repair to transformer of capacity 500 kva with sm no 263 / 3249 / tr / 16 under ge ( north ) patiala ( make crompton ) . , repair to the transformer including following:- ( a ) taking down unsv transformer from site and transporting to yard . ( b ) opening of top cover and lift up of core for inspection of defect through tripad and chain pulley block . ( c ) draining of transformer oil ( d ) taking down and replacement of windings of ht side one limb-4 coils with new coil of weight 50 kg / coil ( e ) fixing of new coil in limb ( f ) baking of core in furnace ( g ) coating of tank with zinc chromate paint to avoid rusting of tank ( h ) lowering the core in tank and filling of 450 ltrs of transformer oil of specific gravity 0 . 89 max and dielectric strength not less than 60 kv ( j ) fixing the top cover and tap changer connection ( k ) testing of transformer before installation at site . ( l ) transportation of transformer to site for intallation and commission . note:- 1 . test result shall be recorded after repair . 2 . old dismanteled material i . e transformer oil and coils shall be the property of department .