Technical Features and Uses of API 5L X42 (L290) Line Pipe Steel

API 5L X42 (L290) is a medium-strength line pipe steel widely used in oil and natural gas transmission projects with higher pressure requirements. With a yield strength of approximately 290 MPa, it provides improved pressure resistance and performance compared to lower grades.

X42 features good mechanical strength, weldability, and toughness, even at low temperatures. These characteristics make it suitable for long-distance pipelines in various climate conditions. It also provides good corrosion resistance when used with proper coating systems.

Its chemical composition belongs to low-alloy steel, generally controlling carbon at ≤0.28% and increasing manganese content to enhance strength. Microalloying additions such as Nb, V, and Ti help refine grains and improve toughness and weldability.

API 5L X42 is supplied in hot-rolled, normalized, controlled-rolled, or TMCP conditions. TMCP significantly enhances toughness and welding performance.

Applications include medium- and high-pressure oil and gas pipelines, petrochemical plant piping, city gas networks, and subsea pipeline systems.