| 摘要 |
The tube has a screw-shaped welded seam, contng. screw-shaped reinforcements in the overlap. The profile tube is reinforced by longitudinal stretching, drawing, and molecular orientation, and shaped to a tube by welding the overlapping surfaces. The tube has U-shaped recesses in the overlaps to accommodate the reinforcement, and the associated welded edges. Spec. the tube consists of a thermoplastic synthetic, and is completely conductive; the reinforcement is a steel or bronze wire, or hardened plastic. |
