| 摘要 |
A method for manufacturing a screw is disclosed where a blank is rolled between two rolling dies. In each rolling die a rolling profile has been formed that comprises a host of elongated depressions. The rolling die has a first and a second end which are spaced apart from each other in the direction of rolling. During rolling, the blank is moved relative to the die from the first end in the direction of the second end. The mean pitch of the centre lines of the depressions, which pitch is defined as the quotient of the changes in the positions of the centre line in the direction across or parallel to the direction of rolling, in a region of the first end of the rolling die differs from the mean pitch in a region of the second end of the rolling die. |
