Description
Direct Mill Supply — Full heat traceability from our own steel production lines to finished galvanized SHS/RHS.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | S235/S355 Galvanized Square Steel Tube |
| Product Type | Galvanized Square and Rectangular Steel Tube (SHS/RHS) |
| Steel Grade | S235, S275, S355, S355J2H, Gr.B, STK400, Q235B, Q345B |
| Standard | ASTM A500, ASTM A53, GB/T 3091, EN 10219, EN 10210 |
| Section Shape | Square / Rectangular |
| Size Range | 19mm × 19mm – 800mm × 800mm |
| Wall Thickness | 1 – 30 mm |
| Length | 5.8m / 6m / 11.8m / 12m / Random Length |
| Technique | ERW (Welded) / Seamless |
| Surface Treatment | Galvanized / Black Painted / Varnish / Bare |
| Tolerance | ±1% |
| Ends | Plain |
| Application | Steel structures / Building frames / Curtain walls / Support tubes / Construction / Machinery / Scaffolding |
| MOQ | 5 Tons |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Commercial Construction | Building frames, column-beam assemblies, mezzanine platforms |
| Industrial Facilities | Warehouse roof trusses, conveyor support structures, equipment platforms |
| Infrastructure & EPC | Bridge railings, sound barrier frames, solar mounting structures |
| Architectural Engineering | Curtain wall support systems, facade structural frames, canopy structures |
| Machinery & Scaffolding | Scaffolding uprights, machinery frames, material handling racks |
Where Negative Tolerance on a Galvanized Square Steel Tube S355 Supplier Order Costs More Than the Steel Itself
Dimensional accuracy on galvanized hollow sections determines whether your structure passes inspection at the port or sits in customs for weeks.
When procurement teams source galvanized SHS/RHS from fragmented supply chains, the steel tube may come from one mill, the galvanizing from another processor, and the documentation from a trading desk with no physical control over either. I watched two full containers of SHS 100×100×4 get held at Santos port because the wall thickness drifted into negative tolerance beyond what the project specification allowed — the third-party inspector flagged every single piece. The replacement material had to go by air. That kind of gap between supplier claims and actual product dimensions doesn’t just delay a project; it rewrites the entire cost structure. [NEED_CITE: EN 10219 dimensional tolerance requirements for cold-formed structural hollow sections]
How Galvanized SHS/RHS Matches Structural Frame and Curtain Wall Demands
Galvanized square and rectangular tubes in S235 through S355 grades cover the load-bearing range that commercial buildings and industrial warehouses demand. The hot-dip zinc coating provides corrosion resistance for exposed structural members — roof purlins, exterior column wraps, and curtain wall support frames that face weather during construction and throughout service life. Sections from 19×19mm up to 800×800mm with wall thicknesses spanning 1–30mm let engineers specify one Galvanized Square Steel Tube S355 supplier for both light-gauge secondary members and heavy primary columns, keeping material certification consistent across the entire frame package.
Engineering Compliance and Certification Requirements for Structural Hollow Sections
Structural frame projects in the European market require CE marking under EN 10210 for hot-finished or EN 10219 for cold-formed hollow sections, with full factory production control documentation. North American projects reference ASTM A500 Grade B or C, while Middle East and Southeast Asian EPC contracts often accept either EN or ASTM frameworks depending on the specifying engineer. The steel grade selection — S235 for non-critical secondary members, S355J2H for low-temperature impact requirements — directly affects connection design and weld procedure qualification. Cut-to-length precision and plain ends prepared for site welding must hold within ±1% tolerance to avoid fit-up delays on the erection floor. [NEED_CITE: steel grade equivalence mapping between EN 10219 and ASTM A500 specifications]
Steel Grade Selection and Galvanizing Process for Hollow Structural Sections
The S-series grades (S235, S275, S355) follow the European EN standard system where the number indicates minimum yield strength in MPa — S355 delivers higher load capacity than S235 for the same cross-section, allowing engineers to reduce member sizes in heavily loaded frames. The Q-series (Q235B, Q345B) maps to Chinese GB standards with similar yield progression, while ASTM A500 Gr.B aligns closely with S275/S355 in mechanical performance. ERW welded production suits the majority of structural applications from 19mm to 800mm outer dimensions, while seamless options serve higher-pressure or more demanding fatigue conditions. Hot-dip galvanizing after fabrication coats both exterior and interior surfaces, providing uniform zinc thickness that protects against corrosion in coastal, industrial, and high-humidity environments — critical for infrastructure projects in Belt & Road markets where maintenance access is limited.
