DIN 17175 Seamless steel pipes for high temperature applications. In the case of DIN 17175 St35.8 steel pipes, steels that have good mechanical properties at higher temperatures, up to 6 00 °C, even under long-term loads are called heat-resistant steels.
heat treatment temperature of DIN 17175 St35.8 Seamless Steel Tubes
Hot working is possible from 1100 to 850°C, and the temperature can be reduced to 750 °C during processing.
| Steel Grade | Thermal processing ℃ | Normalizing℃ | Tempering | ||
| Grade | Material number | Quenching temperature ℃ | Tempering temperature ℃ | ||
| St35.8 | 1.0305 | 1100 to 850°C | 900-930 | - | |
Chemical composition of DIN 17175 St35.8
| Standard | grade | Chemical composition | |||||
| C | Si | Mn | P,S | Cr | Mo | ||
| DIN 17175 | St35.8 | ≤0.17 | 0.10-0.35 | 0.40-0.80 | ≤0.030 | / | / |
Mechanical property of DIN 17175 St35.8
| Standard | grade | Tensile Strength(MPa) | Yield Strength(MPa) | Elongation(%) |
| DIN 17175 | St35.8 | 360-480 | ≥235 | ≥25 |
Dimensions Tolerance
| Project | Standard | Size range | Tolerance | |||
| Outer diameter | DIN17175 | Hot rolled steel pipe | OD ≤ 100mm | ± 0.75%( Min ± 0.5mm ) | ||
| OD> 100~ 320mm | ± 0.9% | |||||
| Cold drawn steel pipe OD ≤ 120mm | ± 0.6%( Min ± 0.25mm ) | |||||
| Wall thickness | DIN17175 | OD ≤ 130mm | WT ≤ 2Sn | +15%~-10% | ||
| WT > 2Sn~4Sn | +12.5%~-10% | |||||
| WT > 4Sn | ± 9% | |||||
| 130 < OD ≤ 320mm | WT ≤ 0.05OD | +17.5%~-12.5% | ||||
| 0.05OD < WT ≤ 0.11OD | ± 12.5% | |||||
| WT > 0.11OD | ± 10% | |||||


