1. Raw edges of punched pieces generated during blanking.  It is necessary to study the blanking edge and check whether the blanking clearance is reasonable.  Due to instability of Stamping Parts during bending.  The main needle is bent in U-shape and V-shape.  In order to deal with this problem, the key points to solve the problem are to guide the stamping part before bending, guide the stamping part during bending, and press the material during bending to prevent the stamping part from slipping during bending.  The rough edges of punched pieces produced during blanking.  It is necessary to study the blanking edge and check whether the blanking clearance is reasonable.

2. When the cutting edge is worn, the tensile stress on the material increases and the tendency of Plastic Injection Parts to turn over and twist increases.  When turning over the material, the punching size will become smaller.  The strong pressure on the material will cause plastic deformation of the material, which will lead to larger punching size.  However, when the strong pressure is reduced, the punching size will become smaller.

3, punch edge end shape.  If the end is beveled or curved, because the blanking force is relieved, the punching piece is prone to material turning and smearing, thus the punching size will increase.  When the end of the punch is flat (without bevel or arc), the punching size will be relatively smaller.  In the actual operation, the specific title problem should be specifically analyzed so as to find out the countermeasures to solve the problem.