SPECIAL REPAIR TO 33/11 KV 3.15 MVA POWER TRANSFORMER AND CONNECTED ITEMS FOR FEEDING POWER SUPPLY TO BOTH NAMKUM AND KHOJATOLI POCKET UNDER GE RANCHI

Amount

Disconnecting/ decanting of oil, all electrical and external connections of the transformer of capacity 3.15MVA, 33/11 KV Lifting from its position using all necessary arrangements without damaging, loading in vehicles, transportation to the workshop and vice versa, dismantling transformer for rewinding/repairing/ replacement of any necessary spares, Dehydration of core assembly by heating in oven, Inspection of transformer tank for leaks and incl rectification of leaks by welding/bracing etc, removing of sludge from tank, Making of all internal connections using all necessary strips/connectors, including replacement of entire gasket, checking the acidity of oil and insulation test before and after & subbmitted the report with installed, testing and commissioning after repairing carried out of transformer complete as per directed. Note:- (i) payment of defective parts to be replaced shall be measured and paid separately under respective item of sch and replacement of all other material such as top gasket , insulators gasket, shut off/ drain/ filter valve, Air release plug etc shall be part of this item and no extra payment shall be made for the same (ii) Before repairing for analysis of damage of core and winding (33KV/11KV) pre Inspection of transformer and inspection after repairing carried out as per policy in vogue at authorized transformer factory and no extra payment shall be made for the same. (iii) The transformer with off load tap changing gear shall have taps ranging from +5% to -15% in 8 equal steps of 2.5 % each on HV winding for voltage variation including match with OEM specifications and no extra payment shall be made for the same (iv) Before and after installation of tranformer all safety measures check like over currect protection/ earth fault protection functioning properly and testinng carried out as per policy in vogue and no extra payment shall be made for the same. (v) In this effect GE/ AGE E/M shall certified and shall obtained 02 years warranty from the contractor.

Rewinding of Transformer of 3.15 MVA capacity with electrolytic grade copper as per IS: 2026 delta connection on promery side (33KV) and star connection on secondary side (11KV) including match with the same side of old winding and turns with new press board insulation, necessary insulation packings/ paper insulation etccomplete all as directed. (Note – i. The coil to be replaced shall have same number of turns ,gauge, insulation value matching with manufacture's design. ii. Old HV/LV copper coil (Sch of credit items) will be handed over to the contractor after the successfully commissioning and testing.)

Supply and replace HT 33 KV bush with arching horns suitable for outdoor type 3.15 MVA transformer complete with brass stud, 3 Nos brass nuts/brass cup complete all as directed

Supply and replace HT 11 KV bush and neutral bush with arching horns suitable for outdoor type 3.15 MVA transformer complete with brass stud, brass nuts/brass cup complete all as directed

Supply and replacement OTI / WTI 150mm dial type having range 0-120 degree centigrade vapour pressure with maximum reading pointer/ max temperature indicaor and resetting device with alarm and trip contact and additional contacts for swiching on/ off the cooling fans complete all as directed.

Supply and fill up transformer oil as in topping up/refilling of transformer having dielectric strength not less than 60 KV at 4 mm gap conforming to ISI complete all as directed. ( Transformer oil shall be filled after necessary heating , moisture free with dielectric strength as specified above )

Rubbing/scratching old paint of transformer outer/inner parts of capacity 3.15 MVA, through sand/ shot blast and chemical cleaning of entire inner of transformer using heat resistant paint and for external surfaces providing two coat of synthetic enameled spray paint including writing of SM / MES numbers complete all as directed.

Supply and installed in replacement of a double float type Buchholz Relay for 3.15 MVA transformer for any gas evolved in the transformer shall collect in this relay with a test cock for checking its operation including two electrically independent potential free contracts, one for alarm on gas accumulation and other for tripping on sudden rise of pressure and match with the existing complete all as directed.

Supply, installed and testing in replacement of 3.15 MVA, 33KV/ 11KV transformer core (three phase) as per old design of cold rolled grain orinted (CRGO) sillicon steel laminations with lamination thickness not more than 0.23mm to 0.27mm with requried supporting chane frame along with nut bolts & washers.The core material shall be provided by manufacturer and inspection carried out before core cutting and after core assembled and no extra payment shall be made for the same complete all as directed.

Supply and replacement of transformer breather complete with silca-gell for capacity 3.15 MVA transformer.

S&F in replacement XLPE insulated screen, PVC badded galvanized steel strip or wire armoured electric, power cables heavy duty with aluminium conductor 33KV/11KV, earthed system cross sectional area 120 Sq mm X 3 core laid in trenches or passing through pipe or fixed to wall/poles complete all as directed.

Supply and fix cable jointing kit for 33 KV grade cable for outdoor termination heat shrink type joint complete with jointing material and accessories suitable for 3 core XLPE, armoured, Al conductor cable of size120 Sqmm complete all as directed

Earthing complete with using copper plate 60×60cm ×3.15mm thick electrode, buried directly in ground (earth pit not less than 2.25 metres deep below ground level) with top edge of the plate not less'than 1.5 metres below normal ground level, connected to galvanised iron strip 20×3mm size by means of bolts, check nuts and washers of GI and earth strip protected by provision of GI pipe light grade, 25 mm bore including provn of concrete pit in PCC (1:2:4) type B-1 using 20 mm graded crushed stoned aggregates with 40 mm thick cover of RCC (1:2:4) reinforced with XPM (weight not less than 4 Kg/Sqm) and frame of angle iron 25x25 x3mm with lugs 2 Nos and with 6mm dia MS bar handle made to shape, GI medium grade 20mm bore pipe for watering perforated at bottom 1.75 mtr long placed on top edge plate, common salt and charcoal filling, test pont made out of phosphorous bronze with fixing arrangement, funnel, wiremesh and earth work in hard/dense soil, returning filling in and removal of surplus soil to a distance not exceeding 50 mtr, all as per electrical plate No 3 of SSR 2009 Part-I and connection all as directed and testing on completion.

Earthing complete with galvanised steel earth plate electrode 60cmx60cmx6 mm thick buried directly in ground.(earth pit not less than 2.25 mtr deep below normal ground level) with top edge of plate not less than 1.5 mtr. Below ground level connecting to GI Strip 32x6 mm size by means of bolts, check nuts and washers of GI and earth strip protected by provision of GI pipe light grade, 40 mm bore including provn of concrete pit in PCC (1:2:4) type B-1 using 20 mm graded crushed stoned aggregates with 40 mm thick cover of RCC (1:2:4) reinforced with XPM (weight not less than 4 Kg/Sqm) and frame of angle iron 25x25 x3mm with lugs 2 Nos and with 6mm dia MS bar handle made to shape, GI medium grade 20mm bore pipe for watering perforated at bottom 1.75 mtr long placed on top edge plate, common salt and charcoal filling, test pont made out of phosphorous bronze with fixing arrangement, funnel, wiremesh and earth work in hard/dense soil, returning filling in and removal of surplus soil to a distance not exceeding 50 mtr, all as per electrical plate No 3 of SSR 2009 Part-I and connection all as directed and testing on completion.

Earth continuity conductor or main earthing lead fixed to wall on batten or recess or chases or buried in ground or drawn in conduit/pipe or fixed to poles or any other indicated situation for loop earthing etc. as required but 20x3mm copper strip complete all as directed.

Earth continuity conductor or main earthing lead fixed to wall on batten or recess or chases or buried in ground or drawn in conduit/pipe or fixed to poles or any other indicated situation for loop earthing etc. as required but 32x6mm galvanised iron strip complete all as directed.

Associated Engineers

M/S Akash Enterprises