International Standard for Insulating Rubber Sheet Testing

The insulation rubber sheet has a wide range of uses. In order to ensure its safe and effective use, the International Testing Center has developed relevant inspection standards for the insulation rubber sheet, as follows.

First, check the appearance of the rubber sheet.

1. The depth and height of the scar cannot exceed the thickness tolerance of the rubber sheet.

2. The depth and length of impurities cannot exceed 1/6 of the rubber sheet's thickness.

3. Within 5 square meters, there should be no more than 5 bubbles with an area less than 1cm², and the distance between any two bubbles should be greater than 40mm.

4. The width of the uneven edges does not exceed 10mm, and the length does not exceed 1/10 of the total length of the rubber sheet.

5. There must be no cracks on the surface.

Secondly, you must ensure that the insulating rubber sheet's Shore hardness is between 55 and 70, water absorption is ≤1.5%, permanent deformation is ≤25%, and tensile strength reduction rate is ≤30%.

In addition, the specifications of tensile strength and elongation at break of insulating rubber sheets are as follows:

1. Tensile strength (Mpa) ≥5.0.

2. Elongation at break ≥250%.

Finally, after testing for electrical insulation performance, insulating rubber sheets need to meet the following two points:

1. Withstand voltage test: 25KV (effective value), keep for 1min, there should be no breakdown.

2. Breakdown voltage test ≥35KV (effective value).