Factors affecting the dimensional accuracy of stamping parts

The dimensional accuracy of stamping parts refers to the difference between the actual size of the stamping part and the design size. The smaller the difference, the higher the accuracy. In an ideal situation, the size of the blanking piece is the same as the size of the die edge, and the size of the punching piece is the same as the die edge size. In fact, due to the force of the workpiece during punching, a certain elastic deformation occurs. After the punching is completed, the workpiece will undergo elastic recovery, which will cause the size of the blanking piece and the size of the die edge, the punching piece and the punch edge The inconsistency of the mouth size affects the dimensional accuracy of the stamping parts. There are many factors that affect the dimensional accuracy of stamping parts, such as blanking gap, die manufacturing accuracy, material properties and thickness, shape and size of stamping parts, etc. The main factor is the blanking gap. When the gap between the convex and concave dies is too large, the drawing effect of the material during the punching process is greater, so the drawing deformation is large. After the punching is finished, the size of the blanking part is reduced due to the elastic recovery of the material, while the size of the punching part is increased. When the gap is too small, compression deformation occurs due to the extrusion of the material by the convex and concave dies. After punching, the size of the blanking piece increases due to the elastic recovery of the material, while the size of the punching piece decreases. The dimensional accuracy of stamping parts is also related to the nature and thickness of the material. Because the nature of the material directly determines the amount of elastic deformation of the sheet during the blanking process, softer materials have a smaller amount of elastic deformation, and the amount of elastic recovery after punching is also smaller, making the parts more accurate and harder. Material, the amount of elastic deformation is large, and the elastic recovery after punching is also large, so that the precision of the part is low. When the thin material is blanked, the elastic arch and the elastic recovery are also large, so that the precision of the part is low. In addition, dimensional accuracy is also related to the shape and size of parts. The larger the size of the part, the more complex the shape, the more difficult it is to adjust the mold manufacturing, and the mold gap is not easy to ensure uniformity, so the greater the deviation of the size. The influence of the above factors on the dimensional accuracy of stamping parts is discussed under the premise of certain mold manufacturing accuracy. If the manufacturing precision of the die edge is low, the precision of the punched parts cannot be guaranteed. Therefore, the manufacturing tolerance of the knife edge size of the convex and concave molds should be determined according to the dimensional accuracy requirements of the workpiece. Previous post: Analysis of the whole process of blanking and deformation, don't understand it after reading it