Inventors:
Ralph E. Wahl - Trumbull CT
Assignee:
General Electric Company - New York NY
International Classification:
H01B 902
Abstract:
A method of manufacturing high voltage carrying electric power cable having a conductor insulated with a multilayered covering, and the cable product thereof. The cable construction includes a primary or dielectric insulating body of thermoset ethylene-propylene rubber and a thermoset jacket about the conductor, which is substantially free of corona-prone or ionization-prone voids and separations intermediate the layers. The method comprises forming and curing the ethylene-propylene rubber compound constituting the body of the primary or dielectric insulation around the conductor and then heat treating the thermoset-cured ethylene-propylene rubber insulation prior to applying subsequent components of the multilayered covering about the condutor, including an overlying semiconductive shielding layer and a protective enclosing jacket of heat-cured thermoset polymer. The semiconductive shielding layer overlying the body or primary of dielectric insulation around the conductor, comprises a combination of a highly vapor-permeable coating of semiconductive material adhered to the surface of the underlying body of insulation and a contiguous layer of semiconductive material superimposed over the coating adhered to the insulation.