GB 8163 steel pipe

GB 8163 steel pipe is a seamless steel pipe for fluid transportation (GB/T8163-2018), which is a general seamless steel pipe for conveying water, oil, gas and other fluids.

GB 8163 steel pipe
Diamensional Tolerances
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(%)
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(%)
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 / / /
Additional Condition


Seamless pipe Specification, standard and identification

Seamless pipes are extensively applied for the nuclear device, gas, petrochemical, ship building and boiler industries. Seamless pipes dominates 65% of market share in Chinese boiler industry.