United States · ASME
SB-338 Grade 7H
ASME SB-338
Chemical composition
| Element | min | max | Similar | Remarks |
|---|---|---|---|---|
| C | 0.08 | Product analysis tolerance +0.02% | Product analysis tolerance +0.02% | |
| Fe | 0.3 | Product analysis tolerance +0.15% | Product analysis tolerance +0.15% | |
| H | 0.015 | Product analysis tolerance +0.002% | Product analysis tolerance +0.002% | |
| N | 0.03 | Product analysis tolerance +0.02% | Product analysis tolerance +0.02% | |
| O | 0.25 | Product analysis tolerance +0.03% | Product analysis tolerance +0.03% | |
| Pd | 0.12 | 0.25 | Product analysis tolerance +/-0.02% | Product analysis tolerance +/-0.02% |
| Ti | Bal | Bal | ||
| Total Each | 0.1 | Product analysis tolerance +0.02% | Product analysis tolerance +0.02% | |
| Total Others | 0.4 |
Mechanical properties
| Heat treatment / condition | Yield strength | Tensile strength | Elongation | Reduction of area | Impact energy | Hardness |
|---|---|---|---|---|---|---|
| seamless steel tube, welded steel tube, annealed | ≤275 | ≤400 | ≤20 |
High/low temperature
| Condition | Temperature ℃ | min | Remarks |
|---|---|---|---|
| steel tubes | welded steel tubes annealed | 325 | 81.00 |
| steel tubes | welded steel tubes annealed | 300 | 87.00 |
| steel tubes | welded steel tubes annealed | 275 | 95.00 |
| steel tubes | welded steel tubes annealed | 250 | 107.00 |
| steel tubes | welded steel tubes annealed | 225 | 122.00 |
| steel tubes | welded steel tubes annealed | 200 | 139.00 |
| steel tubes | welded steel tubes annealed | 175 | 157.00 |
| steel tubes | welded steel tubes annealed | 150 | 176.00 |
| steel tubes | welded steel tubes annealed | 125 | 194.00 |
| steel tubes | welded steel tubes annealed | 100 | 212.00 |
| steel tubes | welded steel tubes annealed | 65 | 238.00 |
| steel tubes | welded steel tubes annealed | 40 | 276.00 |
| steel tubes | welded steel tubes annealed | -30 | 276.00 |
| Condition | Temperature ℃ | min | Remarks |
|---|---|---|---|
| steel tubes | welded steel tubes annealed | 350 | 170.00 |
| steel tubes | welded steel tubes annealed | 325 | 178.00 |
| steel tubes | welded steel tubes annealed | 300 | 190.00 |
| steel tubes | welded steel tubes annealed | 250 | 219.00 |
| steel tubes | welded steel tubes annealed | 200 | 250.00 |
| steel tubes | welded steel tubes annealed | 150 | 289.00 |
| steel tubes | welded steel tubes annealed | 100 | 340.00 |
| steel tubes | welded steel tubes annealed | 40 | 400.00 |
| steel tubes | welded steel tubes annealed | -30 | 400.00 |