| 摘要 |
PURPOSE:To form long halved pipes continuously by small pressing force without being restricted by length by passing a flat plate-like material between upper and lower dies provided with an end bending section, an entire bending section and a finishing section. CONSTITUTION:An end bending section 13, an entire bending section 14 and a finishing section 15 are provided in a lower die 11, and corresponding parts 16, 17, 18 are provided in an upper die 12. A press is attached to the upper die 12, and a flat plate-like material 12 is inserted between the dies 11, 12 from the end bending section 13, 16. A material 19 to be worked is bent successively from outside in the end bending sections 13, 16, and bent from large curvature to small curvature in the entire bending sections 14, 17. Then, it is finished to a specified curvature in the finishing sections 15, 18. By this way, long halved pipes can be formed continuously without being restricted from the material 19. |
