Zinc Plated Support

How to deal with wrinkling during steel plate stamping?

1. The principle of wrinkling phenomenon

In the production process of steel products, the phenomenon of surface wrinkling and unevenness of the billet during stamping is a common stamping defect. This not only causes waste of raw materials, but sometimes also increases subsequent scrap, such as wrinkling of automotive stamping parts, which can directly lead to poor welding quality or even cracking of welding points during the subsequent welding process. So, how does wrinkling occur?

When the sheet metal undergoes stamping deformation, it is subjected to tensile stress in the plane tensile direction and compressive stress in the plate thickness direction. When the compressive stress in the plate thickness direction is much greater than the stability limit of the material, wrinkling occurs in the sheet metal. Under certain pressure, the thinner the sheet, the easier it is to wrinkle. At the same time, during the machining process, the maximum tangential compressive stress occurs along the edge of the flange, which means that the wrinkling on the outer edge is most pronounced.

2. Reasons for wrinkling and corresponding solutions

The main reasons for product wrinkling are found in three aspects:

(1) In terms of component design

Is the product model reasonable enough to consider molding issues, and is the setting of pressure bars too small? Do you need to add wrinkle absorbing ribs to areas that are prone to wrinkling?

Solution: Increase the pressure bar or change the layout of the pressure bar. Add wrinkle absorbing ribs to the waste section.

(2) In terms of process design

a. The pressure surface is loose inside and tight outside

Solution: Grinding and pressing the material surface.

b. The shape of the supplementary surface for pressing material is unreasonable

Solution: Modify the shape of the material filling surface to avoid uneven material flow caused by its fixed shape.

c. The reason for the blank. The blank is too small or improperly positioned in the mold

Solution: Increase the size of the blank. Improve the positioning of the blank on the mold, so that the mold can accurately press the material.

d. The pressing force is too small

Solution: Increase the pressure on the top rod.

e. The gap between the upper and lower molds is too large

Solution: Adjust the gap.

f. The fillet radius of the concave die is too large, causing the convex die to be unable to press down on the material

Solution: Reduce the fillet radius.

g. Lubricating oil applied too thick and too much

Solution: Follow the requirements of the operating regulations to apply oil and ensure the correct position and amount of oil applied

3. In terms of materials

The yield strength of the material did not meet the standard, and the material was too soft.

Solution: Use materials with good formability while ensuring product performance.