Description
Factory-Direct Galvanized SHS — 2,800+ specifications in stock for immediate dispatch
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | Q235 / S235 / SS400 Galvanized Square Steel Tube |
| Product Type | Galvanized Square Steel Tube |
| Steel Grade | Q195, Q215, Q235, Q345, S235, SS400 |
| Standard | GB |
| Section Shape | Square / Rectangular / Round |
| Size Range | Wall Thickness 0.5–80 mm |
| Length | 6 m (standard), customizable |
| Technique | ERW |
| Surface Treatment | Galvanized Coated |
| Zn Coating Thickness | 30–650 g/m² |
| Tolerance | ±1% |
| Invoicing | By Theoretical Weight |
| Packing | Customized / Export Standard Packing |
| Alloy | Non-Alloy |
| Application | Construction frames / Scaffolding / Steel structures / Machinery / Bridge / Electrical installation / Mining |
| MOQ | 25 Tons |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Construction & Infrastructure | Scaffolding systems, building frames, structural columns for commercial and residential projects |
| Industrial Engineering | Machinery frames, conveyor support structures, equipment bases |
| Power & Electrical | Electrical installation poles, cable tray supports, substation frameworks |
| Mining | Underground support structures, ventilation shaft frames, equipment platforms |
| Bridge & Civil Works | Bridge railings, pedestrian walkway supports, structural bracing members |
When Zinc Coating Thickness Decides Whether Your Shipment Clears Customs
A 30 g/m² coating and a 650 g/m² coating look identical to a customs inspector — but only the mill test certificate proves which one you actually ordered.
Buyers across West Africa and Southeast Asia routinely face shipment holds because the galvanizing thickness on arrival does not match the purchase order. The galvanizing layer is invisible to the naked eye once the tubes are stacked in a container, and port inspectors rely entirely on documentation. Without an original mill test certificate showing the exact zinc coating weight per square meter, your cargo sits at the port while demurrage charges accumulate. I have seen project timelines slip by weeks because a supplier could not produce traceable test records linking each bundle to its heat number and coating measurement.
[NEED_CITE: hot-dip galvanized coating thickness standards for structural steel tubes]
How ERW Galvanized Square Tubes Perform in Scaffolding and Structural Frames
Galvanized square steel tubes in Q235 and S235 grades carry the load requirements typical of scaffolding systems and building frames across tropical and coastal job sites. The ERW welding process produces a consistent longitudinal seam that maintains dimensional accuracy under the ±1% tolerance, which matters when scaffold couplers must grip evenly on every joint. The galvanized coating at 30–650 g/m² gives project teams flexibility — lighter coatings for indoor or temporary structures, heavier coatings for permanent outdoor frames exposed to humidity and salt air. As a Galvanized Square Steel Tube supplier running three production lines simultaneously, we hold standard sizes in ready stock so that urgent scaffold replenishment orders do not wait for production scheduling.
Structural Compliance and Certification Requirements for Galvanized SHS
Engineering specifications for scaffolding and structural frames typically reference load-bearing standards that demand verifiable material properties. The Q235 grade meets Chinese GB standards, while S235 and SS400 serve as direct equivalents for European and Japanese specification systems respectively — choosing the correct designation avoids rejection at the design review stage [NEED_CITE: steel grade equivalence between GB Q235 EN S235 and JIS SS400]. For projects entering the EU market, our Galvanized Square Steel Tube production carries Lloyd’s CE certification under EN 10210 and EN 10219, ensuring that the hollow sections meet the dimensional and mechanical requirements European inspectors expect. The 6-meter standard length works for most container shipping configurations, while custom cut-to-length orders eliminate on-site cutting waste and reduce secondary processing costs at the project location.
Understanding Steel Grade Selection and Galvanizing Process for Square Tubes
The Q series (Q195 through Q345) follows the Chinese GB standard system where the number indicates minimum yield strength in MPa — Q235 delivers adequate strength for most general construction and scaffolding applications at a competitive cost point. S235 under EN standards and SS400 under JIS serve as functional equivalents, allowing buyers to specify the grade their local engineer approves without changing the actual product. ERW welding forms the square profile from hot-rolled coil through a continuous forming and welding process, producing tight dimensional tolerances suitable for structural connections. The galvanizing step — whether at 30 g/m² for light indoor protection or 650 g/m² for aggressive coastal and industrial environments — adds corrosion resistance without altering the structural geometry. Wall thickness from 0.5 mm to 80 mm covers everything from light gauge electrical conduit frames to heavy-duty structural columns, with theoretical weight invoicing giving transparent and predictable cost calculation.
