| Metal | Chemical Composition | ||
| Elbow (%) | Welding joint (%) | Tube (%) | |
| Cr | 0.03 | 0.05 | 0.03 |
| Mn | 0.79 | 1.19 | 0.92 |
| Mo | 0.02 | <0.01 | <0.01 |
| Ni | 0.08 | 0.02 | 0.03 |
| Si | 0.31 | 0.62 | 0.19 |
| C | 0.195 | 0.043 | 0.163 |
| S | 0.003 | 0.024 | 0.002 |
| P | 0.018 | 0.023 | 0.022 |
| Fe | 98.60 | 97.96 | 98.66 |