Technological Process
Hot rolling (extruding seamless steel pipe): round tube blank → heating → piercing → three roll cross rolling, continuous rolling or extrusion → pipe stripping → sizing (or reducing) → cooling → blank tube → straightening → hydrostatic test (or flaw detection) → marking → warehousing. Cold drawn (rolled) seamless steel pipe: round tube billet → heating → perforation → heading → annealing → pickling → oil coating (copper plating) → multi pass cold drawing (cold rolling) → billet → heat treatment → straightening → hydrostatic test (flaw detection) → marking → warehousing.
Product Display
Chemical Composition
| Standard | Grade | Chemical Composition % | ||||||
| C | Si | Mn | P, S | Cr | Ni | Cu | ||
| GB/T8163 | 10 | 0.07-0.14 | 0.17-0.37 | 0.35-0.65 | ≤0.035 | ≤0.15 | ≤0.25 | ≤0.25 |
| 20 | 0.17-0.24 | 0.17-0.37 | 0.35-0.65 | ≤0.035 | ≤0.25 | ≤0.25 | ≤0.25 | |
| Q345 | 0.12-0.20 | 0.20-0.55 | 1.20-1.60 | ≤0.045 | / | / | / | |
Additional Condition
UT(Ultrasonic examination). AR(As Hot Rolled only). TMCP(Thermal Mechanical Control Processing). N(Normalied). Q+T(Quenched and Tempered). Z Direction Test(Z15,Z25,Z35). Charpy V-Notch Impact Test. The Third Party Test (such as SGS Test). Coated or Shot Blasting and Painting.
Mechanical Properties
| Standard | Grade | Mechanical Properties | ||
| Tensile Strength MPa | Yield Strength MPa | Elongation % | ||
| GB/T8163 | 10 | 335-475 | ≥205 | ≥24 |
| 20 | 410-550 | ≥245 | ≥20 | |
| Q345 | 490-665 | ≥325 | ≥21 | |
Mechanical Property of DIN 17175 St35.8 Seamless Steel Tubes
| Standard | Grade | Tensile Strength(MPa) | Yield Strength(MPa) | Elongation(%) |
| DIN 17175 | St35.8 | 360-480 | ≥235 | ≥25 |
Product Introduction