GB873751A - Improvements in or relating to high voltage bushing assemblies - Google Patents

Abstract

873,751. Insulators. GENERAL ELECTRIC CO. Ltd. Aug. 13, 1959 [Aug. 14, 1958], No. 26174/58. Class 36. An insulating bushing has a plurality of insulated leads passing therethrough, each connected at one end to a contact member, the contact members being partially encased in and insulated from each other by insulating material cast around them and secured to the end of the bushing. The leads may comprise an insulated steel rod 5 passing through the porcelain bushing 1 and surrounded by an insulated copper tube 7, the ends of both leads projecting past the bushing 1 and being externally threaded. At one end each lead is screwed and soldered into the foot 13 or 14 of a terminal 9 or 10 and the terminals are partially embedded in an epoxy resin body 18 cast around them. Sealing rings 17 prevent ingress of oil, and a sealing grommet 19 performs the same function where the insulating body 18 abuts the bushing 1. At the other end, an end-plate 20 is clamped against the bushing by a spring plate 22 secured by nuts 21 on the end of tube 7, followed by a spacer 23 and end-plate 28 secured by nuts 24 on the rod 5; the rod 5 and tube 7 thus transmitting clamping pressure to the insulating body 18. The bushing is mounted through a partition by means of a flanged member 2 provided with sealing rings 29. An alternative arrangement for five leads comprises four insulated copper rods surrounded by a brass tube disposed inside a condenser bushing within a porcelain shroud. Both arrangements are especially suited for leading through from the diverter switch compartment to the selector compartment of an on-load transformer tap changer.