Rotor restacking and re-barring of Crompton Greaves make, 800HP, 3.3kV, 750RPM Granulator cooler fan motor of NP Plant, FACT-CD, Ambalamedu.

Rotor restacking and re-barring of Crompton Greaves make, 800HP, 3.3kV, 750RPM Granulator cooler fan motor of NP Plant, FACT-CD, Ambalamedu.

Motor dismantling and stator works: The work includes removing heat exchanger, cooling fan cover and fan, dismantling the motor, threading out the rotor from the stator core pack, inspection of stator/rotor/end overs/bearing cup/wedges and assembling parts, cleaning stator parts and windings, re-insulating damaged insulaions, preheating, varnishing using insulating varnish, curing, fixing new heater coils, wiring heater coils to the terminal block, applying finishing varnishes. Damaged wedges shall be replaced with good quality, glass laminated (or superior) type wedges. The contractor shall arrange new 230V/250W heater coil and thermal insulated wires for successful completion of the work.

Rotor restacking: This work includes, machining the lock welding, shifting the rotor to hydraulic press, removing the core locks, lifting the core one by one with special fixtures, segregating the damaged rotor core from core pack, removing the old burnt core plate varnishes by chemical treatment, cleaning, removing the surface kinks, replacing damaged core stampings with new one, varnishing the stampings in re-varnishing cum conveyor oven to cure the core plate varnish, staggering the core with special tools and machineries, locking and repositioning the core pack to the rotor shaft, welding the locks in hydraulic press, conducting the flux loop test to ascertain the restacked core healthiness, cleaning and polishing the slots ready to feeding. This work shall be executed after analyzing the rotor flux loop test report, visual inspection and after getting approval from concerned engineer in charge.

Rotor rebarring: This work includes mounting the rotor in lathe, machining both side end ring, stripping out all the rotor bars in the bar removing machine using special tools and machineries, machining the new rotor bars & end rings made out of electrical conductivity grade copper, inserting the new rotor bars using special tools and machineries, positioning, locking, machining both side rotor bars for proper bedding of bars and end rings, brazing the bars and end rings using silver brazing rods, flux & oxy-acetylene gas and thermal protection materials, verifying the healthiness of the brazed joints before and after machining the excessive materials, cleaning, dip varnishing the rotor with class ‘F’ varnish, baking, applying finishing varnish to the overhang portions. New copper rotor bars and end rings shall be used for doing this work. The end ring shall be of slotted disc type copper end ring. Rotor bars shall be brazed in to the end ring properly. Vendor shall submit rotor bar and end ring dimensional details to verify before starting the work. This work shall be executed after getting approval from concerned engineer in charge.

Machining rotor, bearing housing and end covers: This work includes inserting sleeves/machining for rotor shaft dimension correction, suiting bearings on end covers, bearing housing, inner grease cups and outer grease cups.

Rotor balancing: The work includes Fixing of inside cooling fan on rotor using new nut/bolt/star washer/spring washer, inserting outer cooling fan/coupling and doing dynamic balancing of rotor to balance quality grade of G2.5 at rated RPM. Anabond thread sealing compound shall be applied to the thread of bolts to avoid loosening due to vibration. This work shall be done after rotor repair work. The test reports shall be submitted.

Fabrication of new cooling fan and hub: The work includes fabrication of new fan hub and cooling fan as per the same dimensions of existing one. This work shall be executed after getting approval from concerned engineer in charge.

Heat exchanger cleaning and painting: This work includes proper cleaning of cooling tubes (both inside and out side) and painting using two coats of anti-corrosive epoxy paint over suitable primer. This work shall be executed on the basis of requirement and after getting approval from concerned engineer in charge.

Assembling, painting and testing of motor: The work includes assembling of motor using the new bearings supplied by FACT(free of cost), painting of motor using two coats of anti-corrosive epoxy paint over suitable primer, conducting routine tests as per relevant IS standers and No-load trial run at the rated voltage of 3.3 KV. All test reports shall be submitted before dispatching the motor. The test results shall be in compliance with applicable standards/ regulations etc. In case of deviations beyond acceptable values, they shall be brought to normal values by carrying out necessary corrective measures without any extra cost to FACT. Mobil Unirex N3 grease shall be used for motor bearing lubrication. Neoprene gaskets shall be provided heat exchanger joining area and fan cover joining area. Contractor shall ensure proper cooling of the motor. Greasing arrangements at both ends with "SS" tubes shall be provided.

GENLINE ELECTRIC (BID ID -3265908)

RAJAMANE AND HEGDE SERVICES PVT LTD (BID ID -3265844)

Delta Roto tech Pvt. Ltd. (BID ID -3266937)