Repair Rectification and attending Boiler tube leakage shielding of pressure parts tubes in 2nd pass of Boiler and other miscellaneous works of main Boiler of Unit 4 and 5 2X500 MW BTPS Anpara

Amount

Repair/Rectification of Economizer coil (Upper/Lower).

When the work involves 1 to 10 joints.

When the work involves the number of joints above 10 joints.

Repair/Rectification of Primary super heater coil (LTSH).

When the work involves 1 to 10 joints.

When the work involves the number of joints above 10 joints.

Lifting and taking out the complete coil in pair of Primary super heater Horizontal coil/Economizer coil after cutting of clamps, supports clit, stoppers and releasing from subsequent headers, their restoration and positioning after repair/replacement of coil.

Repair/Rectification of Back Pass Rear/Front/Side wall tube (steam cooled wall tube) of pressure parts tube for rectification of defects if any.

When the work involves 1 to10 joints.

When the work involves the number of joints above 10 joints.

Repair/Rectification of Header stubs of various headers of pressure parts.

When the work involves 1 to 10 joints.

When the work involves the number of joints above 10 joints.

Build-up of eroded portion of pressure parts tube caused by Ash/Steam erosion using suitable electrodes matching with parent metal composition by Arc/Argon welding of 250mm length, 35mm width.

Rectification/Replacement of ash Protector/ shielding/cassette baffles found damaged/ eroded/distorted or providing new protectors in the following pressure parts zone of the boiler:

Tubular protectors/shielding of primary super heater vertical & horizontal, economizer coils. For installation of protectors necessary scaffolding has to be made by the agency.

Box type protectors/ shielding of primary super heater vertical & horizontal, economizer coils. For installation of protectors necessary scaffolding has to be made by the agency.

Fin welding to back pass front side and rear steam cooled wall tubes by high pressure welding.

Rectification/Replacement of damaged hanger strip of economizer coils after cutting of damaged portion by cut rods, grinding of hanger support plate and welding of new/ rectified hanger strip by SS welding electrodes.

Erection of scaffolding and making approaches for checking of pressure parts tubes for rectification of defects if any in the following areas/Zones and dismantling after completion of work.

Super heater/W.W. Screen tube/primary super heater vertical panels/Economizer hanger tubes/economizer inlet header at left and right side in single layer/elevation.

Super heater/W.W. Screen tube/primary super heater vertical panels/Economizer hanger tubes/economizer inlet header from left to right side in single layer/elevation.

Servicing/Revisioning of boiler circulation pump inlet gate valve (manually operated), Nb-500 mm Np- 210 Kg/Cm² . The work shall be carried out as under: (a) Removal of bonnet and yoke of valve after opening the bonnet flange. (b) Taking out the valve Disc safely by opening nuts and bolts. (c) Removal of gland packing & gland bush. (d) Removal of self sealing ring and valve drum after opening the bolts. (e) Servicing/revisioning of valve & perfect lapping of seat and disc to a degree of mirror finish to avoid passing. (f) Cleaning of all components properly. (g) Reassembling of valve after replacement of damaged components and replacement of gland packings. (h) Checking & commissioning of valve for smooth operation and adjustment of spindle for full opening and closing.

Servicing/Revisioning of electrically operated boiler circulation pump discharge valve. Type- Elbow down stop valve. Nb-500 mm Np- 210 Kg/Cm² . The work shall be carried out as under: (a) Removal of bonnet and yoke of valve after opening the bonnet flange. (b) Taking out the valve Disc safely by opening nuts and bolts. (c) Removal of gland packing & gland bush. (d) Removal of self sealing ring and valve drum after opening the bolts. (e) Servicing/revisioning of valve & perfect lapping of seat and disc to a degree of mirror finish to avoid passing. (f) Cleaning of all components properly. (g) Reassembling of valve after replacement of damaged components and replacement of gland packings. (h) commissioning of valve after reassembling & checking its electrical operation for smooth and trouble free opening and closing.

