December 4, 2023
The parts are warped and uneven:
1. Large blanking gap
If the gap is too large, the tensile and bending forces of the workpiece will be large during the punching process, and warpage will easily occur. The improvement method can be to press the punch and the clamping plate tightly during punching, and keep the cutting edge sharp, which will achieve good results.
2. The die hole has a reverse taper
When the workpiece passes through a small-sized part, the outer periphery will be compressed toward the center, resulting in bending.
3. Warpage caused by the structural shape of the part
When the shape of the workpiece is complex, the shear force around the workpiece is uneven, thus generating a force from the periphery to the center, causing the workpiece to warp. The solution is to increase the pressing force.
4. Warpage caused by internal stress in the material
The internal stress generated during rolling and coiling of the material will move to the surface after blanking, and the workpiece will warp. The solution is to level it with a leveler when uncoiling.
5. Warpage due to oil, air and poor contact
When there is oil, air, etc. between the die and the part, or between the part and the part, which presses the part, the part will warp, especially thin and soft materials. However, if you apply oil evenly and install vents, you can eliminate warping.
There are debris on the surface between the part and the die, which can easily cause the part to warp.
Poor contact surface during punching can also cause warping.