Petroleum Cracking Tubes
Standard
GB9948-2013
Main steel grades: 10, 20, 12CrMo, 15CrMo
Uses
Used for manufacturing furnace tubes, heat exchanger tubes and pipelines in petroleum refineries
Dimensional Deviation
| Tube Type | Tube Dimension | Size Range | Allowable Deviation |
|---|---|---|---|
| Hot Rolled Tube | Outer Diameter | ≤159 | ±1.00% |
| >159 | ±1.25% | ||
| Wall Thickness | ≤20 | ±12.5% | |
| >20 | ±10.0% | ||
| Cold Drawn Tube | Outer Diameter | ≤30 | ±0.20 |
| 30~50 | ±0.30 | ||
| >50 | ±0.8% | ||
| Wall Thickness | ≤3 | +12%－10% | |
| >3 | ±10% |
Chemical Composition & Mechanical Properties
Chemical Composition
| 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
| Steel Grade | Tensile Strength (MPa) | Yield Strength (MPa) | Elongation (%) |
|---|---|---|---|
| 10 | 330～490 | ≥205 | ≥24 |
| 20 | 410～550 | ≥245 | ≥21 |
| 12CrMo | 410～560 | ≥205 | ≥21 |
| 15CrMo | 440～640 | ≥235 | ≥21 |