What is API 5L GR B material?
API5LGrB seamless steel pipes are made from high-quality carbon steel and manufactured into seamless pipe bodies through hot rolling or cold drawing processes. They are widely used in onshore and subsea oil and gas transportation projects.
What is the difference between API 5L GRB and A106 GRB
| Comparison Item | API 5L Gr.B (Oil & Gas Pipeline) | ASTM A106 Gr.B (High-Temp Service) |
|---|---|---|
| Governing Standard | API SPEC 5L | ASTM A106 |
| Operating Temp | -29°C ~ 427°C | -29°C ~ 650°C (short-term 700°C) |
| Chemical Composition | C≤0.28%, Mn≤1.25%, S≤0.03% | C≤0.30%, Mn=0.29-1.06%, S≤0.035% |
| Mechanical Properties | Tensile≥414MPa, Yield≥241MPa | Tensile≥415MPa, Yield≥240MPa |
| Primary Applications | Oil/Gas transmission pipelines | Power plant steam lines, boiler systems |
| Special Requirements | Low-temp impact test (-46°C) | High-temp strength test (≥400°C) |
| NDT Requirements | Optional (by PSL level) | Mandatory hydro test (1.5x design pressure) |
| Corrosion Resistance | H₂S stress corrosion test (NACE MR0175) | Not required |
| Pipe Type | Seamless/welded (PSL2) | Seamless only |
Chemical Composition of API 5L Grade B Carbon Steel Seamless Pipe
- Karbon (C): Maksimum 0,28%
- Mangan (Mn): 1,20% maksimum
- Fosfor (P): 0,030% maksimum
- Sulfur (S): 0,030% maksimum
- Silikon (Si): 0,40% maksimum
Mechanical Properties of API 5L Grade B steel pipes used for transmission pipeline systems
- Tensile Strength : Minimum 415 MPa
- Yield Strength : Minimum 245 MPa
- Elongation : Varies depending on pipe thickness, but typically around 23%
Test and inspection
1. Non-Destructive Testing (NDT)
Full-coverage ultrasonic testing (UT), supplemented by eddy current or magnetic flux leakage (EMI/MFL).
Per product specifications: Compliant with API SPEC 5L 46th Edition, UT class L2.
2. Physical & Chemical Tests
Tensile test: Elongation ≥22%, hardness ≤22 HRC.
Charpy V-notch impact test (critical for low-temp performance):
-20℃ average of three specimens ≥20 J (as referenced in technical encyclopedias).
3. Dimensional Tolerances
Outer diameter: ±0.75% to ±1.25%
Wall thickness: +12.5% / -10%
Vendor note: "+Tolerance Control Technology" ensures pressure safety margins.
API 5L GRB seamless steel pipe line factory
