摘要 |
Hollow heat-shrinkable conductive polymer devices, particularly coupling members (2) for joining polymeric pipes (3, 4), have end sections (12, 13) of increased wall thickness so that, when current is passed through the device, the end sections are heated to a lower temperature. This avoids overheating (and consequent weakening) of that part of the pipe which is enclosed by the end section of the device. |