| 摘要 |
A flat sheet metal blank is cut into a ring-shaped part (10), and this is formed into a hollow profile with a cross sectional angle of more than 180 degrees . For at least part of the forming process, the ring-shaped part is moved between two rotating rollers (22,24). In one forming stage, the part is drawn to give it a mainly U-shaped profile with two legs (18,20) of different length. The rollers bend the radially outer longer leg (20) in a radially inward direction. A number of holes is punched into the part before forming. |
