ELECTRICAL WORK

Amount

Replacement of gasket of 315 MVA Transformer/ICT-I EMCO make along with associated works at 400 kV S/S Greater Noida with all cost of men, materials, misc consumables, crane/hydra normal & special T&Ps, rail, etc. Required for satisfactory completion of work as per technical specification & direction of the J.E.(M)/ A.E.(M) as per details below- Dismantling and safe stacking of emulsifier system of the Transformer. The scope of the work involves opening of nuts, bolts pipe, nozzles etc. and stacking of all the dismantled items at proper place along with other associated works.

Shifting & carriage of 01 No. Oil storage tank & empty T/F oil drums. The scope of the work involves shifting & Loading of oil tank & empty T/f Oil at proper place along with other associated works.

Removal of jumpers of HV/IV side of the Transformer, the scope of work involves opening of bolts & nuts and removal of jumpers, bushing clamps etc.

Draining of T/F oil from Transformer into empty oil tank/ oil drums and stacking them at proper place.

Arrangement of 01 no 20-35 Ton capacity mobile crane along with crane operator of work at site with all cost of material, consumable such as Diesel lubricating oil etc. till the completion of gasket replacement work.

Complete dismantling of the Transformer. The scope of work involves removal of conservator tank, radiators, bushings, Turrets, complete oil pipe line, cooling fans, OLTC drive mechanism, oil pumps & associated pipe lines, flange valves etc. stacking of all the dismantled parts all proper place along with other associated works.

Lifting of main tank body of the Transformer, the scope of works involves opening of nuts, bolts of Rim gasket of main tank body, jacking & lifting of top cover, fixing of limiters and pipe stoppers between top cover and winding during replacement of gasket, then refitting the top cover after completion of the replacement of gasket as per details at Sl. No. 8 along with other associated works.

Replacement of Rim gasket. The scope of works involves removals of damaged gasket, cleaning of Rim surface, fabrication of Rim gasket out of 20mm thick rubber gasket of Konica /Troboze /Nu- cork make having temperature bearing capacity around 380 o C and fixing the gasket adhesive at Rim surface.

Replacement of old gasket from different parts of the Transformer as per details below. The scope of works involves removals of gaskets, cleaning of surface, fabrication of gasket of appropriate size out of gasket of thickness 12/10/8/6mm of Konica/Nu-cork make and fixing of gasket at proper place with adhesive along with other associated works. Gasket of 400kV Turrets(Top & Bottom)

Gasket of 400kV Bushing

Gasket of 220kV Turrets(Top & Bottom)

Gasket of 220kV bushing

Gasket of 33 kV bushings

Gasket of 33 kV bushing of top seal

Gasket of Neutral Bushings

Gasket of Neutral Bushings Turrets(Top & bottom)

Gasket of main tank inspection cover

Gasket of HV/IV/LV/Neutral Bushing cover

Gasket of CT connection plate cover

Gasket of PRV flange of main tank

Gasket of main oil pipe between main tank & radiator

Buchholz relay gasket

Teflon washer for air release plug

Gasket of oil pipe line between main tank & conservator

Gasket of oil surge relay & oil pipe line

Gasket of OLTC Top plate

Gasket of drain valve/sampling valve 1” dia pipe

Gasket of drain valve 2” dia pipe

Gasket of drain valve 3 & 4” dia pipe

Gasket of drain valve 6” dia pipe

Gasket of 200NB oil pump

Gasket of flow meter(Indicator 100 mm thickness)

Gasket of pipe line flange 100mm

Radiator gasket (150X 150mm in square shape)

Radiator valve gasket(150X150mm size in square shape)

Header joint (400mm dia size)

Air release nylon washer on radiator cap

Gasket of M.O.G. Indicator

Gasket of conservator tank

Gasket of NRV

Replacement of defective nuts, bolts of different size as required.

Draining out the transformer oil from OLTC chamber, overhauling of diverter switch, then flushing with hot T/F oil in the chamber.

Cleaning of flushing of the Transformer winding in main tank with hot T/f oil through certified machine

Complete erection of the transformer . The scope of work involves refitting of all the dismantled parts of the transformer such as radiator, conservator tank, bushing, turrets, connection oil pipe lines, cooling fans, OLTC drive mechanism, oil pumps & associated pipe line etc. The work also involves attending of the oil leakage, if any after refitting of transformer oil under vacuum in the tank as per details at Sl. No. 23

Complete evacuation of main tank of the transformer and filling dry Nitrogen/Dry air of the dew point 50 o C of the better in vacuum up to 0.25g/Sq. cm and the again evacuation the transformer tank after required time interval(approx. 12/24 Hrs.) using certified machine. The scope of work involves measuring dew point values of N2 after every cycle till required values is achieved.

Performing the vacuum stand test. The scope of work involves to create the vacuum inside the transformer up to 70hg mm for evacuation of moisture from core & winding and maintain the pressure at least 72 Hrs.

Centrifuging of oil filled in oil tanks, un-interrupted till the desired BDV value of the oil is achieved, filling of transformer oil into the main tank and radiators from oil tank as per details at Sl. No.16, then centrifuging & circulation of the oil transformer, un-interrupted till the desired BDV value of the oil is achieved including recording of the all parameters such as temperature, vacuum, insulation resistance etc. hourly. Centrifuging machine, its operator, all associated T&Ps etc. shall be arranged by contractor at his own cost.

Filling of the transformer oil into main tank and radiators from oil tank under vacuum after performing the vacuum stand test successfully as per details at Sl. No. 22

Jumpering of HV/IV side bushing of the transformer. The scope of work involves tightening of bushing clamps with appropriate sizes bolts & nuts including replacement of clamps, jumpers etc. as required.

Refitting of emulsifier system on the transformer. The scope of the work involves shifting of dismantled parts of emulsifier system such as pipe lines, valves, accessories etc. to the site and connecting them properly with successful operation of the emulsifier system.

Gupta Elect and Engg Works

Perfect Power Transformer Associates