Description
Factory-direct bulk supply — 3 production lines running simultaneously with monthly capacity exceeding 20,000 tons of galvanized welded square and rectangular steel tubes across 2,800+ specifications.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | Galvanized Welded Square/Rectangular Steel Tube |
| Product Type | Square and Rectangular Steel Tube (SHS/RHS) |
| Steel Grade | Q195, Q235, Q235B, Q355, S275, S275JR, A53, ST37, SGCC, CGCC, DX51D |
| Standard | ASTM, JIS, API, BIS, CE, ISO 9001, KS, PVOC, RoHS, SABS, Saso, SNI, SONCAP, TISI |
| Section Shape | Square / Rectangular |
| Size Range | Wall Thickness 1.2 – 20 mm |
| Length | 1 – 12 m or as customer request |
| Technique | Hot Rolled Based / Welded |
| Surface Treatment | Galvanized (Z30 – Z180) |
| Tolerance | ±1% |
| Ends | Plain / Cut |
| Application | Steel structures, Making pipes, Cutting sheets, Making containers, Making corrugated sheets, Making fences, Making small tools, Boiler pipe |
| MOQ | 15 Tons |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Construction & Infrastructure | Structural frames, scaffolding systems, perimeter fencing, support columns for commercial buildings |
| Industrial Fabrication | Container chassis, corrugated sheet purlins, machinery frames, conveyor structures |
| Energy & Utilities | Boiler pipe assemblies, solar panel mounting structures, wind farm support brackets |
| Agricultural & Storage | Greenhouse framing, grain silo supports, equipment shelters |
Where Missing Mill Certificates Stall Your Container at Port
Every batch of galvanized welded square rectangular steel tube ships with original mill test certificates — no exceptions.
I have watched entire container loads of steel tubes sit at destination ports for weeks because the supplier could not produce proper documentation. Customs officers in markets across Africa and the Middle East routinely hold galvanized steel shipments pending material traceability verification. When your galvanized welded square rectangular steel tube arrives without heat number tracking or chemical composition records, the cargo becomes a liability rather than an asset. [NEED_CITE: customs documentation requirements for galvanized steel imports in developing markets]
Beyond documentation gaps, inconsistent zinc coating thickness creates field failures that do not surface until months after installation. A Z30 coating might suffice for indoor structural framing, but the same specification on outdoor fencing in coastal humidity invites accelerated corrosion complaints from your end buyers.
Matching Coating Weight to Environmental Exposure
Selecting the correct galvanized welded square rectangular steel tube starts with understanding where the product will live after installation. For indoor structural applications such as warehouse framing or mezzanine supports, Z30 to Z60 coating provides adequate corrosion protection at lower material cost. Outdoor applications including fencing, scaffolding, and solar mounting structures demand Z120 to Z180 coating to withstand rain, UV exposure, and atmospheric pollutants over the design life of the project. Our inventory spans the full Z30–Z180 range across 2,800+ specifications, allowing buyers to consolidate mixed-coating orders into a single shipment rather than sourcing from multiple suppliers.
Structural Compliance and Certification Requirements
Engineering specifications for galvanized welded square rectangular steel tube frequently reference EN 10219 for cold-formed welded hollow sections or ASTM A500 for structural tubing in North American projects. The Q355 and S275JR grades we supply meet the chemical composition and dimensional tolerance requirements of these standards, with ±1% tolerance maintained through skin-pass processing. CE certification under EN 10210/EN 10219 is mandatory for structural steel entering European markets, while SONCAP and PVOC certifications govern imports into Nigeria and Kenya respectively. [NEED_CITE: EN 10219 dimensional tolerance requirements for welded hollow sections] Third-party inspection through SGS or BV is available on request for projects requiring independent verification before shipment.
Steel Grade Selection Across International Standards
The galvanized welded square rectangular steel tube we produce covers three major grading systems: Chinese Q-series (Q195, Q235, Q235B, Q355), European S-series (S275, S275JR), and American ASTM (A53). The Q-series follows GB/T standards where the number after “Q” indicates minimum yield strength in MPa. S275JR corresponds to EN 10025 with guaranteed impact toughness at room temperature, making it suitable for structural applications in temperate climates. ASTM A53 covers both structural and pressure applications with Type E (ERW) and Type S (seamless) variants. For buyers sourcing across regions, understanding grade equivalence prevents specification errors — Q235B approximates S275JR in yield strength, while Q355 aligns with S355JR in structural performance. [NEED_CITE: steel grade equivalence between Chinese GB, European EN, and American ASTM standards]
The Hidden Cost of Wrong Coating and Tolerance Choices
Ordering galvanized welded square rectangular steel tube with incorrect zinc coating or accepting excessive negative tolerance creates costs that appear long after the purchase order is signed. Undersized wall thickness reduces load-bearing capacity below engineering design assumptions, triggering re-inspection demands and potential structural reinforcement expenses. [NEED_CITE: impact of negative tolerance on structural steel load capacity] Thin or uneven galvanizing leads to premature rust formation at cut edges and weld joints, generating warranty claims and replacement costs that far exceed the initial price difference between coating grades. Missing or forged mill certificates result in customs holds, demurrage charges, and project schedule delays that compound daily.
