MID/AN/101

1. Dismounting of 485 kW, 650 HP BHEL Make HT motor from its place of installation by way of disengaging all its three phase cable connections of rotor, stator, commutator assembly, trifurcated sealing box, etc. Opening & disengaging coupling set (Motor half coupling & Pump-half coupling) of Unit, separating motor from motor skirt by opening all its nuts & bolts and placing motor on steel fabricated stool properly. Complete job. 01Job 2. Extraction of whole pumping unit from its respective pit by way of dismantling, opening all internal and external 500 mm dia. x 200 mm dia. x 70 mm dia. lengths of column assembly components in sequence along with connected fittings such as muff coupling, C.I. Guide spiders, top shaft, stuffing box, C.I. Bell mouth, enlarger, strainer and bowl assembly lubrication system of column assembly one by one and stacking of each at pump house after checking and segregating of damaged defective parts of each. Complete job. 01Job 3. Transportation of the damaged Bowl assembly of the pumping unit from the site to workshop for repairs using manual labour, mechanical transport, mobile crane etc. Back shifting to site LIS Ranjan after repairs, unloading. Complete job. 01Job 4. Dismantling of bowl assembly by way of opening and extraction of 3no. Bowl cases, 3 No. stainless steel impellers from SS impeller (pump) shaft in sequence by removing / disengaging all nuts and bolts, lock rings, back plate of each bowl case with fabricated pullers, heavy duty tools and tackles without damaging of cast iron bowl and SS impeller. Proper stacking of each dismantled parts / component. Complete Job. 01Job 5. Repair of AISI-410-SS close type impeller by way of rebuilding of all worn out portions such as impeller wanes, bore hole and keyways by way of remetalling in layers with suitable SS welding electrodes, then machining, turning, grinding, polishing and finishing of the impeller to true/standard size and specification so as to fit on leaded bronze bearing ring with suitable clearance. The job includes balancing of impeller statically and dynamically. Complete job. 03 Jobs 6. Providing of new cast / fabricated and machined leaded bronze impeller wearing ring in reconditioned seat having proper clearances with the impeller (as per size and specification) Complete Job 03Jobs 7. Repair of AISI-410-SS impeller shaft by way of rebuilding of all worn out and under size portions by way of remetalling in layer with suitable SS welding electrodes, then turning, grinding, polishing and finishing of the impeller shaft to true size and specification. Also straightening and aligning the shaft on hydraulic press, removing of deflections at ends and checking the shaft’s alignment on lathe machine, providing & fitting of new cotter pins/ keys of AISI-410-SS for its proper fitment. (as per size and specification) Complete job.01Job 8. Repair of C.I. Bowl case by way of welding, rebuilding the damaged worn-out portions of internal as well external surfaces of the bowl case with specified welding C.I. electrodes. Job also involves repair, reconditioning of elongated holes of flanged ends, the pump shaft bore hole of bowl after remetalling and turning, finishing it to true size, providing and fitting of new casing studs, Nitrile compressed rubber lined leaded bronze discharge bush in the pump shaft collar groove, providing / fitting S.S. lock plates and washers, fine grinding of bowl case with pencil grinder, rebuilding, turning, finishing to size the seat of the impeller bearing ring in each bowl case and having suitable clearances. Complete job. 02Jobs 9. Complete assembling of the bowl assembly by way of mounting of three no’s AISI-410-SS impellers on 85 mm dia., 2850 mm long pump shaft with three no. bowl cases, one no. enlarger, one no. bell mouth, one no. stiffener in sequences at their respective places with key holding rings, back washers suitable with required allowances. Re-connecting of M.S. strainer to bowl assembly. Complete job in all respects.01Job