Factors Affecting Wrinkling Of Stamped Parts

Factors affecting wrinkling of stamped parts
(1) Influence of drawing depth
The distribution of material flow resistance along the die mouth is directly related to the drawing depth. At the concave and convex curve positions, excessive drawing depth can cause uneven distribution of deformation resistance and wrinkling, which should be avoided as much as possible.
(2) Adjusting the size of the blank holder force
When wrinkles are uniformly generated around the workpiece, it should be judged that the pressing force is insufficient, and the wrinkles can be eliminated by gradually increasing the pressing force. When stretching conical parts and hemispherical parts, most of the material is in a suspended state at the beginning of stretching. It is easy to produce side wall wrinkles, so in addition to increasing the blank holder force, it is also necessary to increase the pick-up stretching ribs to increase the radial tensile stress in the plate and eliminate wrinkles.
(3) Influence of the radius of the die fillet
If the radius of the die fillet is too large, the bending resistance of the blank flowing into the die through the die fillet is smaller. The smaller the bending resistance, the easier it is to cause wrinkling. The smaller the radius of the die, the greater the bending resistance of the bending deformation, the less likely it is to wrinkle, but it is easy to cause cracking and hair pulling of the workpiece.
Through a large amount of production practice experience, it has been proved that the main reason for the wrinkling of stamping parts is the accumulation of materials during the stretching process and the excessive speed of local material movement. When formulating practical solutions, the corresponding mechanism of the mold should be adjusted from the above aspects to achieve good results.