| 摘要 |
PCT No. PCT/SE87/00291 Sec. 371 Date Feb. 21, 1989 Sec. 102(e) Date Feb. 21, 1989 PCT Filed Jun. 23, 1987 PCT Pub. No. WO87/07935 PCT Pub. Date Dec. 30, 1987.A method of joining tubes (A and B) having a corrugated wall (10) of fusible plastic material and terminating at a cut through a corrugation rib, comprises the following steps. An annular body (14) expanding when energy is supplied to it, is positioned in an annular space (13) formed by the corrugation ribs at the end of one tube (A) and an inner boundary which can be formed by an inner wall (11) of fusible plastic material, integral with the corrugated wall of said one tube, or by a sleeve inserted into the adjacent ends of the tubes, also of fusible material. The tube ends are put together to close said space by the end of the other tube (13), and a radial and axial support (19) for the corrugation ribs is arranged on the outside of the tubes. Then, the annular body is expanded by heating to fuse said body to the walls of the tubes and the sleeve, respectively. |
