What are the factors for wrinkling of precision metal stamping parts? 「Hardware」_

In the stamping process of precision metal stamping parts, wrinkles sometimes appear, causing the workpiece to be scrapped. What's the reason? Let the hardware author tell everyone! The reasons for wrinkling of precision metal stamping parts are: 1. Too much lubricating oil or frequent brushing. Lubricating oil should be used, but not too much; and the brushing position is improper. 2. The blank holder force is not enough, and the blanking surface gap is not suitable for the problem of 'loose inside and tight outside'. Improper stamping direction of the workpiece. 3. The test blank is too soft, the material strength is low, and the blank size is too small to hold the material. The positioning of the blank is unstable, which leads to the partial pressure of the material, and the improper shape of the material pressing surface, resulting in uneven feeding. The wrinkling phenomenon not only causes the workpiece to be scrapped, but also affects the cost of processing precision metal stamping parts and the waste of raw materials.