Suction strainers.

5. Inspection of couplings, bolts, bushes.

6. Replacement of pump with new assembly if required.

1. Inspection of bearings.

2. Inspection of Gland sleeves & replacement if necessary.

3. Inspection of Cooling chamber.

4. Inspection of Coupling & Alignment.

5. Replacement of pump if necessary.

1. Removal of motor after decoupling.

2. Opening of discharge flange.3. Opening of base bolt.

4. Lifting of pump for checking, placement of pump if found O.K.

5. Replacement suction bowl & suction seat section.

6. Tightening of Flange bolts.

7. Checking of pump shaft coupling, stuffing box.

8. Filling of Gland.

9. Replacement of pump if necessary.

1. Inspection of coupling & alignment.

2. Gland sleeve replacement if necessary.

3. Bearing replacement if necessary.

4. Rotating assembly replacement if required.

5. Base repair if required

1. Inspection of coupling & alignment.

2. Inspection of bearings, replacement if required.

3. Inspection of Glands & replacement if required.

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4. Inspection of coupling bolts, bushes & replacement if required.

1. Inspection of pumps.

2. Inspection of bearings.

3. Checking of cooling coils.

Cleaning, attending to leakages if any.

1. Opening of man holes.

2. Cleaning of condenser tubes by jetting pump.

3. Checking of spray header, repair if required.

1. Removing of plate bolts.

2. Removing of strainer.

3. Repairing of cover plates by welding of M.S ring inside.

4. Fitting of strainer.

5. Tightening of flange bolts & filling gland.

1. In case of tube leakage particular heater will be taken. Leakages will be intimated be Opn.Department.

Not to be taken up.

1. All defects pending.

2. All defects intimated by PBC/Operations.

3. Modifications as suggested by PBC.

4. Defects noticed by TMD.5. Condenser flood test leakages.

1. Checking of pump-motor alignment.2. Checking of brake shoe coupling.3. Checking of pump seals.4. Bowl cleaning & healthiness of bearings5. Cleaning of heater.

F.S.T. inspection/repair.Cleaning & inspection.

1. Tube leakage attending, if any2. Nozzle gap checking.

1. Tube leakage attending, if any2. Oil line thick ness3. Oil line weld joint inspection4. Ejector bend thickness

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1. Bowll Mill Motors - 6 Nos.

2. I.D.Fan Motors - 2 Nos.

3. F.D.Fan Motors - 2 Nos.

4. P.A.Fan Motors - 2 Nos.

5. CEP Fan Motors - 3 Nos.

6. C.W. Motors - 2 Nos.

7. Boiler Feed Pump Motors - 3 Nos.

8. SOP motor - 1 No.

1. Decouple trail run and ascertaining the Bearing condition.2. Dismantling of all motors.

3. Threading out of the rotor.4. Cleaning of stator and rotor with M.T. Oil / G.P Thinner & CTC.5. Inspection of rotor bars, stamping, stator winding, lacing, wedges, stamping etc.6. Heating of stator.7. Testing the stator for P.I. value.8. Varnishing of stator & rotor.

9. Cleaning & re-greasing of bearings / replacement of brgs. (if required).

10. Inspection of motor leads & star points and main terminals.11. Threading in of rotor and assembly of motor.12. Decoupled trial run after overhaul.13. Painting of motor external surface.

1. Scraper conveyor motors - 4 Nos.

2. Clinker Grinder motors - 2 Nos.

3. P.A. Fan Motor Lub oil motors - 4 Nos.

4. R.C. Feeder motors - 6 Nos.

5. R.C. Feeder LOP motors - 6 Nos.

6. FD fan lub oil motors - 4 Nos.

7. ID fan lub oil motors - 4 Nos.

8. Phosphate dozing pump motors - 3 Nos.

9.Hydrazine dozing pump motors - 2 Nos.

10. Seal air fan motor - 2 Nos.

11.Air pre heater motor - 2 Nos.

12.APH Guide Brg. LOP motor - 4 Nos.

13.APH Support brg. LOP motor - 2 Nos.

