Jiuquan Steel's Q550D high-strength steel has successfully entered the market of leading coal mining machinery manufacturers

Recently, Q550D—a high-strength steel（Prices） developed by Hongxing Hongbo New Materials for use in critical coal mining equipment—has officially been certified as a supplier by a leading domestic manufacturer of comprehensive coal mining equipment, and has begun mass production. This marks Jiuquan Iron & Steel’s successful acquisition of the “golden key” to entering the coal mining machinery industry, securing a significant foothold in the market for high-end steel used in coal mining machinery across Northwest China and the nation as a whole.

Hydraulic supports serve as the “backbone” of comprehensive mechanized mining in coal mines, with high-strength steel accounting for up to 80% of the material used. Jiuquan Iron & Steel’s Q550D/E series of high-strength steels has a yield strength exceeding 600 MPa, and the Grade E products maintain excellent impact toughness at temperatures as low as -40°C, fully meeting the demands of extreme operating conditions. From the project’s initiation in May 2025 to the receipt of the first batch of orders this past February, the product has successfully passed rigorous evaluations of chemical composition, weldability, and mechanical properties. To date, cumulative shipments have exceeded 700 tons, and customer feedback has been excellent.

Leveraging the 10,000-ton rolling mill, ultra-rapid cooling system, and dedicated heat treatment lines on its wide-plate production line, Jiuquan Iron & Steel has mastered two core processes—thermomechanical rolling followed by tempering and quenching followed by tempering—enabling customized production. Currently, process trials for Q690 grades up to 40 mm in thickness have been completed, and R&D for Q890 grades has officially commenced. Jiuquan Iron & Steel is accelerating its expansion into the field of high-strength steel for coal mining machinery.