API 5L (钢板) — Pipeline steel plate
Grades
Gr.A, Gr.B, X42, X46, X52, X56, X60, X65, X70, X80, X90, X100, X120 (PSL1/PSL2)
Chemical composition and mechanical properties
| Grade | Chemical composition | Mechanical properties |
|---|---|---|
| Gr.A | C≤0.14, Mn≤0.90, P≤0.035, S≤0.040 | Rm 310-415 MPa, Rp0.2 ≥165 MPa, A≥27% |
| Gr.B | C≤0.17, Mn≤1.20, P≤0.035, S≤0.040 | Rm 345-450 MPa, Rp0.2 ≥185 MPa, A≥25% |
| X42 | C≤0.26, Mn≤1.40, P≤0.025, S≤0.015, Si (no requirements), Cr≤0.40, Cu≤0.40, Ni≤0.40, Mo≤0.15, V≤0.06, Nb+V≤0.06, Ti≤0.04, B≤0.001, N≤0.012 | Rm ≥415 MPa, Rp0.2 ≥290 MPa, A≥21% (gauge length 50mm), PSL2 has impact requirements. |
Application scope
API 5L (steel plate) specifies steel plates and strips for use in the manufacture of long-distance oil and gas pipelines. It is the raw material for straight seam submerged arc welded (LSAW) and spiral welded (SSAW) pipes, and is delivered in two quality grades: PSL1 and PSL2. The strength increases from Gr.B to X70 and X80, with PSL2 offering additional impact toughness and stricter composition control, balancing high strength, toughness, and weldability.
Typical applications
Primarily used as raw material for pipeline production, it is employed in the manufacture of large-diameter oil and gas transmission pipes such as straight seam submerged arc welded pipes (LSAW) and spiral welded pipes (SSAW). It is widely used in long-distance transmission trunk lines, gathering and transmission networks, and station process pipelines for crude oil, refined oil, and natural gas. High-grade steel plates can be used in demanding pipelines such as those operating under high pressure, large capacity, and extremely cold conditions, serving as the foundational material for long-distance pipeline projects.
