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Specialist Materials for Industry and Science

Welcome to Midel Ester-Based Dielectric Fluids

Midel is the world’s leading brand of ester-based dielectric fluids and is chosen by utilities and transformer manufacturers worldwide because of its excellent track record and ability to minimise risk.

We offer two types of ester - our synthetic ester MIDEL 7131 and our natural ester MIDEL eN, both provide the crucial combination of fire safety and environmental protection properties that are absent in mineral oil. They can also significantly extend the life of your transformers. Synthetic and natural esters (vegetable oils) have been successfully used in new and retrofitted liquid-filled electrical equipment installations for many years. To see how mineral oil compares to esters please visit our Fluids Comparison.

As well as offering a safe alternative to mineral oil, we pride ourselves on being the experts in the production of ester-based dielectric fluids and delivery of unparalleled levels of excellent technical support. For assistance in choosing the right fluid for your project contact us today. To learn more about esters visit About Esters

Our products

MIDEL 7131

A synthetic ester, suitable for breathing and sealed transformers situated indoors or outside, including in cold climates. The more robust fluid in the range, with use in a wide variety of applications.
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A natural ester, suitable for sealed transformers indoors or outside, in temperate climates. MIDEL eN is regularly used in distribution transformers because it is a cost effective, fire safe alternative to mineral oil.
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  • Apiezon
  • Metrosil
  • Midel
  • Wolfmet

Products of M&I Materials Ltd.