Various Preventive and Maintenance works on Main Boiler and Pressure Part of Unit 7 CTPS like attending leakages round the clock routine, preventive and break down maintenance works cleaning and associated works and De scaling of Pressure Parts

Amount

Attending the leakages of water wall tubes in boiler furnace from down comer / ring header to 40 meter including burner Zone.

Attending tube leakage up to Ist ten H.P. weld joints. (Irrespective of number H.P. weld joints in one frequency). Completion time will be Reckoned after 12 hrs of boiler boxed up and installation of sky climber. (Completion period-12hr for each frequency)

Attending tube leakages for each H.P. weld joints beyond 10Nos. of H.P. weld joint. (Completion period-45 minutes)

Attending the leakages from economizer / LTSH tube.

Attending tube leakage up to Ist ten H.P. weld joints.(irrespective of number H.P. weld joints in one frequency. (Completion period-12 hr for each frequency)

Attending tube leakages for each H.P. weld joints beyond 10Nos. of H.P. weld joint. (Completion period-45minutes)

Attending the leakages in ceiling super heater tubes situated in furnace top before platen super heater, platen super heater tubes.

Attending tube leakage up to Ist ten H.P. weld joints.(irrespective of number H.P. weld joints in one frequency). Completion time will be Reckoned after 12 hrs of boiler boxed up and installation of sky climber. (Completion period-12 hr for each frequency)

Attending tube leakages for each H.P. weld joints beyond 10 Nos. of H.P. weld joint. (Completion period-45 minutes)

Attending the leakages in cold reheat & HRH tubes, Arch Tubes, screen tubes, water wall hanger tubes, super heater hanger tubes, final super heater, exit super heater tubes, extended water wall tubes, ceiling super heater tubes beyond platen super heater.

Attending tube leakage up to Ist ten H.P. weld joints (irrespective of number H.P. weld joints in one frequency). (Completion time will be Reckoned after 12 hrs of boiler boxed up. Completion period-12 hr for each frequency)

Attending tube leakages for each H.P. weld joints beyond 10 Nos. of H.P. weld joint. (Completion period-45 minutes)

Attending the leakages from SCW super heater tubes and extended super heater tubes.

Attending tube leakage up to Ist ten H.P. weld joints (irrespective of number H.P. weld joints in one frequency). Completion time will be Reckoned after 12 hrs of boiler boxed up and installation of sky climber. (Completion period-12 hr for each frequency)

Attending tube leakages for each H.P. weld joints beyond 10 Nos. of H.P. weld joint. (Completion period-45 minutes)

Attending the leakages of hand hole plates of different pressure part header by removing hand hole plates with hand hole cutting equipment, rewelding of the same after complete preparations and stress relieving of the same after welding if required. Rate should be coated on as per joint basis. (Completion period-04hrs)

Attending the leakages of header stubs up to Ist ten stubs joints in one frequency of different pressure parts headers of boiler. Completion Time is given considering pre heating and stress relieving. Completion period-36hrs

Removal of damaged clamps / binders /scallop bars etc and replacement / refitting of the same with new / repaired one in different zones of the pressure parts. The rates should be quoted on as per no. basis as under:-

U’ Clamps. (Completion period-01hr)

Scallop bars. (Completion period-01hr)

Binders, support band, lugs. (Completion period-01hr)

Flexible Connectors (male / female). (Completion period-01hrs)

Fabrication of Hot bends of various degrees and radius of curvature from straight pressure parts tubes by filling sand and heating gas to required temperature of following materials:-

Carbon Steel. (Completion period-04hrs)

Alloy Steel. (Completion period-04hrs)

Stitch Welding of fins of water / steam cool wall for securing of respective positions of tubes. (Completion period-01hrs)

Rectification / replacement of Ash Protector / Shielding / Cassette baffles found damaged / eroded / dislocated or providing new protector in the following pressure part zones( Rates should be quoted on as per no. basis)

