January 29, 2024
Reasons for surface scratches on curved parts:
1.When continuously bending soft materials such as copper and aluminum alloys, metal particles or slag are prone to adhere to the surface of the working area, causing significant scratches on the workpiece. In this case, the shape of the working area, lubricating oil, and other conditions should be carefully analyzed and studied to ensure that the billet does not have particles or slag, which may cause scratches.
2.When the bending direction is parallel to the rolling direction of the material, cracks will appear on the surface of the workpiece, causing a decrease in the surface quality of the workpiece. When bending in two or more parts, it is necessary to ensure that the bending direction is at a certain angle with the rolling direction as much as possible.
3.When the burr surface is used as the outer surface for bending, the workpiece is prone to cracks and scratches, so the burr surface should be used as the inner surface for bending.
4. The fillet radius of the concave mold is too small, and there are impact marks on the curved parts. Polishing the concave mold and increasing the fillet radius of the concave mold can prevent scratches on bent parts.
5. The gap between the convex and concave molds should not be too small, as a small gap can cause thinning and scratching. During the stamping process, it is necessary to constantly check the changes in the clearance of the mold.
6.When the depth of the convex mold entering the concave mold is too large, it will cause surface scratches on the part. Therefore, while ensuring that it is not affected by rebound, the depth of the convex mold entering the concave mold should be appropriately reduced.
7. In order to meet the accuracy requirements of the workpiece, it is often used in the bottom pressing bending die. During bending, the springs, positioning pin holes, support plates, and return holes on the pressing plate will be pressed into indentations, so adjustments should be made.