Insulation Board is widely used as insulation and supporting materials in transformers and instrument transformers. It has many virtues such as moderate specific gravity, high mechanical properties, easy vacuum drying, no bad inner-reaction with transformer oil, easy mechanical processing, etc. The dielectric constant of this material is close to transformer oil, so it makes a reasonable insulation match. And it can be used in the transformer oil of 105℃ for a long time.
People usually use this material to make upper/lower pressure pieces, cable supporting beams, limbs, spacer blocks in oil-immersed transformers, and clamps in instrument transformers. It replaced steel plates, insulating paper sheets, epoxy paper sheets, epoxide woven glass fabric lamination in these fields, and cut down the material expenses and weight of transformers.