Work

The following works are carried out for Replacement of Gaskets of 40MVA T/F (ALSTOM make Mfg. Year 1998 Sr. No. B-29464) alongwith other associated Works at 132KV Sub Station Biswan, with all Cost of Men, Misc. Consumables, Crane / Hydra, Centrifuging Machine, Normal & Special T&Ps, etc. Required for Satisfactory Completion of the Job, as per Technical Specifications & Direction of the Supervising Engineer, as per details below :

Carriage of 20/40 KL empty oil tank for the centrifuging of T/F oil where it is available within distance of 50 Km Approx. including carefully loading empty oil tank at 132KV Substation Neri & unloading at 132KV Biswan.

Removal of Jumpers of HV & LV side Bushings of the Transformer. The Scope of Work Involves Opening of Bolts & Nuts and Removal of Jumpers, Bushing Clamps etc.

Complete Draining of the T/F Oil from the 40MVA Transformer (ALSTOM make) into Oil Tanker / Oil Drums and Stacking them at Proper Place.

Complete Dismantling of the 40MVA Transformer (TAL make). The Scope of Work Involves Dismantling of HV / LV / Neutral Bushings, Turrets, Radiators, Conservator Tank, Explosion Vent Pipe, Buchholz Relay, Oil Pipe Lines, Flanges, Valves, Cooling Fans etc. along with Opening of associated Electrical Connections, Stacking of all the Dismantled Parts at Proper Place in the Switchyard including Proper Blanking of the Open Points before Replacement of Gaskets.

Complete Replacement of Gaskets of 40MVA Transformer(ALSTOM make). The Scope of Work Involves Removal of old / damaged Rim Gasket of Transformer's Top Cover and old / damaged gaskets of different Parts of the Transformer by Cleaning of Surfaces, Providing & Fabrication of Gaskets out of good Quality Rubberized Cork Sheet Gaskets of Konica / Troborze / Nu-Cork make having Temperature Bearing Capacity around 3800 C and Fixing the Gaskets with Adhesive at Rim & other Surfaces.

Cleaning of Transformer's Core and Winding by Hot Transformer Oil and Removing the Complete Sludge from Bottom by Flushing with Centrifuging Machine.

Complete Erection of 40MVA Transformer (ALSTOM make) by Erection of HV / LV / Neutral Bushings, Turrets, Radiators, Conservator Tank, Explosion Vent Pipe, Buchholz Relay, Oil Pipe Lines, Flanges, Valves, Cooling Fans etc. at its original Place and Complete Evacuation of Main Tank of the Transformer and filling of Dry Nitrogen / Dry Air of Dew Point -50°C or better in Vacuum upto Pressure of 0.25Kg/cm² and the again Evacuating the Transformer Tank after Required Time Interval (approx. 12 Hrs.) using Centrifuging Machine. The Scope of Work Involves Measuring Due Point Values of N2 after every Cycle till the Required Value is Achieved.

Centrifuging of Oil filled in Oil Tanker, Un-Interrupted till the desired BDV Value of the Oil is Achieved, Filling of Transformer Oil into Main Tank and Radiators from Oil Tanker, then Centrifuging & Circulation of the Oil in Transformer, Un-Interrupted till the Desired BDV Values of the Oil & IR Values are Achieved including Recording of all the Parameters such as Temperature, Vacuum, Insulation Resistance etc. every 2 Hours. Centrifuging Machine, its Operator, all associated T&Ps etc. shall be Arranged by the Contractor at his Own Cost.

Overhauling of Diverter Switch & OLTC with mechanism after Draining of Oil from OLTC Chamber, Flushing with Hot T/F Oil in OLTC Chamber and finally, Filling the Fresh Centrifuged Transformer Oil.