| 摘要 |
1,203,949. Cable joints. PIRELLI S.p.A. 21 Sept., 1967 [30 Dec., 1966], No. 42917/67. Heading H2E. A coded joint for connecting pipe cables 1, 1<SP>1</SP> comprises a prefabricated insulating sleeve 10 within a metal casing 13 double walled to provide a hollow space 17 for cooling fluid, and sealed at either end by substantially cylindrical insulating members 14, 14<SP>1</SP> which are in turn sealed to the cable sheaths 4, 4<SP>1</SP> via conical metal members 21, 21<SP>1</SP>, so that the oil within the easing is isolated from the cooling fluid, e.g. water within the cable pipes 6, 6<SP>1</SP>. Members 14, 14<SP>1</SP> thermally isolate the latter coolant from the colder coolant, e.g. brine used to cool the joint and prevent freezing within the cable pipes, and also isolate electrically the cable sheaths and pipes from the casing, flanges 15, 15<SP>1</SP> optionally having a ribbed surface to increase the path length and prevent surface discharges. In making the connection, which as shown is a straight through joint, the bared conductors 2, 2<SP>1</SP> are secured in connector 8 e.g. by brazing and layers 9 of reconstructed insulation applied. Stress cores 11, 11<SP>1</SP> electrically connected to the cable screen 5, 5<SP>1</SP> are provided at each end of insulating sleeve 10. The sleeve may be of epoxy resin filled with quartz, alumina or other mineral fillers or polyester filled with glass fibres. In a stop-joint (Fig. 2, not shown) the insulating sleeve is in two parts for ease of assembly, and modifications of the sealing of the sleeve are described. |
