What is the reason for hole diameter deviation in precision automotive stamping parts processing?

2024-05-07 08:13:26

When we use terminal molds for stamping processing, in order to avoid the stamping workpiece being damaged or unable to be used normally, we also need to pay attention to the following matters. The spacing between the inner lead pins must be kept correct and even. The embossing process will reduce this spacing, so the embossing depth must be controlled and the lateral recurvature of the lead pins must be suppressed.

The front section of the lead within the lead frame requires high flatness, and the flat area is at least 0.1MM (larger than three times the diameter of the gold wire), so an embossing process must be used. The high flatness requirements of the lead frame are beneficial to the stability and smoothness of subsequent project transportation. The corresponding strategy is to suppress the recurvature of the guide pin to a small amount and keep the recurve direction consistent when punching. Also, the lead frame material should be subjected to a stress relief process before stamping.

Deformations such as distortion or offset of the lead pins within the lead frame must be kept to a minimum, which is beneficial to the reliable operation of subsequent projects. The solution is to pay attention to the strong pressure design of the pressing plate in the mold, set the appropriate mold gap and functional components (punch and mother mold), keep the knife in good condition, and have high rigidity in the mold guide.

The position accuracy of the inner guide pin must be kept correct to facilitate reliable adhesion in subsequent projects. The corresponding strategy is to punch out the inner guide pin first and then punch out the outer guide pin. The stamping processing sequence must be properly designed, and the adjustment station should be designed during the stamping process. , to suppress the deviation of the lead frame lead position during stamping processing.

In daily precision stamping processing, you will encounter problems such as the punching size is too large or small, and the size of the punch is quite different.

When the punching edge wears, the tensile stress on the material increases, and the stamping parts tend to turn over and twist. When material turning occurs, the punching size will tend to be smaller.

The strong pressure exerted on the material by the processing of automotive stamping parts causes plastic deformation of the material, which will lead to larger punching holes. When the strong pressure is reduced, the punching size will become smaller.

The shape of the punch cutting edge. If the end is beveled or curved, the punched parts will not easily turn over or twist due to the slowed down punching force.

Precision metal stamping can produce workpieces with reinforced ribs, ribs, undulations or flanges that are difficult to manufacture by other methods to improve their rigidity. Due to the use of precision molds, the accuracy of the workpiece can reach micron level, with high repeatability and consistent specifications, and holes, bosses, etc. can be punched out. In the daily production of stamping parts, the punching size may be too large or too small (may exceed the specification requirements) and the size of the punch is greatly different. In addition to considering the design size, processing accuracy and In addition to factors such as blanking clearance, the above aspects should also be considered.