
Carbon steel hollow sections—also known as structural hollow sections (SHS) or tube steel—are versatile structural products widely used in construction, infrastructure, machinery, and industrial applications. Available in square, rectangular, and circular profiles, they offer excellent strength-to-weight ratio, torsional stability, and aesthetic appeal. Huaxia-Steel manufactures and supplies carbon steel hollow sections to international standards with factory-direct pricing and full certification.
Product Overview
Our carbon steel hollow sections are produced from hot-rolled or cold-rolled steel strip using high-frequency induction welding (HFIW) or electric resistance welding (ERW). The welded seam is heat-treated to ensure uniform mechanical properties across the section. Each section is straightened, cut to length, and inspected before packaging.
Key advantages of carbon steel hollow sections include:
- High structural efficiency (strength-to-weight ratio 20–40% better than solid sections)
- Uniform cross-section with consistent mechanical properties
- Excellent weldability and fabrication compatibility
- Smooth surface finish suitable for painting and galvanizing
- Available in square, rectangular, and circular shapes
Specification Table
| Parameter | Square Section | Rectangular Section |
|---|---|---|
| Size Range | 20×20 mm – 400×400 mm | 30×20 mm – 500×300 mm |
| Wall Thickness | 1.0 – 16.0 mm | 1.0 – 16.0 mm |
| Length | 6 m (standard), custom 3–12 m | 6 m (standard), custom 3–12 m |
| Tolerance (Outside) | ±0.5 mm (≤100mm), ±0.8 mm (>100mm) | ±0.5 mm, ±0.8 mm |
| Wall Tolerance | ±10% of nominal thickness | ±10% of nominal thickness |
| Straightness | ≤ 2 mm per meter | ≤ 2 mm per meter |
| Weight (per meter) | 0.59 – 165 kg/m | 0.72 – 187 kg/m |
| Corner Radius | 1.0–2.5× wall thickness | 1.0–2.5× wall thickness |
Common Sizes & Weights (Square Sections)
| Size (mm) | Wall (mm) | Weight (kg/m) | Area (cm²) |
|---|---|---|---|
| 50×50 | 3.0 | 4.25 | 5.41 |
| 50×50 | 4.0 | 5.45 | 6.94 |
| 100×100 | 4.0 | 11.7 | 14.9 |
| 100×100 | 6.0 | 16.9 | 21.5 |
| 200×200 | 6.0 | 35.1 | 44.7 |
| 200×200 | 8.0 | 45.3 | 57.7 |
| 300×300 | 10.0 | 87.6 | 111.5 |
| 400×400 | 12.0 | 138 | 175.8 |
Available Steel Grades
| Grade | Standard | Yield (MPa) | Tensile (MPa) |
|---|---|---|---|
| Q235B | GB/T 6728 | ≥ 235 | 370–500 |
| Q345B | GB/T 6728 | ≥ 345 | 470–630 |
| A500 Gr B | ASTM A500 | ≥ 315 (round), ≥ 317 (shaped) | ≥ 400 |
| A500 Gr C | ASTM A500 | ≥ 345 (round), ≥ 317 (shaped) | ≥ 427 |
| S235JR | EN 10219 | ≥ 235 | 360–510 |
| S355J2H | EN 10219 | ≥ 355 | 470–630 |
Manufacturing Standards

Our hollow sections are produced to the following international standards:
- ASTM A500 — Standard specification for cold-formed welded and seamless carbon steel structural tubing in rounds and shapes (US market)
- EN 10219 — Cold formed welded structural hollow sections of non-alloy and fine grain steels (European market)
- GB/T 6728 — Cold formed steel hollow sections for general structure (Chinese standard)
- JIS G 3466 — Carbon steel square and rectangular tubes for general structure (Japanese market)
- AS/NZS 1163 — Cold-formed structural steel hollow sections (Australian/New Zealand market)
Applications
Carbon steel hollow sections are used across diverse industries:
- Construction: Building columns, beams, roof trusses, scaffolding, and curtain wall support structures
- Infrastructure: Bridge components, highway guardrails, sign posts, and street lighting poles
- Machinery: Equipment frames, conveyor supports, and machine bases
- Automotive: Chassis frames, trailer bodies, and roll cages
- Agriculture: Greenhouse structures, fencing posts, and equipment frames
- Renewable Energy: Solar panel mounting structures and wind turbine towers
Quality Assurance
Every batch of carbon steel hollow sections undergoes rigorous quality control:
- Material certification: EN 10204 3.1 mill test certificate with chemical composition and mechanical properties
- Dimensional inspection: 100% verification of outside dimensions, wall thickness, and length
- Weld seam testing: Ultrasonic testing of weld seam for sizes ≥ 200mm
- Hydrostatic test: Pressure tested to verify weld integrity (optional, on request)
- Straightness check: Measured on a flat surface, deviation ≤ 2mm/meter
- Surface inspection: Visual check for cracks, laps, scars, and weld defects
- Third-party inspection: SGS, BV, or TÜV inspection available upon request
Packaging & Shipping

- Bundled with steel straps (4–6 straps per bundle) for secure transport
- End caps or plastic plugs available to protect against moisture and contamination
- Anti-corrosion options: black painting, galvanizing, or FBE coating
- Container loading: ~20–25 tons per 20ft container, ~25–28 tons per 40ft container
- Custom lengths cut to specification before packaging
- Export documentation: Commercial invoice, packing list, MTC, CO (if required)
Request a Quote
Huaxia-Steel is your trusted factory-direct supplier for carbon steel hollow sections. We offer competitive pricing, reliable delivery, and full certification for all international standards. Contact us today with your size, grade, and quantity requirements for a detailed quotation. Browse our complete carbon steel product range for additional options.





