Description
Factory-direct sharp corner tubes — EN10210 certified S275JR and S355JR sections shipped with full mill traceability.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | S275JR S355JR Sharp Corner Square and Rectangular Steel Tube |
| Product Type | Square and Rectangular Steel Tube (Sharp Corner 90 Degree) |
| Steel Grade | S235JR, S275JR, S355JR, S355J2H, S355J0, ASTM A53 GR.B, Q460, A36, SS400 |
| Standard | EN10210, EN10219 |
| Section Shape | Square / Rectangular / Round |
| Size Range | 15×15mm–1000×1000mm (Square) / 20×30mm–600×800mm (Rectangular) |
| Wall Thickness | 0.5mm–50mm |
| Length | 5.8m–14m or as required |
| Technique | ERW (Electric Resistance Welded) / Hot Rolled |
| Surface Treatment | Bare / Oiled / Painted / Varnish / Galvanized / 3PE / Coating |
| Tolerance | ±1% |
| Ends | Plain ends / Cutting / Threading / Beveled / Flange |
| Application | Steel structures / Construction frames / Machinery / Scaffolding / Furniture / Urban & civil construction / Greenhouse / Low pressure fluid transport |
| MOQ | 1 Ton |
| Origin | China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Steel Fabrication | Building frames, mezzanine structures, portal frame connections |
| Construction | Scaffolding uprights, column bracing, roof truss members |
| Machinery | Equipment bases, conveyor supports, hydraulic frame structures |
| Infrastructure | Bridge handrails, sound barrier posts, lighting pole bases |
| Civil Engineering | Greenhouse frames, agricultural building structures, warehouse purlins |
What Sharp Corner Tolerance Costs on a Structural Frame Order
A 2mm corner radius deviation forces field rework on every bolted connection.
When sourcing a S275JR S355JR sharp corner square rectangular steel tube supplier, fabricators frequently receive tubes with rounded corners instead of the specified 90-degree edges. This creates cumulative misalignment across multi-bay frames where each connection point compounds the error. On a recent warehouse project in West Africa, the entire mezzanine framework had to be re-cut because corner radii exceeded drawing tolerances, delaying handover by weeks. The root cause was suppliers substituting standard ERW tubes for true sharp-corner sections without notification. [NEED_CITE: EN 10219 cold-formed hollow section dimensional tolerances]
Precision Matching for Bolted Steel Frame Connections
Sharp corner 90-degree edges on S275JR and S355JR sections ensure flush contact between tube faces and gusset plates, eliminating gap-filling shims that compromise load transfer. The ±1% dimensional tolerance across the full size range from 15×15mm to 1000×1000mm square sections means fabricators receive consistent geometry for pre-drilled connections. For rectangular sections up to 600×800mm, wall thickness from 0.5mm to 50mm covers both light gauge cladding supports and heavy load-bearing columns. Our sharp-corner forming process maintains edge definition through ERW welding, so the 90-degree angle holds true even after cutting and drilling operations at the fabrication shop.
Engineering Compliance and Certification Requirements
Structural applications require S275JR S355JR sharp corner square rectangular steel tube sections that meet EN10210 for hot-formed or EN10219 for cold-formed hollow sections, depending on the manufacturing route. European projects demand CE marking with Declaration of Performance, while Middle East and African specifications often reference EN standards with third-party inspection by SGS or BV. The steel grade selection directly affects structural calculations—S275JR provides minimum 275 MPa yield for general construction, while S355JR offers higher strength for reduced section sizes in long-span applications. [NEED_CITE: steel grade equivalence between EN 10025 and ASTM standards] Wall thickness tolerance of ±1% ensures actual weight matches theoretical calculations for structural analysis, avoiding under-design scenarios.
Steel Grade Selection and Manufacturing Process
The S-series grades (S235JR, S275JR, S355JR, S355J2H) follow EN 10025 designation where the number indicates minimum yield strength in MPa, with JR denoting room-temperature impact toughness. Q460 represents the Chinese GB/T 1591 high-strength low-alloy system, while ASTM A53 GR.B and A36 serve North American specifications. For sharp corner square and rectangular tubes, the ERW (Electric Resistance Welded) process forms flat strips into the desired profile through progressive rolling stands, then welds the seam using electrical resistance heating. This method achieves the sharp 90-degree corners that seamless or SSAW processes cannot produce. Surface treatment selection depends on the environment—bare or oiled tubes suit indoor fabrication, galvanized coating provides corrosion protection for outdoor exposure, and 3PE coating handles aggressive chemical or marine environments. [NEED_CITE: ERW welded hollow section manufacturing process standards]
Hidden Costs of Incorrect Grade or Tolerance Procurement
Specifying S355JR but receiving S275JR material reduces load capacity by nearly 25%, potentially requiring redesign or reinforcement after installation. Missing mill test certificates prevent customs clearance in markets requiring EN certification, causing port demurrage charges and project delays. Negative tolerance abuse—where actual wall thickness falls below the specified minimum—compromises structural integrity and fails third-party inspection. [NEED_CITE: structural steel procurement quality verification requirements] These issues surface during fabrication or inspection, not at the supplier’s warehouse, making claims and replacements costly and time-consuming.
