| 摘要 |
One or more closed perimeter openings are formed in the compression area of a flange of a member that is to be bent transversely to the flange. The member is bent along a transverse bend line, and the flanges are bent inwardly on themselves. The bending of the member along the transverse bend line is done with a great force, and because portions of the side flanges are supported on their distal and proximal side, the material of the side flanges in the compression area plasticizes and flows into the closed perimeter opening, causing them to deform. Because the closed perimeter opening or openings are present, the side flanges are compressed in a more controlled manner, reducing cracking, wrinkling and thinning during the bending of the member along the transverse bend line.
|
