Internal Inspection of 315MVA, 400/220KV ICT-I for identification and rectification of internal fault alongwith other associated Works at 400KV Sub Station Sarnath, Varanasi

Amount

Following works are to be Carried out for the Work of Internal Inspection of 315MVA Transformer-I for identification and rectification of internal fault 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 :

Shifting, Loading, Carriage & Unloading of 1 No. Oil Storage Tank of 20KL Capacity from Storage Place at the nearest Sub Station to 400KV S/S Sarnath, varanasi site in Switchyard and Loading, Carriage, Unloading & Placing of Oil Storage Tank back from T/F site to Storage Place at the Sub Station after completion of the Work. The Work includes arrangement of suitable Capacity Crane & Vehicle.

Shifting of 3 No. 20KL Oil Storage Tank and Empty Oil Drums from Storage Place at the Sub Station to near 315MVA 400 / 220KV Transformer-I including its Loading & Unloading with the help of Suitable Capacity Crane.

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

Dismantling of all HV, IV & LV Bushings of 315MVA, 400/220KV Transformer-I including turret from main tank with associated pipe lines.

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

Providing Dry Air generator at the time of internal inspection after opening of blanking plate of 315MVA ICT-I.

Internal Inspection of 315MVA ICT-I, checking of HV/LV side winding lead by the help of crape paper to increase the insulation of bushing lead and its proper repairing of Transformer leads, tightening of joints, connections and all other components inside the main tank of 315MVA T/F.

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 of 400KV Turrets (Top & Bottom)

Gaskets of 400KV Bushings

Gaskets of 220 KV Turrets (Top & Bottom)

Gasket of 220 KV Bushing

Gasket of 33KV Turrets (Top & Bottom)

Gaskets of 33KV Bushings

Gaskets of 33KV Bushings of Top Seal

Performing the Vacuum stand test. The scope of work involves creating the vacuum inside the Transformer up to 70 Hg mm for evacuation of moisture from core & winding and maintaining the pressure at least for 72 hrs.

Complete Evacuation of main tank of the Transformer and filling of dry air 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 / 24 hrs) using certified machine. The scope of work involves Measuring dew point valves of N2 after every cycle till required value is achieved.

Centrifuging of Oil filled in Oil Tanks, Un-interrupted till the desired BDV 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.

Erection of all HV, IV & LV Bushings of 315MVA, 400/220KV Transformer-I including turret from main tank with associated pipe lines.

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.

Dissolved Gas Analysis (as per IS Norms) along with collection charges of 5 No. Oil Samples of 315MVA, 400/220KV ICT-I. 1st Oil Sample for testing will be taken before charging, 2nd Oil Sample for testing will be taken after 24 hrs. of charging, 3rd Oil Sample for testing will be taken after 7 Days of charging, 4th Oil Sample for testing will be taken after 15 Days of charging and 5th Oil Sample for testing will be taken after 30 Days of charging.

Meena Elect & Engg. Works