​Stamping Parts Wrinkling And Stacking

Stamping parts wrinkling and stacking

Defect description of stamping parts: Due to the large difference between the thickness direction of the sheet and the plane direction, the thickness direction is unstable. When the stress in the plane direction reaches a certain level, the thickness direction is unstable, resulting in wrinkling.

Causes of wrinkled stampings

(1) The stamping parts are piled up and wrinkled, and too much material enters the cavity of the die, causing wrinkles.
⑵ Instability and wrinkling of stamping parts:
I. The binding force in the thickness direction of the sheet is weak, resulting in wrinkling due to the instability of the compression flange.
II. Uneven stress is likely to occur in unevenly drawn parts, causing wrinkles due to instability.
(3) The R angle of the part is too large, so that the punch cannot hold the material during the drawing process, and the material flows too quickly and wrinkles are generated.
⑷The setting of the pressing ribs of the parts is unreasonable, or the pressing ribs are too small, which cannot effectively prevent the material from flowing too fast.
⑸ Where the product needs to add creases, the creases are not added, or the creases are too small, which causes the stamped parts to wrinkle during the drawing process.
⑹The gap between the upper and lower dies is too large, which causes the die to be unable to hold down the material during the drawing process, causing wrinkles.

Solutions for wrinkling of stamping parts

1. Product design:
1) Check the rationality of the original product model design.
2) Avoid the saddle shape of the product.
3) Add ribs to the wrinkled parts of the product.

2.Stamping process:
1) Reasonably arrange the process.
2) Check the rationality of the pressing surface and the drawing supplementary surface.
3) Check the rationality of drawing blanks, pressing force, and local material flow.
4) Relieve wrinkles with internal tendons.
5) Improve the pressing force, adjust the drawing ribs and stamping direction, increase the forming process, the thickness of the sheet material, and change the product and process shape to absorb excess materials.
⑶ Stamping material: In the case of satisfying the product performance, for some parts that are easy to wrinkle, the material with better formability is used.
The general method for correcting the wrinkling of stamping parts is to ensure that the mold can hold the material during the drawing process and ensure a reasonable and normal material flow speed: the material flows too fast during the drawing process, which may cause the part Wrinkling; If the material flows too slowly, it may cause the parts to crack.