Tubular (half round) protector of platen super heater / Reheater inlet etc and their spacer tubes. Protector /shielding shall be rectified / installed with the help of sky climber if available. (Completion period-01hr)

Rectification / replacement of box type protector / cassette baffles found damaged / eroded / dislocated in LTSH / Economizer etc. (Completion period-01hr)

Tubular protectors / shielding of water wall hanger tubes / water wall screen tubes / final super heater / LTSH / economizer / reheater etc. Protector / shielding shall be rectified / installed with the help of scaffolding to be erected by agency as per requirements. (Completion period-15minutes)

Rectification / replacement of box type protector / cassette baffles found damaged / eroded / dislocated of water wall hanger tubes / water wall screen tubes / final super heater / reheater etc. Protector / shielding shall be rectified / installed with the help of scaffolding to be erected by agency as per requirements. (Completion period-02hrs)

Erection of Scaffolding and platform in the following areas:-

Economizer hopper (above). (Completion period-01hr)

S-Panel & bottom ash hopper. (Completion period-04hrs)

Reheater inlet & outlet. (Completion period-04hrs)

Water wall screen tube / final super heater / super heater screen tube/LTSH upper bank to BP upper rear wall. (Completion period-02hrs)

Build up of eroded portion of the tubes caused by ash / steam erosion using suitable welding electrodes matching with parent metal composition. Depth of erosion up to 2.5mm, length of erosion up to 250 mm. (Completion period-01hr)

Lifting and taking out the complete coils in pair of LTSH horizontal coils (upper or lower) after cutting clamps supports, clits, stoppers and releasing from subsequent headers and coil & their restoration after placement of coil. (Completion period-16hrs)

Lifting and taking out the complete coils of Economizer (upper or lower) after cutting clamps supports , clits, stoppers and releasing from subsequent headers and coil & their restoration after placement of coil. (Completion period-16hrs)

Replacement of eroded / damaged tubes / bends of pressure parts in different zones of boiler during preventive maintenance as per procedure mentioned in annexure of the following:-

Carbon / low alloy (T-11) joint. (Completion period-02hrs)

High alloy (T-22) joint. (Completion period-02hrs)

Stainless Steel Joint. (Completion period-02hrs)

Cutting and removal of skin casing / high crown plate by grinder and welding the same with suitable electrode by High pressure welding method, after completion of repair jobs of pressure parts if any.

Thickness -up to 15 mm. (Completion period-01hr)

Thickness-16mm or above. (Completion period-01hr)

Rectification of Buck Stay / Putting buck stay pin on its position in second pass of Boiler / corner No-1, 2, 3 & 4. (Completion period-04hrs)

Round the clock Routine and Preventive Maintenance work of Boiler including oil gun cleaning, valves gland tightening, Coal pipe leakage attending and other minor welding work on main boiler of Unit #7 (120 MW) HTPS Aligarh. (Completion period-Round the clock shift of 8 hours each)

Various cleaning work on Boiler of Unit no-7 (120 MW).

Cleaning / water washing of boiler zero meter floor except bottom ash, economizer hopper etc. (Completion period-08 hrs General shift)

Cleaning of different floors of boiler. (All ducts, structures and other external surfaces). (Completion period-08 hrs General shift)

Cleaning of all valves and skids of firing floor. (Completion period-08 hrs General shift)

Cleaning/water washing of penthouse after opening man holes. (Completion period-06 hrs)

Cleaning/water washing of Goose neck area after opening man holes. (Completion period-04 hrs)

Cleaning of boiler II nd pass (internal). (Completion period-08 hrs)

Cleaning of boiler S-panel (internal).Completion period-02 hrs

Cleaning of wind box L&R (internal). (Completion period-02 hrs)

Various breakdown maintenance work on Boiler of Unit no-7 (120 MW).