14. Ignitor fan motor - 2 Nos.

15. Scanning fan motor - 2 Nos.

16.Aux. PRDS motor - 1 Nos.

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1. Stator water pump motors - 2 Nos.

2. CW Booster pump motors - 2 Nos.

3. Drip pump motors - 2 Nos.

4. Sump pump - 2 Nos.

5. A.C. Seal oil pump motor - 1 Nos.

6. DC Seal oil pump pump motors - 1 Nos.

7.Centrifuge motor - 1 Nos. (Horizontal)

8. B.F.P. lub oil pump motor - 3 Nos.

9. Barring gear motor - 1 Nos.

10.Vaccum pump - 1 Nos.

11.A.C. lub oil pump motor - 1 Nos.

12. DC lub oil pump motor - 1 No.

13.Vapour fan motors - 3 Nos.

14. ELP motor - 2 Nos.

1. Decoupling of motor.2. Shifting of LT motor to working shed.3. Dismantling of motor.4. Threading out of rotor.5. Inspection of rotor & stator stamping & windings after cleaning with CTC.6. Inspection of bearings to find out condition of bearings for replacement if required.7. Heating of stator for complete drying.8. Varnishing of stator.

9. Cleaning & re-greasing of Bearing / replacement if required.

10. Assembly of motor.11. Paining of motor (external surface)12. Decoupled trail run of motor.

1. 6.6 KV HT Board - A & its associated feeders

2. 6.6 KV HT Board - B & its associated feeders3. Overhauling of ACB, SF 6 Breakers.4. Retrofitting of 5B1 breaker and Spare panel.

1. Meggaring of bus bar for IR value before starting of overhauling.

2. Busbar cleaning.3. Opening of busbar bar compartment.4. Cleaning & inspection of bus bars, joints, insulators, upper fixed contacts.5. Boxing up of busbar compartment.6. Opening & cleaning of CT compartment.7. Cleaning of CT's and cable termination as well as checking of such terminations and fixed contacts.8. Boxing up of CT compartment.9. Cleaning of Breaker cubicle.10. Tightening of control wire terminations at Therminal block and cleaning of switches.11. Meggering the bus after overhauling.

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12. Charging the Bus bar after checking protections.

1. Checking of contact resistance of all three phases (poles) of all breakers.2. Inspection of moving contacts, fixed contacts, and sundry apparatus after draining oil. Replacement

of parts if required.3. Inspection & cleaning of Arc Chutes.4. Assembly of interrupter chamber, filling with oil.5. Cleaning & lubrication of spring charging mechanism.6. Inspection of breaker operation.7. Measurement of contact resistance / Pole continuity checking after overhauling is completed.8. Jaw contacts matching / alignment with busbar fixed contacts.9. Manual / electrical operation checking for spring charging, close & open. Operation.

1. Checking of contact resistance of all of all three phases (poles) of all breakers.2. Inspection of draw out contacts, finger, springs etc and replacement if required.3. Inspection of all limit switch, Gas pressure healthiness of all 03 poles.

4. Cleaning & lubrication of spring charging mechanism.5. Breaker Alignment with bus bar & bottom fixed contacts.6. Manual / electrical operation checking for spring charging close & open.7. Final value of contact resistance of 03 Poles of Ckt breaker.

1. L.T boards C & D.

2. BUMCC, TGMCC, Boiler House MCC, Turbine House MCC, Instrument Com. MCC.

1. Meggaring of board for IR value before staring of overhauling.2. Busbar compartment opening & cleaning with air blowers & markin cloth.3. Inspection of bus bar joints, terminations insulators and fixed contacts, tightness of control wires.4. Boxing up the board.5. Meggering the board after overhauling.6. Overhauling of CENTRIFUGE PUMP LCC, AC oil Pump LCC, Scrapper Con. & clinker grinder MCC,

Densoveyor Comp. MCC.7. Overhauling of all EPB's Stations.

1. Checking & cleaning of jaw contacts of LT breakers.

2. Inspection of O/L relays.3. Inspection of main & arcing contacts.4. Lubrication of spring charging mechanism.5. Cleaning of area chutes.6. Cleaning of secondary fixed & engaging contacts.7. Tightening of control wiring terminations.8. Checking of breaker operation & indications.