Servicing/Revisioning of manually main steam stop valve. Nb-425 mm, Np- 189.5 Kg/Cm². The work shall be carried out as at Sl. No. 11(a) to 11(h)

Servicing/Revisioning of Economizer inlet isolating gate valve. Nb-500 mm, Np- 302 Kg/Cm². The work shall be carried out as at Sl. No. 11(a) to 11(h)

Servicing/Revisioning of Economizer swing check valve. Nb-500 mm, Np- 302 Kg/Cm². The work shall be carried out as at Sl. No. 11(a) to 11(h)

Servicing/Revisioning of Economizer isolating gate valve & check valve of boiler fill pump line. Nb-200 mm, Np- 221 Kg/Cm². The work shall be carried out as at Sl. No. 11(a) to 11(h)

Servicing/Revisioning of hand operated isolating gate valve & check valve of Primary & Secondary super heater attemperation line & isolating gate valve of Aux. steam line and other similar valves. Nb-150 mm, Np- 224 Kg/Cm². The work shall be carried out as at Sl. No. 11(a) to 11(h)

Servicing/Revisioning of electrically operated isolating gate valve of Primary & Secondary super heater attemparation line & Aux. steam inlet gate valves and other similar valves. Nb-150 mm, Np- 224 Kg/Cm². The work shall be carried out as at Sl. No. 12(a) to 12(h)

Servicing/Revisioning of Motor operated Control valves of Primary & Secondary super heater attemparation line & other similar valves. Nb-150 mm, Np- 224 Kg/Cm² The work shall be carried out as at Sl. No. 12(a) to 12(h).

Servicing/Revisioning of Motor operated Control valves of Re-heater attemparation line & other similar valves. Nb-100 mm, Np- 152 Kg/Cm². The work shall be carried out as at Sl. No. 12(a) to 12(h)

Servicing/Revisioning of Hand operated isolating gate valve of Re-heater attemparation line & other similar valves. Nb-100 mm, Np- 152 Kg/Cm². The work shall be carried out as at Sl. No. 11(a) to 11(h)

Servicing/Revisioning of Motor operated isolating gate valve of Re-heater attempration line & other similar valves. Nb-100 mm, Np- 152 Kg/Cm². The work shall be carried out as at Sl. No. 12(a) to 12(h)

Servicing/Revisioning of Hand operated gate valve of Aux. steam header inlet line & other similar valves. Nb-400 mm, Np- 205 Kg/Cm². The work shall be carried out as at Sl. No. 11(a) to 11(h)

Servicing/Revisioning of outlet check valve of Aux. steam line & other similar valves. Nb-400 mm, Np- 205 Kg/Cm². The work shall be carried out as at Sl. No. 11(a) to 11(h)

Servicing/Revisioning of Hand operated High pressure valves and NRVs. Nb-15 to 100 mm. The work shall be carried out as at Sl. No. 11(a) to 11(h)

Servicing/Revisioning of Motor operated High pressure valves. Nb-25 to 100 mm. The work shall be carried out as at Sl. No. 12(a) to 12(h)

Servicing/Revisioning of Motor operated High pressure valves. Nb-150 to 250 mm. The work shall be carried out as at Sl. No. 12(a) to 12(h)

Servicing/Revisioning of Hand operated High pressure valves. Nb-150 to 250 mm. The work shall be carried out as at Sl. No. 11(a) to 11(h)

Servicing/Revisioning of Check valves Re-heater isolating device. Nb-700mm/ 900mm. The work shall be carried out as at Sl. No. 11(a) to 11(h)

Servicing/Revisioning of Motor operated High pressure valves. Nb-250 to 350 mm. The work shall be carried out as at Sl. No. 12(a) to 12(h)

Servicing/Revisioning of Hand operated High pressure valves. Nb-250 to 350 mm. The work shall be carried out as at Sl. No. 11(a) to 11(h)

