Description
Factory-direct sharp corner tubes — 41 invention patents covering true 90° right-angle forming for EN10210 S355JR structural hollow sections.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | EN10210 S355JR Sharp Corner Square & Rectangular Steel Tube |
| Product Type | Sharp Corner Square & Rectangular Steel Tube (SHS/RHS) |
| Steel Grade | S235JR, S275JR, S355JR, S355J2H, S355J0H, ASTM A53 GR.B, Q460, A36, SS400 |
| Standard | EN10210, EN10219 |
| Section Shape | Square / Rectangular |
| Size Range | 15×15mm–1000×1000mm (Square) / 20×30mm–600×800mm (Rectangular) |
| Wall Thickness | 0.5mm–50mm |
| Length | 5.8m–14m or custom |
| Technique | Hot Rolled Carbon Steel Welded (ERW) |
| Surface Treatment | Galvanized / 3PE / Painted / Coating Oil / Bare |
| Ends | Plain / Cutting / Threading / Beveled / Flange |
| Tolerance | ±1% |
| Application | Urban/civil construction, machine structure, agriculture equipment, water and gas pipeline, greenhouse, scaffolding, building material, furniture, low pressure fluid transport, oil pipeline |
| MOQ | 1 Ton |
| Origin | China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Façade & Curtain Wall | Glass curtain wall steel framing, architectural facade mullions, right-angle decorative profiles |
| Construction & EPC | High-rise building columns, bridge handrails, infrastructure support frames |
| Steel Structure Fabrication | Welded beam-to-column connections, portal frame members, truss chords |
| Machinery Manufacturing | Conveyor structures, crane booms, equipment base frames |
| Agriculture & Greenhouse | Greenhouse skeleton frames, irrigation support structures |
What Rounded Corners Cost You on a Curtain Wall Project
Standard ERW rectangular tubes produce corners with R≥2t radius — unacceptable for flush-mounted facade brackets.
When rectangular tubes arrive on site with visible corner radii, curtain wall contractors face misaligned mounting plates, uneven gap fills, and re-cutting that delays the entire facade sequence. Specifying an EN10210 S355JR sharp corner square rectangular steel tube with patented 90° forming eliminates this mismatch at the design stage. The problem compounds when multiple batches from different mills show inconsistent corner profiles — some nearly sharp, others visibly rounded — forcing re-inspection of every single piece before welding. [NEED_CITE: cold-formed hollow section dimensional tolerance requirements per EN 10219]
Matching Sharp Corner Geometry to Architectural Steel Framing
The patented sharp-corner forming process produces true 90° edges that sit flush against glass curtain wall mounting brackets, eliminating the gap-filling and re-grinding that rounded-corner tubes demand on site. For an EN10210 S355JR sharp corner square rectangular steel tube used in facade mullions, this means the steel frame aligns precisely with the aluminum or stainless steel connector plates — no shimming, no cosmetic weld repairs visible through the glass. Wall thicknesses from 0.5mm to 50mm cover everything from lightweight decorative infill to heavy structural transfer beams, all within the same ordering cycle.
Structural Compliance and Surface Protection for Field Conditions
Load-bearing facade frames and bridge handrails must satisfy EN 1993 design requirements for hollow section members, which assume consistent corner geometry when calculating section modulus and buckling resistance. [NEED_CITE: EN 1993-1-1 design rules for cold-formed hollow sections] For outdoor or coastal installations, galvanized or 3PE surface treatment extends service life without field repainting, while bare or oiled finishes suit indoor fabrication shops where welding and painting follow delivery. Steel grade selection directly affects load capacity — S355JR provides higher yield strength than S235JR for the same cross-section, reducing member weight in tall building frames. CE certification under EN10210/EN10219 is mandatory for EU customs clearance, and mill test certificates must reference the correct heat number for traceability. [NEED_CITE: CE marking requirements for structural steel hollow sections under EN 10210]
Understanding Steel Grade Selection and ERW Welding for Sharp Corner Tubes
The S-series grades (S235JR, S275JR, S355JR, S355J2H, S355J0H) follow the European EN system where the number indicates minimum yield strength in MPa — S355JR delivers roughly 50% higher yield than S235JR in the same section size, allowing engineers to downsize members and reduce self-weight. The Q-series (Q460) and ASTM grades (A53 GR.B, A36) serve different regional specification systems but can be cross-referenced for international projects. ERW (Electric Resistance Welded) technique joins the formed strip through high-frequency current, producing a consistent longitudinal weld suitable for structural hollow sections up to 50mm wall thickness. The sharp-corner forming process itself requires precise control of the flat-to-bend transition — standard rectangular tube mills produce R≥2t corners because the forming rolls cannot achieve true 90° without cracking the outer fiber, whereas patented tooling manages this deformation through controlled multi-pass bending. Surface treatment choice depends on the service environment: galvanized coating protects against atmospheric corrosion for 20+ years in moderate conditions, 3PE coating suits buried or submerged applications, and painted finishes allow color matching for exposed architectural elements.
