Description
Factory-Direct ASTM A500 Gr.B Supply — Three production lines running simultaneously with 20,000+ tons monthly capacity, eliminating middlemen margins on every ASTM A500 Gr.B square steel tube order.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | ASTM A500 Gr.B Square Steel Tube |
| Product Type | Square and Rectangular Steel Tube / Structural Hollow Section |
| Steel Grade | Q195, Q215, Q235, Q345, #20, #45, S195, S235JR, S355JR, A53 Grade A, A53 Grade B, A500 Grade A, A500 Grade B, A500 Grade C, STK400, SS400, ST42.2 |
| Standard | ASTM A500, ASTM A36, ASTM A53, EN 10219, EN 10210, GB/T 6728, JIS G3466 |
| Section Shape | Square, Rectangular, Round |
| Size Range | Square: 20×20mm–500×500mm; Rectangular: 20×40mm–300×500mm |
| Wall Thickness | 0.5–30mm |
| Length | 3m–12m (random or cut to size) |
| Technique | Hot Rolled / ERW Welded |
| Surface Treatment | Black (oiled/non-oiled), Pre-galvanized (40–80g/m²), Hot-dip galvanized (200–600g/m²) |
| Tolerance | ±1% |
| Ends | Plain / Beveled (customizable) |
| Processing Service | Bending, Welding, Decoiling, Punching, Cutting |
| Application | Steel structures, construction frames, solar structures, fencing, greenhouse frames, machinery, shipbuilding, highway railings, bridges |
| MOQ | 1 Ton |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Construction & Building | Load-bearing column systems, modular building skeletons, portal frame structures |
| Solar & Renewable Energy | Mounting structures and support frames for utility-scale solar farms |
| Infrastructure & Industrial | Highway guardrail posts, greenhouse structural frames, fencing systems, machinery base frames |
| Shipbuilding & Power Engineering | Structural bracing members, cable support frames, platform handrails |
What Negative Wall Tolerance Does to a Structural Frame Budget
A 12% negative tolerance on a 75×75 square tube turns a compliant ASTM A500 Gr.B order into a rejected shipment at the port.
I watched a Saudi infrastructure project reject an entire container of square tubes because the wall thickness drifted past acceptable limits. The SGS report landed on the desk, not the steel. For buyers sourcing an ASTM A500 Gr.B square steel tube from China, the real risk is not the unit price — it is receiving material that fails dimensional checks on arrival, triggering re-order delays and project schedule penalties. Fragmented sourcing across multiple suppliers for different sizes compounds this: each factory applies its own tolerance habits, and no single party owns the full compliance picture. [NEED_CITE: ASTM A500 dimensional tolerance requirements for structural hollow sections]
Matching ASTM A500 Gr.B to Structural Load Paths and Corrosive Environments
An ASTM A500 Gr.B square steel tube in Q235 or S235JR grade covers the yield strength range demanded by most building frames and solar mounting structures — sufficient for gravity-loaded columns and bracing members without over-specifying. When the structure sits in a coastal or industrial atmosphere, switching from black oiled finish to hot-dip galvanized (200–600g/m²) extends service life without changing the structural design. The 20×20mm to 500×500mm size range means a single supplier can furnish everything from purlin sections to main column members, reducing the coordination burden on the procurement team.
Engineering Compliance and Certification Requirements
Structural hollow sections destined for EU markets must conform to EN 10219 (cold-formed) or EN 10210 (hot-formed) with CE marking and FPC certification — missing these documents blocks customs clearance regardless of material quality. For North American projects, ASTM A500 Gr.B is the governing specification, and the mill test certificate must document chemical composition and mechanical properties traceable to heat numbers. Engineers specifying these tubes typically require compliance with load-bearing standards such as EN 1993 or AISC, and the supplier must provide third-party inspection reports from SGS or BV to verify dimensional accuracy and coating thickness before shipment. [NEED_CITE: CE marking requirements for structural steel under EN 10210 and EN 10219]
Steel Grade Equivalence and Manufacturing Process
The ASTM A500 Gr.B square steel tube sits within a broader grade matrix that includes Q195–Q345 (Chinese GB system), S235JR–S355JR (European EN system), and A500 Grade A/B/C (American ASTM system). These grades are not identical but have recognized equivalence mappings — for example, Q235 roughly corresponds to S235JR in yield behavior, while A500 Gr.B demands tighter control on carbon content for weldability. The ERW welded process dominates this size range because it offers consistent seam quality at lower cost than seamless, while hot-rolled sections provide superior corner radii for heavy-load applications. Surface treatment selection follows environment: black oiled for indoor or temporary structures, pre-galvanized (40–80g/m²) for mild outdoor exposure, and hot-dip galvanized (200–600g/m²) for long-term corrosion protection in aggressive atmospheres. Wall thickness tolerance of ±1% ensures the theoretical weight calculation matches actual delivered weight — a detail that matters when freight cost is calculated per ton. [NEED_CITE: steel grade equivalence mapping between ASTM A500, EN 10219, and GB/T 6728]
The Hidden Cost of Unverified Material
Ordering an ASTM A500 Gr.B square steel tube without verified mill test certificates creates downstream risk: the material may arrive with incorrect chemistry, failing weld procedure qualification tests on site. Missing CE or EN certification triggers customs holds that delay project timelines by weeks. Negative tolerance beyond specification limits reduces actual load-bearing capacity, forcing engineers to over-design or reject the shipment entirely. The cost of re-ordering, re-shipping, and project delay typically exceeds the price premium of sourcing from a supplier who provides original MTCs and welcomes third-party inspection. [NEED_CITE: consequences of non-compliant structural steel in construction projects]
Why Buyers Return for Repeat Orders
Factory-direct pricing means no trading company margin sits between the mill and the buyer — volume discounts apply directly to the order. Every batch ships with original mill test certificates showing heat number traceability, and SGS or BV third-party inspection is available before loading to verify dimensions, coating thickness, and mechanical properties. The facility holds ISO 9001:2015, Lloyd’s CE (EN 10210/EN 10219), and FPC certifications, ensuring EU and international customs compliance. With 2,800+ specifications in stock and three production lines running simultaneously, urgent orders and split shipments across multiple sizes can be consolidated into single containers. Non-standard sizes and custom lengths are available with flexible MOQ starting from 1 ton, and the professional export team handles documentation, customs clearance, and container loading optimization to minimize freight cost per ton.