The Hidden Cost of Sourcing from a Galvanized Square Steel Tube S355 Supplier Without Mill Traceability
When material certificates cannot be traced back to a specific heat number from a recognized steel mill, the entire batch becomes unverifiable at the inspection stage. Projects requiring EN 10204 3.2 certificates with third-party witness cannot proceed without documented chemical composition and mechanical test results tied to each production lot. A Galvanized Square Steel Tube S355 supplier who sources black tubes from multiple unknown mills and galvanizes at a separate facility creates documentation gaps that trigger customs holds, project rejections, and in worst cases, structural safety concerns when actual material properties diverge from design assumptions. [NEED_CITE: EN 10204 inspection document types for steel products]
Why Procurement Teams Consolidate Galvanized Hollow Section Orders With Us
Our production model integrates raw steel manufacturing and tube fabrication within the same facility — the same heat of steel that enters our ERW or seamless mill lines carries its chemistry and mechanical test data through galvanizing and into the final mill test certificate. This vertical integration covers over 2,800 specifications across square and rectangular sections, meaning a single purchase order for a warehouse project can include 50×50×3 purlins, 200×200×8 columns, and 400×200×10 rafters all sharing one documentation chain. We hold CE certification for EN 10210 and EN 10219, ISO 9001 quality management, and arrange SGS or BV third-party inspection before shipment for projects requiring independent verification. Custom cut-to-length, non-standard dimensions, and specific coating thickness requests are handled directly by our production engineering team rather than relayed through intermediaries.
Documentation & Compliance
- Mill Test Certificate documenting S355JR chemical composition and yield strength per EN 10219, traceable to individual heat numbers from our own steel mill
- CE certificate confirming compliance with EN 10210 (hot-finished) and EN 10219 (cold-formed) for European market structural projects
- ISO 9001 quality management system certificate covering the full production chain from raw material to galvanized finished tubes
- SGS or BV third-party inspection reports available for pre-shipment verification of dimensions, coating thickness, and surface quality
- Material traceability documentation linking each bundle to its heat number, production date, and test results
- Complete customs documentation package including packing list, bill of lading, and certificate of origin for destination port clearance
Packaging, Loading & Delivery
- Galvanized SHS/RHS bundles secured with steel strips and edge protectors to preserve the zinc coating during ocean transit and handling
- Surface protection maintained through careful stacking separation and moisture barriers for galvanized tubes destined for tropical or coastal project sites
- Container loading optimized for 6m and 12m standard lengths with nested smaller sections to maximize payload per shipment
- Cut-to-length service available for random or specific lengths within the 5.8m–12m range, reducing on-site cutting waste for steel frame projects
- Each bundle marked with heat number, steel grade (S235/S355), section dimensions, and wall thickness for site identification
- FOB, CIF, and DDP shipping terms available with professional oversized cargo loading plans for large-dimension RHS up to 800×800mm
How to Initiate a Galvanized Hollow Section Inquiry for Your Project
Share your project drawings, section schedule, steel grade requirements, and destination port — our engineering team responds within one working day with a detailed quotation covering material, galvanizing, packaging, and freight. We provide shop drawing support, confirm certification requirements for your target market, and lock production scheduling once the order is confirmed.
Request Your Galvanized Square Steel Tube S355 Quotation With Full Mill Documentation
Send your specifications and quantity requirements to receive pricing, lead time confirmation, and sample mill test certificates for your project review.
Company: 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
Address: No.11889, Jingshi West Road, Lulian Group, Jinan City, Shandong Province, China
Frequently Asked Questions
Q: How do S235, S355, and ASTM A500 Gr.B compare for structural hollow section specification?
A: S235 and S355 follow the European EN 10219/EN 10210 standard system where the number indicates minimum yield strength in MPa. ASTM A500 Gr.B is the North American equivalent commonly accepted for similar structural applications. Our mill test certificates document the actual chemical composition and mechanical properties, and we can provide grade equivalence mapping for projects requiring cross-standard compliance.
Q: What galvanized coating thickness standards do your SHS/RHS products meet?
A: Our hot-dip galvanizing process produces uniform zinc coating on both exterior and interior surfaces. Coating thickness is verified with gauge reports included in the quality documentation package. Specific coating requirements can be confirmed during the quotation stage based on your project environment and corrosion protection specifications.
Q: Can you supply non-standard dimensions or custom cut-to-length for galvanized square tubes?
A: Yes. Beyond our standard size range of 19×19mm to 800×800mm with 1–30mm wall thickness, we handle custom cut-to-length requests within the 5.8m–12m range and can discuss non-standard dimension feasibility based on your project drawings. Our integrated production facility allows direct engineering review of custom requirements.
Q: What export documentation do you provide for galvanized SHS/RHS shipments?
A: Each shipment includes Mill Test Certificates with heat number traceability, packing lists, bill of lading, and certificate of origin. CE certificates for EN 10210/EN 10219 compliance are available for European market projects. Third-party inspection reports from SGS or BV can be arranged before shipment upon request.
Q: What is the typical production lead time for galvanized square and rectangular steel tubes?
A: Lead time depends on order quantity, section dimensions, and coating requirements. Standard specifications in S235/S355 grades with hot-dip galvanizing follow typical production scheduling, while custom dimensions or large-volume orders may require adjusted timelines. We confirm specific delivery schedules during the quotation stage.
Get Your Galvanized SHS/RHS Quote With Verified Mill Test Certificates
Submit your project specifications, steel grades, and quantity to receive a detailed quotation with complete documentation and delivery scheduling.
Company: 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
Address: No.11889, Jingshi West Road, Lulian Group, Jinan City, Shandong Province, China
