| 摘要 |
A method is disclosed for closing the opening of each of the through-holes formed in the pipe-wall of a resin pipe and extending parallel to the axis of said pipe. The method comprises pressing one end portion of the pipe in a direction parallel to the axis in a mold for closing the openings, the mold being connected to a high frequency current source. The end portion is then heated by applying a high frequency current to the mold so as to melt the hole-partition walls which partition the throughholes, and the inner surface of the through-holes, thereby closing the openings. |
