| 摘要 |
<p>PCT No. PCT/GB80/00184 Sec. 371 Date Jun. 17, 1981 Sec. 102(e) Date Jun. 17, 1981 PCT Filed Oct. 28, 1980 PCT Pub. No. WO81/01259 PCT Pub. Date May 14, 1981.In manufacture of a can body by drawing a cup from a blank and subsequently redrawing the cup, one or more redrawing steps are performed by pulling the sidewall of the cup (2) by means of a punch (12) through an S-shaped path (30,24,31), whereby the wall is bent first in one direction and then in the other, to reduce its diameter, which is then reduced further in a convergent portion (20) of the die (10). The bending induces back tensions which stretch the metal and reduce its wall thickness.</p> |
