| 摘要 |
PURPOSE: To achieve medium-resistant connection of pipe pieces for manufacturing a corrugated pipe by welding female pipe parts and male pipe parts alternately continuing in the central axial line direction in the longer direction with a thermoplastic corrugated pipe. CONSTITUTION: A male pipe piece 5a welded with a welding sleeve 16 has a little upset part at a position shifting to each adjoining side part 7 on the outside of the welding sleeve 16. After connections of two pipe pieces 12 and 13 with the welding sleeve 16 are achieved, electric current is cut off and plasticized plastic articles are solidified at these positions to achieve medium- resistant welding of two pipe pieces 12 and 13. As the inner ring 17 of the welding sleeve 16 is not heated, the inner ring is not deformed in the arrow mark directions 26 and 27 even under welding pressure. Especially, the inner ring 17 is not projected to the inside in the radial direction across a female pipe part. |
