128/ETC-II(P)/ 2021-2022

Amount

Following works to be carried out for replacement of gaskets including other associated work for 132/33 KV 20 MVA T/F-I (NGEF make) at 132 KV S/S YPC under ETD-III Prayagraj with all cost of man, material T&P as per technical specification for proper completion of the work with due safety and precautions as per direction of supervising engineer:-

Opening of jumpers of HV/LV side bushing and removal of earthing strip from neutral bushing.

Dismantling of 20 MVA Transformer-I accessories including radiator, bushing, buchholz relay oil pipe line from conservator tank to main tank, oil pipe lie to OLTC and surge relay conservator tank.

Complete drain out of old transformer oil from the existing 20 MVA Transformer-I into empty oil drums/oil tanker and storage of oil drums at stores/designated place to storage.

Loading of 20 KL oil storage tank from 132 KV S/S Shankergarh Prayagraj then safe carriage oil tank from 132 KV S/S Shankergarh to 132 KV S/S YPC and unloading the same to the places instructed by supervising engineer. (distance approx 15 KM). vehicle/trailer and man power provided by contractor at his own cost.

Replacement of all gaskets including the top cover gaskets of transformer by providing and fixing of new gaskets as per existing size made of rubberized cork sheet Kotika/Turboze/ NU Cork brand grade 07 after due fabrication.

Cleaning of core and winding by transformer oil and removal of sludge from bottom of main tank.

Applying vacuum to above transformer up to 760 mm of HG for 24 Hrs. with adequate capacity vacuum pumps after necessary blanking/ erection as per requirement.

Filling of dry nitrogen gas having DEW point (-60°c to (-) 65°c under vacuum from top value of transformer up to pressure of 3 PSI and maintaining the same in the tank for 12 Hrs. including cost of nitrogen gas and nitrogen gas filling device.

Creating vacuum inside the main tank for period for 12 hrs. And filling of centrifuged new transformer oil in main tank of required BDV after preparation in 20 KL oil tanker.

Complete erection of 20 MVA transformer-I including radiator conservator tank, bushing with its turrets connecting oil pipe line, erection of cooling fans making control cables connection, Buchhloz relay etc. topping up of transformer oil and final oil filling in the main tank, radiator, conservator tank and all other accessories.

Centrifuging of following transformer oil in transformer tank or oil tanker by connecting centrifuging pipes, circulating the transformer oil through centrifuging machine and taking BDV values of the oil periodically till the required value is achieved as per direction of supervising engineer and also measurement of PPM. All labor, T&P Centrifuging machine shall be provided by contractor at his own cost.

Overhauling of diverter switch after removing of oil and dirty transformer oil from its chamber, filling the fresh centrifuged transformer oil after necessary centrifuging for proper BDV value as per norms of the transformer.

Conducting BDV, PPM, DGA, TAN DELTA tests of T/F oil of 20 MVA T/F prior to chrging and after passing of 15 days from date of charging. Job includes sample collection of T/F oil in suitable container and its transportation to NABL certified LAB and submitting its test reports. (All test charges on contractors account).

Meena Elect & Engg. Works

M/s S.S. Refregeration