Description
Factory-direct galvanized hollow sections — In-house steel mill producing Q235 and Q345 grades with hot-dipped and pre-galvanized coating options, eliminating third-party material sourcing gaps for SHS/RHS orders.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | Galvanized Square and Rectangular Steel Tube |
| Product Type | Square and Rectangular Steel Tube (SHS / RHS) |
| Steel Grade | Q235, Q345, S235JR, S275JR, STK400, STK500 |
| Standard | GB/T 3091, BS1387, EN39, EN1139, ASTM A53, JIS G3444 |
| Section Shape | Square / Rectangular |
| Size Range (Side Length) | 21.3–3048 mm |
| Wall Thickness | 0.8–50 mm |
| Length | Random Length / Fixed Length / SRL / DRL / Customized |
| Technique | Hot Rolled Based / ERW |
| Surface Treatment | Pre-painted galvanized (zinc 60–120 g/m²), Hot-dipped galvanized (zinc 120–500 g/m²), Electroplated galvanized (zinc 10–50 g/m²) |
| Ends | Plain end / Beveled end / Threaded end |
| Application | Steel structure projects, low-pressure liquid delivery, construction frames, scaffolding, machinery, furniture |
| MOQ | 5 tons |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Steel Structure & Construction | Building frames, warehouse columns and beams, logistics center support structures |
| Scaffolding & Temporary Works | Scaffold uprights, ledger tubes, base plate connections |
| Industrial Piping | Low-pressure water, gas, and oil delivery lines |
| Machinery & Equipment | Machine frames, conveyor supports, equipment bases |
| Furniture & Interior | Structural frames for industrial furniture, display racks, mezzanine platforms |
Zinc Coating Thickness Determines Whether Your Shipment Clears Site Inspection
A galvanized square and rectangular steel tube supplier who cannot prove coating weight at the mill gate is gambling with your project acceptance.
Overseas buyers routinely discover zinc coating shortfalls only after containers arrive at port. Third-party inspectors measure thirty-something microns against a contract specifying sixty, and the entire batch gets held at the construction site. Material traceability gaps compound the problem — when the fabricator sources raw tubes from multiple third-party mills, heat number chains break, and EN 10204/3.1B certificates become meaningless paperwork. [NEED_CITE: zinc coating thickness testing methods for hot-dipped galvanized steel]
Matching Coating Weight to Corrosion Environment for Structural Frames
Selecting the right galvanized square and rectangular steel tube requires aligning zinc coating mass with the actual exposure conditions your project will face. Hot-dipped galvanizing at 120–500 g/m² handles outdoor structural frames, warehouse portals, and coastal logistics centers where salt-laden air accelerates corrosion. Pre-painted galvanized at 60–120 g/m² serves indoor construction frames and machinery bases where aesthetic finish matters alongside moderate protection. Electroplated options at 10–50 g/m² fit furniture and interior applications where corrosion demands are minimal. Our own mill controls every coating stage in-line, so the zinc weight on the certificate matches what arrives on your jobsite — no rebatching from unverified sub-suppliers.
Structural Compliance and Steel Grade Selection Across Markets
Engineering specifications for galvanized SHS and RHS vary significantly by destination market. European projects require EN 10219 cold-formed or EN 10210 hot-finished compliance with CE marking, while North American tenders reference ASTM A53 or A500. Southeast Asian and Middle Eastern EPC firms often accept GB/T 3091 or JIS G3444 with mill test certificates. Steel grade selection directly affects load-bearing capacity: Q235 and S235JR serve general structural frames, while Q235 and S275JR provide higher yield strength for heavily loaded columns and long-span trusses. Wall thickness tolerance becomes critical when theoretical weight calculations drive budget estimates — negative tolerance beyond standard limits means less steel than paid for. [NEED_CITE: EN 10219 dimensional tolerance requirements for cold-formed hollow sections]
Steel Grade Equivalence and ERW Process Fundamentals
Q235 maps closely to S235JR in the European system and roughly to ASTM A283 Grade C, while Q345 corresponds to S355JR/J0 and ASTM A572 Grade 50. These equivalences are approximate — actual chemical composition and impact testing requirements differ between standards, so specifying by project standard rather than cross-referencing avoids acceptance disputes. The ERW (Electric Resistance Welded) process used for most galvanized square and rectangular steel tube production creates a longitudinal weld seam suitable for structural and low-pressure applications. Hot rolled based production handles heavier wall thicknesses up to 50 mm, while ERW covers the full range from 0.8 mm thin-wall tubes to medium structural sections. Surface treatment choice — hot-dipped versus pre-galvanized versus electroplated — reflects a trade-off between corrosion resistance, coating adhesion, and cost. Hot-dipped zinc metallurgically bonds to the steel substrate, providing sacrificial protection even at cut edges and drill holes, making it the default for outdoor structural steel.
