Description
Direct Mill Supply, Certified Traceability — Every S235JRH / S355JRH square hollow section ships with original mill test certificates and full heat-number traceability, sourced directly from certified mills without intermediary markups.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | S235JRH/S355JRH SHS Hollow Section Black Square Pipe |
| Product Type | Square Hollow Section (SHS) / Square Steel Tube |
| Steel Grade | S235JRH, S355JRH, Q235B, ASTM A500, ASTM A53 Gr.B, S275, STK400 |
| Standard | ASTM A500, ASTM A53, EN 10219, EN 10210, GB/T 3091, DIN, BS |
| Section Shape | Square |
| Size Range | 19mm × 19mm – 800mm × 800mm |
| Wall Thickness | 1 – 30 mm |
| Length | 5.8m / 6m / 11.8m / 12m / Random Length |
| Technique | Welded (ERW) / Seamless |
| Surface Treatment | Black Painting / Galvanized / Varnish / Bare |
| Tolerance | ±1% |
| Ends | Plain |
| Application | Construction structures / Building frames / Curtain wall systems / Support tubes / Machinery / Steel fabrication |
| MOQ | 5 Tons |
| Origin | China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Steel Fabricators | Structural frames, heavy equipment bases, welded assemblies |
| Construction Companies | Building columns, curtain wall supports, scaffolding systems |
| Machinery Manufacturers | Equipment frames, load-bearing structures, conveyor supports |
Where Wall-Thickness Tolerance Decides Structural Integrity on S355JRH Square Hollow Section Orders
Actual thickness deviation beyond ±1% tolerance triggers fabrication rework and structural recalculation.
Procurement teams sourcing S355JRH square hollow section for load-bearing frames frequently discover that suppliers quoting attractive per-ton prices deliver material with hidden negative tolerance — walls thinner than specified. This forces fabricators to either reject shipments at the port or absorb the cost of redesigning welded connections. Missing mill test certificates compound the problem: without verified chemical composition and mechanical properties, customs clearance stalls and engineering sign-off becomes impossible. [NEED_CITE: EN 10219 cold-formed hollow section dimensional tolerance requirements]
Matching S355JRH Square Hollow Section to Structural Load Paths
S355JRH square hollow section delivers higher yield strength than S235JRH, making it the preferred choice for building columns, crane booms, and heavy equipment frames where deflection limits are tight. The 19×19mm to 800×800mm size range covers everything from curtain wall mullions to primary structural members. For corrosive environments — coastal construction, chemical plants, outdoor scaffolding — hot-dip galvanized finish extends service life without field painting. We supply both ERW welded and seamless processes: welded for cost efficiency on standard structural work, seamless where internal pressure or critical fatigue loading applies.
Engineering Compliance and Certification Requirements
Structural hollow sections for European markets must comply with EN 10210 (hot-finished) or EN 10219 (cold-formed) standards, with CE marking mandatory for customs clearance. North American projects specify ASTM A500 Grade B or C, requiring mill certificates showing chemical composition within the A500 table limits. [NEED_CITE: steel grade equivalence between EN 10219 and ASTM A500 standards] Wall thickness selection directly affects section modulus and load capacity — a 100×100×5mm SHS carries significantly less moment than a 100×100×6mm section, yet some suppliers ship the thinner material labeled as the heavier gauge. Our S355JRH square hollow section ships with dimensional reports confirming ±1% tolerance compliance, plus original MTC documenting heat number, chemistry, and mechanical test results.
Steel Grade Selection and Manufacturing Process Fundamentals
The S-series designation (S235JRH, S275JRH, S355JRH) follows EN 10025 structural steel grading, where the number indicates minimum yield strength in MPa — S355JRH delivers roughly 50% higher yield than S235JRH, allowing thinner walls for equivalent load capacity. The “JRH” suffix specifies impact testing at 20°C with Charpy V-notch requirements, critical for welded structures in temperate climates. ERW welded square tubes form from coiled strip through continuous rolling and high-frequency welding, offering tight dimensional control and cost efficiency for sizes up to 400×400mm. Seamless square tubes start from round seamless billets, then undergo cold-drawing through square dies — more expensive, but essential for high-pressure applications or where weld-line integrity is a concern. Surface treatment selection depends on environment: black painting for indoor structural work, hot-dip galvanizing for outdoor or corrosive exposure, bare for projects requiring field welding or custom coating.
Hidden Costs of S355JRH Square Hollow Section Procurement Errors
Ordering S355JRH square hollow section with forged or missing mill certificates creates cascading failures: customs holds material at destination port pending chemical verification, fabricators cannot proceed with welding procedures qualified to specific heat numbers, and structural engineers refuse sign-off without traceable test data. [NEED_CITE: consequences of missing mill test certificates in structural steel procurement] Negative tolerance abuse — shipping 4.5mm wall as 5mm specified — reduces section modulus and forces costly field reinforcement or complete member replacement. Grade substitution without notification (supplying Q345B labeled as S355JRH) may pass visual inspection but fails impact testing at specified temperatures, creating latent safety risks in seismic or dynamic loading zones.
