Description
Factory-Direct Pricing, No Middlemen Markup — every S355JR ERW square steel tube ships directly from our Jinan production lines, cutting trading company margins for volume buyers ordering 80×40×2 mm sections.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | S355JR ERW Square Steel Tube |
| Product Type | Welded Square Steel Tube (ERW) |
| Steel Grade | S235JR, S355, A36, SS400, Q235B |
| Standard | EN 10219, ASTM A500, JIS G3466, GB/T 6728 |
| Section Shape | Square |
| Side Length | 80×40 mm (customizable) |
| Wall Thickness | 2 mm |
| Length | Customized |
| Technique | ERW (Electric Resistance Welding) |
| Surface Treatment | Cold Rolled |
| Tolerance | ±1% |
| Finish | Non-oiled |
| Invoicing | By Theoretical Weight |
| Processing Service | Welding, Punching, Cutting, Bending, Decoiling |
| MOQ | Flexible, from 1 ton |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Commercial Construction | Building trusses, column frames, stadium roof structures |
| Machinery Manufacturing | Conveyor support frames, automation equipment bases, machine guards |
| Infrastructure | Bridge auxiliary structures, greenhouse framing, sound barrier posts |
| Vehicle & Transport | Trailer chassis members, RV structural frames, truck body supports |
| Architectural & Decor | Handrail systems, furniture frames, canopy supports |
Where EN 10219 Certification Decides Customs Clearance for Your S355JR ERW Square Steel Tube
A missing or mismatched CE certificate under EN 10219 can halt an entire container at EU ports.
Global procurement teams routinely face quality uncertainty when sourcing welded hollow sections from overseas suppliers. Mill certificates look pristine on paper, yet independent lab tests reveal chemical composition deviations that compromise weldability and structural performance. Specification gaps compound the problem — standard catalogs rarely cover non-standard dimensions like 80×40 mm, and custom orders carry prohibitive lead times. Fragmented sourcing across multiple suppliers for pipes, sections, and fabrication adds coordination costs and delivery risk. [NEED_CITE: EN 10219 cold-formed welded structural hollow section compliance requirements for EU market entry]
How 80×40 mm ERW Sections Match Structural Framing Demands
The 80×40 mm rectangular profile delivers a favorable strength-to-weight ratio for secondary structural members where torsional rigidity matters more than pure axial load capacity. Cold rolled surface finish arrives non-oiled and fabrication-ready, eliminating degreasing steps before welding or powder coating. Our ERW process produces a consistent weld seam that meets EN 10219 dimensional tolerances, ensuring that 80×40×2 mm S355JR ERW square steel tube sections seat flush against gusset plates and connection brackets without forced fit-up.
Engineering Compliance and Grade Selection for Load-Bearing Frames
Structural engineers specifying EN 10219 hollow sections must verify that the declared steel grade satisfies both the project’s load calculations and the governing design code — whether Eurocode 3, AISC 360, or local equivalents. S355JR provides higher yield capacity than S235JR for the same cross-section, reducing member weight in long-span applications. For projects targeting North American markets, ASTM A500 Grade B equivalence must be documented. Third-party inspection by SGS or BV validates chemical composition and mechanical properties before shipment, preventing costly rejection at the destination port. [NEED_CITE: steel grade equivalence mapping between EN 10219 and ASTM A500 standards]
Understanding ERW Welding and Cold Rolled Finish in Square Tube Production
ERW (Electric Resistance Welding) forms the tube by rolling steel strip into a square profile and fusing the seam through resistive heating — no filler metal required. This process suits high-volume production of 80×40×2 mm sections with tight dimensional control. Cold rolling after forming improves surface finish and achieves the ±1% tolerance specified for this product. The non-oiled finish means the tube arrives clean for immediate welding, punching, or bending without solvent cleaning. S355JR, as a non-alloy structural grade under EN 10219, offers minimum 355 MPa yield strength with good formability, making it suitable for both welded frames and bolted connections. Grade equivalence across standards — S355JR (EN), A36 (ASTM), Q235B (GB), SS400 (JIS) — allows procurement flexibility when projects span multiple regulatory jurisdictions. [NEED_CITE: ERW welded tube manufacturing process and dimensional tolerance standards]
The Hidden Cost of Wrong-Grade Substitution on Structural Projects
Substituting a lower grade without engineering approval — shipping Q235B when S355JR was specified — may pass visual inspection but fails under structural load testing. Customs authorities in the EU and Middle East increasingly require EN 10219 or EN 10210 certificates with traceable heat numbers; containers lacking proper documentation face detention or forced re-export. Negative tolerance abuse — where actual wall thickness falls below the declared 2 mm — reduces load capacity and voids structural calculations. These failures surface during third-party inspection or on-site testing, triggering rework, project delays, and contractual penalties that far exceed the initial price difference. [NEED_CITE: consequences of non-compliant steel grade substitution in structural hollow sections]
Why Volume Buyers Source S355JR ERW Square Steel Tube Directly from Our Jinan Facility
Our three production lines running simultaneously deliver monthly capacity exceeding 20,000 tons, eliminating the lead-time bottlenecks typical of trading companies. Every S355JR ERW square steel tube batch carries original mill test certificates traceable by heat number, with SGS or BV third-party inspection available before container sealing. We maintain ready stock across 2,800+ specifications including standard and non-standard dimensions, supporting urgent project requirements and split shipments. Factory-direct pricing removes intermediary margins, with volume discount programs reviewed every six months for long-term partners. Our export team handles consolidated multi-product container loading — combining square tubes, H-beams, and plates into a single shipment — reducing freight costs per ton. Professional documentation preparation ensures customs clearance compliance across 50+ destination countries.
Documentation & Compliance
- Mill test certificate documenting S355JR chemical composition and mechanical properties per EN 10219, traceable to heat number
- CE certificate confirming compliance with EN 10219 for cold-formed welded structural hollow sections
- ISO 9001:2015 quality management system certificate covering production and inspection processes
- SGS or BV third-party inspection report verifying dimensional tolerance, surface quality, and weld integrity
- Material traceability sheet linking each bundle to its heat number, production date, and test results
- Full customs document package including packing list, bill of lading, and certificate of origin for EU and global ports
Packaging, Loading & Delivery
- Cold rolled S355JR square tubes bundled with steel strips and edge protectors to prevent surface damage during ocean transit
- Non-oiled finish requires moisture-proof wrapping with VCI paper or plastic sheeting to prevent corrosion in humid climates
- 80×40×2 mm sections optimized for container loading with nested stacking arrangements maximizing payload per 20ft or 40ft unit
- Custom length cutting available per project drawings, with each piece marked by heat number and steel grade for site traceability
- FOB, CIF, and DDP shipping terms available with real-time tracking from Jinan inland depot to destination port
- Consolidated loading service combining S355JR ERW square steel tube with other structural sections to reduce per-ton freight cost
Request Your S355JR ERW Square Steel Tube Quotation with Mill Test Certificate
Submit your project specifications — section size, wall thickness, steel grade, total tonnage, and destination port — to receive a competitive factory-direct quotation within 12 hours. Our technical team will confirm dimensional feasibility, provide grade equivalence guidance for your target market, and arrange SGS/BV inspection scheduling. For non-standard dimensions or custom processing requirements including punching, bending, or cutting, we provide detailed fabrication drawings before production begins.
Get Factory-Direct Pricing and Full Mill Documentation
Send your specifications via email or WhatsApp to receive your quotation, mill test certificate sample, and container loading plan.
Email: admin@sdxinjiyuan.com
WhatsApp: +86 188 5315 7756
