| Defect in deep drawing cup | Reason | ||
|---|---|---|---|
| P | Orange peel on the surface of cup | 1 | No blank holding force |
| Q | Wrinkling at the flange of cup | 2 | Very small corner radius of the punch |
| R | Tearing at the bottom corner of cup | 3 | Large grain size in the blank material |
| S | Earring at the top edge of the cup | 4 | Anisotropy of the blank material |