Stamping tensile wrinkled reason and solution

Factors influencing stamping wrinkling and solution ( 1) Tensile depth influence the distribution of material flow resistance along the concave die in tensile depth has a direct relationship. Position, concave and convex outside the curve drawing depth is too large can cause the uneven distribution of deformation resistance, wrinkle formation, should avoid as far as possible. （ 2) Adjust the size of the blank holder force when wrinkles around the parts even produce, should determine the force that press a material shortage, increase the force that press a material can gradually get rid of wrinkles. When stretching taper and hemispherical parts, stretching at the beginning of most of the material in a suspended state. Easy generation side wall wrinkling, so in addition to increase the blank-holder force, also should be adopted to increase pick up common clubmoss radial tensile stress to increase the plate and get rid of wrinkles. （ 3) Die fillet radius of the effect of die corner radius is too large, blank to flow through the die fillet in the concave die is to produce the smaller the bending deformation of bending resistance. The smaller the bending resistance, the more likely to cause the occurrence of wrinkling. Small die radius bending deformation of bending resistance is larger, the more not easy corrugate, but easy to cause the cracking and galling parts. Through a lot of production practice experience proves that the stamping parts of the main causes of wrinkling, for the accumulation of material in the drawing process and local material movement speed too fast. When making practical solutions, from the above into consideration mold of the corresponding adjustment mechanism, will obtain good effect. The measures to prevent wrinkle pressing method is the way to prevent wrinkling is to guarantee the metal stamping parts in the process of stretching die to pressure, guarantee the reasonable flow sheet. Stamping parts in the sheet metal flow during a stretch too fast, can cause wrinkles; Sheet metal flow, on the other hand, too slow, can be caused by stamping craze. （ 1) The reasonable pressure device when using pressure device, pressure device will be tightly pressed on the blank deformation part, and the effect of pressure force, in order to prevent the flange part of the arch and cause wrinkles. The size of the force that press a material to the right. Pressure units are divided into two categories, elastic pressure and rigid material. The elastic device is suitable for the shallow drawing, rigid device is suitable for deep drawing. （ 2) Reasonable use drawbead on the pressure is expected to set the drawbead is an effective adjustment control deformation resistance and the use of the method. Drawbead well adjust the flows of material, make the material of each part in the process of stretching uniform flow resistance, make the material into the cavity quantity is suitable for the need of the parts, to prevent more wrinkle, less cracking phenomenon. For complex shape surface tensile), especially in smaller tensile flange, drawbead should be set up, in order to improve the radial tensile stress of the tensile wrinkle to control; The drawbead setting position on the radial tensile stress of the smaller parts, namely the part of the sheet metal liquid. For small flange parts, in order to set the drawbead, can be appropriately increase some materials ( Process supplementary material) When, trimming, to get rid of this part again. For drawing a tensile depth differ big, drawbead should be set at the site of the feed and less, so that it can to block the part too much material to pull people die cavity, so as to prevent wrinkles.