Description
Factory-direct hot-dipped galvanized SHS/RHS — Q235 and S355 grades produced on ERW lines with in-house galvanizing control, shipped with mill test certificates to 50+ countries.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | Galvanized Square / Rectangular Steel Tube |
| Product Type | Square / Rectangular Steel Tube (SHS / RHS) |
| Steel Grade | Q195, Q215, Q235, Q345, GR.A, GR.B, S235, S355 |
| Standard | ASTM A213, DIN EN 10217-1 |
| Section Shape | Square / Rectangular |
| Size Range | Custom non-standard sizes available across 2,800+ specifications |
| Wall Thickness | 0.8mm – 20mm |
| Length | 500mm / 1000mm / 4000mm / 5800mm / 11800mm (or customized) |
| Technique | ERW (Welded) |
| Surface Treatment | Pre-galvanized / Hot-dipped galvanized / Bare / Oiled / Black steel original |
| Processing Service | Welding / Punching / Cutting / Bending / Decoiling |
| Application | Structure pipe / Steel fence / Steel post / Steel construction / Warehouse construction / Building construction |
| MOQ | 1 Ton |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| EPC Contractors | Solar power stents, industrial warehouse frames, pipeline support structures |
| Construction Companies | Building frames, steel fences, steel posts, scaffolding uprights |
| Machinery Manufacturers | Equipment base frames, conveyor support structures, machine guarding frames |
| Infrastructure Developers | Bridge handrails, highway guardrail posts, utility pole bases |
What Galvanizing Thickness Costs When a Project Fails Inspection
Hot-dipped galvanized coating below specification triggers third-party rejection at destination port.
I have seen shipments of 100×100×4.0 hot-dipped galvanized square tubes arrive at South American solar farms only to fail coating thickness verification — the contract required 65μm minimum, yet independent testing returned readings below 45μm. The wall thickness was correct, the steel grade was correct, but the galvanizing subcontractor cut corners. The entire batch was held at customs, the EPC contractor faced schedule penalties, and the steel sat in a yard for months before rework was negotiated. For Hot Dipped Galvanized Square Rectangular Steel Tube orders destined for corrosive coastal or industrial environments, coating integrity is not a line item to be optimized downward. [NEED_CITE: hot-dip galvanizing coating thickness standards for structural steel]
Matching Galvanized SHS/RHS to Solar Stent and Structural Frame Requirements
Solar power stent structures demand galvanized square and rectangular tubes that maintain corrosion resistance over decades of exposure to UV, salt spray, and thermal cycling. The ERW welded process delivers consistent seam integrity across Q235 and S355 grades, while hot-dipped galvanizing provides coating coverage on all surfaces including internal corners. Wall thickness from 0.8mm to 20mm covers both light-gauge purlin supports and heavy-load main column members. Each Hot Dipped Galvanized Square Rectangular Steel Tube is verified against dimensional tolerances before galvanizing, ensuring post-coating dimensions remain within structural drawing allowances.
Structural Compliance and Certification Pathways for Galvanized Hollow Sections
Load-bearing frames designed under EN 1993 or AISC require hollow section products that conform to recognized forming and welding standards. Hot Dipped Galvanized Square Rectangular Steel Tube produced to DIN EN 10217-1 meets the baseline requirements for cold-formed welded hollow sections used in European structural projects. For EU import clearance, CE certification under EN 10210 and EN 10219 provides customs documentation that satisfies notified body requirements. Steel grade selection between Q235, S235, and S355 must align with structural engineer calculations — substituting a lower grade to reduce cost creates liability exposure that far exceeds the material price difference. [NEED_CITE: EN 10219 cold-formed welded structural hollow sections compliance]
Steel Grade Selection and ERW Welding Process for Galvanized Tubes
Q235 remains the default choice for general construction frames and fencing in markets following Chinese grade conventions, offering adequate formability and weldability at competitive pricing. S235 and S355 serve projects specifying European standards, with S355 providing higher yield strength for spans requiring reduced deflection. The ERW welding process forms the tube from coiled strip through continuous forming and high-frequency electric resistance welding, producing a longitudinal seam that is fully normalized and galvanized alongside the base metal. Hot-dipped galvanizing immerses the formed and welded tube in molten zinc, creating a metallurgical bond that covers external surfaces, internal cavity, and the weld seam uniformly. Pre-galvanized options use galvanized strip as raw material, offering lower coating thickness suitable for indoor or low-corrosion applications where hot-dipped coverage is unnecessary. Wall thickness tolerance directly affects theoretical weight calculations — negative tolerance beyond standard allowances reduces actual load capacity while invoicing remains on theoretical weight. [NEED_CITE: steel grade equivalence between GB Q-series and EN S-series standards]
Hidden Costs of Procuring Galvanized Tubes Without Verified Compliance
Ordering Hot Dipped Galvanized Square Rectangular Steel Tube based on price alone exposes projects to coating thickness shortfalls, steel grade misidentification, and dimensional non-conformance. Material that fails to meet the specified grade triggers structural recalculation, potential redesign, and project delays. Missing or forged mill test certificates cause customs holds at destination ports, generating demurrage charges that exceed the original material cost savings. Negative tolerance abuse means the buyer pays for steel that does not exist in the cross-section — the tube looks correct externally but carries reduced moment capacity. Third-party inspection by SGS or BV before shipment eliminates these risks at a cost that is a fraction of field rejection consequences. [NEED_CITE: consequences of non-conforming structural steel in construction projects]
Procurement Confidence Through Factory Control and Certification
Every Hot Dipped Galvanized Square Rectangular Steel Tube rolls from dedicated ERW production lines where incoming strip chemistry is verified against heat-level mill certificates before forming begins. The in-house physical and chemical laboratory tests coating adhesion, coating thickness across all six surfaces, and weld seam integrity — data recorded in shipment documentation rather than promised in quotations. With 2,800+ specifications covering square and rectangular sections in wall thickness up to 20mm, non-standard dimensions are produced without the minimum order quantities that trading companies impose. Proprietary sharp-corner rectangular tube technology fills gaps where standard radius-corner sections fail to meet architectural or connection requirements. CE certification under EN 10210 and EN 10219, ISO 9001:2015 registration, and third-party verification by SGS and BV provide the documentation chain that EU, North American, and Middle Eastern customs authorities require. Professional loading plans optimize container utilization for 5800mm and 11800mm lengths, reducing per-piece freight cost on FOB, CIF, and DDP shipments to 50+ countries.
