| 摘要 |
PROBLEM TO BE SOLVED: To solve the problem wherein warping of a link of performing a process of punching a through-hole first, becomes larger than warping of a link of performing a process of punching a through-hole later.SOLUTION: A plural-row taking processing method is used for successively performing plural-row processing to a hoop material 20 with respective rows, and includes a first process of returning a punched work W1 to the hoop material 20 by punching the work W1 having an external shape of a link from the hoop material 20, and a second process of punching through-holes 12 and 13 from the work W1. After performing the first process to the whole four rows, the second processes B1 and B2 are performed to two rows among the four rows. Next, after performing third processes C1 and C2 of discharging a work W2 to which the second processes B1 and B2 have been performed, the second process is performed to residual two rows. |