Documentation & Compliance
- Mill test certificate documenting A500 Gr.B chemical composition and mechanical properties per ASTM A500, traceable to heat number
- CE certificate covering EN 10210 and EN 10219 for structural hollow sections destined for European Union markets
- ISO 9001:2015 quality management certificate covering the full production and inspection process
- SGS or BV third-party inspection report verifying dimensional accuracy, coating thickness, and surface quality before loading
- Material traceability documentation linking each bundle to its heat number and production batch
- Complete customs document package including packing list, bill of lading, and certificate of origin
Packaging, Loading & Delivery
- ERW welded square tubes bundled with steel strips and edge protectors to preserve surface finish during ocean transit
- Hot-dip galvanized ASTM A500 Gr.B tubes packed with separation materials to prevent zinc coating damage from friction
- Container loading optimized for 20ft and 40ft units, nesting square tubes by size range to maximize weight utilization and minimize freight cost per ton
- Cut-to-length service available for 3m–12m random lengths, with custom sizing to reduce on-site cutting waste
- Each bundle marked with heat number, steel grade, size, and length for on-site identification and traceability
- FOB, CIF, and DDP terms available with professional export documentation and real-time shipment tracking
Securing Your ASTM A500 Gr.B Order
Submit your specification sheet — including size, wall thickness, steel grade, surface treatment, quantity, and destination port — to receive a factory-direct quotation with volume pricing, delivery timeline, and mill test certificate confirmation. Non-standard sizes and custom lengths are available for review, and third-party inspection arrangements can be confirmed before production begins.
Request Your ASTM A500 Gr.B Square Steel Tube Quotation
Send your specifications via email at admin@sdxinjiyuan.com or contact us on WhatsApp at +86 188 5315 7756 to receive pricing, mill test certificates, and container loading plans within 12 hours.
Frequently Asked Questions
Q: How does ASTM A500 Gr.B compare to EN 10219 and GB/T 6728 for my market?
A: ASTM A500 Gr.B is the governing specification for North American structural projects, while EN 10219 applies to cold-formed hollow sections in European markets and GB/T 6728 covers Chinese domestic standards. The steel grades have recognized equivalence mappings — for example, A500 Gr.B chemistry aligns closely with Q235 and S235JR in yield behavior — and we provide full grade cross-reference documentation to support customs clearance and engineer approval.
Q: Can I verify material authenticity before shipment?
A: Every shipment includes original mill test certificates documenting chemical composition and mechanical properties, traceable to heat numbers. Third-party inspection from SGS or BV is available before loading to verify dimensional accuracy, coating thickness, and surface quality, and the inspection report is included in the documentation package.
Q: What is the minimum order quantity, and can I split shipments across multiple specifications?
A: The minimum order quantity is 1 ton, and we support split shipments across multiple sizes, wall thicknesses, and surface treatments consolidated into single containers. This allows buyers to trial orders or fulfill multi-spec project requirements without committing to full-container quantities of a single size.
Q: How do I choose between pre-galvanized and hot-dip galvanized finish?
A: Pre-galvanized coating (40–80g/m²) suits indoor applications or mild outdoor exposure where budget is a priority, while hot-dip galvanized coating (200–600g/m²) provides long-term corrosion protection for coastal, industrial, or buried applications. The choice depends on the service environment and design life of the structure.
Q: How are containers loaded to minimize freight cost?
A: Container loading plans are optimized by nesting square and rectangular tubes by size range, maximizing weight utilization within 20ft and 40ft units. The export team prepares detailed loading diagrams before shipment to ensure efficient packing and accurate freight cost calculation per ton.
Get Factory-Direct Pricing on ASTM A500 Gr.B Square Steel Tube
Email your specifications to admin@sdxinjiyuan.com or message +86 188 5315 7756 on WhatsApp to receive a detailed quotation with mill test certificates and container loading plans within 12 hours.