Why Bulk Buyers Source Galvanized Welded Square Rectangular Steel Tube from Xin Jiyuan
Factory-direct pricing eliminates trading company markups, with volume discount programs structured for long-term procurement partners. Our three production lines operate simultaneously, delivering monthly output exceeding 20,000 tons with standard sizes held in ready stock for urgent dispatch. Every production run undergoes three-stage in-house quality inspection, and original mill test certificates accompany each batch — not photocopies, not templates, but traceable documents tied to specific heat numbers. We maintain 2,800+ specifications in inventory covering square tubes, rectangular tubes, round pipes, steel plates, and section steel, enabling consolidated container loading that reduces per-unit freight costs. CE, ISO 9001:2015, and FPC certifications ensure compliance across European, African, and Middle Eastern markets. Custom orders for non-standard dimensions or specific coating weights ship within typical production lead times, with flexible MOQ accommodating both trial orders and full-container bulk purchases.
Documentation & Compliance
- Mill test certificate documenting Q235B/Q355/S275JR chemical composition and mechanical properties per applicable standard
- CE certificate confirming compliance with EN 10210/EN 10219 for structural hollow sections entering European markets
- ISO 9001:2015 quality management certificate covering the full production process from raw material to finished galvanized tube
- SGS or BV third-party inspection report available for projects requiring independent verification of coating weight and dimensional accuracy
- Material traceability by heat number linking each galvanized welded square rectangular steel tube to its original production batch
- Complete customs documentation including packing list, bill of lading, and certificate of origin formatted for destination port requirements
Packaging, Loading & Delivery
- Galvanized welded square rectangular steel tube bundled with steel strips and edge protectors to preserve the zinc coating during ocean transit and prevent corner damage
- Zero spangle finish with non-oiled surface shipped in seaworthy packaging, with optional protective film available for high-gloss appearance requirements
- Container loading optimized for 1–12 m lengths with layered separation to maximize payload while maintaining weight distribution across 20ft and 40ft containers
- Custom cutting to exact project lengths available, reducing on-site waste and labor costs for fabrication contractors
- Heat number and steel grade stenciled on each bundle for rapid identification during unloading and inventory management
- FOB, CIF, and DDP delivery terms with professional export team handling documentation, customs clearance coordination, and real-time shipment tracking
Start Your Procurement with Full Specifications
Submit your requirements including section dimensions, wall thickness, steel grade, coating weight, quantity, and destination port to receive a competitive bulk quotation with volume pricing and delivery timeline. Our team responds within hours with detailed specifications confirmation and available mill test certificate samples for your quality review.
Request Your Galvanized SHS/RHS Quote with Mill Test Certificates
Send your specifications via email to admin@sdxinjiyuan.com or contact us directly at +86 188 5315 7756 (WhatsApp/WeChat) to begin your procurement process with factory-direct pricing and complete documentation support.
Frequently Asked Questions
Q: What is the difference between Q235B and S275JR for galvanized welded square rectangular steel tube?
A: Q235B follows Chinese GB/T standards with minimum yield strength of 235 MPa, while S275JR follows European EN 10025 with minimum yield strength of 275 MPa and guaranteed impact toughness at room temperature. Both grades are available in our galvanized welded square rectangular steel tube range, with selection depending on your project specification requirements and destination market standards.
Q: How do I choose between Z30 and Z180 galvanized coating for my project?
A: Z30 coating suits indoor applications with minimal moisture exposure such as warehouse framing and interior structural supports. Z180 coating provides maximum corrosion resistance for outdoor applications including fencing, scaffolding, solar mounting structures, and coastal environment installations. We stock the full Z30–Z180 range and can advise on optimal coating selection based on your specific environmental conditions.
Q: What documentation do you provide with each shipment of galvanized welded square rectangular steel tube?
A: Every batch ships with original mill test certificates documenting chemical composition and mechanical properties, tied to specific heat numbers for full traceability. We also provide CE certificates for European markets, ISO 9001:2015 quality certificates, and complete customs documentation including packing lists, bills of lading, and certificates of origin. SGS or BV third-party inspection reports are available on request.
Q: Can you produce non-standard dimensions and what is the minimum order quantity?
A: Yes, we produce custom dimensions beyond standard catalog sizes with typical production lead times for non-standard orders. Our minimum order quantity is 15 tons, which accommodates both trial orders for new buyers and full-container bulk purchases for established procurement programs.
Q: How do you optimize container loading for mixed-size galvanized tube orders?
A: Our export team designs container loading plans that maximize payload while maintaining proper weight distribution and preventing product damage during transit. We combine multiple specifications into single containers using layered separation and edge protection, reducing per-unit freight costs for buyers consolidating diverse project requirements from one source.
