| 摘要 |
A method for perforating a sheet ( 1 ) with the aid of a stamp ( 3 ) and a matrix ( 2 ) is described, the sheet ( 1 ) being elongated before the hole punching in accordance with the setpoint diameter in the hole boundary area through bulging of the hole area. In order to be able to stamp flat perforated sheets, it is suggested that the sheet ( 1 ) be countersunk through embossing in the hole boundary area on the side diametrically opposite the matrix ( 2 ) after the hole punching to equalize internal tensions.
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