| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a premold insulator by which the formation work of a cable connection can be conducted, in setting a premold insulator free onto a cable sheath in advance. SOLUTION: This premold insulator possesses an insulating rubber part 8 constituted of insulating ethylene propylene rubber, an outer semiconductive layer 6 constituted of conductive ethylene propylene rubber, and an inner electrode 7. In this premold insulator 5, when the rupture elongation in tensile test of both ethylene propylene rubbers exceeds 300% and the residual elongation, after leaving it standing for four hours is in 150% elongated state, is set to 15% or smaller. Hereby, even if the diameter expansion work of 300% diameter expansion percentage, cracks do not occur in the premold insulator, and adequate fastening force can be obtained even after the diameter expansion work is conducted.</p> |
