What are the common problems in machining large metal parts?

1. Burr: there is incomplete surplus material during punching or corner cutting, and burr will occur in the section of steel plate.
2. Concave convex: the material surface is abnormally convex or concave, which is caused by the mixing of foreign matters.
3. Roller stamp: caused by foreign matters attached to the cleaning roller or feeding roller (with a fixed pitch).
4. Sliding stamp: caused by the sliding of the roller, which occurs when it suddenly stops or accelerates.
5. Roll crushing may cause edge wrinkling: the guide roller of uncoiling line may cause wrinkling due to the small gap between the guide rollers on the die, which is caused by the imbalance of roll feeding.
6. Scratch: the main cause of scratches on parts. There are sharp scars on the mold or metal dust falling into the mold. The preventive measures are grinding the scars on the mold and removing metal dust.
7. Bottom crack: the main reason for the bottom crack of the part is that the material plasticity is poor or the die blank holder is too tight.
8. Wrinkles on the side wall: the main reason for wrinkles on the side wall of the part is that the thickness of the material is not enough, or the eccentricity occurs during the installation of the upper and lower molds, resulting in large clearance on one side and small clearance on the other.