Professional Overview of API 5L X70 (L485) Ultra-High Strength Line Pipe Steel

API 5L X70 (L485) is an ultra-high strength pipeline steel with 485 MPa yield strength, used in world-class long-distance and high-pressure transmission.

X70 delivers extremely high strength, low-temperature toughness, corrosion resistance, and crack resistance. It performs well in deserts, cold climates, offshore, and deep-sea environments.

Its chemical composition follows a strict low-carbon microalloying system including Nb, V, Ti, and Mo to ensure fine grain and stable performance.

X70 is typically supplied in TMCP condition, providing excellent toughness and weldability.

Common uses include continental natural gas pipelines, subsea ultra-high-pressure systems, offshore oil extraction, difficult terrain pipelines, and major gas trunk lines.