| 摘要 |
In a method for heated tool butt welding of pipe consisting of a thermoplastic material by placing or pressing the surfaces to be joined of the pipes to be welded into contact with a heated tool to form an inner weld bead at each end to be joined, subsequently heating the surfaces at a reduced contact pressure to the welding temperature and fitting the surfaces together under pressure after having removed the heated tool, the improvement for minimizing the formation of a protrusion within the resultant pipes which comprises pressing an elastic insert against the inner weld bead while joining said surfaces of said pipe together. |
