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Specialist Materials for Industry and Science

Dielectric Oils

Dielectric Oils

Ester-based dielectric oils have been shown to be a high performance alternative to mineral oil for use in transformers. Mineral oils have been used for many years to help transformers perform at their maximum level, but studies have since revealed them to be flawed.

They have been shown to be highly flammable, they contain corrosive sulphur, have poor moisture tolerance and are bad for the environment, all of which makes ester-based transformer oils from Midel a much better alternative.

Midel's natural and synthetic esters perform the same task as mineral oil in a safer, more environmentally friendly fashion.

Synthetic Transformer Fluid

Synthetic ester MIDEL 7131 performs well in many applications, including high risk locations such as underground or offshore. It can be used in both sealed and breathing transformers.

Its reliability sets it apart from competing products, and its various properties reveal why MIDEL 7131 is a better option than mineral oil.

First and foremost, it has a high fire point of 300°C and a 100% fire safety record, ensuring you are protected from the extensive damage a fire can cause. It is also environmentally friendly, non-corrosive and low maintenance, becoming known as the 'fill and forget' fluid.

Natural Dielectric Oil

Manufactured using renewable materials, MIDEL eN is an ideal product for those seeking environmentally friendly transformer oils. Its excellent biodegradability reduces damage in the event of a spillage, and laboratory tests have shown it to be non-corrosive. Furthermore, like MIDEL 7131 it has a high fire point.

MIDEL eN performs best in sealed transformers, and as such is well suited to tasks involving distribution transformers located indoors or in busy areas.

More Information on Midel Transformer Oils

If you would like to find out more about Midel dielectric oils, you can contact us or browse the documents page to find the answers you need.



  • Apiezon
  • Metrosil
  • Midel
  • Wolfmet

Products of M&I Materials Ltd.