Square & Rectangular Black Steel Tube

Square & Rectangular Black Steel Tube is a high-quality carbon steel hollow section with a black surface finish, manufactured through advanced welding processes such as ERW (Electric Resistance Welding). It features high strength, excellent weldability, accurate dimensions and reliable structural performance, making it widely used in construction, steel structures, machinery manufacturing and industrial applications. As a professional black steel tube manufacturer and supplier, we provide square and rectangular black steel tubes in various sizes, wall thicknesses and lengths. Our products are available in different steel grades, including Q195, Q235, Q345, ASTM A500, S235JR, S355JR and other equivalent materials. All products are manufactured according to international standards such as ASTM, EN, DIN, JIS, GB, ISO and BS. Black square and rectangular steel tubes are commonly used as structural components due to their excellent load-bearing capacity and stable performance. Compared with galvanized tubes, black steel tubes have a natural mill finish and are suitable for applications where additional painting, coating or surface treatment will be applied after fabrication. Our products are widely used in building structures, steel frames, machinery, agricultural equipment, greenhouse structures, fencing, scaffolding, transportation facilities and general industrial projects. We offer customized solutions with different dimensions, thicknesses, lengths and packaging options according to customer requirements. With strict quality control, advanced production facilities and professional export experience, we supply reliable square and rectangular black steel tube solutions for customers worldwide.