Servicing Revisioning of high pressure valves and Long Retractable Soot Blowers Wall blowers during overhauling of Unit No 5 of 2X500 MW BTPS Anpara

Amount

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. 1(a) to 1(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. 1(a) to 1(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. 1(a) to 1(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. 1(a) to 1(h)

Servicing/Revisioning of hand operated isolating gate valve & check valve of Primary & Secondary super heater atttemparation 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. 1(a) to 1(h)

Servicing/Revisioning of electrically operated isolating gate valve of Primary & Secondary super heater atttemparation 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. 2(a) to 2(h)

Servicing/Revisioning of Motor operated Control valves of Primary & Secondary super heater atttemparation line & other similar valves. Nb-150 mm, Np- 224 Kg/Cm² The work shall be carried out as at Sl. No. 2(a) to 2(h).

Servicing/Revisioning of Motor operated Control valves of Re-heater atttemparation line & other similar valves. Nb-100 mm, Np- 152 Kg/Cm². The work shall be carried out as at Sl. No. 2(a) to 2(h)

Servicing/Revisioning of Hand operated isolating gate valve of Re-heater atttemparation line & other similar valves. Nb-100 mm, Np- 152 Kg/Cm². The work shall be carried out as at Sl. No. 1(a) to 1(h)

Servicing/Revisioning of Motor operated isolating gate valve of Re-heater atttempration line & other similar valves. Nb-100 mm, Np- 152 Kg/Cm². The work shall be carried out as at Sl. No. 2(a) to 2(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. 1(a) to 1(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. 1(a) to 1(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. 1(a) to 1(h)

Servicing/Revisioning of Motor operated High pressure valves. Nb-25 to 100 mm. The work shall be carried out as at Sl. No. 2(a) to 2(h)

Servicing/Revisioning of Motor operated High pressure valves. Nb-150 to 250 mm. The work shall be carried out as at Sl. No. 2(a) to 2(h)

Servicing/Revisioning of Hand operated High pressure valves. Nb-150 to 250 mm. The work shall be carried out as at Sl. No. 1(a) to 1(h)

Servicing/Revisioning of Check valves Re-heater isolating device. Nb-700mm/ 900mm. The work shall be carried out as at Sl. No. 1(a) to 1(h)

Servicing/Revisioning of Motor operated High pressure valves. Nb-250 to 350 mm. The work shall be carried out as at Sl. No. 2(a) to 2(h)

Servicing/Revisioning of Hand operated High pressure valves. Nb-250 to 350 mm. The work shall be carried out as at Sl. No. 1(a) to 1(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.22(a) to 22(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. 22(a) to 22(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. 22(a) to 22(h)

Servicing/Revisioning of Auxiliary PRDS line safety valves. Nb-65mm, Np-20Kg/Cm². The work shall be carried out as at Sl. No. 22(a) to 22(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. 22(a) to 22(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) 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.

Complete overhauling of Long Retractable Soot Blowers (LRSB). Works involved are as under: i. Servicing/overhauling of Traverse/Rotary Gear box. a) Dismantling of Traverse/Rotary Gear box. b) Cleaning of Traverse/Rotary Gear box after draining oil & removing sediments with rustolene/K-oil. c) Replacement of damaged gears if found. d) Reassembling and mounting of Traverse/Rotary Gear box after servicing/overhauling. ii. Replacement/repairing of damaged Trip Rod cover plate/Trip Rod if required by proper grinding and welding with suitable cast iron welding electrode. iii. Servicing/revisioning of chain of Traverse & Rotary motion. a) Removal of chain after opening the chain locks. b) Cleaning of chain by cleaning agent/Trichloroethelene with soft broom and removal of rust if any. c) Applying lubricating oil SAE-30/Servoline-140 over the chain. d) Reassembling and mounting the chain and providing chain locks. e) Proper tensioning of the chain with the help of chain tensioning device. iv. Checking and adjustment of Droop of Lance tube inside the boiler by operating LRSB and setting the same if required. v. Adjusting the blowing pressure at the required value of each LRSB. vi. Commissioning and trial run ensuring smooth operation of the LRSB.

Servicing/overhauling of Carriage Housing Assembly. Works involved are as under: i. Dismantling and opening of Feed Tube from steam valve head assembly. ii. Dismantling of socket cover bush. iii. Removal of Gland packing and seals. iv. Dismantling the Chain sprocket and removal of Carriage Housing Assebly. v. Complete cleaning of carriage housing assembly along with gears by rustolene/K-oil. vi. Replacement of damaged part if any. vii. Reassembly after providing bevelled packing rings, sealing rings and gaskets. viii. Topping up of lubricating oil.

Servicing/overhauling of Soot Blower steam head valve. Works involved are as under: i. Dismantling of soot blower steam head valve. ii. Checking of valve seat, stem, disc & spring tension. iii. Lapping of valve seat & disc and its blue matching. iv. Reassembly after replacement of gland packing if required. v. Remounting of soot blower steam head valve. vi. If any crack is observed on the valve seat, the complete steam head valve to be replaced with new/repaired one.

Complete overhauling of Wall Blowers (Deslaggers). Works involved are as under: i. Servicing/overhauling of Traverse/Rotary Gear box. a) Dismantling of gear boxes of wall blowers. b) Cleaning of gear box after draining lubricating oil & removing deposits & sediments with rustolene/K-oil. c) Replacement of damaged gears parts if any. d) Reassembling and mounting of Gear boxes and their mounting. e) Replacement of damaged gaskets and refilling the lubricating oil to the required level. ii. Setting of Swivel Tube Nozzle by making 25mm gauge, at 38.0 mm inside the furnace from water wall. iii. Adjustment of the blowing pressure at each blower to required value. iv. Testing, commissioning and trial run ensuring smooth operation of the wall blower.

Replacement of bent/damaged Lance Tube/Feed Tube assembly of Long Retractable Soot Blowers (LRSB). Works involved are as under: i. New/required Lance Tube/Feed Tube of length 10 mtr. Approx. And weight 400 kg & 250 kg to be shifted by lifting with winch machine at required elevation and side of the boiler from central store/site store. ii. After dismantling of carriage housing assembly, damaged feed tube to be removed out side from the Lance Tube. iii. Removal of damaged Lance Tube from carriage housing and shifting to the ground floor. iv. Alignment of Lance Tube after fixing in position with carriage housing assembly. v. Checking and adjustment of Droop of Lance Tube inside the boiler by operating LRSB and setting the same if required

Replacement of new/repaired on site damaged swivel tube assembly of Wall Blowers (Deslaggers). Works involved are as under: i. Deassembling and removal of swivel tube from traverse gear box of wall blowers/deslaggers. ii. Fixing, alignment and assembling of new/repaired swivel tube (by welding, grinding etc. During overhauling on site) with traverse gear box assembly. iii. Setting of Swivel Tube Nozzle with 25mm gauge, at 38.0 mm inside the furnace from water wall. iv. Setting and adjustment of forword, rotary and reverse movement of Wall Deslaggers.

M/S POWER ASSOCIATES

M/S BHARAT ENGINEERS AND ERECTORS