Square steel is a steel material with a square cross-section, which is mainly divided into two types: hot-rolled square steel and cold-drawn square steel. Hot-rolled square steel is processed through the hot rolling process, and the side length is generally 5 to 250 mm; cold-drawn square steel is processed through the cold drawing process, and the side length is generally 3 to 100 mm. Square steel has high strength, high wear resistance and excellent mechanical properties, and is widely used in construction, machinery, ships, bridges and other fields.