| 摘要 |
PURPOSE:To obtain a valuable product without leaving straight parts at the side parts of a bent sheet materials by bending the material fed into a gap between opposing rolls as well as pressing the rolls against the side faces of the material. CONSTITUTION:A sheet material 13 is fed between an upper roll 14 and a lower roll 15 and a bending moment is given by pressing its both surfaces, then the material 13 is bent into a shape corresponding to a roll shape and, at the same time, the side face 16 of material 13 is pressed by forming a side-face pressing part 17 for pressing the side face 16. In this way, the material 13 is bent without leaving straight parts at its side parts, and is processed into a pipe without causing increased wall-thickness parts, and a valuable product is obtained. Further, rolls for pressing the side faces of material can be provided separately from upper and lower rolls. |
