MANUFACTURE OF INSULATING TUBE FOR ELECTRIC CABLE

摘要

PROBLEM TO BE SOLVED: To prevent the occurrence of forming defects in which semiconducting conductive rubber enters into the thin tip parts of slope parts at both ends of a reinforcing insulator. SOLUTION: An inner semiconducting layer 2 is arranged at a prescribed position at the outer periphery of a core member 1. Outer semiconducting layer stress cone parts 4a and 4a are arranged on both sides at a prescribed interval with respect to the inner semiconducting layer 2, so that respective slope-type recessed parts 4b and 4b face the side of the inner semiconducting layer 2. A reinforcing insulator 3 is formed on the outer periphery of the core member 1, so that it covers the inner semiconducting layer 2, and the respective slope- type recessed parts 4b and 4b of the outer semiconducting layer stress cone parts 4a and 4a are filled with it in such a state. Then, the outer semiconducting layer 4 is formed by covering the outer periphery of the reinforcing insulator 3 and is made to straddle the outer semiconducting layer stress cone parts 4a and 4a.