Description
Factory-direct galvanized rectangular tubes — Q235 and Q345 grades hot dipped in our own galvanizing line, shipped with full CE EN10219 documentation to 50+ countries.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | Q235 Q345 Galvanized Rectangular Steel Tube |
| Product Type | Galvanized Rectangular Steel Tube |
| Steel Grade | Q235, Q235B, Q345, Q345B, SS400 |
| Standard | ASTM, API, CE, JIS, ISO 9001 |
| Section Shape | Square / Rectangular / Round |
| Wall Thickness | 0.5–200mm |
| Length | 6m / 6.4m / 12m (or customer required) |
| Technique | Cold Rolled / Hot Rolled |
| Surface Treatment | Zinc Coated (Hot Dipped Galvanized) |
| Tolerance | ±1% |
| Ends | Plain |
| Application | Construction structures / Bridges / Railways / Ships / Vehicles / Machinery manufacturing / Petrochemical industry / Marine development |
| MOQ | 5 Tons |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Construction & Infrastructure | High-rise building frames, bridge support structures, railway station canopies |
| Machinery Manufacturing | Conveyor system frames, automation equipment bases, crane booms |
| Petrochemical & Marine | Offshore platform handrails, chemical plant pipe racks, ship deck structures |
| Vehicle & Transport | Truck chassis frames, trailer body structures, heavy vehicle roll cages |
What Hot Dipped Galvanizing Adds to Q345 Rectangular Tubes in Coastal Projects
Salt spray exposure destroys untreated steel within months — hot dipped zinc coating extends service life to decades.
When sourcing Hot Dipped Galvanized Rectangular Steel Tube Q235 Q345 Supplier for marine environments or outdoor infrastructure, buyers often face material traceability gaps and inconsistent zinc layer thickness from fragmented suppliers. A single container with mixed heat numbers but no mill test certificates can trigger customs holds or fail third-party inspection at destination ports. [NEED_CITE: hot dip galvanizing coating thickness requirements per ISO 1461]
How Q235 and Q345 Grades Match Structural Load Requirements
Q235 serves general construction where yield strength requirements remain moderate — warehouse frames, scaffolding, and non-load-bearing partitions. Q345 steps in when structural engineers specify higher yield strength for bridge girders, crane runways, or heavy machinery bases. The Hot Dipped Galvanized Rectangular Steel Tube Q235 Q345 Supplier must provide clear grade separation on mill test certificates, as mixing Q235 into Q345-specified orders creates latent structural risks that surface only under load testing.
EN 10219 Compliance and EU Customs Clearance
European EPC contractors require Hot Dipped Galvanized Rectangular Steel Tube Q235 Q345 Supplier documentation conforming to EN 10219 for cold-formed welded structural hollow sections. The standard mandates chemical composition limits, mechanical property ranges, and dimensional tolerances that differ from ASTM A500. Without CE marking and EN 10219 test reports, shipments face rejection at EU ports regardless of physical quality. [NEED_CITE: EN 10219 cold-formed hollow section technical delivery conditions]
Steel Grade Equivalence Across Standards
Q235B roughly corresponds to S235JR under EN 10219, while Q345B aligns with S355J2H in yield strength class. However, equivalence stops at mechanical properties — impact testing requirements, elongation minimums, and carbon equivalent limits vary by standard. Buyers specifying Hot Dipped Galvanized Rectangular Steel Tube Q235 Q345 Supplier must confirm whether their project engineer accepts grade substitution or demands exact standard compliance. [NEED_CITE: steel grade equivalence between Chinese GB and European EN standards]
The Hidden Cost of Zinc Coating Thickness Variance
Hot dipped galvanizing should deliver 65–80 μm zinc coating for structural tubes, but some suppliers cut costs through electro-galvanizing or shortened dip times. Thin coating fails salt spray testing within 200 hours versus 500+ hours for proper hot dip. When Hot Dipped Galvanized Rectangular Steel Tube Q235 Q345 Supplier cannot provide coating thickness measurement reports, buyers risk premature corrosion in industrial atmospheres and coastal installations. [NEED_CITE: hot dip galvanized coating thickness per ISO 1461]
Why Project Procurement Teams Choose Xin Jiyuan
Our Jinan facility operates three dedicated production lines covering 2,800+ specifications with wall thickness up to 200mm — eliminating the need to source rectangular tubes, plates, and fabrication from separate vendors. The in-house physical and chemical laboratory issues mill test certificates for every heat number, while 41 invention patents include proprietary sharp-corner rectangular tube technology that meets tight radius requirements for architectural facades. CE EN10210/EN10219, ISO 9001, and SGS/BV verification ensure customs clearance across EU, North America, and Middle East markets. Professional loading plans optimize container weight distribution for 6m and 12m lengths, reducing freight cost per ton.