Servicing/Revisioning of Boiler Drum safety valves. Nb-75mm, Np-205 to 212 Kg/Cm². The work involved are as under: (a) Removal cover and lever mechanism i.e. remove top lever pin and top lever. Loosen cap set screw & drop lever assy. Remove the cotter pin & release collar. Remove the two top yoke nut, the yoke, spring adjusters & lock nut from the assy. after taking proper measurement of height of compression screw. Then lift the spring and spring washer from the spindle. (b) Unscrew the cover studs and lift the spindle, cover plate & disc holder straight out of the safety valve. Remove the disc by unscrewing it from the coarse right hand thread on the spindle and remove the disc holder. (c) The guide & adjusting ring assy. can now be removed from the base by lifting the straight. The position of upper adjusting ring should be marked as under: • Make punch mark in axial line on a tooth of upper adjusting ring and the outside barrel of guide. • Measure the overall height of the guide & upper adjusting assy. and record. • Measure & record the height from the valve bushing seat to the recess in the hose where the guide normally rests. This is mandatory & important for determining the amount of metal removed from the seat. • Mark the lower ring in the line with lower ring pin. Now place a straight edge or ring lap across the top of the seat & count the number of notches that the ring is below the seat and record it. (d) Servicing/revisioning of safety valve & perfect lapping & blue matching of seat and disc to avoid passing. (e) Repairing/Replacement of damaged parts if necessary. (f) Reassembling of various components of safety valve. (g) Proper adjustment & resetting of spring & nozzles by tightening and unscrewing the nut for getting required floating pressure. (h) Placement of lever mechanism and cover for normal operation of safety valve.

Servicing/Revisioning of Super heater outlet safety valves. Nb-75mm, Np-187.5 Kg/Cm². The work shall be carried out as at Sl. No.32(a) to 32(h)

Servicing/Revisioning of Electromagnetic relief valves. Nb-50mm, Np-184 Kg/Cm². Temp.-548ºC. The work shall be carried out as under: (a) Dismantling of pilot valve. (b) Cleaning and perfect lapping of seat of pilot valve. (c) Dismantling of disc holder of safety valve, cleaning and perfect lapping of disc. (d) Reassembly of various components of safety valve. (e) Commissioning & final setting of safety valve for smooth operation.

Servicing/Revisioning of hot Re-heat & Cold Re-heat safety valves. (a) CRH- Nb-150mm, Np-50 Kg/Cm². (b) HRH- Nb-150mm, Np-46.5 Kg/Cm². The work shall be carried out as at Sl. No. 32(a) to 32(h)

Servicing/Revisioning of continuous blow down tank safety valve. Nb-150mm, Np-16Kg/Cm². The work shall be carried out as at Sl. No. 32(a) to 32(h)

Servicing/Revisioning of Auxiliary PRDS line safety valves. Nb-65mm, Np-20Kg/Cm². The work shall be carried out as at Sl. No. 32(a) to 32(h)

Servicing/Revisioning of Soot blowing line safety valve. Nb-150/200mm, Np-25Kg/Cm². The work shall be carried out as at Sl. No. 32(a) to 32(h)

Servicing/Revisioning of pneumatic operated control valve/block valves. Nb-50 to 100mm.

Servicing/Revisioning of pneumatic operated piston valves of primary & secondary super heater attemperation line. Nb-200mm, Np- 205 Kg/Cm².

Servicing/Revisioning of hand operated valves and NRVs of oil control station at firing floor. Nb-25 to 150mm.

Replacement of gaskets of flanges and bonnets of valves.

Replacement of gland packing of high pressure valves.

Attending leakage of pipelines and headers etc. of main boiler.

Cleaning of oil strainer of fuel oil station on firing floor.

Servicing of gear box of hand operated air motor driven valves of main steam line, BCP, ERV etc.

Replacement of safety valve seat of critical piping such as boiler drum, main steam line, Re-heater line etc. Scope of work shall be as under: (a) Dismantling and removal of safety valve exhaust pipe, connections and seat drain line. (b) Dismantling and removal of safety valve body by cutting the valve nozzle by grinding. (c) Removal of valve seat from valve. (d) Edge preparation by grinding making J-edge at critical pipe nozzle and valve body. (e) Alignment and fitment of new/repaired safety valve seat. (f) Seal welding of safety valve seat with valve body by IBR approved high pressure welder. (g) Welding of safety valve nozzle with critical piping by IBR approved high pressure welder. (h) Prior to welding, preheating of valve body and critical piping shall be carried out at required temperature. (i) After every three run welding radiography/NDT of H.P. joint shall be carried out. Next run of welding shall be started only after rectification of any defect observed in radiography/NDT. (j) Stress relieving of the valve body, joint and critical piping as per IBR at required temperature. (k) All the welding work shall be carried out only by IBR approved high pressure welder strictly as per IBR norms by sequence welding technique using suitable welding electrodes. (l) Connection of exhaust pipes and seat drain line. (m) Servicing/revisioning of safety valve and its assembly.