Hidden Costs When Galvanizing Specifications Go Unverified
Ordering Galvanized Square Steel Tube by price alone without verifying zinc coating thickness creates a cascade of downstream costs. Tubes with coating below the specified g/m² value begin corroding within months in humid environments, leading to premature replacement and structural safety concerns. Missing or incomplete mill test certificates cause customs delays that trigger port storage fees and project schedule penalties. Material traceability gaps mean that when a structural inspector questions a specific batch, the buyer cannot link the tubes back to their original heat number and production record — a situation that can halt an entire project验收 [NEED_CITE: importance of material traceability and mill test certificates in structural steel procurement].
Why Project Buyers Source Galvanized Square Steel Tube From Us
We operate as a direct manufacturer with no trading intermediaries, which means the price you receive reflects actual production cost plus a transparent margin. Our factory maintains a standing inventory covering 2,800+ specifications across square, rectangular, and round profiles, so standard-size Galvanized Square Steel Tube orders ship without waiting for production runs. Every batch leaves our facility with an original mill test certificate documenting chemical composition, mechanical properties, and zinc coating weight — and we welcome SGS or BV third-party inspection at any stage before shipment. Our production lines hold ISO 9001:2015 certification and Lloyd’s CE (EN 10210/10219) with FPC factory production control, covering the documentation requirements for EU, Middle East, and African project compliance. For non-standard dimensions or custom lengths outside the 6-meter default, we offer flexible MOQ starting from trial quantities up to full-container bulk orders with the same factory-direct pricing structure.
Documentation & Compliance
- Mill test certificate documenting Q235/S235/SS400 chemical composition, yield strength, and zinc coating thickness (30–650 g/m²) per GB standard, traceable by heat number
- CE certificate under EN 10210 / EN 10219 for galvanized hollow sections entering European Union markets, issued by Lloyd’s Register
- ISO 9001:2015 quality management system certificate covering the full ERW welding and galvanizing production process
- SGS or BV third-party inspection report available upon request, covering dimensional verification, coating thickness measurement, and visual surface quality
- Material traceability documentation linking each bundle to its heat number, production date, and coating batch for project audit compliance
- Full customs document package including commercial invoice, packing list, bill of lading, and certificate of origin for destination-country clearance
Packaging, Loading & Delivery
- Galvanized square tubes bundled with steel strips and edge protectors to prevent coating damage and zinc flaking during ocean transit and handling
- Surface protection maintained through careful stacking with separation layers, preserving the 30–650 g/m² zinc coating integrity across all Q235, S235, and SS400 grades
- Container loading optimization for 6-meter standard length tubes, maximizing payload per 20ft and 40ft containers with professional lashing and weight distribution
- Custom cut-to-length service available for project-specific dimensions, reducing on-site cutting waste and improving installation efficiency at the construction location
- Heat number and steel grade markings stenciled on each bundle for on-site identification and traceability verification during project inspection
- FOB, CIF, and door-to-door logistics coordination with professional export documentation handling for destinations across 50+ countries
Ready to Lock in Pricing and Mill Test Certificates for Your Next Shipment
Submit your specification sheet — including steel grade (Q235, S235, or SS400), section dimensions, wall thickness, zinc coating requirement, and total quantity — and receive a factory-direct quotation within 12 hours with full documentation confirmation.
Get Your Galvanized Square Steel Tube Quote With Mill Test Certificates
Send your specifications via email or WhatsApp to receive bulk pricing, coating verification details, and third-party inspection confirmation for your next project shipment.
Contact: Shandong Xin Jiyuan Special Steel Tube Co., Ltd
Tel: +86 531 8573 6315
Mobile/WhatsApp/WeChat: +86 188 5315 7756
Email: admin@sdxinjiyuan.com