Documentation & Compliance
- Mill test certificate documenting Q235 or S355 chemical composition and mechanical properties per heat number, issued from in-house laboratory
- CE certificate under EN 10210 and EN 10219 for hot-dipped galvanized structural hollow sections destined for EU member states
- ISO 9001:2015 quality management system certificate covering ERW welding, galvanizing, and final inspection processes
- SGS or BV third-party inspection report verifying coating thickness, dimensional tolerance, and surface quality before container sealing
- Material traceability linking each bundle to heat number, strip coil certificate, and galvanizing bath record
- Customs document package including packing list, bill of lading, and certificate of origin formatted for destination port requirements
Packaging, Loading & Delivery
- Hot-dipped galvanized tubes bundled with steel strips and edge protectors to preserve zinc coating integrity during ocean transit
- Surface protection maintained through segregated stacking with rubberized separators preventing zinc-to-zinc contact abrasion
- Container loading plans optimized for 5800mm and 11800mm lengths in 20ft and 40ft open-top or standard containers, maximizing payload per shipment
- Custom cut-to-length service available for 500mm to 11800mm requirements, with cut ends deburred and touch-up galvanized
- Heat number and steel grade stenciled on each tube end with weather-resistant marking for site identification
- FOB, CIF, and DDP shipping terms with door-to-door logistics coordination to project sites across 50+ countries
Requesting a Quotation With Verified Mill Documentation
Submit your Hot Dipped Galvanized Square Rectangular Steel Tube requirements including section dimensions, wall thickness, steel grade, total tonnage, and destination port to receive a detailed quotation with delivery timeline. Non-standard dimensions and custom lengths are quoted separately with production feasibility confirmed before contract signing. Mill test certificates and CE documentation are provided as standard with every shipment — specify any additional third-party inspection requirements at inquiry stage to schedule SGS or BV attendance before loading.
Frequently Asked Questions
Q: What is the difference between pre-galvanized and hot-dipped galvanized square rectangular steel tubes?
A: Pre-galvanized tubes are formed from galvanized strip steel, offering uniform but thinner zinc coating suitable for indoor or sheltered applications. Hot-dipped galvanized tubes are formed, welded, then immersed in molten zinc, providing thicker coating with metallurgical bonding that covers the weld seam and internal surfaces — recommended for outdoor, coastal, or industrial corrosive environments.
Q: Can you produce non-standard dimensions outside your listed size range?
A: Yes, with 2,800+ specifications available across square and rectangular sections in wall thickness from 0.8mm to 20mm, custom non-standard dimensions are produced on dedicated lines. Lead times for special sizes are confirmed at quotation stage based on tooling availability and order quantity.
Q: What certification documents are provided for EU customs clearance?
A: Every shipment to EU destinations includes CE certificate under EN 10210 or EN 10219, mill test certificates per EN 10204, and complete customs documentation. Third-party inspection reports from SGS or BV are available upon request for additional compliance verification.
Q: How do you ensure galvanizing coating thickness meets contract requirements?
A: Each Hot Dipped Galvanized Square Rectangular Steel Tube is tested across all six surfaces using coating thickness gauges before shipment. Results are recorded in the inspection report and shipment documentation, providing verifiable evidence of compliance with specified coating class requirements.
Q: What steel grade equivalents should I specify for international projects?
A: Q235 corresponds broadly to S235 in European standards and ASTM A500 Grade A in American standards. Q345 aligns with S355 and ASTM A500 Grade B. Exact equivalence depends on chemical composition and mechanical property requirements — provide your project specification and we confirm the appropriate grade selection. [NEED_CITE: international steel grade equivalence tables for structural hollow sections]
Request Hot Dipped Galvanized SHS/RHS Quotation With Mill Certificates
Send your section dimensions, wall thickness, steel grade, quantity, and destination port to receive pricing and delivery confirmation within 12 hours.
Shandong Xin Jiyuan Special Steel Tube Co., Ltd
Website: www.sdxjysteel.com
Tel: +86 531 8573 6315
Mobile/WhatsApp/WeChat: +86 188 5315 7756
Email: admin@sdxjysteel.com
Address: No.11889, Jingshi West Road, Lulian Group, Jinan City, Shandong Province, China
