REPAIR AND MAINT OF 33 KV TRANSFORMER, VCBS, ACSR CONDUCTOR, LIGHTENING ARRESTER, BATTERY BANK ETC AT COD AND GWALIOR ROAD POWER HOUSE UNDER GE (EAST) AGRA

Dehydration and filtration of existing transformer oil in 33 KV system step-down transformers of 33/11 KV rating by means of a centrifuging / oil filtration machine at site at different locations, without disturbing the existing power supply system, including continuous operation of the filtration plant round the clock until the transformer oil attains a minimum dielectric strength of 60 KV at 2.5 mm electrode gap, carrying out insulation resistance (IR) tests on both HT and LT windings of the transformer before and after filtration, topping up the transformer with new transformer oil wherever required, reassembling all disconnected parts, checking all fittings and connections, and carrying out testing, commissioning and making the transformer fully operational, complete all as specified and as directed. Note:- New transformer oil required for topping up shall be measured and paid for separately under the relevant items of this Schedule.

Supply and filling of transformer oil conforming to IS 335:1993 (with latest amendments), for topping up or replacement in transformers up to the required operating level, including handling, filling, checking oil level, ensuring proper sealing of all fittings, and carrying out dielectric strength test of the oil, complete all as specified and as directed. Note:- The dielectric strength of the transformer oil after filling shall not be less than 60 KV at 2.5 mm electrode gap.

Disconnecting all electrical connections from the existing unserviceable transformer of capacity 2.0 MVA to 3.15 MVA, 33/11 KV, copper wound, and dismantling all necessary components for safe loading, transportation, unloading and shifting from 33 KV Main Receiving Station (MRS) to the approved workshop and back, including installation, alignment, reconnection, testing, commissioning, painting of all exposed surfaces with first quality synthetic enamel paint of approved tint, including preparation of surfaces of transformer and its mounting structure, writing of SM/MES No. as directed, and making the transformer fully operational after repairs, complete all as specified and as directed. The item includes labour only for opening the transformer top cover and carrying out repairs through a specialist / reputed transformer manufacturer or authorised repair firm, comprising the followings :- (a) Removal of transformer oil into separate barrels. (b) Taking out the core assembly along with HV and LV windings of the transformer. (c) Cleaning the inside of the transformer tank as per manufacturer’s guidelines and applying one coat of zinc-rich paint internally. (d) Vapour phase drying / ovening of the core and winding assembly at the factory workshop for 72 hours. (e) Centrifuging and filtration of the complete transformer oil before refilling. (f) Reassembling the windings and core assembly. (g) Refixing the transformer top cover with new gasket, nuts, bolts and other necessary hardware. (h) Testing and repairing radiators against leakage including soldering / brazing wherever required. Description of Item Contd.....

Item No.3 (Contd...) (j) Checking and testing the Buchholz relay and ensuring proper connection with the breaker tripping circuit. (k) Supplying and fixing necessary insulating and packing materials. Note :- (i) Replacement of bushings, spindle, oil level indicator, winding temperature indicator, oil temperature indicator, drain valve, silica gel breather and similar major components shall be measured and paid for separately under relevant items of this Schedule. (ii) Transformer oil, HV windings and LV windings shall be measured and paid for separately under the relevant items of this Schedule. (iii) Routine tests, high voltage tests, Buchholz relay tripping tests and all other mandatory tests as per relevant Indian Standards shall be carried out at the factory workshop before dispatch, and the records of such tests shall be maintained and submitted duly signed by the Contractor and the Engineer-in-Charge (iv) The quoted rate shall be deemed to include all minor spare parts, consumables, gaskets, hardware required to make the transformer electrically and mechanically functional, excluding the items specifically provided separately in this Schedule (v) The repair work shall be covered by a guarantee for a period of 12 months from the date of completion of contract. (vi) The font, style & place of writing SM /MES number with synthetic enamel paint of approved tint on transformer shall be as directed by the Enginer-in-Charge and cost thereof shall deemed to be included in quoted rates.

S&F in replacement silica gel for 33/11 KV transformer breather assembly, complete all as specified and directed

S&F in replacement brass stud on the HT side of 33/11 KV transformers of capacity 2.0 MVA to 3.15 MVA, matching the existing size, shape, rating and specification, complete all as specified and directed

S&F in replacement brass stud on the LT side of 33/11 KV transformers of capacity 2.0 MVA to 3.15 MVA, matching the existing size, shape, rating and specification, complete all as specified and directed

S&F in replacement radiator valve for 33/11 KV transformer of capacity 2.0 MVA / 3.15 MVA, matching the existing size, type, pressure rating and specification, complete all as specified and directed

S&F in replacement 33 KV lightning arrester having discharge capacity of 10 kA peak, transmission Class-2, including cleaning contact surfaces and terminals, replacing defective minor accessories, refixing in position, reconnecting HT and earth connections, testing and making the lightning arrester fully serviceable, complete all as specified and directed

S&F in replacement gasket set made of rubberised cork / neoprene material for 33/11 KV power transformer of capacity 2.0 MVA / 3.15 MVA, matching the existing size and specification, complete all as specified and as directed.