What are the production technical requirements of L290 pipeline steel pipe

L290 pipeline steel is a low-carbon micro-alloyed steel, which is a high-tech content and high value-added product. Pipeline steel production has applied almost all new technological achievements in the field of metallurgy for more than 20 years. The development trend of pipeline engineering is large diameter, high pressure and rich gas transportation, high cold and corrosive service environment, and thickening of submarine pipelines. Therefore, modern pipeline steel should have high strength, high toughness and resistance to brittle fracture, low welding carbon content and good weldability, as well as resistance to HIC and H2S corrosion.

There is no toughness index for pipeline steel in China's external pipeline specifications, only specific requirements for pipe materials:
(1) DWTT≥85% SA at the lowest service temperature (-5 ℃);
(2) Charpy impact absorption work at minimum operating temperature (-5 ° C) ≥145J.

The technical conditions of pipeline steel generally adopt the American Petroleum Institute standard API Spec 5L, but the technical conditions for ordering specific projects or specific users in China are often much stricter than API standards.

The smelting process technology of L290 pipeline steel has more stringent requirements, and the technical difficulties are mainly concentrated on:
1) Control of impurity element content;
2) Inclusion control;
3) Narrow component control