| 摘要 |
PURPOSE:To join a pipe to a plate material by press-contact without performing welding, by piercing a hole in the plate material to which the pipe is joined, inserting the pipe, and thereafter, expanding the fitted part of the pipe. CONSTITUTION:A hole 3 into which a pipe 1 can be inserted is pierced in an important part of a plate material 2, and also a triangular mountain-like serration 4 in the axial direction, whose height is lower than thickness of the pipe 1 is additionally provided on the inside circumference of the hole 3. Subsequently, one end of the pipe is fitted orthogonally into the hole 3, and it is held by a suitable jig. Subsequently, one end of the pipe is expanded by inserting forcibly a die 5 whose diameter is a little larger than the inside diameter of the pipe 1, from one end of the pipe 1. As a result, the outside circumferential part of the expanded pipe 1 is gnawed into the serration of the plate material 2, and the pipe 1 is joined exactly to the plate material. In this regard, depending on a kind of a material, said joining can be executed without providing the serration 4, and it is also available that a small number of serrations 4 are provided separately in the circumferential direction. Also, joining can be executed by making the hole polygonal instead of the serration 4. |