Why Procurement Teams Specify Our S355JRH Square Hollow Section
We operate as a dedicated plate and coil division under Shandong Xin Jiyuan Special Steel Tube Co., Ltd, sourcing directly from certified mills — no trading company markups, no unverified material mixing. Every S355JRH square hollow section ships with original mill test certificates showing heat number, chemical composition, and mechanical properties, with full traceability back to the rolling schedule. Our facility maintains ISO 9001:2015 certification and offers SGS/BV third-party inspection before shipment for clients requiring independent verification. Custom cutting to size, leveling, and end preparation available per drawing — we process 5.8m, 6m, 11.8m, and 12m lengths to your exact specifications, eliminating field cutting waste. Professional heavy cargo logistics: we load square tubes with proper edge protection and weight distribution, avoiding the container damage and overweight penalties that plague suppliers unfamiliar with flat product shipping. [NEED_CITE: proper container loading techniques for heavy steel flat products]
Documentation & Compliance
- Mill test certificate documenting S355JRH chemical composition (C, Mn, Si, P, S) and yield strength per EN 10219
- CE certificate confirming EN 10210 / EN 10219 compliance for European market customs clearance
- ISO 9001:2015 quality management system certificate covering square hollow section production and inspection
- SGS or BV third-party inspection report available before shipment for independent dimensional and material verification
- Material traceability by heat number linking each bundle to specific mill test certificate and rolling schedule
- Customs documentation including packing list, bill of lading, and certificate of origin for destination port clearance
Packaging, Loading & Delivery
- S355JRH square hollow section bundled with steel strips and edge protectors to prevent coating damage and bundle deformation during ocean transit
- Galvanized finish square tubes wrapped with waterproof paper and plastic sheeting to preserve zinc coating integrity in humid container environments
- 6m and 12m lengths loaded in 20ft and 40ft containers with weight distribution optimized to avoid overweight penalties and port delays
- Custom cut-to-length square tubes bundled separately with length and heat number labels for site identification and traceability
-唛头 marking each bundle with steel grade (S355JRH), size specification, heat number, and purchase order reference for customs and site receiving
- FOB, CIF, and DDP shipping terms available with professional flatbed and open-top container loading for oversized square hollow sections
Initiating Your S355JRH Square Hollow Section Inquiry
Submit your specification sheet including steel grade (S235JRH or S355JRH), outer dimensions, wall thickness, length requirements, surface treatment preference, and destination port — we respond within 12 hours with detailed quotation including material cost, processing fees, and shipping terms. For custom cut-to-size orders, provide fabrication drawings and we confirm dimensional feasibility before contract execution. Mill test certificates and third-party inspection reports available for review before shipment to verify compliance with your project specifications.
Frequently Asked Questions
Q: What is the grade equivalence between S355JRH, ASTM A500 Gr. C, and Q345B?
A: S355JRH per EN 10219 corresponds roughly to ASTM A500 Grade C in yield strength range, while Chinese Q345B (GB/T 1591) offers similar mechanical properties. However, chemical composition limits and impact testing requirements differ between standards — we provide cross-reference documentation and can supply material tested to multiple standard specifications for projects requiring dual certification.
Q: Can you provide mill test certificates and arrange third-party inspection?
A: Yes, every S355JRH square hollow section shipment includes original mill test certificate documenting heat number, chemical composition, and mechanical properties. SGS or BV third-party inspection is available before shipment for independent verification of dimensions, surface quality, and material compliance.
Q: What is the MOQ for custom cut-to-length square tubes?
A: Standard MOQ is 5 tons for stock sizes. Custom cut-to-length orders follow the same 5-ton minimum, with processing fees calculated based on cutting complexity and quantity. We maintain ready stock across common specifications for faster delivery on urgent requirements.
Q: What surface treatment options are available for indoor vs. outdoor applications?
A: For indoor structural work with controlled environments, black painting or bare finish provides adequate protection. Outdoor applications, coastal construction, or corrosive environments require hot-dip galvanizing for long-term corrosion resistance. Varnish coating offers intermediate protection for projects requiring temporary weather resistance during construction phases.
Q: How do you handle heavy cargo shipping and container loading for long-length square tubes?
A: We load 6m and 12m square hollow sections using professional flatbed and open-top container equipment with proper weight distribution and edge protection. Our logistics team calculates container capacity to avoid overweight penalties and coordinates with shipping lines for break-bulk options when container loading is impractical for oversized sections.
Get Your S355JRH Square Hollow Section Quote with Mill Test Certificate
Send your specification requirements — steel grade, dimensions, wall thickness, length, quantity, and destination port — to receive detailed pricing and original mill test certificate samples within 12 hours.
Company: Shandong Xin Jiyuan Special Steel Tube Co., Ltd
Website: www.xjyplate.com
Tel: +86 531 8573 6315
Mobile/WhatsApp/WeChat: +86 188 5315 7756
Email: admin@xjyplate.com
Address: No.11889, Jingshi West Road, Lulian Group, Jinan City, Shandong Province, China
