How do the L series correspond to the X series steel grades?
- Share
- Issue Time
- May 16,2026
The "L" series of GB/T 9711 corresponds to the "X" series of API 5L one by one, but the unit is different - the L series is in MPa (MPa) and the X series is in ksi (ksi). For example, L360 corresponds to X52 (360MPa ≈ 52ksi), L415 corresponds to X60, L485 corresponds to X70 and L555 corresponds to X80. The number of the steel grade number represents the minimum yield strength: X52 minimum yield strength is 52ksi, L360 minimum yield strength is 360MPa.