Maintenance work of 315 MVA BHEL Make Generator Transformer-6 (SL. No. 6006559) and OLTC for UAT-6A (Sl. No- 2021854) under EMOPH dept.

Amount

For 189/215/315 MVA, 235/16.5 KV BHEL Make GT# 6 [Detail Specs: HV(MVA: 189(60%)/252(80%)/315(100%), LV(MVA): 189 (60%) /252 (80%) /315 (100%), No load Voltage HV(KV):235, No load Voltage LV(KV):16.5, Line Current (HV):774.81 A, Line Current (LV):11035.21A, Oil Qty. (Ltr)- 63320, Symbol: Ynd1],Serial No: 6006559

Isolation of GT #6 from both LV & HV terminal with necessary dismantling and Removing of Dropper Moose Conductor & Flexible Connector

Necessary Jobs to facilitate the Testing work of transformer along with bushing before O/H & After O/H by testing department

Disconnection of oil lines to conservator tank and radiator side & equalizer line & Blanking work prior oil draining at reasonable level

Job for Lifting, Checking, Cleaning & Servicing and change of O-ring & Gaskets of three Tap Changer Diverter Chamber after draining of oil inside chamber by proper method and Fixing after job

Servicing Job of Off circuit Tap changer drive mechanism for enabling smooth operation in all tap position and job assistance to OCTC testing.

Replacement of Gasket for all HV bushing turret after oil lowering as required Arrangement of necessary scaffolding work with dry air / N2 gas

Dismantling of existing R phase HV Bushing and Erection work of new HV bushing on base turret after testing before use by proper procedure.

Change of Other gaskets such as HV Neutral bushing gaskets, Man-hole gaskets, WTI & OTI Gaskets, Buchholz Relay gaskets, other flange gaskets (LV side inspection, equalizing pipe flanges, radiator flanges etc.) If required.

Oil Filtration after completion of jobs still achieving desired parameter of oil due to exposure to air during maintenance works prior Oil Filling

Transformer Surface cleaning, checking, oil settling, venting Jobs after completion of oil filtration & filling work

Connection of HV & LV Terminal after satisfactory transformer testing

Deputation of Skilled Manpower during Charging of GT#6 for 12 hours or more as per situation during unit synchronization.

MVA(HV) -20/16, MVA(LV) -20/16, Voltage (HV)-16.5KV, Voltage (LV)-6.9KV Current (HV)-699.81/559.85 Amp, Current (LV)-1673.479/1338.783Amp Connection- Dyn11, Cooling- ONAF/ ONAN, Oil Qty. (Ltr)- 16900

Isolation of UAT#6A from both LV & HV terminal and Necessary Jobs to facilitate the Testing of transformer before & After trf maint. job

Disconnection of oil lines to conservator tank and radiator side & equalizer line & Blanking work prior oil draining at reasonable level.

Job assistance to OEM for Oil Draining from On load tap changer tank for checking, servicing & rectification of OLTC for oil leakage from main tank of trf.

Oil Draining of UAT#6A man tank by method & Storage in tank/drums for internal inspection & rectification of OLTC for oil leakage if required after oil empty.

Blanking of transformer main tank with suitable MS blanking plate along with necessary gasket with NITROGEN gas or Dry Air sealed fully if required

Job assistance to OEM for Complete inspection of Tap Changer Part & Replacement of gaskets of suitable thickness at all flanges, joints, Inspection Top / Side cover with RC70C (Best) quality gaskets, ‘O’ rings, Teflon/nylon washers, etc.

Replacement of existing Air Cell inside conservator tank by new one after lowering the main tank oil up to required level

Change of O-ring & gaskets for HV/LV/Neutral bushing, Man-hole, WTI & OTI Gaskets, Buchholz Relay gaskets, OSR and other flange gaskets of OLTC tank & main tank at top area If required.

Oil Filtration after completion of jobs still achieving desired parameter of oil and oil top up to the required level

Connection of HV & LV Terminal after satisfactory transformer testing

TECHNO ENGINEERING