| 摘要 |
A fusion welding socket (18) for coupling together plastic pipes, is adapted to receive the pipe parts to be coupled together with a tight fit. The diameter of the ends (19) of the socket is greater than the diameter of the socket along an intermediate part (20) and the diameter at the ends is adapted to receive with a tight fit an outer pipe (1) and the diameter of the intermediate part is adapted to receive with a tight fit an inner pipe (2) of a double-pipe conduit which includes two coaxial pipes and a leakage detection space (3) therebetween. The socket includes coils (24-27) having resistance wires or filaments which enable the socket material to be fused locally together with the material in both the outer pipes and the inner pipes of two double-pipe conduits that are to be coupled together with the aid of the socket. The socket also includes at least one passageway (21) which interconnects the spaces in the socket on both sides of the intermediate socket part. |
