Product Introduction:
Standard GB9948-2013 Main steel grades: 10, 20, 12CrMo, 15CrMo
Usage:
Used for manufacturing furnace tubes, heat exchanger tubes, and pipelines in petroleum refineries
Dimensional Deviation
Technical parameters:
Types of steel pipes | Steel pipe size | Allowable deviation |
hot-rolled pipe | outside diameter | ≤159 | ±1.00% |
>159 | ±1.25% |
wall thickness | ≤20 | ±12.5% |
>20 | ±10.0% |
cold-drawn pipe | outside diameter | ≤30 | ±0.20 |
30~50 | ±0.30 |
>50 | ±0.8% |
wall thickness | ≤3 | +12%－10% |
>3 | ±10% |
Chemical composition and mechanical properties
standard | Steel 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) | Elongation rate (%) |
10 | 330～490 | ≥205 | ≥24 | 10 | 330～490 | ≥205 | ≥24 |
20 | 410～550 | ≥245 | ≥21 | 20 | 410～550 | ≥245 | ≥21 |
12CrMo | 410～560 | ≥205 | ≥21 | 12CrMo | 410～560 | ≥205 | ≥21 |
15CrMo | 440～640 | ≥235 | ≥21 | 15CrMo | 440～640 | ≥235 | ≥21 |