Repairing of Man holes. (Completion period-04 hrs)

Repairing of peep holes. (Completion period-02 hrs)

Servicing/replacement of spring hangers, support hangers, anchors and resetting of cold setting values. (Completion period-04 hrs)

Replacement of coal nozzle assembly (coal nozzle and adjacent coal nozzle tip/seal plate) with new repaired one. (Completion period-12 hrs)

Repairing /servicing of burner tilting lever. (Completion period-04 hrs)

Rectification of Buck stays in first and second pass. (Completion period-12 hrs)

Erection of scaffolding from S panel (4 meter level) to burner level i.e. up to 19 meter and providing platform to facilitate inspection / Repairing / replacement of Coal burner tips etc of four tier at all four corner (1,2,3&4) of boiler furnace and dismantling the same after completion of work. (Completion period- 24 hours for Erection of scaffolding and 12 hours for dismantling of scaffolding)

Checking of all four corner Coal burner tips, oil burner tips, air nozzle tips, flame scanner position. (Completion period-08 hrs)

Repairing of coal burner tip/Oil burner tip in installed condition inside the boiler during S/D. (Completion period-08 hrs)

Removing chocking of coal pipe whenever any coal pipe found chocked. One coal pipe of any mill make one job. (Completion period-08 hrs)

Fixing of sky climber in boiler furnace after making proper platform on bottom ash hopper, its operation during execution of the works and dismantling and removal of ash hopper platform after completion of the jobs. Rates should be quoted on as per job basis. (Completion period-08 hrs, This time will be reckoned after cooling of boiler

Shifting of sky climber in boiler furnace at different locations for attending and inspection of various pressure parts zones. Rates should be quoted on as per job basis. (Completion period-04hrs)

Replacement/repairing of eroded flaps of various flue gas damper made out of 3.15mm thick MS sheet/ or plate. MS sheet/ plate to be provided by the department free of cost. (Completion period-08 hrs)

Fabrication of semicircular baffle out of 6mm or available plates & installation of the same in the ducts connection APH outlets to ESP inlets. (Completion period-08 hrs)

Welding of various ducts with arc welding to arrest leakage of air/gas. (Completion period-30minutes)

Servicing / Repairing / Replacement of gun guide assembly at AB and CD elevation. (Completion period-08 hrs)

Servicing of Secondary air damper in wind box (L&R). (Completion period-01 hrs)

Repairing/servicing of scanner guide assembly. (Completion period-08hrs)

Repairing / Replacement of bracing of flue gas duct assembly. (Completion period-04hrs)

Repairing work of coal nozzle when the same is lying outside. (Completion period-24 hrs)

Replacement/Servicing of igniter guide assembly at AB and CD elevation. (Completion period-08hrs)

Repairing/Fabrication of adjustable coal nozzle tips by replacing complete fuel compartment consisting of splitter pates with necessary hard facing and repairing of external housing using stainless steel confirming to AISI-304. (Completion period-48hrs)

Replacement of pipe of Diameter 10mm to 40mm. (Completion period-01hrs)

Attending minor leakage from pipe, bend, etc at different places/location of Boiler side from "0"meter to pent house of boiler. (Completion period)

Replacement of (damaged) Gasket of manhole of boiler drum with new one. (Completion period-24hrs)

Replacement of manhole of boiler drum with new one /repaired /with other boiler drum manhole. (Completion period-30hrs)

Replacement of Phosphate dozing pump with new / serviced one. (Completion period-4hrs)

Servicing of Phosphate dozing pump. Completion period-8hrs

Alignment of Phosphate dozing pump with motor of Unit no-7. (Completion period-01hr)

De-scaling of pressure parts & removal of soot from heating surface of boiler by steam blowing through wall blower/ long retractable soot blower (LRSB) from local/UCB panel of boiler of unit no-7.

Complete servicing/ repairing/ replacement of jammed/ damaged wall blower of unit no-7 for smooth operation as and when required.

Complete servicing/ repairing/replacement of jammed / damaged long retractable soot blower (LRSB) of unit no-7 for smooth operation as and when required.

Complete servicing/ repairing/ replacement of steam valves of wall blower and LRSB's of unit no-7 as and when required.

Akash Engineering Company