1. Edge burrs: Excessive, insufficient or uneven clearance in the die punching process, dull cutting edges of the punch and die, or poor punching conditions may all cause edge burrs.

2. Deformation and unevenness of the workpiece:

a. During the blanking process, the parts are subjected to significant stretching and bending forces, which can easily cause warping. The solution to this problem is to use a convex die and a stripper plate to firmly press the parts during the blanking process and to maintain sharp edges.

All of them can achieve good results.

b. When the shape of the part is complex, the shear force around the part is not uniform, thus generating a force from the periphery towards the center, causing the part to warp. The solution is to increase the clamping force.

c. When oil, air, or other substances are pressed onto the workpiece during the operation of the die and between the workpieces, the workpiece will warp. This is especially likely to occur with thin materials and soft materials. This can be prevented by applying oil evenly.

Install exhaust holes to eliminate warping.

3. Wrinkling:

The stretching depth of the stamped part is too deep, causing the sheet material to flow too rapidly during the material feeding process, resulting in wrinkling.

b. During the stretching process of the stamping parts, the R angle of the die is too large, causing the punch to fail to hold the material during the stretching. As a result, the sheet material flows too quickly, resulting in wrinkling.

c. The press-fit ribs of the stamped parts are improperly designed. The press-fit ribs are too small and their positions are incorrect. They fail to effectively prevent the sheet material from flowing too quickly, resulting in wrinkling.

d. The mold positioning design is unreasonable, resulting in the inability to hold the material during the stamping process or the insufficient size of the material holding edge, which leads to the inability to hold the material during the stretching process and causes wrinkling.

The solution to the problem of wrinkling is to adopt a reasonable die pressing device and properly utilize the stretch ribs.

4. Error in dimension accuracy:

In mold manufacturing, the dimensional accuracy of the cutting edge does not meet the standards, resulting in deviations in the dimensions of the finished products.

b. In the stamping production process, the workpiece undergoes deformation, resulting in the positioning surface of the next process not being fully aligned with the workpiece. During the stamping process, deformation occurs, which affects the dimensional accuracy.

c. Poor part positioning and unreasonable design led to the movement of the parts during the stamping process. Moreover, the design flaws of the parts resulted in inaccurate positioning, thereby affecting the dimensional accuracy.

d. For multi-process components, if the previous process is not adjusted properly or if the rounded corners are worn, resulting in uneven deformation, it can cause changes in the dimensions after the punching process. Regarding the above-mentioned factors that cause dimensional accuracy issues,

The reason is that we need to take necessary control measures, such as adopting appropriate stamping part shapes and tolerance grades, improving the manufacturing accuracy of molds, and designing rebound compensation mechanisms, etc.

5. Bruises:

a. There are impurities on the material surface. During the stamping process, check if there are any impurities on the material surface. If there are, use an air gun and a rag to clean them up.

b. There are foreign objects on the mold surface. Use tools to remove the foreign objects from the mold surface. Select an appropriate lower mold gap based on the thickness of the sheet material.

c. The mold is magnetically coated. By changing the processing sequence, the workpiece is processed from the outside to the inside and row by row. First, the edges are cut (trimmed), then the mesh holes are punched. For special forming stamping, there may be deformation.

It might be due to excessive pressure. The springs in the mold need to be replaced.

d. The pressurized oil does not meet the requirements. Replace the current pressurized processing oil with a dedicated pressurized oil that contains sulfur-based extreme pressure additives.

6. Scratches: The main cause of scratches on the parts is the presence of sharp scars on the mold or the entry of metal dust into the mold. The preventive measure is to grind off the marks on the mold and clean up the metal dust.

7. Bottom crack: The main causes of cracks at the bottom of the part are poor material plasticity or the mold's draft ring being pressed too tightly. The preventive measure is to replace with a material of better plasticity or to loosen the draft ring.

8. Side wall wrinkling: The main cause of side wall wrinkling on the part is that the material thickness is insufficient when the upper and lower molds are installed (if the difference is relatively small, the thickness can be slightly reduced) or there is eccentricity. This results in a larger gap on one side.

The gap on the other side is smaller. The preventive measure is to immediately replace the material and re-adjust the mold.