Description
Factory-Direct Galvanized Tube Supply — Hot dip galvanized square steel tubes produced in-house with full CE EN10210/EN10219 certification, shipped directly from our Jinan facility to project sites across 50+ countries.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | Hot Dip Galvanized Square Steel Tube |
| Product Type | Square / Rectangular / Round Steel Tube |
| Steel Grade | 20#, S235, S275, S355JR, A53 Grade B, A500 Grade A/B/C, STK400, SS400, ST42.2 |
| Standard | ASTM A53, ASTM A500, BS1387, EN10255, EN10219, JIS G3444, GB/T3091, GB/T13793 |
| Section Shape | Square / Rectangular / Round |
| Size Range | 21.3 mm – 660 mm (1/2″ – 26″) |
| Length | 5.8 m / 6 m / 11 m or customized |
| Technique | Hot-dip Galvanizing |
| Surface Treatment | Hot Dip Galvanized / Pre-Galvanized |
| Pipe Ends | Plain ends / Beveled ends / Threaded ends / Grooved ends |
| Processing Service | Welding / Punching / Cutting / Bending |
| Tolerance | ±1% |
| Application | Scaffolding / Greenhouse structures / Construction / Fluid transport |
| MOQ | 1 Ton |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Construction & EPC | Building frames, scaffolding systems, structural columns for commercial and industrial projects |
| Agriculture | Greenhouse skeleton structures, irrigation support frames, crop shelter frameworks |
| Steel Fabrication | Welded trusses, base plates, portal frame components for warehouses and workshops |
| Infrastructure | Bridge handrails, highway signpost supports, utility pole foundations |
| Machinery | Equipment frames, conveyor supports, hydraulic system housings |
What Uneven Zinc Coating Costs on a Scaffolding Project
A 35-micron zinc layer on a 65-micron spec means the entire container gets rejected at destination.
On an EPC housing project in West Africa, a batch of hot dip galvanized square steel tubes arrived at port with coating thickness well below the contract requirement. The client’s gauge readings triggered a full return for re-galvanizing — twenty-plus days of delay, demurrage charges, and near-contractual penalties. The root cause was inconsistent bath temperature and withdrawal speed at the galvanizing line, issues that only surface during third-party inspection, not visual checks. [NEED_CITE: hot dip galvanizing coating thickness standards per ISO 1461] When sourcing a Hot Dip Galvanized Square Steel Tube Supplier, coating uniformity documentation is as critical as dimensional accuracy.
Matching Structural Frames and Greenhouse Skeletons to Corrosive Environments
Hot dip galvanized square steel tubes in S235 and S355JR grades provide the corrosion resistance scaffolding and greenhouse structures demand. The zinc metallurgical bond formed during hot-dip immersion — typically 65 microns and above — outperforms pre-galvanized alternatives in humid subtropical and coastal project environments. For greenhouse frames exposed to fertilizer vapors and irrigation moisture, this coating longevity directly determines maintenance cycles. Our production covers side lengths from 21.3 mm to 660 mm, allowing a single Hot Dip Galvanized Square Steel Tube Supplier to furnish both lightweight greenhouse purlins and heavy-duty scaffolding standards from one order.
Engineering Compliance and Certification Requirements
Structural applications demand documentation that satisfies both design codes and customs authorities. Hot dip galvanized square steel tubes conforming to EN10219 require CE marking under the Construction Products Regulation for EU-bound shipments, while ASTM A500 Grade B/C compliance governs North American structural frame orders. [NEED_CITE: EN 10219 cold-formed structural hollow sections certification requirements] Steel grade equivalence between S-series (S235, S275, S355JR) and ASTM designations must be clearly stated on mill test certificates to prevent material rejection during inspection. For scaffolding systems, dimensional tolerance of ±1% ensures coupler compatibility across the full 21.3 mm to 660 mm range. Custom cut lengths at 5.8 m or 6 m reduce on-site waste and welding joints.
