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Site Overhauling of Transformer, Power & Distribution


We at Sumesh petroleum aim to provide end-to-end solutions for complete Transformer Overhauling and Maintenance.

Transformer Overhauling – The basic meaning of Overhauling is to examine or go over carefully for needed repairs. In the process of Overhauling Engineers open the whole Transformer to do the needful cleaning, repair and replacement, in short the process includes overall inspection including lifting of core and coils.

Inspection Stage
A team of our service engineers would visit you, to inspect and analyze the transformers and OLTC.
Inspection helps us to analyze customer requirements and transformers condition so we can plan for the future work which is to be done.
Overhauling Procedures

After the inspection and based upon the measured data, suitable course of Overhauling Procedure is recommended to improve the reliability & the Life of equipment. However, at least once in a 5 Years, overhauling is essential to restore the health of equipment.

» Visual inspection of complete Transformer for leakage points/for any damage parts etc
» Checking Manual /Electrical operation of OLTC
» Testing of Transformer (IR Value, Ratio Test, O .C. Test, S. C. Test, M. B. Test Continuity Check Test, Oil D V Test etc
» Draining of exciting oil from Transformer &OLTC in Barrels
» Disconnection of Control wiring from Buchholz relay, Surge relay , MOG, WTICT, Neutral CT etc after identification with tags
» Dismantling of Buchholz relay &connecting pipes
» Overhauling of Buchholz relay &surge relay &testing of both relay for smooth operation
» Cleaning /scrapping and removal of old gasket form top cover, Bushings, OLTC conservator
» Cleaning of core & winding by hot oil jet &removal of sludge/foreign particles from bottom of tank.
» Visual inspection of core &winding
» Tightening of core –bolts, pressure screws &checking of nut bolt of active part
» Providing paper covering on HV/LV leads, taping leads, Neutral leads & Tertiary leads. Providing new insulation at required places
» Providing new gaskets on top cover, bushing, OLTC flange etc
» Inspection of Neutral CT bushing /WTICT bushing, replacement & refitting of gasket Cleaning of deviator switch & OLTC   cylinder by hot oil jetting
» Checking & tightening of contacts, transient resistors, gears etc
» Greasing &seal replacement of gear box &refitting of deviator in OLTC
» Servicing of HV/LV bushings (with replacement of oil level glass)
» Opening, cleaning /scrapping old gasket, providing new gasket, replacement of plain oil level glass of OLTC conservator.
» Providing new gaskets and refitting of HV/LV bushings, OLTC, OLTC conservator, Neutral bushings &tertiary 
Onsite power & distribution, overhauling of transformer service - Image