ASTM A672 GR B60 CLASE 12 Welded Pipe – Technical Specifications
Overview
ASTM A672 covers electric-fusion-welded (EFW) steel pipes for high-pressure service at moderate and low temperatures. The Grade B60 Class 12 designation indicates:
– Carbon steel pipe with minimum yield strength of 60 ksi (415 MPa)
– Class 12 wall thickness (typically Schedule 80 or heavier)
– Designed for power plants, petrochemical, and gas transmission systems
Key Features
| Parameter | Details |
|———————-|————|
| Material | Carbon steel (similar to ASTM A516 Gr.60) |
| Manufacturing | Electric-fusion-welded (EFW) with filler metal |
| Heat Treatment | Stress-relieved or normalized |
| Pressure Rating | Suitable for ASME B31.1/B31.3 high-pressure systems |
| Temperature Range | -20°F to 650°F (-29°C to 343°C) (impact tested if used below -20°F) |
- Mechanical Properties (ASTM A672 GR B60)
| Property | Requirement |
|—————————-|—————-|
| Tensile Strength (Rm) | ≥ 70 ksi (485 MPa) |
| Yield Strength (Rp0.2) | ≥ 60 ksi (415 MPa) |
| Elongation (A5) | ≥ 18% |
| Impact Test (if required) | 20 ft-lb @ -50°F (-45°C) |
- Chemical Composition (Typical)
| Element | Composition (%) |
|————-|———————|
| C (Carbon) | ≤ 0.22 |
| Mn (Manganese) | 0.90–1.50 |
| P (Phosphorus) | ≤ 0.025 |
| S (Sulfur) | ≤ 0.025 |
| Si (Silicon) | 0.15–0.40 |
- Dimensions & Tolerances
– Sizes: NPS 16″ (DN 400) and larger (smaller diameters available per manufacturer)
– Wall Thickness (Class 12): Comparable to Schedule 80 (varies by diameter)
– Length: Single random (5–7 m) or double random (11–13 m)
- Testing & Inspection
– Hydrostatic Test: Mandatory (test pressure per ASTM A672)
– Non-Destructive Testing (NDT): RT (radiographic) or UT (ultrasonic) of welds
– Mechanical Tests: Tensile, bend, and impact (if specified)
– Visual/Dimensional Checks: Confirms compliance with ASTM tolerances
- Applications
✔ Power Plants – High-pressure steam/water lines
✔ Oil & Gas – Gas transmission, refinery piping
✔ Petrochemical – Process piping for corrosive fluids
✔ Cryogenic Service (with impact testing)
- Comparison with Similar Grades
| Feature | A672 GR B60 CL12 | A672 GR C60 CL12 | API 5L X60 |
|——————–|———————-|———————-|—————-|
| Yield Strength | 60 ksi (415 MPa) | 60 ksi (415 MPa) | 60 ksi (415 MPa)|
| Process | EFW | EFW | Seamless/Welded |
| Main Use | Power plants | High-pressure systems | Oil/Gas pipelines |
- Advantages
✅ High Strength-to-Cost Ratio – More economical than seamless pipes for large diameters
✅ Weldability – EFW construction ensures strong, reliable joints
✅ Custom Sizes – Available in heavy-wall (Class 12) for high-pressure needs
- Ordering Considerations
– Specify heat treatment (stress-relieved/normalized)
– If used below -20°F (-29°C), require impact testing
– Optional coatings (galvanizing, epoxy) for corrosion protection
ASTM A672 GR B60 CLASE 12 welded pipes are a cost-effective, high-strength solution for power, oil & gas, and chemical industries. Their EFW construction and Class 12 thickness make them ideal for high-pressure and low-temperature applications. Ensure compliance with ASTM A672 and specify testing/coating needs when ordering.