Hidden Costs of Specifying the Wrong Corner Profile or Grade
Ordering standard rectangular tubes when the design calls for sharp corners triggers a cascade of field problems: re-cutting corners to fit bracket plates, welding fill material to build up rounded edges, and in worst cases, rejecting entire shipments after the facade contractor discovers the mismatch during dry-fit. Material certification gaps create customs delays — EU importers without proper EN10210/EN10219 CE documentation face border holds and return-to-origin costs. [NEED_CITE: consequences of non-compliant steel certification in EU construction imports] Negative tolerance stacking on wall thickness reduces actual section modulus below design assumptions, potentially requiring structural reassessment and member replacement after delivery.
Why Project Procurement Teams Source Sharp Corner Tubes Here
Every EN10210 S355JR sharp corner square rectangular steel tube rolls through the same patented 90° forming lines that hold 41 invention patents — the same technology that filled the domestic and international gap for true right-angle rectangular hollow sections. An in-house physical and chemical laboratory tests every heat for composition and mechanical properties before release, producing mill test certificates that match the heat number stenciled on each piece. The production lines cover 2,800+ specifications from 15×15mm to 1000×1000mm square and 20×30mm to 600×800mm rectangular, with wall thicknesses reaching 50mm — meaning facade contractors and steel fabricators can consolidate standard and non-standard sizes into one purchase order. Full CE certification under EN10210/EN10219 and ISO 9001:2015 registration clear EU and regulated-market customs, while SGS/BV third-party inspection arrangements provide independent verification before container sealing. Professional container loading with anti-damage measures prevents the bending and surface scratching that plague loosely packed tube shipments.
Documentation & Compliance
- Mill test certificate documenting S355JR chemical composition and mechanical properties per EN10210, referencing the specific heat number for each bundle
- CE certificate confirming EN10210/EN10219 compliance for structural hollow sections, required for EU customs clearance
- ISO 9001:2015 quality management system certificate covering the full production and testing process
- SGS or BV third-party inspection report available upon request, covering dimensional checks, visual inspection, and witness testing
- Material traceability documentation linking each piece to its heat number, steel grade, and production date
- Complete customs document set including packing list, bill of lading, and certificate of origin
Packaging, Loading & Delivery
- Sharp corner tubes bundled with steel strips and edge protectors to preserve the 90° corner geometry and any galvanized or painted surface during ocean transit
- Galvanized EN10210 S355JR sharp corner square rectangular steel tube bundles wrapped with waterproof cloth to prevent white rust formation during container shipping
- Container loading optimized for 5.8m–14m lengths with nested square and rectangular sections to maximize payload per 20ft or 40ft container
- Custom cutting to project-specific lengths available before shipment, reducing on-site waste and cutting labor for facade contractors
- Heat number and steel grade stenciled on each piece for site traceability and inspection verification
- FOB, CIF, and DDP shipping terms available with professional tube loading supervision to prevent shifting and damage
Getting Your Sharp Corner Tube Quote Started
Submit your section dimensions, wall thickness, steel grade (S355JR or equivalent), surface treatment preference, and total tonnage to receive a detailed quotation with unit pricing, production lead time, and shipping terms. Non-standard sizes and custom lengths are available with low MOQ — share your drawing or specification sheet for a technical review. Confirm CE certification requirements and third-party inspection needs upfront so documentation prepares in parallel with production.
Frequently Asked Questions
Q: Can you provide EN10210/EN10219 CE certification for EU market import?
A: Yes, all EN10210 S355JR sharp corner square rectangular steel tubes carry CE certification under EN10210 and EN10219, with full documentation for EU customs clearance. Mill test certificates and CE declarations ship with every order.
Q: What is the MOQ for non-standard sizes outside your regular range?
A: The standard MOQ is 1 Ton. Custom non-standard dimensions and lengths are available — share your specific requirements for a technical feasibility check and quotation.
Q: How do you ensure the sharp corner maintains true 90° angles after forming?
A: The patented sharp-corner forming process uses controlled multi-pass bending tooling that achieves true 90° right angles without cracking the outer fiber. Tolerance is maintained within ±1%, and dimensional inspection occurs before bundling.
Q: Can you arrange SGS or BV third-party inspection before shipment?
A: Yes, third-party inspection through SGS or BV is available on request. The inspection covers dimensional verification, visual surface check, and witness testing, with reports provided before container sealing.
Q: What surface treatment options are available for outdoor facade applications?
A: Galvanized coating provides long-term atmospheric corrosion protection suitable for most outdoor facade and curtain wall applications. 3PE coating and painted finishes are also available for more aggressive environments or specific color requirements.
Q: How do you handle container loading to prevent damage during transit?
A: Professional loading with anti-damage measures includes steel strip bundling, edge protectors for corner preservation, waterproof wrapping for galvanized surfaces, and nested section arrangement to maximize container space while preventing shifting.
Request Your EN10210 S355JR Sharp Corner Tube Quotation
Send your section dimensions, steel grade, surface treatment, and quantity to receive pricing with mill test certificates within 12 hours.
Shandong Xin Jiyuan Special Steel Tube Co., Ltd
Website: www.sdxjypipe.com
Mobile/WhatsApp/WeChat: +86 188 5315 7756
Email: admin@sdxjypipe.com
