| 摘要 |
A method of modifying an end face region of a spirally wound hollow section thermoplastic pipe (fig. 1), the method comprises: welding an attachment (fig.2d) to the end face region of the pipe, the attachment is formed from an extruded channel cross-section 2a formed into a circle 2b with the closed region of said channel being welded to the end face region of said pipe, thus forming a female coupling for receiving a jointing sleeve fig.5. The jointing sleeve is formed from an extruded rectangular box section formed into a circle matching the circumference of the pipe to which it is to be attached. The sleeve having electrically conductive resistance wire wound spirally around it. Preferably clamps (fig. 6) are used to hold the pipe joint together during the electric welding process. |
