Description
Factory-direct ASTM A500 galvanized rectangular steel tube — ERW welded and hot dip galvanized in-house, every batch tested with coating thickness gauges before loading.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | ASTM A500 Galvanized Rectangular Steel Tube |
| Product Type | Galvanized Square and Rectangular Steel Tube |
| Steel Grade | Q195, Q235, Q345 (Q355) |
| Standard | ASTM A500, GB/T 6728, JIS G3466, EN 10219 |
| Section Shape | Square / Rectangular |
| Size Range (Side Length) | 20–500 mm |
| Wall Thickness | 1–30 mm |
| Length | 5.8–12 m |
| Technique | ERW (Electric Resistance Welded) |
| Surface Treatment | Hot Dip Galvanized (Zinc Coating 30–275 g/m²) |
| Ends | Plain (with or without caps) |
| Processing Service | Welding, Punching, Cutting, Bending |
| Application | Steel structures, Construction frames, Machinery, Scaffolding, Furniture, Greenhouse structures |
| MOQ | 1 Ton |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Construction & Infrastructure | Building structural frames, scaffolding systems, load-bearing columns |
| Machinery & Equipment | Machine base frames, industrial platform supports, conveyor structures |
| Agriculture & Greenhouse | Corrosion-resistant greenhouse skeletons, irrigation support frames |
| Furniture & Interior | Structural frames for metal furniture, display rack supports |
Why Zinc Coating Thickness Decides Whether Your Shipment Clears Site Inspection
A 30-micron gap between quoted and actual galvanizing can get an entire container rejected by the site supervisor.
I have seen this happen more than once. A commercial complex project in Dubai ordered hot dip galvanized rectangular tubes with a contractual minimum of 65μm zinc coating. When the cargo arrived, SGS re-inspection showed only 35μm across multiple samples. The site engineer rejected the entire batch. The buyer had to find a local paint shop to补救, costing over eighty thousand dollars in losses and weeks of delay. [NEED_CITE: hot dip galvanizing coating thickness standards for structural steel] That is why every ASTM A500 galvanized rectangular steel tube we ship gets measured with a coating thickness gauge on the production floor before a single piece enters the container. Quality uncertainty at the galvanizing stage does not show up in a visual check — it shows up at customs or at the site inspection, where the cost of failure multiplies.
Matching Structural Load Requirements Across Humid and Corrosive Environments
Hot dip galvanizing at 30–275 g/m² zinc coating provides a sacrificial corrosion barrier that outperforms painted or oiled black tubes in outdoor and high-humidity conditions. For greenhouse structures in Southeast Asia or coastal scaffolding in the Middle East, the zinc layer protects the Q235 or Q345 base metal from atmospheric corrosion without requiring additional maintenance coatings. The ERW welding seam undergoes the same galvanizing bath as the parent metal, ensuring uniform coverage across the entire ASTM A500 galvanized rectangular steel tube — corners, weld lines, and internal surfaces alike. Wall thickness from 1 mm to 30 mm covers everything from light-duty furniture frames to heavy-load structural columns, and our 2,800+ specification inventory means standard sizes ship from ready stock while custom dimensions run through our three production lines.
Engineering Compliance and Certification Requirements for Galvanized Structural Tubes
Structural frames designed under ASTM A500 require verified chemical composition and mechanical properties traceable to each heat number. [NEED_CITE: ASTM A500 structural tubing specification requirements] For projects targeting European markets, the same product range conforms to EN 10219 cold-formed hollow section standards, with CE certification covering EN 10210 and EN 10219 product families. Site engineers in the Gulf region typically demand third-party inspection reports from SGS or BV alongside original mill test certificates — missing documentation triggers customs holds and project compliance failures. Our in-house three-stage inspection process covers dimensional tolerance, coating thickness, and weld integrity before any ASTM A500 galvanized rectangular steel tube leaves the factory floor. [NEED_CITE: third-party inspection requirements for steel imports in Middle East construction]
Steel Grade Selection and ERW Welding Process for Structural Integrity
The Q195–Q345 grade range covers a broad spectrum of structural demands. Q195 serves light-duty applications where formability matters more than load-bearing capacity. Q235 remains the workhorse grade for general construction frames and scaffolding, offering balanced strength and weldability. Q345 (Q355) steps up yield strength for heavier structural columns and machinery bases where deflection limits tighten. The ERW welding process produces a longitudinal seam through electric resistance heating without filler metal, creating a weld zone that — after hot dip galvanizing — integrates into the overall corrosion protection system. Unlike seamless tubes that carry higher cost for pressure applications, ERW galvanized rectangular tubes deliver structural performance at competitive pricing for non-pressure uses. [NEED_CITE: ERW versus seamless steel tube selection for structural applications] Negative tolerance on wall thickness is controlled within standard limits, and we provide both theoretical and actual weight data on every mill test certificate so procurement teams can verify pricing accuracy.
