| 摘要 |
<p>A circumferential notch(6) is formed in a blank, the displaced material(8) flowing into a rectangular circumferential rib(7) formation. The vol. of the rib is controlled and it is formed at a specified axial distance from the projected position of the triangular rib(3). The next phase effects a reduction in the shaft dia. beyond the rectangular rib, the reduction(2) being uniform and being advanced progressively in the direction of the rib. A mass of material is, thus, pushed towards the projected position of the triangular rib, finally being given the required conical form by a further set of transverse rollers.</p> |