Understanding Steel Grades and Hot-Dip Galvanizing Process
The S-series grading system — S235, S275, S355JR — indicates ascending minimum yield strength, where higher grades carry greater structural loads with reduced cross-section weight. For scaffolding and greenhouse frames, S235 offers adequate strength at lower cost, while S355JR serves heavier load-bearing columns. The ASTM A500 system (Grade A/B/C) follows a similar hierarchy for North American spec compliance. Hot-dip galvanizing immerses formed steel tubes in molten zinc at approximately 450°C, creating a metallurgical zinc-iron alloy layer bonded to the substrate — fundamentally different from electro-galvanizing, which deposits a thinner, mechanically bonded coating. [NEED_CITE: difference between hot dip galvanizing and pre-galvanizing coating structure] Wall thickness tolerance of ±1% ensures that theoretical weight calculations match actual delivered weight, preventing cost disputes on tonnage-invoiced orders.
Hidden Costs of Procuring the Wrong Specification
Ordering hot dip galvanized square steel tubes without verified coating thickness invites corrosion failure within months in aggressive environments — far exceeding the initial price saving from an unverified supplier. Missing CE certificates or incorrect EN standard references on mill test documents cause customs holds at EU ports, with demurrage costs accumulating daily. [NEED_CITE: steel pipe import documentation requirements for EU customs] Negative tolerance abuse — where actual wall thickness falls below the stated minimum — compromises structural load capacity and fails third-party inspection, forcing costly replacement. Material traceability gaps mean that when a structural member fails, the entire batch becomes suspect, triggering full project re-inspection.
Why Project Teams Source From Our Facility
Our Jinan production base operates three dedicated tube lines covering over 2,800 specifications, eliminating the need to split orders across multiple suppliers. The in-house physical and chemical laboratory tests every heat for dimensional accuracy, mechanical properties, and zinc coating thickness before release — data recorded on mill test certificates traceable by heat number. We hold 41 invention patents, including China’s original sharp-corner rectangular tube technology, delivering right-angle aesthetics for architectural facade applications where standard rounded-corner tubes fall short. Full CE certification under EN10210 and EN10219, combined with ISO 9001:2015 and Singapore FPC, clears customs across EU, Middle East, and Southeast Asian markets. Third-party inspection by SGS or BV is arranged on request, with reports provided before container sealing. Custom non-standard sizes, cut lengths, and end treatments are available at 1 Ton MOQ, supporting both prototype and bulk procurement.
Documentation & Compliance
- Mill test certificate documenting S235/S355JR chemical composition and mechanical properties per EN10219 or ASTM A500, traceable by heat number
- CE certificate under EN10210/EN10219 for structural hollow sections entering EU member states
- ISO 9001:2015 quality management system certificate covering hot dip galvanized tube production
- SGS or BV third-party inspection report verifying coating thickness, dimensional tolerance, and surface quality before shipment
- Material traceability sheet linking each bundle to its heat number, production date, and galvanizing batch
- Full export documentation set: commercial invoice, packing list, bill of lading, and certificate of origin
Packaging, Loading & Delivery
- Hot dip galvanized square steel tubes bundled with steel strips and edge protectors to preserve the zinc coating during ocean transit and handling
- Plastic end caps fitted on both ends of each tube to prevent moisture ingress and zinc damage at cut surfaces
- Standard seaworthy packaging with woven bag wrapping, suitable for 5.8 m and 6 m lengths optimized for 20ft and 40ft container loading
- Heat number and steel grade stenciled on each bundle for site identification and material traceability verification
- Professional container loading plans designed for African and Southeast Asian road conditions, with anti-shift bracing to prevent transit damage
- FOB, CIF, and DDP shipping terms available from Qingdao port, with full tracking provided until destination arrival
Getting Your Hot Dip Galvanized Tube Quote Started
Submit your required section shape, side length, wall thickness, steel grade, total tonnage, and destination port — our team responds within 12 hours with unit pricing, lead time, and applicable certification documentation. For non-standard dimensions or custom cut lengths, we provide fabrication drawings and container loading plans before production begins.
Request Pricing and Mill Test Certificates Today
Send your specification sheet to receive a detailed quotation with material test documentation and delivery schedule.
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
