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Specialist Materials for Industry and Science

Transformer Insulation

Transformer Insulation

Midel's natural and synthetic esters are both much more suited to the task of transformer insulation than previously widely used mineral oils. Both offer a number of key features now recognised as vital for carrying out this task safely and in an environmentally friendly way.

Transformer insulating oil from Midel

The main advantage of using Midel transformer oils over mineral oil is their far greater fire safety. Mineral oils have long since been recognised as a fire hazard, but Midel's natural ester MIDEL eN and synthetic ester MIDEL 7131 both possess a 100% fire safety rating.

Midel esters are also fully biodegradable, whereas mineral oils are not, so using our transformer insulation fluid is much better for the environment. MIDEL eN and MIDEL 7131 are also suitable in certain specific situations, such as those involving power and distribution transformers, and work better in high temperatures when compared with mineral oils.

Comparing MIDEL eN and MIDEL 7131

While both MIDEL eN and MIDEL 7131 transformer oils are both superior to mineral oil, there are some tasks for which the properties of our synthetic ester give it the edge.

As natural esters tend to have relatively poor oxidation stability, they are unsuitable for breathing transformers. MIDEL 7131 can still perform at its optimum level in either breathing or sealed transformers.

Furthermore, MIDEL 7131 is more suited to tasks involving wind turbine transformers and rolling stock transformers.

In situations where it is suitable to use, MIDEL eN has the advantage of coming directly from a natural, renewable source in the form of rapeseed oil, making it a greener option for the environmentally conscious.

Find out more about transformer insulation

If you'd like more information about Midel esters to help you decide which would be best for your project, you can Contact us and our multilingual team of transformer fluid experts will be happy to advise you. Alternatively, you can consult our Documents for the information you need.



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Products of M&I Materials Ltd.