The Hidden Cost of Buying Galvanized Tubes Without Verified Coating Data
Ordering ASTM A500 galvanized rectangular steel tube based on price alone, without confirmed zinc coating thickness and mill test certificates, exposes projects to three failure modes. First, under-galvanized tubes pass visual inspection at the port but fail site coating tests, triggering rejection and costly local rework. Second, missing or falsified mill certificates cause customs clearance delays that stall entire project timelines. Third, unverified steel grades may not meet the structural load calculations engineered into the building design, creating safety liability. [NEED_CITE: consequences of non-compliant steel materials in construction projects] These costs never appear in the initial purchase invoice — they surface months later at the job site, where remediation expenses dwarf the original savings from choosing an unverified supplier.
Procurement Confidence Built on Factory Control and Documentation
We manufacture the ASTM A500 galvanized rectangular steel tube on our own production lines in Jinan, which means factory-direct pricing without trader markups and volume discount programs for recurring orders. Our in-house理化 laboratory tests every heat for chemical composition and mechanical properties, producing original mill test certificates that travel with each shipment. For buyers requiring independent verification, we coordinate SGS or BV third-party inspection at the factory before loading. The full product range — square and rectangular tubes from 20 mm to 500 mm, wall thickness 1–30 mm, zinc coating 30–275 g/m² — ships from ready stock for standard sizes, while custom dimensions and non-standard lengths run through production within typical lead times. Our export team handles container loading optimization, ensuring heavy galvanized tubes are packed to maximize weight per container while protecting the zinc coating from transit damage.
Documentation & Compliance
- Mill test certificate documenting Q195/Q235/Q345 chemical composition and mechanical properties per ASTM A500, traceable by heat number
- CE certificate covering EN 10210 and EN 10219 standards for hot dip galvanized hollow sections entering European markets
- ISO 9001:2015 quality management certificate covering the full production process from ERW welding to hot dip galvanizing
- SGS or BV third-party inspection report available upon request, verifying zinc coating thickness and dimensional tolerance before shipment
- Material traceability documentation linking each ASTM A500 galvanized rectangular steel tube bundle to its original heat number and production batch
- Complete customs document package including packing list, bill of lading, and certificate of origin formatted for destination port requirements
Packaging, Loading & Delivery
- Galvanized rectangular tubes bundled with steel strips and edge protectors to preserve the zinc coating during ocean transit and prevent surface scratches
- Seaworthy packaging with waterproof wrapping available for Q195–Q345 grade tubes shipping to humid coastal destinations
- Container loading plans optimized for 5.8–12 m lengths, maximizing weight utilization while maintaining balance for 20-foot and 40-foot containers
- Custom cutting service available to deliver ASTM A500 galvanized rectangular steel tube in project-specific lengths, reducing on-site waste
- Heat number and steel grade markings stenciled on each bundle for site identification and inspection traceability
- FOB, CIF, and DDP shipping terms supported, with professional export documentation handling for customs clearance at destination ports
Getting Your Quotation Started with Verified Specifications
Send your requirements — section dimensions, wall thickness, steel grade, zinc coating specification, quantity, and destination port — and receive a detailed quotation within 12 hours including volume pricing, production lead time, and available mill test certificate documentation. For non-standard dimensions or custom lengths outside the 20–500 mm range, our engineering team reviews feasibility and provides a tailored production plan. Confirm your certification needs — CE, SGS, BV — at the inquiry stage so documentation travels with the first shipment.
Frequently Asked Questions
Q: What is the difference between Q235 and Q345 steel grades for galvanized rectangular tubes?
A: Q235 offers balanced strength and formability suitable for general construction frames and scaffolding, while Q345 provides higher yield strength for heavier structural applications like load-bearing columns and machinery bases. Both grades undergo the same hot dip galvanizing process with zinc coating from 30–275 g/m².
Q: Can you provide SGS or BV third-party inspection for galvanized rectangular steel tubes?
A: Yes, third-party inspection from SGS or BV is available upon request. We coordinate the inspection at our factory before loading, covering zinc coating thickness measurement, dimensional verification, and visual weld inspection. The inspection report ships with your documentation package.
Q: What is the minimum order quantity for ASTM A500 galvanized rectangular steel tube?
A: The MOQ is 1 Ton, supporting both trial orders and full-container bulk purchases. Standard sizes ship from ready stock, while custom dimensions and non-standard lengths follow typical production lead times.
Q: How do you ensure zinc coating meets the specified 30–275 g/m² range?
A: Every batch undergoes coating thickness measurement using digital gauges on the production floor before packaging. Results are documented on the mill test certificate, and third-party verification is available for buyers requiring independent confirmation.
Q: Do you offer custom cutting and processing services?
A: Yes, we provide cutting, punching, bending, and welding services for ASTM A500 galvanized rectangular steel tube. Custom lengths within the 5.8–12 m range are available to reduce on-site fabrication waste.
[Request Your ASTM A500 Galvanized Rectangular Steel Tube Quotation]
Submit your specifications, steel grade, quantity, and destination port to receive factory-direct pricing with mill test certificate documentation within 12 hours.
Shandong Xin Jiyuan Special Steel Tube Co., Ltd
Website: www.sdxinjiyuan.com
Tel: +86 531 8573 6315
Mobile/WhatsApp/WeChat: +86 188 5315 7756
Email: admin@sdxinjiyuan.com
Address: No.11889, Jingshi West Road, Lulian Group, Jinan City, Shandong Province, China