Replacement of high pressure valve (motor operated/hand operated) of critical piping of boiler of size 15 - 25 mm. Scope of work shall be as under: (a) Dismantling and removal of valve body by cutting with grinders from main piping joints at both ends. (b) Edge preparation by grinding, making J-edge/V-edge as per requirement at both ends of piping joints and valve body. (c) Alignment and fitting of new/repaired valve keeping in view the correct direction of flow. (d) Welding of valve body with piping on both sides by IBR approved high pressure welder. (e) After welding radiography/NDT of H.P. joint shall be carried out. Any defect observed in radiography/NDT shall be rectified by the contractor free of cost. (f) All the welding work shall be carried out only by IBR approved high pressure welder strictly as per IBR norms by sequence welding technique using suitable welding electrodes. (g) Servicing/revisioning of valve and its assembling.

Replacement of high pressure valve (motor operated/hand operated) of critical piping of boiler of size 40 - 50 mm. Scope of work shall be as under: (a) (a) Dismantling and removal of valve body by cutting with grinders from main piping joints at both ends. (b) Edge preparation by grinding making J-edge/V-edge as per requirement at both ends of piping joints and valve body. (c) Alignment and fitting of new/repaired valve keeping in view the correct direction of flow. (d) Welding of valve body with piping on both sides by IBR approved high pressure welder. (e) After welding radiography/NDT of H.P. joint shall be carried out. Any defect observed in radiography/NDT shall be rectified by the contractor free of cost. (f) All the welding work shall be carried out only by IBR approved high pressure welder strictly as per IBR norms by sequence welding technique using suitable welding electrodes. (g) Servicing/revisioning of valve and its assembling.

Replacement of high pressure valve (motor operated/hand operated) of critical piping such as Main steam, Final super heater, Primary super heater, CBD etc. of size 65 - 150 mm. Scope of work shall be as under: (a) (a) Dismantling and removal of valve body by cutting with grinders from main piping joints at both ends. (b) Edge preparation by grinding making J-edge/V-edge as per requirement at both ends of piping joints and valve body. (c) Alignment and fitting of new/repaired valve keeping in view the correct direction of flow. (d) Welding of valve body with piping on both sides by IBR approved high pressure welder. (e) Prior to welding, preheating of valve body and critical piping shall be carried out at required temperature. (f) After every three run of welding radiography/NDT of H.P. joint shall be carried out. Next run of welding shall be started only after rectification of any defect observed in radiography/NDT. (g) Stress relieving if required of the valve body, joint and critical piping as per IBR at required temperature. (h) All the welding work shall be carried out only by IBR approved high pressure welder strictly as per IBR norms by sequence welding technique using suitable welding electrodes. (i) Servicing/revisioning of valve and its assembling.

Replacement of Coal Nozzle ASSY. Complete of Consisting of Coal Nozzle Casting ,Adjustable Coal Nozzle Tip, Seal Plate, Splitter Plate ,Ribbons by repaired one Scope of work are as follows:- A. Locking of Burner Tilting Mechanism, keeping all Burners at horizontal position (0- 0). Disconnecting the Tilting rod from Tilting Mechanism and clevis bracket. B. Dismantling of Fuel inlet Elbow by opening bolts of Flanged Collars and Victaulic Couplings, taking out from its position prior to dismantling of fuel inlet elbow, fuel piping must be locked properly by providing welded supports. C. Opening of side panels and cutting of Manhole doors at sealing plate of side panel, opening of front panel. D. Fabrication of temporary structure for taking out complete Coal Nozzle Assy. E. Opening of flange and taking out coal Nozzle Assy. from its position. F. Dismantling of Adjustable Coal Nozzle Tip, Seal Plate Splitter Plate Ribbons, set plates etc. from Coal Nozzle Assy. If required. G. Refitting of new/ repaired Coal Nozzle Assy. at its original position and reassembling the tilting lever and locking device. H. Welding of Manhole Plates at sealing plate of side panel and tightening of side and front panel, Victaulic coupling and flanges.

