Factors affecting the dimensional accuracy of stamping parts

Factors affecting the dimensional accuracy of stamping parts

The dimensional accuracy of stamping parts refers to the difference between the actual size and the design size of the stamping parts. The smaller the difference, the higher the accuracy. Ideally, the size of the blanking part is the same as the size of the die edge, and the size of the punched part is the same as the size of the punch edge.

In fact, due to the force exerted on the workpiece during punching, a certain elastic deformation will occur. After the punching is completed, the workpiece will undergo elastic recovery, which will cause the size of the blanking part and the die edge size, the punching part and the punch edge. The mouth size does not match, which affects the dimensional accuracy of the stamping parts.

There are many factors that affect the dimensional accuracy of stamping parts, such as punching clearance, die manufacturing accuracy, material properties and thickness, shape and size of stamping parts, etc. The main factor is the punching gap. When the gap between the convex and concave dies is too large, the drawing force on the material during the blanking process is greater, so the drawing deformation is large.

Stamping

After the punching is completed, the size of the blanking parts is reduced due to the elastic recovery of the material, while the size of the punching parts is increased. When the gap is too small, compression deformation occurs because the material is squeezed by the convex and concave dies. After punching, due to the elastic recovery of the material, the size of the blanking parts increases, while the size of the punching parts decreases.

The dimensional accuracy of stamping parts is also related to the nature and thickness of the material. Because the properties of the material directly determine the amount of elastic deformation of the sheet during the punching process, softer materials have smaller elastic deformation and smaller elastic recovery after punching, making the parts more precise and harder. The elastic deformation of the material is large, and the elastic recovery after punching is also large, resulting in low precision of the parts. When punching thin materials, the elastic arch is large and the elastic recovery is also large, resulting in low precision of the parts.

In addition, dimensional accuracy is also related to the shape and size of the part. The larger the size of the part and the more complex the shape, the more difficult it is to adjust the mold manufacturing, and it is difficult to ensure uniform mold clearance, so the greater the dimensional deviation. The influence of the above factors on the dimensional accuracy of stamping parts is discussed under the premise that the mold manufacturing accuracy is certain. If the manufacturing accuracy of the mold cutting edge is low, the accuracy of the punched parts cannot be guaranteed. Therefore, the manufacturing tolerances of the convex and concave die edge dimensions must be determined according to the dimensional accuracy requirements of the workpiece.