Description
Factory-direct galvanized SHS/RHS manufacturer — Hot-dip and pre-galvanized square and rectangular steel tubes produced on 3 dedicated lines covering 2,800+ specifications with wall thicknesses up to 40mm.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | Galvanized Square and Rectangular Steel Tube |
| Product Type | Hot-dip Galvanized / Pre-galvanized (ERW base) Square and Rectangular Hollow Sections |
| Steel Grade | S235, S275, SS400, A53 Grade B, A500 Grade A/B/C, STK400, S355JR |
| Standard | ASTM A53, ASTM A500, ASTM A36, BS1387, EN10255, ISO65, JIS G3444, GB/T3091, GB/T13793 |
| Section Shape | Square / Rectangular (Round also available) |
| Size Range | Outer diameter 21.3mm–660mm (1/2″–26″) for round; square and rectangular sizes customized |
| Wall Thickness | Customized, up to 40mm |
| Length | 5.8m / 6m / 11m or as customer needs |
| Technique | Hot-dip Galvanizing / Pre-galvanized (ERW base) |
| Surface Treatment | Hot-dip Galvanizing |
| Tolerance | ±1% |
| Ends | Plain ends, Beveled ends, Threaded ends, Grooved ends |
| Processing Service | Welding, Punching, Cutting, Bending |
| Application | Construction, Steel structures, Scaffolding, Furniture, Precision machinery parts, Building industry |
| MOQ | 1 Ton |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Construction & Architecture | Glass curtain wall framing, building structural columns, facade support systems |
| Infrastructure | Scaffolding systems, bridge handrails, highway signpost structures |
| Steel Structure Fabrication | Portal frames, truss members, connection nodes for warehouses and workshops |
| Machinery & Equipment | Conveyor frames, machine bases, hydraulic support columns |
| Furniture & Interior | Display rack structures, mezzanine flooring supports, industrial shelving |
Where Galvanized Corner Quality Decides Facade Acceptance
Standard rectangular tubes with rounded corners (R≥2t) fail architectural inspection when sharp profiles are specified.
I have seen entire curtain wall batches rejected at destination because the galvanized rectangular tubes arrived with visibly rounded corners that created uneven joints against glass panels. The zinc coating looked acceptable from a distance, but under close inspection the corner radius disrupted the clean sightlines that architects demand. For facade contractors working to EN 10219 dimensional tolerances, this is not a cosmetic issue — it is a structural fit-up problem that forces on-site rework or complete replacement. Sourcing a Galvanized Square and Rectangular Steel Tube supplier who can deliver true sharp-corner profiles with consistent zinc thickness changes the entire project timeline. [NEED_CITE: EN 10219 cold-formed structural hollow sections dimensional tolerance requirements]
Matching Galvanized Profiles to Structural and Architectural Demands
Galvanized square and rectangular steel tubes in S235, S275, and S355JR grades serve load-bearing frames where corrosion resistance and dimensional accuracy must coexist. The hot-dip galvanizing process coats both external and internal surfaces, protecting hollow sections from internal condensation corrosion that pre-galvanized tubes cannot address. For curtain wall and facade applications, our patented sharp-corner rectangular tube technology eliminates the rounded corner radius typical of standard roll-formed sections, delivering clean 90-degree edges that align precisely with glass panel mounting brackets. This Galvanized Square and Rectangular Steel Tube range covers 2,800+ specifications, meaning non-standard dimensions for architectural features can be produced without the typical mill minimum order barriers.
Engineering Compliance and Certification Requirements
Structural hollow sections used in load-bearing frames must comply with EN 1993 (Eurocode 3) or AISC 360 depending on the project region, and the steel grade designation on the mill test certificate must match the structural calculations. For EU market imports, CE marking per EN 10210 (hot-finished) or EN 10219 (cold-formed) is mandatory for customs clearance — missing or incorrectly referenced EN standards cause shipment holds at port. The Galvanized Square and Rectangular Steel Tube supply chain must provide traceable heat numbers linking each bundle to its chemical composition and mechanical test results. When specifying S355JR for a European project, the equivalence to ASTM A500 Grade C or GB Q345B must be confirmed in the contract to avoid material substitution disputes during third-party inspection. [NEED_CITE: steel grade equivalence between EN 10219 and ASTM A500 standards]
Steel Grade Selection and Galvanizing Process Fundamentals
S235, S275, and S355JR represent incrementally higher minimum yield strengths in the EN system, where S355JR provides approximately 50% higher yield capacity than S235 for the same cross-section — critical when column sizes are constrained by architectural envelopes. SS400 and STK400 from the JIS system serve similar structural roles in Southeast Asian and Japanese-spec projects, while ASTM A500 Grade A/B/C covers the North American market with different toughness and elongation requirements. The hot-dip galvanizing process immerses fabricated tubes in molten zinc at approximately 450°C, creating a metallurgical bond with the steel substrate that produces coating layers harder than the base metal itself. Pre-galvanized tubes, manufactured from already-coated strip before forming, offer thinner zinc layers suitable for indoor or mild environments but lack the internal coating coverage that hot-dip provides for outdoor or marine-exposed structures. The sharp-corner rectangular tube geometry, protected by 41 invention patents, maintains precise 90-degree angles through the galvanizing bath without corner distortion that conventional dies cannot prevent.
