GB822168A - Improvements relating to solid-insulated joints between insulated high-voltage conductors - Google Patents

Abstract

822,168. Cable joints. REYROLLE & CO. Ltd., A. Dec. 13, 1955 [Dec. 15, 1954], No. 36263/54. Class 38 (1). A bolted connection between three highvoltage conductors 10, 11, 12 each embedded in synthetic resin or other solid insulation 13, is reinforced by a metal plate 15 and enclosed in a box 20 of synthetic resin formed by enclosing the joint in a mould and pouring the resin into it, the latter then converting into the solid state by polymerization, the ends of the conductors being first coated by a resin-impervious compound. A cold-setting resin, e.g. an unsaturated polyester resin cross-linked by a modifying agent such as styrene and loaded with a filler such as powdered slate or silica is suggested. An insulating compound 16, e.g. talc and castor oil is provided immediately round the joint, sponge rubber pads 17 being embedded in the compound to permit shrinkage of the synthetic resin during moulding and to prevent cracking of the box during thermal expansion of the compound 16. The pads 17 are coated with electrically conducting paint to prevent electrical stressing of the air pockets, a thin film of silicone grease being then applied so that the compound can easily be removed from the pads when the joint is being dismantled.