Repairs to 250 KVA transformer at LIS Ismailpur along with allied electromechanical works.

Repairs to 250 KVA transformer at LIS Ismailpur along with allied electromechanical works

Disconnecting the 250 KVA electric transformer from the input and output connections, from HT and LT side after ensuring the shutdown from the concern sub division of PDD. Lowering the transformer from the platform and then loading the electric transformer using manual labour & hydra crane in the mechanical transport for shifting it to workshop for repairs. Unloading at workshop and then dismantling the 250 KVA transformer, at workshop by way of extracting out the damaged HT coils & LT coils, LT bushes-03 no., HT bushes-03 no., damaged insulator, rubber gasket, nuts and bolts. Complete rewinding of 3 no. HT leg coil assembly with aluminum wire of appropriate gauge& reconditioning of 3 no. LT leg coils which includes proper insulation. Keeping the coil assembly in the oven to make moisture free so that requisite megger value is achieved. Providing and fitting of LT and HT bush rod sets, new insulator, rubber gasket, new copper nuts and bolts and other necessary items. Cleaning the sump/container of transformer with appropriate chemical agent to remove all carbon deposit. Lowering the assembled coil assembly in the sump of the transformer and then securing it with the body of the transformer. Filling the transformer oil in the sump after giving heat treatment to make it moisture free and topping up with 200 liters fresh transformer oil. Refitting the top cover by providing and fitting requisite gasket, nuts and bolts of appropriate sizes. Testing the continuity of each phase and securing all connections. Shifting the repaired electric transformer back to site i.e. LIS Ismailpur in similar manner, unloading and installing at transformer hoisting channel/platform with the help of hydra crane and skilled manual labour. The job also involves providing and fitting of drop out set (complete) along with allied material after extracting out the old damaged set. Connecting of HT supply by providing and fitting of thimbles along with aluminum wire of appropriate gauge/size. Allowing the transformer to charge at no load and then connecting the LT supply and testing the transformer on full load at site. The complete job includes rebate on old parts, cost of material, labour charges, loading& unloading, to & fro carriage, testing and installation and hire charges of the hydra crane used during the execution of job.

Rebate on Old Parts

Dismantling the voltage stabilizer from the pump room after disconnecting the input and output electric supply. Draining out the transformer oil from the stabilizer then shifting the stabilizer from pump room to road side with the help of manual labor using requisite tools and tackles. Loading into mechanical transport for carriage to workshop for repair using chain pulley block/hydra crane along with required tools and tackles. Repairs to 100 KVA voltage stabilizer at workshop by way of dismantling its top cover, extraction of inner frame with coil assembly, removal of burnt out 3 No. copper leg coils, damaged rotary switch-03 no., and bus bar of appropriate rating, nuts & bolts. Rewinding of 3 No. copper leg coils, insulating and varnishing by standard quality varnish. De moisturizing the coil assemblies in the oven, cleaning of tank with the help of appropriate cleaning agent. Lowering of the coil assembly inside the sump of the stabilizer. Providing fitting of 3No. rotary switch as per sample along with new brass nuts & bolts, Bakelite sheet, copper thimbles, voltmeter-01 no., Providing and fitting of on load changeover switch 160 A after extracting the damaged old one along with thimbles of appropriate rating /size. Providing and filling of 100 liters T. Oil for topping up the voltage stabilizer after giving heat treatment to demoisturize it. Assembling the top cover by providing and fitting gasket along with nuts and bolts, Testing the continuity of each phase and after securing all the connections. After complete repairs back carriage of 100 KVA voltage stabilizer in similar manner from workshop to LIS Ismailpur. Installation, testing and commissioning of the voltage stabilizer on no load and full load conditions at site. The complete job includes rebate on old parts, cost of material, carriage, hire charges of tools and tackles and testing at LIS Ismailpur.

Rebate on Old Parts

PERFECT ELECTRICAL WORKS

M/S RAGHUNATH MECHANICAL AND ELECTRICAL ENGINEERING WORKS

N B Engineering and Electric Works

ROYAL ENGINEERING ENTERPRISES

M/S GOPAL ELECTRICAL

PERFECT ELECTRICAL WORKS