CENTRIFUGING OF COMPLETE TRANSFORMER OIL OF 400/220KV 315MVA ICT-III AND 400KV 125MVAR BUS REACTOR AND REPLACEMENT OF DAMAGED GASKETS OF 400/220KV 315MVA ICT-III ALONGWITH OTHER ASSOCIATED WORKS

Amount

Centrifuging & Circulation of Transformer Oil (Minimum 72 Hours) of 400KV 125MVAR Bus Reactor, un-interrupted till the desired BDV & PPM (Less than 5 PPM) Values of the Oil & IR Values of Bushings are achieved including Hourly Recording all the Parameters such as Temperature, Vacuum, Insulation Resistance etc. Centrifuging Machine, its Operator and all associated T&Ps shall be arranged by the Contractor at his own cost.

Following works are to be Carried out for the Work of Partial Replacement of Gasket of 315MVA Transformer-III (M/s. EMCO make, Sl. No. – HT1897/13332, Year of Manufacturing – 2011) alongwith associated works at 400 Sub Station Sarnath, Varanasi with all cost of Men , Materials, Misc Consumables, Crane / Hydra, Normal & Special T&Ps, Rails etc. requied for Satisfactory Completion of work, as per Techinical Specification & direction of the J.E(M) / A.E(M) as per details below :

Partially dismantling & safe stacking of Mulsifire air Pipe line, water pipe line and proper stacking.

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

Loading, Shifting and Unloading of 4 No. Oil Tank of Capacity 20KL with the help of Hydra / Crane from Storage place to near Working site and put back the same from Working site to safe Storage place after Completion of Job as per instruction of Supervising Engineer.

Draining of T/F oil from Transformer into empty Oil Tanks / Oil Drums and Stacking them at proper place.

Complete Dismantling of the Accessories of the 315MVA 400 / 220KV Transformer-I including Removal of Conservator Tank, Radiators, Pipe Lines, Bushings, Turrets, OLTC drive Mechanism, Oil pumps & associated Pipe line, Flange Valves etc., then Fixing of Blanking Plates on the Radiators, Pipe Lines, Conservator Tank Turret etc. (Blanking Plate including Bolts & Nuts, as Required and not Available shall be Provided / Arranged by the Contractor) and Stacking of all the dismantled parts all proper places along with other associated works.

Replacement of Old Gasket from different parts of the Transformers as per details below. The scope of works involves removal of Gaskets, Cleaning of surface, Fabrication of Gaskets of appropriate size of thickness 12 / 10 / 8 / 6 mm of Konica / Nu-Cork make and fixing of Gaskets at proper place with adhesive along with other associated works. Gaskets are of Type C, Very Good Oil Resistant and as per IS 4253 and Contractor must have to submit Test Report of Gaskets before replacement.

Gaskets of 400KV Turrets (Top & Bottom)

Gaskets of 400KV Bushings

Gaskets of 220 KV Turrets (Top & Bottom)

Gasket of 220 KV Bushing

Gaskets of 33KV Bushings

Gaskets of 33KV Bushings of Top Seal

Gaskets of Neutral Bushings Turrets (Top Bottom)

Gaskets of Main tank Inspection Cover

Gasket s of/LV/IV/ N Bushing Covers

Gaskets of CT Connection Plate Cover

Gaskets of PRV Flange of Main Tank

Gaskets of Main Oil Pipe between Main Tank & Radiator

Buchholz relay gasket

Teflon Washer for air releasing plug

Gaskets of Oil pipe line between main tank & conservator

Gaskets of Oil Surge Relay & Oil pipe line

Gaskets of OLTC Top Plate

Gaskets of drain Valve / Sampling Valve 1'' Dia. Pipe

Gaskets of drain Valve 2'' Dia. Pipe

Gaskets of drain Valve 3 & 4'' Dia. Pipe line

Gaskets of drain Valve 6'' Dia. Pipe line

Gaskets of 150NB Oil pump

Gaskets of flow Meter (Indicator 10mm thickness)

Gaskets of Pipe line flange 100mm

Radiator gaskets (180 mm x180 mm size in square shape)

Radiator Valves gaskets (180 mm x180 mm size in square shape)

Header joint (440 mm x 440 mm size in square shape

Air Release Nylon washer on Radiator cap

Gaskets of M.O.G Indicator

Gaskets of convertor tank

replacement of defective Nuts & Bolts of different sizes as required

Draining out the Transformer oil from OLTC Chamber, Overhauling of Diverter switch, and then flushing with hot T/F Oil in the chamber.

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, Connecting oil pipe lines, Cooling, fans, OLTC drive Mechanism, oil pumps & associated pipe lines etc. The work also involves attending the oil leakage, if any after Refilling of Transformer oil under Vacuum In the tank.

Performing the Vacuum stand test. The scope of work involves creating the vacuum inside the Transformer up to -760 mm of Hg for evacuation of moisture from core & winding and maintaining the pressure at least for 72 hours.

Complete Evacuation of Main Tank of the Transformer and filling of N2 of Dew Point -50°C (or better) in Vacuum upto Pressure of 0.25 Kg/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 Tanks, Un-interrupted till the desired BDV & PPM (Less than 5 PPM) Value of the oil is achieved, Filling of Transformer oil into the main tank and Radiators from oil tank, then centrifuging & Circulation of the oil Transformer, un-interrupted till the desired BDV Value of the oil is achieved including recording of the all the parameters such as Temperature, Vacuum, Insulation Resistance etc. hourly. Centrifuging Machine, its Operator, all associated T&Ps etc. shall be arranged by the contractor at his on cost.

Filling of the Transformer oil into main tank and radiators from oil tanks under vacuum after performing the Vacuum stand test successfully.

Jumpering of HV / IV / LV side Bushing of the Transformer. The scope of work Involving tightening of Bushing Clamps with appropriate sizes Bolts, & Nuts including replacement of Clamps, Jumpers etc. as required.

Refitting of Mulsifire System on the Transformer. The scope of work involves shifting of dismantled parts of Mulsifire system such as pipe lines, Valves, Accessories etc. to the site and connecting them properly with successful operation of the Mulsifire System.

Meena Elect and Engg Works

Gupta Elect and Engg Works