Repairing/ servicing of burner tilting lever. Scope of work are as follows:- a.Opening of wind Box front and side panel plate. b. Dismantling the Tiling Mechanism from Tilting Levers. c. Reassembling the Tilting Mechanism after repairing/servicing when Nozzles are in Horizontal (0-0) position. d. Refitting of Wing Box Side and Front Panels.

Replacement of fuel Inlet elbow. Scope of work are as follows:- a. Opening of Bolts and Nuts of Victaulic Coupling and Flange of Coal Nozzle after locking fuel Piping properly by welding. b. Taking out the fuel Inlet Elbow. c. Re-fixing and aligning the new/Repaired Fuel Inlet Elbow. d. Tightening the nuts and Bolts of Victaulic Coupling and Coal Nozzle Flange after providing gaskets. Removal of locking and supports of respective Fuel piping.

Replacement of Distance piece of Fuel Inlet Elbow. Scope of work are as follows:- a. Opening of Bolts and Nuts of Victaulic Coupling and Flange of Coal Nozzle after locking fuel Piping properly by welding. b. Taking out the Distance piece of fuel Inlet Elbow. c. Re-fixing and aligning the new/Repaired Distance piece. d. Tightening the nuts and Bolts of Victaulic coupling and Coal Nozzle Flange after providing gaskets. Removal of locking and supports of respective Fuel piping.

Servicing / revisioning of Gun Guide Assy. of AB, CD, and EF & GH- Elevations. Scope of work are as follows:- a. Removal of Oil, Steam and Air Hoses from Oil Gun Assy. b. Taking out Gun Guide Assy. after dismantling of front panel and associated equipments. c. Servicing/ revisioning of Gun Guide Assy. d. Refitting of Gun Guide Assy. and connecting all associated equipments.

Servicing/revisioning of Oil Burners of AB, CD, EF, & GH- Elevations Scope of work are as follows:- a. Removal of Oil, Steam and Air Hoses from Oil Gun Assy. b. Taking out Oil Gun Assy. After dismantling of front panel and associated equipments. c. Servicing/ revisioning of Oil Gun Assy. d. Refitting of Oil Gun Assy. and connecting all associated equipment.

Servicing/ revisioning of Igniter Guide pipe Assy. Scope of work are as follows:- a. Opening of front and side panels of Wind Box and cutting of Manhole at sealing of side panel. b. Opening of flange bolts of Igniter Guide pipe Assy. c. Taking out Igniter Guide pipe Assy. d. Servicing/revisioning/ replacement of Igniter Guide pipe Assy. with new/ repaired one and its proper alignment. e. Refitting of front and side panel and welding of sealing plates.

Servicing/ revisioning of Scanner Guide pipe Assy. Scope of work are as follows:- a. Opening of front and side panels of Wind Box and cutting of Manhole at sealing of side panel. b. Opening of flange bolts of Igniter Guide Pipe Assy. c. Taking out Scanner Guide pipe Assy. d. Servicing/ revisioning/ replacement of Scanner Guide Pipe Assy. with new/ repaired one and its proper alignment. e. Refitting of front and side panel and welding of sealing plates.

Repairing/ revisioning of burnt Air compartments.

Servicing of Secondary Air Dampers of Wind Box. Scope of work are as follows:- a. Taking out Hinge pin of Damper Shaft from Power cylinder. b. Servicing of Bush and shaft making its free movement by applying antirust and powder lubricant. c. Reassembling of Damper and connecting Hinge pin with Power Cylinder.

Repairing/ revisioning of Secondary Air Dampers of Wind Box. Scope of work are as follows:- a. Taking out split locking & Hinge pins and bolts of Damper blades b. Dismantling of Damper blades, shaft and bush after cutting of locking bolts and plates. c. Repairing of bent/ damaged shafts and blades. e. Reassembling of Damper blades and shafts & fixing, ensuring smooth operation.

Repairing of Wind Box by welding.

Assembling of Coal Nozzle Assy. and transportation to site at respective elevations. Assembly consists of Coal Nozzle Casting, S.S. Coal Nozzle Tip, Seal plate, Set plates, Ribbons Side Rib plates. Welding of set plates and Side Rib plates by S.S. welding electrodes. During Assembling the required clearance between Coal Nozzle, Seal plate and Coal Nozzle Tip must be ensured for proper tilting.

Arresting of coal leakage from flange of coal burner at an elevation of corners.

