| 摘要 |
<p>The method of using the frictional heat and pressure produced by a rapidly rotating non-cutting piercing tool to weld two or more parts, such as a piece of tubing on one hand and a plate, a tube or another body having locally a relatively thin wall on the other hand, together, to which end said piercing tool is forced through the two or more parts after the latter have been placed in the exact relative positions.</p> |
