ASTM A671 — Low-temperature electrofusion welded steel pipe
Grades
Gr.CC60, Gr.CC65, Gr.CC70, Gr.CM65, Gr.CM70, Gr.CJ60, Gr.CJ65, Gr.CJ70
Chemical composition and mechanical properties
| Grade | Chemical composition | Mechanical properties |
|---|---|---|
| Gr.CC60 | C≤0.21, Mn 0.60-0.90, P≤0.030, S≤0.030, Si 0.13-0.32 | Rm ≥415 MPa, Rp0.2 ≥220 MPa, A≥21%, Killed steel |
| Gr.CC65 | C≤0.21, Mn 0.60-0.90, P≤0.030, S≤0.030, Si 0.13-0.32 | Rm ≥450 MPa, Rp0.2 ≥240 MPa, A≥19%, Killed steel |
| Gr.CC70 | C≤0.21, Mn 0.60-0.90, P≤0.030, S≤0.030, Si 0.13-0.32 | Rm ≥485 MPa, Rp0.2 ≥260 MPa, A≥17%, Killed steel |
Application scope
ASTM A671 specifies electrofusion welded steel pipes for use under normal and cryogenic conditions, including multiple grades such as CC, CM, and CJ series. The standard uses electrofusion welding to produce large-diameter steel pipes, balancing strength and low-temperature toughness. It is suitable for welded pressure piping systems, serving the manufacturing of cryogenic fluid transport pipelines and providing a basis for material selection for pressure vessels and pressure pipelines.
Typical applications
It is commonly used in the manufacture of large-diameter water pipelines, petrochemical process pipelines, and inlet and outlet pipes of cryogenic storage tanks. Electrofusion welding facilitates the manufacture of large-diameter steel pipes, and the combination with killed steel plates ensures good toughness. It is suitable for pressure pipelines and large-diameter connections and piping systems that transport fluids under normal pressure to cryogenic conditions, and is widely used in the pressure vessel and pressure pipeline industry.
