Development of a sealing insulator for an electrical penetration assembly

An electrical penetration assembly (EPA) is an interconnecting port on a containment vessel (CV) through which the cables are inserted into the CV in order to power and control the machinery inside, and also to monitor conditions such as neutron level, pressure, and temperature. Currently, in boiling water reactors and pressurized water reactors (PWRs) in Japan, epoxy resin, an organic material, is used for the insulation seal of an EPA. The purpose of this study is to replace the organic epoxy resin with inorganic glass to improve the reliability of the assembly by increasing the heat resistance.