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1. Checking & calibration of over load relays.2. Inspection of Main switches, Fuse Carrier Bridge, fuse bases, and fuse carriers.3. Inspection of control & power terminals.4. Inspection / Replacement of contactors kits if required.5. Assembly with calibrated O/L relays.6. Checking of healthiness of all indicating lamps.

1. Leakage test to be carried out throughout the Hydrogen system before Co2 purging.Disconnecting of the slip ring cables, Removal of brush rocker cover/assembly. Cutting /Polishing oslip rings.Decoupling of Main Exciter & removal of main exciter from its foundation.

4. Removal of all gas coolers, cleaning of gas coolers tubs, hydro jet cleaning, hydraulic test of each

cooler, painting of cooler, cleaning of gas cooler ducts.5. Hydraulic test of Gas cooler tubes to be tested at 4 Kg per sq meter for one hour.6. Erection/placement of all gas cooler after O/H.7. Brush gear cable reconnection & assembly of brush gear to be done after O/H.8. All seal oil and lube oil pipe lines of Gen. bearings to be removed and refitted after O/H.9. T/E & E/E seal body & seal linear to be removed and Reassembly after O/H.10. Improvement of Pedestal insulation resistance.11. T/E & E/E seal rings clearance correction after checking & clearance adjusted.

12. T/E & E/E end shields and fan shields were removed all clearances were recorded.13. All rotor fan blade to be removed & fix after O/H14. Generator Rotor thread out, checking of air gap, alignment, bearing clearances etc. to be recorded

before removal of Rotor.15. Hydraulic test of Gen. stator winding at 4 Kg per sq. CM was done.16. Pneumatic test of stator winding was done at 4 Kg. Per sq cm.17. Wedge tightness of entire stator winding & re-wedging of loose wedges, tightness of overhang win

support brackets, through cleaning of Generator internals, casing and stator winding.18. Checking/changing of RTDs.19. Dismantling of all the Phase and Neutral terminal Bushing. All gasket of Terminal Bushing to be

replaced after through cleaning and high voltage test of the terminal bushings.20. Dismantling of Stator terminal Bushing and replacement of all gaskets of Stator water Bushing.21. Dry out of the Generator stator winding by air purging/blowing and by induction heating to be don

Dry out of Rotor to be done.22. ELCID Test and Core Flux test of stator core to be done.

23. RSO test of Rotor winding was done.24. Purge test of Rotor ventilating cannel and retaining ring ventilating cannel to be done.25. Improvement of IR value & PI value of stator winding26. Tan Delta & Capacitance test of Gen. stator winding27. Partial discharge test of Gen. stator winding28. Dry out of stator winding & Glue injection of stator over hang winding and Varnishing of stator

winding.29. Dismantling and reconnection of Gen. Phase & Neutral connection30. Servicing of all hydrogen gas valves, replacement of all flange gasket, valve gasket of seal oil&

hydrogen line for the entire system. Replacement of V/V"s Teflon sheet and erection of new valve

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per requirement.31. Servicing of hydrogen drier32. Servicing of seal oil tank, damper tank, ILI33. Servicing of DPR & POR34. Servicing of stator water filters, seal oil filters.35. Servicing of stator water coolers36. Gen. Bus duct support insulator to be removed and cleaned. Bus duct covers gasket replacement

sealing by putty.37. Measurement of IR value of all seal oil & lube oil pipe & recording the result. All insulating gaskets

were replaced.38. Air tightness test of Generator and complete system to be carried out and immediate re arresting o

any leakage.39. Ultrasonic test of Retaining ring to be done.40. DPT of Retaining ring of rotor to be done.41. Measurement of IR Value, winding resistance and impedance of rotor were measured & recorded42. Rotor to be threaded in as per NTPC instruction.43. Reassembly of T/E & E/E End & Fan shields.44. Reassembly of seal rings, seal covers, and seal body to be done.45. Assembly of seal oil & lub oil pipe lines to be done.

46. Seal oil & lub oil, gas cooler drain pipelines slope to be checked and rectification.47. Painting of Generator and Main Exciter to be done.48. Gas cooler vent lines cleaning.49. Air tightness test of Generator & its gas system pipe lines and all other components of gas system

after final assembly to be carried out.

Cleaning of Generator Protection & Control Panels

Generator, Generator Transformer, UAT

6.6 KV Buses- A & B (unit) Feeders

0.4 KV LT Buses C & D (Unit) Feeders

Generator& UAT CTs Primary injection,

Measurement of IR Value

Capacity test of Station Battery set,

Cleaning of DCDB,

IR Value measurement Tan Delta measurement of HV Bushing & Winding,

Winding resistance measurement,

Impedance Measurement

IR value measurement for Stage # 1 Generator only,

Tan delta and capacitance measurement,

Winding Resistance measurement.

Cleaning of Excitation Transformer,28


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Checking and cleaning of Excitation panel,

Dummy load test9. Cleaning & checking of seal oil & stator water (applicable for # 4 & 5)10. Checking and cleaning of DC lube oil Pump panel11. Servicing of speeder gear motor,12. Cleaning and checking of Barring gear control cubicle,13 DC sequence checking of Generator & UAT protection & control system,14 Checking of Field Breaker, 220 KV ABCB closing/tripping circuit and their interlock.

a. General cleaning of the transformer.b. Attending of oil leakages by replacing the gaskets, O rings etc.

c. Inspection LV, HV connections, cleaning and tightening.d. Over hauling of fan motors which include replacement of bearing, greasing etc and

overhauling of pump motors on need basis.e. Inspection/replacement of cooling circuit connections, over load relays etc.f. Checking of Buchholz Relay operation.g. OTI, WTI calibration

h. Emulsifier system checking on AUTOi. Transformer oil filtration to achieve required parameters.j. Electrical tests of the transformer.k. Painting of transformer outer surface after proper cleaning.

1. Inspection /tightness of HV/LV connections of the transformer after attending oil leakage (ifany) by replacing oil seal/gasket.

2. Inspection of diverter switch of UATs ( applicable for UAT 4A,4B,5A & 5B)3. Attending of transformer oil leakage.4. Cleaning of the transformer outer surface.5. Calibration of OTI, WTI, operation of Buchholz relay.6. Oil filtration to achieve the required parameters.7. Operation of Emulsifier system on AUTO.8. Painting of the transformer after proper cleaning of the transformer

Preventive maintenance of Breaker which includes :-

1. Checking of air leakage/attending.2. Tightness of control wires

3. Recording the timings, contact resistance of the Breaker.4. Checking of Pr. Switch settings.5. Cleaning of Marshalling box and checking the tightness of control wires.6. Recording IR value of the Breaker.

1. Cleaning & tightness of connectors2. Checking of oil level in the bellow and oil leakage (if any)3. CT wire tightening

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4. Recording IR Value.

1. Attending of Hot spots (wherever possible) by replacing /connector tightening2. Cleaning of marshalling boxes and tightening of control wires.3. Cleaning of isolators (wherever possible)

NOTE: Breaker overhauling is done if it is due.

1. MDB inspection, cleaning & tightening done.2. Hopper heater/Rapping motor MCC checked.3. Heaters Junction boxes checked. Worn out components replaced.4. P.M. of Rapping motors & their push buttons carried out.5. Inspection,cleaning, T.B. tightening,replacing defective components

of electronic control panels, carried out.

6. HT/LT CONNECTION of rectifier transformer checked includingre-lugging,retapping etc.

7. Checking & arresting oil leakage from HT/LT BUSHINGS ofrectifier transformers carried out.

8. Marshlling boxes checked including checking of voltage and currentfeed back. Bucholz relay connection checked. Silica gel replaced.

9. HT Knife switches checked & replaced wherever required.10. HT SIDE EARTHING checked/tightened.

11. Control Panels tuned after availability of supply.12. No load/Air load test performed.

1. Soot Blower MCC checked including soot blower feeder inspection, cleaning, tightening anddefective components replacement.2. P.M. of transverse & rotary motors including APH soot blowers motors.3. Local control boxes checking, & replacement of worn out components. Rewiring of limitswitches if required.4. Local Push Buttons checked & replaced wherever required.

