Transformer oil treatment

The treatment of transformer oil is an important maintenance operation in the life of a transformer. Oil treatment reduces the amount of water, gases and impurities in the oil.

Transformer oil has a dual role: as a dielectric insulator and coolant. During transformer operation, voltage, time and heating cause this oil to degrade and lose its properties. Treating the transformer oil restores it to a good quality, allowing the transformer to continue to operate. The purpose of oil treatment is to remove solid particles in the oil.

  • Reduce the amount of water in the oil from the decomposition of paper (cellulose), thus increasing dielectric rigidity.
  • Eliminate gases dissolved in the oil as a result of hot spots and of partial discharges contained within the transformer.


  • specifying the work to be carried out
  • installing equipment and treating insulating oils
  • monitoring the result through oil analysis
  • preparing a work report with recommendations