| 摘要 |
<p>PURPOSE: To provide excellent expansion and flexibility together with the heat resistance and the incombustibility by coiling a metallic strip to which the metallic reinforcing body in a spirally overlapping manner, forming a habit that the position of the reinforcing body is the apex, and achieving the ultrasonic welding of the tube wall at an overlapped part except the bottom part. CONSTITUTION: In an expandable metallic bellows tube 1, a metallic strip 5 where a metallic reinforcement 52 is added and the formation is easy is successively coiled around the adjacent metallic strip 5 in a spirally overlapping manner to constitute a tube wall. Habit is formed to that the position of the metallic reinforcement 52 is approximately the apex part 3, and the tube wall of the overlapped part 6 except the bottom part between the apex parts 3 is welded and joined by the ultrasonic method. The joined part 7 is located at the mountain shoulder part 31, and the knurling shape is preferable to the flat shape. The expandable metallic bellows tube 1 is expandable by the displacement of the valley part 4 with the apex part 3 at which the metallic reinforcement 52 of the metallic strip 5 is located being the supporting point. Thus, excellent expandability and flexibility can be obtained together with the heat resistance and incombustibility.</p> |
