| 摘要 |
PCT No. PCT/CH79/00054 Sec. 371 Date Dec. 21, 1979 Sec. 102(e) Date Nov. 28, 1979 PCT Filed Apr. 19, 1979 PCT Pub. No. WO79/00961 PCT Pub. Date Nov. 15, 1979.An electric welding muff for joining thermoplastic line elements comprising a welding sleeve and an electrical resistance heating wire. The sleeve is formed of thermoplastic material. The heating wire is wound in a plurality of turns and embedded in the sleeve adjacent one of its lateral surfaces and has peripherally spaced deformation points diverging from the general course of the turns. During manufacture and welding, the heating wire remains in its predetermined position since expansion of the wire is absorbed at the deformation points. |
