1)GB/T8163 Seamless Pipe Sizes (O.D. x W.T):21.3 mm-914mm x 2m-60m 2)Standard:GB/T8163 3)GB/T8163 Seamless Pipe Steel Grade:20#,16MN,Q345B 4)Surface:oiled or black painted to prevent rust 5)Marking:as per customer’s requirement Inner packing:Caps on two ends of every pipe Outer packing: Hexagonal shape bundles wrapped with strong steel trip or according to customers’requests.
Diamensional Tolerances Of GB/T8163 Seamless Pipe
| Types of steel tubes | Outer diameter | Wall thickness | ||
| Cold-rolled tubes | Tube sizes(mm) | Tolerances(mm) | Tube sizes (mm) | Tolerances(mm) |
| ＞30～50 | ±0.3 | ≤30 | ±10％ | |
| ＞50～219 | ±0.8％ | |||
| Hot-rolled tubes | ＞219 | ±1.0％ | ＞20 | ±10％ |
Mechanical Properties Of GB/T8163 Seamless Pipe
| Standard codes | Models of steel tubes | Tensite strength（MPa） | Yield strength（MPa） | Elongation（％） |
| GB/T8163 | 10 | 335～475 | ≥205 | ≥24 |
| 20 | 410～550 | ≥245 | ≥20 | |
| Q345 | 490～665 | ≥325 | ≥21 |
Chemical Composition Of GB/T8163 Seamless Pipe
| Standard codes | Models of steel tubes | Chemical compositions（％） | |||||||
| 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 | ≤0.035 | ≤0.15 | ≤0.25 | ≤0.25 |
| 20 | 0.17～0.24 | 0.17～0.37 | 0.35～0.65 | ≤0.035 | ≤0.035 | ≤0.25 | ≤0.25 | ≤0.25 | |
| Q345 | 0.12～0.20 | 0.20～0.55 | 1.20～1.60 | ≤0.045 | ≤0.045 | / | / | / | |