Hidden Costs of Sourcing from Unverified Galvanized Square and Rectangular Steel Tube Supplier Channels
Pricing that undercuts the market by significant margins usually reflects one of three shortcuts: sub-specification wall thickness, inadequate zinc coating, or missing material certification. When galvanized tubes arrive at a Middle Eastern warehouse with coating weight below contract specification, the buyer faces re-galvanizing costs that exceed the original savings — or worse, structural rejection by the project engineer. Customs authorities in the EU increasingly demand EN 10204/3.1B certificates with verifiable heat numbers; shipments without proper documentation face delays or return. [NEED_CITE: EU customs requirements for steel product certification and CE marking]
Why Project Procurement Teams Consolidate Galvanized Hollow Section Orders Here
Our vertically integrated operation — owning both the steel production facility and the fabrication workshop — means every galvanized square and rectangular steel tube ships with full material traceability from our own melt heat to the finished bundle. The mill covers over 2,800 specifications across square and rectangular profiles, so a single purchase order for mixed sizes on a warehouse project sources from one production line under one quality system. Our in-house laboratory issues mill test certificates per EN 10204/3.1B documenting chemical composition and mechanical properties for each heat. Third-party inspection through SGS or BV is available at our facility before loading, giving buyers independent verification without flying auditors to China. Professional packing with edge protectors preserves the galvanized coating during ocean transit, and our loading team plans container stowage to maximize weight utilization for heavy-wall sections while protecting surface finish.
Documentation & Compliance
- Mill test certificate documenting Q235/Q345/S235JR/S275JR chemical composition and mechanical properties per GB/T 3091, EN39, or ASTM A53 as specified
- Zinc coating weight test report confirming hot-dipped (120–500 g/m²), pre-painted (60–120 g/m²), or electroplated (10–50 g/m²) treatment per order specification
- Dimensional inspection report covering side length, wall thickness, and length tolerance for each production batch
- SGS or BV third-party inspection report available upon request for independent pre-shipment verification
- Full export documentation package including packing list, bill of lading, and certificate of origin for customs clearance
- Material traceability by heat number linking each bundle to its mill test certificate
Packaging, Loading & Delivery
- Galvanized SHS/RHS bundles secured with steel strips and fitted with plastic end caps to protect threaded or beveled ends during transit
- Edge protectors applied to all bundles to prevent zinc coating damage from steel strap contact during ocean shipping
- Container loading plans optimized by wall thickness and side length — heavy-wall Q345 sections loaded at bottom with lighter pre-galvanized tubes stacked above
- Fixed length and DRL orders cut to project-specified dimensions with saw-cut precision, eliminating on-site cutting waste
- Heat number and steel grade stenciled on each bundle for site identification and traceability verification
- FOB, CIF, and DDP terms available with door-to-door logistics coordination for project sites across the Middle East, Southeast Asia, Africa, and South America
Getting Your Galvanized SHS/RHS Quotation Moving
Submit your project drawings or specification list including section sizes, wall thickness, steel grade, zinc coating requirement, and total tonnage to receive a detailed quotation with production schedule and mill test certificate commitment. For non-standard dimensions or mixed-size warehouse orders, our engineering team reviews your requirements and confirms feasibility within one working day.
Request Your Galvanized Hollow Section Quotation Today
Send your specifications, steel grade, coating requirement, and destination port to receive pricing, production timeline, and sample mill test certificates.
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
Frequently Asked Questions
Q: What is the difference between hot-dipped, pre-painted, and electroplated galvanized coating for square and rectangular tubes?
A: Hot-dipped galvanizing applies zinc at 120–500 g/m² through immersion in molten zinc, creating a metallurgical bond suitable for outdoor and corrosive environments. Pre-painted galvanized coating provides 60–120 g/m² zinc with an additional paint layer for aesthetic and moderate protection needs. Electroplated galvanizing delivers 10–50 g/m² zinc for indoor applications where corrosion exposure is minimal.
Q: How do Q235 and Q345 steel grades compare to S235JR and S275JR for structural projects?
A: Q235 and S235JR are closely matched as general-purpose structural grades. Q345 and S275JR offer higher yield strength for heavily loaded structural members. Exact equivalence depends on chemical composition limits and impact testing requirements specified in the project standard — always specify by the standard your project requires rather than cross-referencing.
Q: Can you produce non-standard sizes for galvanized square and rectangular tubes, and what is the MOQ?
A: We produce custom side lengths and wall thicknesses within our range of 21.3–3048 mm side length and 0.8–50 mm wall thickness. The minimum order quantity for custom dimensions is 5 tons. Our mill covers over 2,800 specifications, so most project-specific sizes fall within standard production capability.
Q: What quality documentation do you provide with each shipment of galvanized tubes?
A: Each shipment includes mill test certificates per EN 10204/3.1B documenting chemical composition and mechanical properties by heat number, zinc coating weight test reports, dimensional inspection reports, and full export documentation. Third-party inspection through SGS or BV is available at our facility before loading.
Q: How are galvanized square and rectangular tubes packed to prevent coating damage during shipping?
A: Bundles are secured with steel strips fitted with edge protectors to prevent strap contact with the zinc surface. Plastic end caps protect beveled and threaded ends. Container loading plans separate heavy-wall sections from lighter tubes to prevent coating abrasion during ocean transit.
Start Your Galvanized SHS/RHS Procurement
Share your project drawings, steel grade, coating specification, and destination port — our team responds within 24 hours with pricing, production schedule, and sample documentation.
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
