Seamless Steel Tubes For Petroleum Cracking Supplier-GNEE
- Standard
GB9948-2013 Grade：10,20,12CrMo,15CrMo
- Uses
Used in the manufacture of furnace tubes, heat exchanger tubes and pipes for petroleum refineries
- Deviation
| Types | Size | Tolerance | |
| Hot rolled pipe | outer diameter | ≤ 159 | ± 1.00% |
| > 159 | ± 1.25% | ||
| Wall thickness | ≤ 20 | ± 12.5% | |
| > 20 | ± 10.0% | ||
| Cold drawn tube | outer diameter | ≤ 30 | ± 0.20 |
| 30~50 | ± 0.30 | ||
| >50 | ±0.8% | ||
| Wall thickness | ≤ 3 | + 12%- 10% | |
| > 3 | ± 10% | ||
- Chemical composition, mechanical properties
| Standard | Grade | Chemical composition (%) | ||||||
| C | Si | Mn | Ni | Cr | Mo | P.S | ||
| GB9948 | 10 | 0.17 ～ 0.14 | 0.17 ～ 0.37 | 0.35 ～ 0.65 | ≤ 0.25 | ≤ 0.15 | / | ≤ 0.035 |
| 20 | 0.17 ～ 0.24 | 0.17 ～ 0.37 | 0.35 ～ 0.65 | ≤ 0.25 | ≤ 0.25 | / | ≤ 0.035 | |
| 12CrMo | 0.08 ～ 0.15 | 0.17 ～ 0.37 | 0.40 ～ 0.70 | ≤ 0.30 | 0.40 ～ 0.70 | 0.40 ～ 0.55 | ≤ 0.035 | |
| 15CrMo | 0.12 ～ 0.18 | 0.17 ～ 0.37 | 0.40～ 0.70 | ≤ 0.30 | 0.80 ～ 1.10 | 0.40 ～ 0.55 | ≤ 0.035 | |
| Mechanical properties | Tensile Strength (MPa) | Yield Strength (MPa) | Extensibility(%) | |||||
| 10 | 330 ～ 490 | ≥ 205 | ≥ 24 | |||||
| 20 | 410 ～ 550 | ≥ 245 | ≥ 21 | |||||
| 12CrMo | 410 ～ 560 | ≥ 205 | ≥ 21 | |||||
| 15CrMo | 440 ～ 640 | ≥ 235 | ≥ 21 | |||||
20# pipe
