To reduce thermal stresses acting on the insulated core and sealing section of a plastic power cable, so as to improve the response of the cable to dimensional variation by arranging an external case in contact with the external side face of the semiconducting rubber section of a stress cone.
On an insulated core 1 of a cable provided with an insulator of cross-linked polyethylene, etc., a stress cone 4 formed by integrally molding an insulating rubber section 41 and a semiconducting rubber section 42 is mounted closely to the outer peripheral surface of the core 1. An inclined end section 51 of an external case 5 provided over a connecting section is arranged in contact with the external inclined surface of the cone 4, and the case 5 is filled up with a pressure medium 10, such as the SF6 gas, silicone insulating oil, etc. When the connecting section is constituted in such a way, the cone 4 is apt to be pushed out in the axial direction by the pressure of the pressure medium 10, but the external side face of the semiconducting rubber section 42 on the cone 4 is press-contacted with the internal surface of the inclined section 51 of the case 5 and the case 5 is self-sealed.
BAN SHUNICHIRO
NAKANISHI TATSUO
