1.Chemical Requirements
| N | C | H | Fe | O | Al | V | Pa | Mo | Ni |
Gr 1 | 0.03 | 0.08 | 0.015 | 0.20 | 0.18 | / | / | / | / | / |
Gr 2 | 0.03 | 0.08 | 0.015 | 0.30 | 0.25 | / | / | / | / | / |
Gr 3 | 0.05 | 0.08 | 0.015 | 0.30 | 0.35 | / | / | / | / | / |
Gr 5 | 0.05 | 0.08 | 0.015 | 0.40 | 0.20 | 5.5~6.75 | 3.5~4.5 | / | / | / |
Gr 7 | 0.03 | 0.08 | 0.015 | 0.30 | 0.25 | / | / | 0.12~0.25 | / | / |
Gr 9 | 0.03 | 0.08 | 0.015 | 0.25 | 0.15 | 2.5~3.5 | 2.0~3.0 | / | / | / |
Gr12 | 0.03 | 0.08 | 0.015 | 0.30 | 0.25 | / | / | / | 0.2~0.4 | 0.6~0.9 |