1. Wrinkle and stacking

Wrinkle is one of the most important and difficult problems in stamping production. The wrinkling defect will cause many undesirable consequences, and it will also cause overlap when severe. Wrinkles will have a severe impact on the appearance of the part, especially after painting. Severe wrinkles will make the part unable to be repaired and cause the part to be scrapped.

Reason: In the process of sheet metal stamping, the material activity is unbalanced, and the extrusion occurs and cannot be absorbed and eliminated.

Processing idea: balance sheet activity speed.

Solution: (1) Burning and welding to increase the drawbead and increase the movement resistance of the sheet; (2) Do strong pressure treatment on the wrinkled part to reduce the surface gap; (3) Change the shape of the drawbead, such as changing the round bar to square Rebar, or change the size of the drawing bead; ⑷Add the size of the blanking piece to increase the effect of the blank holder.

Temporary production methods: (1) Increase the pressing force of the press; (2) Pad tape at relevant places; (3) Adjust the balance weight, cut some balance weight gaskets, and add part of the sheet material movement resistance.

2. Cracks and wound lines (neck shrinkage)

Cracking usually occurs when new molds or sheet materials are debugged. Cracking directly leads to the scrapping of parts. Strains are the ultimate manifestation of parts cracking. After coating and baking, the material stress is released, which may still cause parts to crack. Therefore, In the process of stamping and production, the strain on the finished part must be eliminated.

Reason: Due to the smooth movement of the sheet material, the tensile deformation of the sheet material during the stamping process exceeds the elongation requirement of the material itself, resulting in cracking of the stamping part.

Processing idea: improve the speed of sheet material activity.

Solution: (1) Burning and welding to lower the drawbeads and reduce the resistance of sheet metal feeding; (2) Improve the surface finish; (3) Add piercing knives and increase part of the supply of sheet metal activities; (4) Change the shape of the drawbeads; ⑸ reduce the sheet material Edge scale.

Temporary production methods: (1) Apply lubricating oil to the cracked or damaged line; (2) Properly reduce the blank holder force; (3) Adjust the balance weight and add some balance weight gaskets to reduce the movement resistance of some sheets.