Carbon steel rectangular tube is a welded hollow structural section produced from carbon steel containing manganese, silicon, phosphorus and sulfur. It offers a straightforward manufacturing process, low production cost and broad industrial usability across construction, engineering and machinery sectors. The tubes are commonly specified for building frames, mechanical fabrication, highway infrastructure, bridge construction and pipeline support systems where rigidity and predictable dimensions are required. Standard surface finishes include bright, polished and black, and the product can be combined with value-added services such as CNC machining, centerless grinding, heat treatment, annealing, pickling, polishing, welding and custom cutting or bending.
Technical specifications
| Standard | EN/DIN/JIS/ASTM/BS/ASME/AISI |
| Diameter (mm) | 15x15 mm - 400x600 mm (rectangular/square) |
| Wall thickness (mm) | 1.65-65 mm (welded) |
| Steel grade | Carbon steel |
| Length (m) | 3-12 m (customizable) |
| Coating | Bright, polished or black |