Characteristics of Aged Silicone Rubber Insulators Used in Outdoor for 20 Years

To collect aged silicone rubber (SiR) insulators with different numbers of years in use, which is for developing a degradation diagnostic system of SiR, is difficult. Therefore, it is desired to make degraded SiR surface which has similar characteristics to the degraded surface in outdoor. To realize the fabrication, we characterized the surfaces of aged SiR specimens cut out from a 22 kV line post insulator used in the coastal area for 20 years. The results showed that to introduce fine particles into the surface is necessary for making degraded surface having the minute surface roughness. Additionally, it was found that to activate the dispersion of LMW with foreign matters is also necessary. © 2024 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC.