TRANSFORMER OIL

Insulating oil in an electrical power transformer is commonly known as transformer oil. It is normally obtained by fractional distillation and subsequent treatment of crude petroleum. That is why this oil is also known as mineral insulating oil. Transformer oil serves mainly two purposes one it is liquid insulation in electrical power transformer and two it dissipates heat of the transformer e.i. acts as coolant. In addition to these, this oil serves other two purposes, it helps to preserve the core and winding as these are fully immersed inside oil and another important purpose of this oil is, it prevents direct contact of atmospheric oxygen with cellulose made paper insulation of windings, which is susceptible to oxidation.

Types of Transformer Oil

Generally there are two types of transformer Oil used in transformer
Paraffin based transformer oil
Naphtha based transformer oil

Some specific parameters of insulating oil should be considered to determined the serviceability of that oil.

The parameters of transformer oil are categorized as,
Electrical parameters :– Dielectric strength, specific resistance, dielectric dissipation factor.
Chemical parameter :- Water content, acidity, sludge content.
Physical parameters :- Inter facial tension, viscosity, flash point, pour point.