Replacement of damaged bolts of burner compartments by cutting the stuffing box and welding of bolt head of required size. Restoration of stuffing box by welding.

Replacement of seal tube of oil burner/igniter/flame scanner hoses.

Servicing/ revisioning of Flue Gas, Primary and Secondary Air Dampers. The work involves following : a. Disconnecting the Damper links by taking out link pins. b. Removal of Gland Bushes and seal packing. Filling of New seal packing and fitting of Gland Bushes. c. Repairing of Gland bushes if found Eroded. d. Servicing of Damper Flaps for free and smooth operation. e. Reassembling of Damper links and commissioning.

Repairing/ replacement of Eroded Flaps of Flue Gas, Primary and Secondary Air Dampers.

Repairing/ replacement of Eroded Stainless Steel Shafts of By-Plane Dampers.

Cleaning of Aerofoil of Secondary Air duct to Wind Box.

Checking and repairing of S.S. Coal Nozzle Tip, Splitter plate of Coal Nozzle Assy. from inside the Furnace (In- situ) and application of refractory if found damaged at Splitter plate.

Inspection of Boiler Drum Internals and rectification of defects observed. D.P. Testing of shell joints to check for any crack and its repair by H.P. welding, when only 10 Nos.Turbo Separators are taken out/ replacement of manhole gasket and its tightening to ensure zero leakage.

Servicing of Spring Hanger supports, Hydraulic supports, Anchors & restraints of Boiler Piping & Ducts and resetting on cold set values.

Repairing of Flue Gas/ Primary/ Secondary air Ducts by providing M.S./ carbon steel plates over eroded portion and welding with suitable electrode.

Welding of various ducts to arrest leakage of Air/ Flue Gas.

Repairing/ replacement of bracing of Flue Gas/ Primary/Secondary air Ducts.

Servicing of Scanner Air Fan.

Fabrication and erection of Temporary Structures at different Floors of 500 MW Boilers.

Repairing/Reclamation of old & used and worn out repairable Coal Nozzle Casting. Works involved are as under : (a) Grinding of Eroded portion of Coal Nozzle Castings, making surface smooth. (b) Filling of Eroded potion of Coal Nozzle Castings by Arc Welding with suitable Welding Electrodes such as Endotherm- CS or equivalent. (c) Cutting of two nos. 12 mm thick M.S. plate by Industrial Cutting Gas of Coal Nozzle Castings. (Approx. Size- 0.5x 1.0 mar.) (d) Making surfaces smooth by grinding. (e) Welding of fresh plate at Left Right, Top/ Bottom of Coal Nozzle Casting all along the fitment place of Ribbon from outside or as required. (f) Hard Facing of Coal Nozzle Casting at inside circular portion near flanged collar by two inch Chequering Pattern using Sequence Welding Technique with suitable Gard Facing Arc Welding Electrodes, such as Bor- C or equivalent. (g) Repairing of damaged Pivot Pin portion of Coal Nozzle Casting. Free movement for coal nozzle Tip and Seal plate must be ensured maintaining proper clearances between Coal Nozzle & Seal plate and Tip & Seal Plate.

Repairing/Reclamation of old & used and worn out repairable Coal Nozzle Tips. Works involved are as under : (a) Dismantling of Splitter Plate, all set plates from worn out Coal Nozzle Tip Assy. by cutting with Cut rods. (b) Removal of damaged/eroded portion of Stainless Steel Coal Nozzle Tip by cutting with Cut rods. (c) Cutting of 10mm thick Stainless Steel plate by cut rods to required size for welding at removed eroded portion of coal nozzle Tip. (d) Making surface smooth and Edge preparation making ‘V’ Edge by Grinding. (e) Welding of fresh plate at Coal Nozzle Tip from inside and outside with suitable S.S. Welding Electrode such as Rutox ‘A’ Stab. or equivalent. (f) Hard Facing of Coal Nozzle Tip at taper portion (Upper & Lower) by two- inch Chequering Pattern using Sequence Welding Technique with suitable Hard Facing S.S. Electrodes. Free movement for Coal Nozzle Tip and Seal Plate must be ensured maintaining proper clearances between Coal Nozzle & seal plate and Tip & Seal Plate.

SHAKSHI ENGINEERING CO.

S. S. ENGINEERING AND CO