| 摘要 |
PURPOSE:To reduce the generation of burr by reducing the sectional area of an article to be sheared such as thick-plate shaped continuous steel material, etc., into a constricted state before said article is sheared and applying closed-type shearing onto the constricted part thereafter. CONSTITUTION:In the previous stage to shearing, a pair of a lower blade 4 and a lower clamp 18 in lock state is pulled-up towards a pair of an upper blade 1 and an upper clamp 19 in lock state, with respect to an article to be sheared which is set on a pass line P, by means of a main cylinder 12 and a main ram 10, and the article is pressed between the main cylinder and the main ram and plastically deformed to form a constricted part corresponding to a chevron shaped-shaped section. During the execution of shearing in the posterior stage, the above-described constricted part is sheared by the upper blade 1 and lower blade 4. |
