Description
Direct Mill Supply, No Middlemen — Every S355JR rectangular hollow section steel tube rolls from our own steel mill, backed by full heat-number traceability from slab to finished bundle.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | S355JR Rectangular Hollow Section Steel Tube |
| Product Type | Rectangular Hollow Section (RHS) / Square Steel Tube |
| Steel Grade | Q195, Q235, Q345, S235JR, S275JR, S355JR |
| Standard | ASTM |
| Section Shape | Rectangular |
| Size Range | 0.8 – 15 inches (approx. 20×20mm – 40×80mm) |
| Length | 6m / 6.4m / 12m |
| Technique | Hot Rolled |
| Surface Treatment | Hot Rolled / Black Surface |
| Tolerance | ±1% |
| Ends | Plastic Pipe Cap (End protector) |
| Application | Steel structures / Construction frames / Building frameworks / Ornamental designs / Indoor and outdoor structural use |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Commercial Construction | Building frames, column-beam assemblies, mezzanine platforms |
| Industrial Infrastructure | Factory warehouse structures, conveyor support frames, equipment platforms |
| Architectural Design | Ornamental facades, decorative screen structures, canopy frameworks |
| EPC Projects | Structural bracing, pipe rack supports, modular unit frames |
What Negative Tolerance Really Costs on a Warehouse Frame Order
A ±1% tolerance on hot rolled RHS keeps theoretical weight aligned with structural calculations — but only if the mill actually holds it.
I once watched a site supervisor in Lagos pull a caliper off a 40×80 rectangular tube and find the wall was running so thin that the entire shipment weighed nearly a ton under invoice. The batch got rejected, re-rolled, and shipped again — three weeks of delay on a warehouse frame that was already behind schedule. When you source a S355JR rectangular hollow section steel tube from a trader who buys from multiple mills, you inherit their tolerance lottery. Material certificates look clean on paper, but the actual cross-section tells a different story once it hits the welding jig. [NEED_CITE: impact of wall thickness tolerance on structural steel weight verification]
How Hot Rolled S355JR RHS Matches Structural Frame Demands
Hot rolled rectangular hollow sections in S355JR deliver the yield strength margin that building frames and warehouse structures need under dynamic loading. The black surface from hot rolling provides a stable base for site-applied coatings, and the ±1% dimensional tolerance ensures that connection plates and bolt holes line up without forcing. On EPC infrastructure projects, this S355JR rectangular hollow section steel tube ships with full mill documentation so engineers can verify grade equivalence against EN or ASTM specs before the first weld arc strikes.
Engineering Compliance and Grade Selection for Load-Bearing Frames
Structural frames designed to EN 1993 or AISC standards require hollow sections that carry certified mechanical properties — not just a grade stamp on the bundle tag. S355JR offers higher yield strength than S235JR, which means smaller section sizes can carry the same load, reducing overall steel tonnage and shipping cost. For projects shipping to the EU, EN 10219 compliance documentation is mandatory for customs clearance; for North American EPC jobs, ASTM conformance must be traceable per heat number. Our hot rolled process holds ±1% tolerance across 6m and 12m lengths, which keeps dimensional inspection reports clean and avoids rework at the fabrication shop. [NEED_CITE: EN 10219 hot rolled hollow section dimensional tolerance requirements]
Understanding S355JR Grade and Hot Rolled Process
S355JR sits at the top of the standard S-grade series, offering higher yield strength than S235JR and S275JR — making it the go-to choice for primary load-bearing members in multi-story frames and long-span warehouse structures. The Q-grade equivalents (Q345 mapping to S355JR) follow the Chinese GB system, and specifying the correct grade avoids procurement confusion when drawings mix international standards. Hot rolling produces the black oxide surface that distinguishes this finish from cold-formed alternatives — the process shapes the tube at high temperature, which eliminates residual stress and delivers uniform mechanical properties across the cross-section. Wall thickness tolerance of ±1% matters because even a half-millimeter deviation on a 4mm wall changes the theoretical weight by a measurable percentage over a 12-meter length. When buyers invoice by theoretical weight, tight tolerance protects both sides from disputes at site verification.
Hidden Costs When Tolerance and Certification Fall Short
Ordering a S355JR rectangular hollow section steel tube without verified mill test certificates means you cannot prove grade compliance during structural inspection — which can halt project handover. Tubes that run under nominal wall thickness pass visual checks but fail ultrasonic testing, triggering full-batch rejection and replacement orders that blow the project schedule. Missing CE or ASTM documentation creates customs holds at the destination port, where authorities demand traceable certification before releasing structural steel. The real cost is never the unit price difference — it is the crane rental sitting idle while you sort out which bundle actually meets the drawing spec. [NEED_CITE: structural steel certification requirements for international construction projects]
Why Procurement Teams Source This RHS From Our Mill
We roll the steel, fabricate the components, and ship the finished product — one facility, one quality system, one point of accountability. Our own steel mill produces the S355JR rectangular hollow section steel tube from slab to finished bundle, so every heat number traces back to our ladle analysis. The fabrication workshop next door handles CNC cutting, drilling, and welding if your project needs pre-assembled frames rather than loose tubes. We hold 2,800+ specifications in stock across Q195 through S355JR grades, which means mixed-size container loads ship without waiting for individual mill campaigns. Third-party inspection through SGS or BV runs on your schedule, and our documentation package — MTC, CE certificate, packing list, certificate of origin — clears customs without back-and-forth. Professional loading plans maximize container utilization for 6m and 12m lengths, reducing per-ton freight cost on CIF and DDP shipments.
Documentation & Compliance
- Mill test certificate documenting S355JR chemical composition and mechanical properties per heat number, issued from our own steel mill
- CE certificate confirming EN 10219 compliance for rectangular hollow sections shipped to EU member states
- ISO 9001 quality management certificate covering the full production chain from raw material to finished RHS
- SGS or BV third-party inspection report available upon request, verifying dimensional tolerance and surface quality
- Material traceability linking each bundle to its heat number, with test results traceable to ladle analysis
- Full customs documentation package including packing list, bill of lading, and certificate of origin for destination clearance
Packaging, Loading & Delivery
- Hot rolled black surface RHS bundled with steel strips and edge protectors to prevent surface scratching during ocean transit
- 6m and 12m lengths loaded in dedicated container plans that maximize cubic utilization while keeping bundle weight within port crane limits
- Plastic end caps fitted on every tube end to block moisture ingress and protect the black surface from handling damage
- Heat number and S355JR grade stenciled on each bundle tag, matching the mill test certificate for site verification
- FOB, CIF, and DDP shipping terms available, with door-to-door logistics coordination for EPC project sites
- Custom cutting to non-standard lengths available before bundling, reducing on-site waste for fabrication shops
Start Your S355JR RHS Procurement With Verified Documentation
Send your project drawings or specification sheet — we respond within 24 hours with pricing, mill test certificate samples, and a production timeline. Confirm your required grade, size range, length, and destination port, and we will prepare a container loading plan with full customs documentation.
Request S355JR RHS Quote With Mill Test Certificate
Submit your specifications and destination port to receive pricing, MTC samples, and delivery timeline.
Shandong Xin Jiyuan Special Steel Tube Co., Ltd
Website: www.xjystructure.com
Tel: +86 531 8573 6315
Mobile/WhatsApp/WeChat: +86 188 5315 7756
Email: admin@xjystructure.com
