Steel is an essential material for national construction and the realization of the four modernizations. It is widely used and has a wide variety. According to the different cross-section shapes, steel is generally divided into profiles, plates, pipes and metal products, and it is divided into heavy rail, light rail, large section steel, medium section steel, small section steel, steel cold-formed section steel. High quality section steel, wire rod, thick steel plate, thin steel plate, electrical silicon steel sheet, strip steel, seamless steel pipe steel, welded steel pipe, metal products and other varieties.