1. UCB,VDDC & site panels cleaning

2. Removing connections of valves/dampers

3. Servicing of Actuators

4. Commissioning of valves & dampers

5. Annunciation system checking

6. Removal of defective lamps holders/lamps

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7. Unit & aux protection & interlock checking

8. DCS Checking

9. SOE Checking

10. UPS checking.

1. Removal of connection of valves/dampers

2. Servicing of Bernard Actuators

3. Commissioning of valves/dampers

4. ACS bin cleaning

5. Transmitter calibration

6. Auto loop checking

7. VFD system checking

1. Igniter assembly removing, servicing, commissioning

2. Igniter horn cleaning

3. Scanner assembly, servicing, guide pipe checking

4. HOTV,IOTV checking

5. All hydra motor valves checking

6. All pressure gauge calibration/ checking

7. HAG power cylinder servicing/checking

8. FSSS panel cleaning

9. Replacement of defective relays

10. Simulation checking of FSSS

1. Servicing/cleaning of oil tanks/JBs

2. Checking of all Sulzer valves

1. Removal of primary/ secondary instrument

2. Inst servicing/calibration

3. Removal of pr/temp gauges

4. Pr gauge/temp gauge calibration

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5. Generator RTDs checking

6. Turbine lub oil relay/vacuum relay/furnace switch cal.

7. Cal of BFP,ID/FD/PA AC, DC, seal oil pr switches

8. Inst isolation valve servicing/replacement

9. Site JB cleaning

10. Transmitter calibration

11. Inst commissioning

1. Solenoid servicing

2. Cylinder servicing

1. TSI recorder/ indicator servicing

2. Module cleaning of ECIL panel

3. System checking

1. Servicing & cal of CO system.

2. Servicing & cal of O2 system

3. Servicing & cal of Dissolved O2 system.

4. Servicing & cal of Conductivity system.

5. Servicing & cal of SW resistivity system.6. Servicing & cal of pH system.

7. Servicing & cal of Hydrazine analyzer.

8. Servicing & cal of silica system

9. Servicing & cal of H2 purity system.

10. Commissioning of inst

11. Servicing of SWAS

Fan Gear box1. CT fan gearbox, backlash checking2. CT gearbox internal inspection3. Oil seals replacement4. Gear box oil replacement5. Checking of Foundation bolts and beam healthiness

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6. Fan blades cleaning with soap etc7. Gearbox motor alignment

CT Internals1. Nozzle cleaning and replacement of damaged nozzles to be done2. Drift eliminator and PVC fills cleaning3. Damaged fills replacement4. Damaged drift eliminators replacement5. Cold water basin cleaning6. Structure algae removal7. Any vegetarian growth near CT which obstructs air flow to be cleared.8. Painting of corroded pipes9. Riser valves servicing.

Plant Betterment plans (Modifications & R&M)

Pending defects & PM jobs

Corrective action plans arising out of trip analysis, BTL analysis, Failurediagnostics and other technical audits

KNOWLEDGE TEAM RECOMMENDATIONS

1. Inspection of all vents and drains to be done after removing insulation for signsof external corrosion.2. Revival of all the existing thermocouples inside pent house.3. During revival of Economizer coils, alignment is to be ensured & all the foreignmaterial lying between the coils to be removed.4. Thickness survey to be done (after grinding) on Economizer coils and tubes to bereplaced based on thickness survey.5. Grafting of new plate to be done wherever erosion has taken place at APH inlet.

5,86,89,516 9,02,46,807 14,09,32,085

47,74,430 1,90,15,203 2,37,89,633

1,29,66,988 1,81,57,192 3,11,24,180

33,69,967 2,35,50,557 2,69,20,524

33,93,836 1,75,25,805 2,09,19,641

1,40,40,985 6,54,54,331 7,94,95,316

Documents

#5 Scope of Work