Solutions for Problems in the Sheet Metal Processing Bending Technology

Sheet metal processing is just a series of processes such as bending, riveting, and welding of metal materials. 

The following is for the problems and solutions encountered in the sheet bending process.

Problem 1: The bending edge of sheet metal processing is not straight and the size is unstable.

Causes:

1. The design process does not arrange crimping or pre-bending

2. Insufficient material pressure

3. The rounded corners of the convex and concave molds wear asymmetrically or the bending force is uneven

4. The height dimension is too small.

Solution:

1. Set crimping or pre-bending process

2. Increase the pressing force

3. Uniform gap between convex and concave molds, rounded corners and polished

4. The height size cannot be less than the minimum limit size

Problem 2: The outer surface of the sheet metal press parts is scratched after bending

Causes:

1. The surface of the raw material is not smooth

2. The bending radius of the punch is too small

3. The bending gap is too small

Solution:

1. Improve the finish of convex and concave molds

2. Increase the bending radius of the punch

3. Adjust the bending gap

Problem 3: There are cracks in the bending corners of sheet metal processing such as automotive sheet metal fabrication

Causes:

1. The inner radius of the bend is too small.

2. The material pattern is parallel to the bending line

3. The burr of the blank faces outwards

4. Poor metal plasticity

Solution:

1. Increase the bending radius of the punch

2. Change the blanking layout

3. Turn the burr into the fillet of the part

4. Anneal or use soft materials

Question 4: Hole deformation caused by bending of sheet metal processing

Cause:

When using elastic bending and positioning with holes, the outer side of the bending arm is pulled due to friction between the surface of the die and the outer surface of the workpiece, which deforms the positioning hole.

Solution:

1. Use shape bending

2. Increase the pressure of the ejector plate

3. Add pitting grid pattern on the top plate to increase the friction and prevent the parts from slipping when bending

Question 5: Thinning of the extruded material on the curved surface of sheet metal processing

Causes:

1. The fillet of the die is too small

2. The gap between the convex and concave molds is too small

Solution: 

1. Increase the fillet radius of the die

2. Correct the gap between convex and concave molds