Description
Factory-Direct ERW Tubes — 2,800+ specifications produced on 3 dedicated lines with wall thickness up to 50mm, eliminating middleman markups on every S355JR square steel tube order.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | S355JR Square Steel Tube |
| Product Type | Square / Rectangular Steel Tube (ERW) |
| Steel Grade | S235JR, S275JR, S355JR, S355J0, S355J2H, ASTM A53 GR.B, Q460, A36, SS400 |
| Standard | EN10210, EN10219, ASTM A53, ASTM A500 |
| 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 as per order |
| Technique | ERW (Electric Resistance Welded) / Hot Rolled |
| Surface Treatment | Bare / Oiled / Painted / Galvanized / 3PE / Varnish |
| Ends | Plain / Cut / Threaded / Beveled / Flanged |
| Tolerance | ±1% |
| Application | Urban and civil construction, steel structures, machinery, scaffolding, furniture, greenhouse, low-pressure fluid transport, building materials |
| MOQ | 1 Ton |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| EPC Contractors | Steel structure frames for industrial plants and warehouse projects |
| Construction Companies | High-rise building columns, bridge support members, infrastructure scaffolding |
| Machinery Manufacturers | Precision structural tubes for conveyor systems and equipment fabrication |
| System Integrators | Automation frames, modular support structures for industrial installations |
Where EN10219 Certification Decides Customs Clearance at EU Ports
S355JR square steel tube shipments without proper EN10219 documentation face rejection or re-inspection delays at European customs.
Global buyers frequently encounter three compounding problems: material traceability gaps where heat numbers do not match mill certificates, specification mismatches between ordered and delivered wall thickness, and fragmented sourcing that forces coordination across multiple suppliers for tubes, plates, and beams. When a 40HQ container of S355JR square steel tube arrives at Rotterdam without CE marking or EN10219 compliance paperwork, the entire shipment sits in bonded storage while the importer scrambles for retroactive documentation — costing weeks of project delay and thousands in demurrage. [NEED_CITE: EN 10219 cold-formed welded structural hollow sections compliance requirements]
Matching Structural Load Paths in Steel Frame Construction
S355JR square steel tube in the 100×100mm to 400×400mm range with wall thickness from 5mm to 20mm serves as primary load-bearing members in portal frame structures. The ERW process produces a continuous longitudinal weld seam that maintains uniform strength along the full tube length, critical when these tubes function as columns transferring roof loads to foundation points. Our proprietary sharp-corner rectangular tube technology ensures 90° internal corner radius consistency, allowing flush contact with gusset plates and connection brackets without gap-filling shims — a detail that matters when a Southeast Asia warehouse project requires 600 tonnes of mixed square and rectangular sections to arrive with matching dimensional tolerances.
Engineering Compliance and Surface Protection Selection
Structural steel frames designed under EN 1993 require hollow sections that conform to EN 10219 dimensional and tolerancing standards, with mill test certificates documenting chemical composition and mechanical properties for every heat number. [NEED_CITE: EN 1993 steel structure design code hollow section requirements] For outdoor scaffolding and greenhouse structures exposed to moisture, hot-dip galvanized S355JR square steel tube provides corrosion resistance extending service life beyond bare or oiled alternatives. When project specifications call for ASTM A500 Grade B or C, our mill produces equivalent S355JR tubes with cross-referenced chemistry satisfying both EN and ASTM frameworks, eliminating the need for separate sourcing streams.
Steel Grade Selection and ERW Process Fundamentals
The S-series designation (S235JR, S275JR, S355JR) indicates minimum yield strength in MPa, with S355JR offering approximately 50% higher yield capacity than S235JR for the same cross-section — allowing engineers to specify thinner walls and reduce structural weight without sacrificing load capacity. ERW (Electric Resistance Welded) tube production forms flat steel strip into square or rectangular cross-sections and fuses the seam through electrical resistance heating, producing a weld zone with properties matching the parent metal when properly controlled. Our in-house physical and chemical laboratory tests every production batch for tensile strength, elongation, and chemical composition before release, ensuring S355JR square steel tube meets EN10219 requirements for structural applications. [NEED_CITE: steel grade equivalence between EN 10219 and ASTM A500 standards]
Hidden Costs of Specification Gaps and Certification Failures
Ordering S355JR square steel tube from suppliers lacking in-house testing capability introduces risk: wall thickness may drift below nominal due to uncontrolled rolling tolerance, chemical composition may fall outside EN10219 limits without detection, and missing mill test certificates force costly third-party re-inspection at destination. A single container of non-conforming tubes rejected at project site generates return freight, replacement production lead time, and schedule delays that dwarf the original price difference between qualified and unqualified suppliers. [NEED_CITE: structural steel quality verification and mill test certificate requirements]
Why Project Procurement Teams Source S355JR Square Steel Tube from Our Mill
We operate three dedicated ERW production lines covering 2,800+ specifications from 15×15mm to 1000×1000mm square section and wall thickness up to 50mm, all produced under ISO 9001:2015 quality management with real-time monitoring from our in-house laboratory. Our proprietary sharp-corner rectangular tube technology — holding 41 invention patents — fills specification gaps that standard catalogs cannot cover, allowing custom non-standard sizes with typical production lead times rather than extended waits. Every S355JR square steel tube order ships with original mill test certificates documenting heat number, chemical composition, and mechanical test results, plus CE certification under EN10210/EN10219 for EU market compliance and SGS/BV third-party inspection available upon request. We export to 50+ countries with professional loading plans optimized for container weight distribution and bracing, preventing the transit damage that bends tubes and crushes sharp corners during ocean freight.
Documentation & Compliance
- Mill test certificate documenting S355JR chemical composition (C, Mn, Si, P, S content) and yield strength per EN10219
- CE certificate confirming EN10210/EN10219 compliance for structural hollow sections entering EU customs
- ISO 9001:2015 quality management system certificate covering full production and inspection process
- SGS or BV third-party inspection report verifying dimensional tolerance and surface quality before shipment
- Material traceability documentation linking each tube bundle to specific heat number and production batch
- Customs documentation package including packing list, bill of lading, and certificate of origin
Packaging, Loading & Delivery
- S355JR square steel tube bundled with steel strips and edge protectors to prevent surface damage during handling and transit
- Bare or oiled tubes wrapped in waterproof paper; galvanized tubes packed with spacers to preserve zinc coating integrity
- Container loading plans optimized for 5.8m and 12m lengths, with timber bracing between layers preventing shift and corner crush during ocean freight
- Custom cutting to project-specified lengths within 5.8m–14m range, with cut ends deburred and marked with heat number and steel grade
- Clear bundle identification tags showing steel grade S355JR, section size, wall thickness, heat number, and piece count
- Shipping terms FOB/CIF/DDP available with door-to-door logistics coordination to 50+ countries
Getting Your S355JR Square Steel Tube Quote Started
Submit your specification sheet including section size, wall thickness, total tonnage, steel grade requirement, and destination port — we respond within 12 hours with unit pricing, production timeline, and applicable certification documentation. For non-standard sizes outside catalog range, our engineering team provides custom manufacturing feasibility assessment and lead time confirmation before order placement.
Request S355JR Square Steel Tube Pricing and Mill Test Certificate
Send your specifications via email or WhatsApp to receive detailed quotation with material certification documentation.
Shandong Xin Jiyuan Special Steel Tube Co., Ltd
Website: www.sdxjysteel.com
Mobile/WhatsApp/WeChat: +86 188 5315 7756
Email: admin@sdxjysteel.com
