The plastic deformation hardens sharply during deep drawing, and it is easy to wrinkle during deep drawing, which requires a large blank holder force. ? The springback caused by bending and reverse bending of sheet metal at the corner of drawing die usually forms concave deformation on the side wall of the product. For products with high dimensional accuracy and shape requirements, it is necessary to increase the forming process. ? In addition, stainless steel is prone to sticking during stretching. The problem of adhesion tumor has been puzzling the customer's production site and bringing great trouble to the factory. Because the formation of adhesions involves tribology and other issues, there are many influencing factors.

? So from wire drawing oil's point of view, what can be done to prevent the occurrence of adhesive tumors?

? Why do adhesive tumors form? It is an indisputable fact in theory that the sheet metal is in direct contact with the die. Therefore, the first point in selecting a drawing lubricant is that the oil film in the drawing oil never breaks and plays a lubricating role in the sheet metal drawing process.

? With the addition of imported extreme pressure antiwear agent, the extreme pressure performance is excellent. Its main function is to improve the lubricating ability of lubricant to metal surface, strengthen the oil film strength and adsorption ability, and better lubricate the mold and product surface. 18 1-2963-9559

Besides wire drawing oil's choice, the mold is also a key issue. The material selection and heat treatment of the working part of the die and the surface treatment of the working part of the die will seriously affect its tensile effect.

There are many reasons for wrinkling in deep drawing, mainly in the following aspects:

(1) The drawing depth of stamping parts is too deep, which leads to the sheet metal flowing too fast and wrinkling. ?

(2) In the drawing process of stamping parts, the R angle of the female die is too large, which leads to the material can not be pressed by the male die in the drawing process, and the sheet metal flows too fast and wrinkles. ?

(3) The pressing rib of stamping parts is unreasonable, too small and incorrect, which can not effectively prevent the sheet metal from flowing too fast and forming wrinkles. ?

(4) The ejector pin pressure is too small, which leads to incomplete forming and wrinkling of stamping parts. ?

(5) The die positioning design is unreasonable, which leads to the stamping parts not being pressed up or the blank holder being too small, which leads to the stamping parts not being pressed up and wrinkling during the drawing process. ?

(6) The gap between the convex and concave dies is too large, which leads to the failure to press the material in the drawing process and wrinkles. ?

The above are the common causes of wrinkling in the drawing process of metal stamping parts, which need to be analyzed in detail, and the specific reasons should be found according to the specific conditions of stamping parts.

? The method to prevent wrinkling is to ensure that the die can hold down the material in the drawing process of metal stamping parts and ensure a reasonable sheet metal flow speed. When drawing stamping parts, the metal plate flows too fast.

May cause wrinkling; On the other hand, if the sheet metal flows too slowly, the stamping parts will crack. Setting drawbead on blank holder is an effective and practical method to adjust and control deformation resistance.

Drawbead can adjust the flow of material well, so that the flow resistance of each part of the material is uniform during drawing, and the amount of material flowing into the cavity is suitable for the needs of parts.

Prevent more wrinkling and less cracking. For curved surface drawing parts with complex shapes, especially those with small flanges, drawing ribs should be set to improve the radial tensile stress of drawing to control wrinkling;

The setting position of drawbead is in the position where the radial tensile stress is small, that is, the position where the sheet metal is easy to flow. For small flange parts, in order to set drawbead, some materials (process accessories) can be added appropriately.

Remove this part when trimming. For deep-drawn parts with great difference in drawing depth, the drawbead should be set in the part with less feed, so that too much material in this part can be organized to be pulled into the cavity of the female die, thus preventing wrinkling.