Problem 1: The bent edge is not straight and the size is unstable
reason:
1. The design process did not arrange for wire pressing or pre bending
2. Insufficient material pressing force
3. Uneven wear or uneven bending force on the rounded corners of convex and concave molds
4. The height dimension is too small
terms of settlement:
1. Design line pressing or pre bending process
2. Increase material pressure
3. Uniform clearance between convex and concave molds, rounded corners polished
4. The height dimension cannot be less than the minimum limit dimension
Question 2: Scratches on the outer surface of the workpiece after bending
reason:
1. The surface of the raw material is not smooth
2. The bending radius of the convex mold is too small
3. The bending gap is too small
terms of settlement:
1. Improve the smoothness of convex and concave molds
2. Increase the bending radius of the convex mold
3. Adjust the bending gap
Question 3: There are cracks in the bending angle
reason:
1. The inner radius of the bend is too small
2. The material grain is parallel to the bending curve
3. The burrs on the blank face outward
4. Poor plasticity of metals
terms of settlement:
1. Increase the bending radius of the convex mold
2. Change the material layout
3. Burrs are rounded inside the workpiece
4. Annealing or using soft materials
Question 4: Bending causes hole deformation
reason:
When using elastic pressure bending and hole positioning, the outer side of the bending arm is subjected to tension due to friction between the concave mold surface and the outer surface of the workpiece, causing deformation of the positioning hole.
terms of settlement:
1. Adopting shape bending
2. Increase the pressure on the top sheet
3. Add a grid pattern of pockmarks on the top sheet to increase friction and prevent the workpiece from slipping during bending
Problem 5: Thinning of extruded material on curved surfaces
reason:
1. The rounded corners of the concave mold are too small
2. The clearance between the convex and concave molds is too small
terms of settlement:
1. Increase the fillet radius of the concave mold
2. Correct the clearance between the convex and concave molds
Question 6: The end face of the component is bulging or uneven
reason:
1. When bending, the outer surface of the material undergoes shrinkage deformation due to tension in the circumferential direction, while the inner surface undergoes elongation deformation due to compression in the circumferential direction, resulting in bulging of the bent end face along the bending direction.
terms of settlement:
1. The convex and concave molds of the workpiece should have sufficient pressure in the final stage of stamping
2. Create a concave mold fillet radius that corresponds to the outer fillet of the component
3. Add process improvement
Question 7: Uneven bottom of concave parts
reason:
1. The material itself is uneven
2. The contact area between the top plate and the material is small or the top material force is insufficient
3. There is no top material device inside the concave mold
terms of settlement:
1. Leveling materials
2. Adjust the top material device to increase the top material force
3. Add top material device or calibration
4. Additive shaping process