Problems that often occur in the process of stamping and drawing dies
The stamping and drawing mold is an indispensable tool for abrasive tool manufacturers. During the drawing process of the product, there will be some problems of different sizes, and some problems may even cause the product to be scrapped. The manufacturer cannot deliver the goods, then these problems are what? How to avoid it?
During the stretching process of the stamping and drawing die, due to the excessive tangential stress in the surrounding edge part, the material loses stability, which makes the product form uneven wrinkles along the edge, which is called wrinkling. When the wrinkling is serious, it will also cause the material to be difficult to pass through the gap between the concave mold and the convex mold in the drawing process, increase the tensile deformation force, and even cause cracking. The method of preventing wrinkling in the process of stamping and stretching the mold can use a blank holder ring. Without affecting the subsequent processes of the product, put a circle of raised ribs around the material of the stamping and stretching mold and press the material around. The advantage is that the stretched product will be fuller and prevent wrinkles. And tensile cracking is also the second problem that occurs easily during the drawing process of the stamping and stretching die. During the process, when the tensile stress on the cylinder wall exceeds the strength limit of the material, the product of the stamping and stretching die will be cracked. Cracks generally appear at the wall of the barrel slightly above the fillet. This is related to the tensile properties of the material, the diameter and thickness of the material, the drawing coefficient, the fillet radius of the concave-convex die, the blank holder force, and the friction coefficient. Therefore, when stamping and drawing the die, the customer's product requirements can be met. If possible, make the fillets as large as possible, not too sharp. During stretching, the necessary lubrication is adopted, which is beneficial to the smooth progress of the stretching process and the tube wall thickness is improved. However, it must be noted that the lubricant can only be applied to the working surface of the die, and the surface where the die is in contact with the material must not be lubricated, because the friction between the die and the surface of the blank is a favorable friction, which can prevent the material from sliding and pulling. Cracked and thinned.