| 摘要 |
PURPOSE:To prevent generation of hollows in the deformed padrt of a pipe and prevent generation of flaws on the outer wall by packing a metal of low melting point in a metallic pipe and press-forming under a condition that its outer periphery is covered with a cushion material. CONSTITUTION:Press-forming dies 2 that give a specified deformed part 1 consist of a lower die 3 on which a forming face 3a is formed on the surface and opposed guide plates 4 are fixed on the side walls, and an upper die 6 that has a forming face 5 of similar shape with the forming face 3a and guides downsard with the guide plates. A metal of low mesting point such as ab alloy of bismuth, tin, lead is flowed into a straight pipe P and cooled and solidified, and covered with a cushion material in a body. This pipe P is placed on the lower die 3 and press-formed by the upper die 6. Then, the pipe P is taken out and dipped in hot water etc. to melt the metal of low melting point. Thus, a formed metallic pipe is obtained. |