Documentation & Compliance
- Mill test certificate documenting Q235B/Q345B chemical composition and yield strength per GB/T 6728 and EN 10219 equivalence
- CE certificate confirming EN 10210/EN 10219 compliance for EU structural steel imports
- ISO 9001:2015 quality management certificate covering production and inspection processes
- SGS or BV third-party inspection report available for pre-shipment coating thickness and dimensional verification
- Material traceability by heat number linking each tube to ladle analysis and mechanical test results
- Customs documents including packing list, bill of lading, and certificate of origin for destination clearance
Packaging, Loading & Delivery
- Hot dipped galvanized rectangular tubes bundled with steel strips and edge protectors to preserve zinc coating during ocean transit
- Seaworthy packaging with waterproof paper wrapping for 6m and 12m lengths, preventing white rust formation in humid containers
- Container loading plans optimized for 20ft and 40ft OT frames, maximizing weight utilization for Q345 heavy-wall sections
- Plain ends capped with plastic protectors to prevent zinc damage and moisture ingress during storage
- Heat number stenciled on each tube end for site identification and mill test certificate cross-reference
- FOB Qingdao, CIF destination port, or DDP door-to-door delivery with real-time tracking to 50+ countries
Request Quotation with Mill Test Certificate
Submit your Hot Dipped Galvanized Rectangular Steel Tube Q235 Q345 Supplier requirements including section dimensions, wall thickness, length, quantity, and destination port. Our team responds within 12 hours with unit pricing, production lead time, and available certifications. Non-standard sizes and custom cutting services confirmed before contract signing.
Frequently Asked Questions
Q: Can Q235B substitute for S235JR in EN 10219 projects?
A: Q235B meets S235JR yield strength requirements, but EN 10219 mandates specific impact testing and elongation values. Confirm with your project engineer whether grade equivalence is acceptable or if exact EN compliance is required.
Q: What zinc coating thickness do you provide for hot dipped galvanized tubes?
A: Our hot dip galvanizing line delivers 65–80 μm coating thickness per ISO 1461, verified by magnetic gauge measurement and documented in third-party inspection reports upon request.
Q: Do you supply non-standard rectangular tube dimensions?
A: Yes. Beyond standard sizes, we produce custom dimensions within our 0.5–200mm wall thickness range. MOQ for non-standard sections is 5 tons, with proprietary sharp-corner technology available for tight radius requirements.
Q: How do you ensure material traceability for mixed orders?
A: Each tube is stenciled with heat number linking to mill test certificate showing chemical composition and mechanical properties. Mixed heat shipments include separate test reports for full traceability.
Q: What certifications do you provide for EU market entry?
A: We supply CE certificate per EN 10210/EN10219, ISO 9001 quality certificate, and SGS/BV third-party inspection reports. All documents support customs clearance and project compliance verification.
Get Your Hot Dipped Galvanized Rectangular Steel Tube Quote Today
Send specifications and quantity to receive pricing with mill test certificate within 12 hours.
Contact: Shandong Xin Jiyuan Special Steel Tube Co., Ltd
Email: admin@sdxjysteel.com
WhatsApp: +86 188 5315 7756
