(1) the blank positioning should be accurate and reliable, and can be used for the hole location of the blanks to prevent the deviation of the blank in the process of deformation.
(2) the die structure should not interfere with the rotation and movement of the blanks in the bending process, and avoid the deformation of the billet during the bending process.
(3) the die structure should be able to ensure that the horizontal direction of the wrong shift force balance between the upper and lower dies.
(4) in order to reduce the rebound, the bending part of the stroke should be corrected in the mold.
(5) bending springback amount larger material, the structure of the mold must be consider the convex and concave mold processing and test mode for the possibility of a correction.