Hidden Costs of Incorrect Grade Specification and Coating Failure
Specifying S235 when structural calculations require S355JR means the frame passes visual inspection but fails load testing — forcing complete disassembly and replacement at multiples of the original material cost. Galvanized tubes with insufficient coating thickness or handling scratches during loading develop localized corrosion within months, particularly at cut edges and weld zones where the zinc layer is disrupted. Missing CE certificates or incorrect EN standard references on mill test documents delay customs clearance for weeks, incurring port storage charges that exceed the tube value itself. A Galvanized Square and Rectangular Steel Tube supplier without in-house testing capabilities cannot verify coating adhesion or thickness before shipment, leaving the buyer to discover defects only after the container arrives. [NEED_CITE: hot-dip galvanizing coating thickness requirements for structural steel]
Why Project Procurement Teams Specify Our Galvanized Tubes
Our factory operates 3 production lines dedicated to square and rectangular hollow sections, eliminating trading company markups and enabling direct mill test certificate issuance for every heat number. The in-house physical and chemical laboratory performs dimensional verification, mechanical testing, and coating thickness measurement before any container is sealed — I personally inspect coating thickness and loading plans because I learned early that immersion time and handling during loading determine whether zinc specification is met at destination. With 2,800+ specifications covering wall thicknesses up to 40mm, custom non-standard sizes for architectural features are produced with low MOQ requirements that traditional mills refuse. Our patented sharp-corner rectangular tube technology, recognized through 41 invention patents, fills the market gap for facade contractors who need true right-angle profiles rather than rounded-corner approximations. Full international certifications including ISO 9001:2015, Lloyd’s CE (EN 10210/EN 10219), Singapore FPC, and SGS/BV verification ensure customs clearance across 50+ export destinations. Professional container loading with anti-damage measures prevents the bending and surface scratches that cause galvanized coating rejection at project sites.
Documentation & Compliance
- Mill Test Certificate documenting S235/S275/S355JR chemical composition and mechanical properties per EN 10219 or ASTM A500 as specified
- CE certificate per EN 10210 (hot-finished) or EN 10219 (cold-formed) for EU market customs clearance
- ISO 9001:2015 quality management system certificate covering production and testing processes
- SGS or BV third-party inspection report verifying coating thickness, dimensional tolerance, and surface quality before shipment
- Material traceability by heat number linking each bundle to its production batch and test results
- Complete customs documents including packing list, bill of lading, and certificate of origin for destination clearance
Packaging, Loading & Delivery
- Galvanized tubes bundled with steel strips and edge protectors to preserve the zinc coating during ocean transit and prevent handling scratches
- Hot-dip galvanized surfaces protected by proper separation materials between bundles to avoid coating adhesion damage during loading
- Container loading optimized for 5.8m, 6m, and 11m lengths with weight distribution calculated to prevent tube deformation during shipping
- Custom cutting to project-specific lengths available before galvanizing to ensure coated ends and eliminate on-site cutting exposure
- Heat number and steel grade markings stenciled on each bundle for site identification and traceability verification
- FOB, CIF, and DDP shipping terms available with professional export documentation and tracking until destination arrival
Starting Your Galvanized Tube Procurement
Submit your specification requirements including section dimensions, steel grade, galvanizing type (hot-dip or pre-galvanized), quantity, and destination port to receive a detailed quotation with unit pricing, production lead time, and applicable mill test certificates. Non-standard sizes and sharp-corner rectangular profiles are quoted separately with custom tooling requirements confirmed before production begins. Certification requirements for your destination market are verified during the inquiry stage to ensure CE, ASTM, or JIS documentation aligns with project specifications.
Frequently Asked Questions
Q: What is the difference between hot-dip galvanized and pre-galvanized square and rectangular tubes?
A: Hot-dip galvanizing immerses finished tubes in molten zinc, coating both external and internal surfaces with a metallurgical bond suitable for outdoor and marine environments. Pre-galvanized tubes are formed from already-coated steel strip, offering thinner zinc layers with limited internal coverage, appropriate for indoor or mild corrosion conditions.
Q: Can you produce sharp-corner rectangular tubes for architectural facade applications?
A: Yes, our patented sharp-corner rectangular tube technology produces true 90-degree corners without the rounded radius typical of standard roll-formed sections. This technology holds 41 invention patents and is specifically developed for glass curtain wall framing and architectural facade systems requiring clean sightlines.
Q: Which steel grade should I specify for a European structural project?
A: For EU projects, S235JR, S275JR, or S355JR per EN 10219 (cold-formed) or EN 10210 (hot-finished) are standard specifications. The grade selection depends on structural load calculations, with S355JR providing higher yield strength for load-bearing frames where cross-section sizes are constrained.
Q: What certifications are required for importing galvanized tubes into the EU?
A: CE marking per EN 10210 or EN 10219 is mandatory for structural hollow sections entering the EU market. Mill test certificates must reference the correct EN standard, and third-party inspection reports from SGS or BV are recommended for project verification.
Q: What is the minimum order quantity for custom non-standard sizes?
A: Custom non-standard sizes are available with low MOQ requirements starting from 1 Ton. Specific tooling and production requirements for non-standard dimensions are confirmed during the quotation stage before production begins.
Request Your Galvanized Tube Quotation with Mill Test Certificates
Send your section dimensions, steel grade, galvanizing type, quantity, and destination port to receive pricing and certification documentation within 12 hours.
Shandong Xin Jiyuan Special Steel Tube Co., Ltd
Website: www.sdxjypipe.com
Tel: +86 531 8573 6315
Mobile/WhatsApp/WeChat: +86 188 5315 7756
Email: admin@sdxjypipe.com
Address: No.11889, Jingshi West Road, Lulian Group, Jinan City, Shandong Province, China