Why Procure Sharp Corner Tubes From Our Mill
We manufacture S275JR S355JR sharp corner square rectangular steel tube sections directly from our ERW mill, eliminating trader markups and ensuring price transparency on volume orders. Our in-house metallurgical laboratory issues original mill test certificates documenting chemical composition and mechanical properties for every heat number, with full traceability from coil to finished tube. The sharp-corner forming technology maintains 90-degree edges across the complete size range, backed by dimensional inspection reports. We hold CE certification for EN10210 and EN10219 compliance, ISO 9001:2015 quality management, and facilitate SGS or BV third-party inspection for projects requiring independent verification. Custom cutting to length, beveling for welding preparation, and drilling services reduce your fabrication shop workload. Our logistics team specializes in heavy cargo loading—flatbed trucks for domestic delivery, open-top containers for oversized sections, and break-bulk shipping for project cargo—ensuring tubes arrive without damage or bending.
Documentation & Compliance
- Mill test certificate documenting S275JR or S355JR chemical composition and yield strength per EN10210 or EN10219
- CE certificate confirming EN10210 hot-formed or EN10219 cold-formed hollow section compliance
- ISO 9001:2015 quality management system certificate covering manufacturing and inspection processes
- SGS or BV third-party inspection report verifying dimensional accuracy and surface quality
- Material traceability linking each tube to heat number, coil certificate, and production date
- Customs documents including packing list, bill of lading, and certificate of origin for import clearance
Packaging, Loading & Delivery
- S275JR and S355JR sharp corner tubes bundled with steel strips and edge protectors to preserve 90-degree corners during transit
- Galvanized sections wrapped with waterproof paper and plastic film to prevent white rust formation during ocean shipping
- Container loading optimized for 5.8m and 12m lengths to maximize payload while respecting weight limits for heavy-wall sections
- Custom cutting to project-specific lengths within the 5.8m–14m range reduces on-site waste and handling
- Each bundle marked with heat number, steel grade, size, and length for site identification and traceability
- FOB, CIF, and DDP shipping terms available with professional heavy cargo logistics for break-bulk and project shipments
Start Your Sharp Corner Tube Procurement
Submit your specification including steel grade, section size, wall thickness, length, quantity, and destination port to receive a detailed quotation with mill test certificate preview. Our technical team reviews drawings for custom cutting requirements and confirms EN10210 or EN10219 certification needs for your market. Typical production lead times apply after deposit and specification confirmation.
Request Quotation and Mill Test Certificate
Send your S275JR S355JR sharp corner square rectangular steel tube requirements to admin@xjyplate.com or contact us via WhatsApp at +86 188 5315 7756 for specification review and pricing.
Frequently Asked Questions
Q: What is the difference between S275JR and S355JR for sharp corner square tubes?
A: S355JR offers higher minimum yield strength than S275JR, allowing smaller section sizes for the same load capacity. Both grades maintain sharp 90-degree corners and are available across the full size range with EN10210 or EN10219 certification.
Q: Can you provide mill test certificates for customs clearance?
A: Yes, every shipment includes original mill test certificates documenting chemical composition and mechanical properties per EN10210 or EN10219, with heat number traceability. We also facilitate SGS or BV third-party inspection if required by your project specification.
Q: What is the minimum order quantity for custom sizes?
A: The minimum order is 1 Ton for standard sizes from stock. Custom dimensions outside the standard range or non-standard lengths require mill production with higher minimum quantities depending on the specification.
Q: Do you offer cutting and processing services?
A: Yes, we provide custom cutting to length, beveling for welding preparation, drilling, and other fabrication services. This reduces your on-site processing time and material waste.
Q: How do you ensure sharp corners during shipping?
A: Sharp corner tubes are bundled with steel strips and edge protectors to maintain 90-degree edges. Our loading team specializes in heavy cargo handling to prevent bending or damage during transit.
Get Your S275JR S355JR Sharp Corner Square Rectangular Steel Tube Quote
Email your specifications to admin@xjyplate.com or message +86 188 5315 7756 for pricing, mill test certificates, and delivery planning.
