Description
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | Q195 Q235 Q345 Hot Dipped Galvanized Square Rectangular Steel Tube |
| Product Type | Galvanized Square & Rectangular Steel Tube |
| Steel Grade | Q195, Q235, Q345, 10#, 20#, 45#, 16Mn, ASTM A53 (Grade A/B), ASTM A500 (Grade B/C/D), St37, St42, St35.4, St52.4, ST35 |
| Standard | BS EN, GB, AISI, ASTM, DIN, JIS |
| Section Shape | Square / Rectangular |
| Size Range | 10mm – 1000mm (side length / outer diameter) |
| Wall Thickness | 0.6mm – 28mm |
| Length | 1m – 12m |
| Technique | ERW (Hot Rolled / Cold Rolled) |
| Surface Treatment | Hot Dipped Galvanized (Zinc Coating 30–275g/m²); also available: Bared, Oiled, Color Paint, 3PE |
| Ends | Plain / Beveled / Threaded with Couplings or Sockets; Plastic caps and steel rings available |
| Application | Construction and architecture / Structural engineering / General fabrication / Manufacturing / Frames / Trailers / Automobile chassis / Industrial equipment / Machine parts / Sign posts / Agricultural equipment / Home appliances |
| MOQ | 1 Ton |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Construction & Architecture | Building frames, glass curtain wall supports, decorative structural elements, facade steel framing |
| Structural Engineering | Bridge handrails, highway guardrail posts, industrial platform structures |
| Machinery Manufacturing | Conveyor frames, equipment bases, machine part housings |
| Agricultural Equipment | Greenhouse structural frames, irrigation support posts, machinery protective guards |
| Signage & Infrastructure | Highway sign posts, street lighting poles, traffic signal supports |
What Zinc Coating Thickness Really Means for Your Project Timeline
A 30g/m² coating fails inspection in coastal environments; 275g/m² survives decades.
When procurement teams specify hot dipped galvanized square and rectangular steel tubes without understanding zinc coating weight classes, the consequences appear months later — white rust staining on facade elements, premature corrosion at weld joints, or outright rejection during third-party inspection at destination port. I have seen containers held at customs because the mill certificate showed pre-galvanized coating when the contract demanded hot dipped galvanizing with minimum 65g/m² zinc. The rework cost exceeds the original material savings by a wide margin [NEED_CITE: hot dipped galvanizing zinc coating thickness standards for structural applications].
Matching Wall Thickness to Structural Load Requirements
The Hot Dipped Galvanized Square Rectangular Steel Tube range covers wall thicknesses from 0.6mm to 28mm, spanning applications from light-duty furniture frames to heavy-load industrial equipment bases. For structural engineering projects requiring EN 10219 compliance, the 3mm to 12mm wall thickness range provides optimal balance between load-bearing capacity and material efficiency. The ERW manufacturing process ensures consistent dimensional tolerance across the full length, critical when tubes must align precisely in welded frame assemblies. Our in-house laboratory verifies every batch against EN 10219 cold-formed hollow section requirements before release [NEED_CITE: EN 10219 cold-formed hollow section dimensional tolerance requirements].
Certification Pathways for EU and North American Markets
European construction projects demand CE marking under EN 10210 or EN 10219, while North American buyers require ASTM A500 or A53 compliance documentation. The Hot Dipped Galvanized Square Rectangular Steel Tube we produce carries Lloyd’s CE certification for EN 10210/EN 10219 standards, Singapore FPC approval, and full ISO 9001:2015 quality management coverage. This certification package eliminates customs clearance delays that plague shipments lacking proper mill test certificates or carrying incorrect standard references. Steel grade equivalence between Q235/Q345 and EN S235JR/S355JR or ASTM A500 Grade B/C requires explicit documentation to prevent material substitution disputes during project handover [NEED_CITE: steel grade equivalence between EN and ASTM standards].
Understanding Steel Grade Selection for Galvanized Tubes
The Q195, Q235, and Q345 steel grades represent increasing yield strength levels in the Chinese GB standard system, directly corresponding to load-bearing requirements. Q195 serves light structural applications where formability matters more than strength, while Q345 provides higher yield strength for heavy-load industrial frames and bridge components. The ASTM A500 Grade B/C/D and EN S235JR/S355JR equivalents allow international procurement teams to specify familiar designations while receiving material meeting their project’s structural calculations. Hot dipped galvanizing adds corrosion protection without compromising the base metal’s mechanical properties, though coating thickness selection must account for service environment severity — indoor applications tolerate 30g/m² zinc, while coastal or industrial atmospheres require 120g/m² to 275g/m² for long-term protection.
Hidden Costs of Incorrect Specification or Missing Documentation
Purchasing Hot Dipped Galvanized Square Rectangular Steel Tube based solely on price per ton invites expensive surprises: zinc coating below contract minimum triggers rejection at destination, forcing return shipment or local re-galvanizing at triple the original cost. Missing CE documentation blocks EU customs clearance, stranding containers at port while demurrage charges accumulate. Negative tolerance exceeding standard limits reduces actual load capacity below engineering calculations, creating structural safety liability. Material traceability gaps prevent proper weld procedure qualification when field modifications become necessary, delaying project completion while waiting for mill verification [NEED_CITE: structural steel certification requirements for construction projects].
Why Procurement Teams Choose Our Production Facility
We operate three dedicated production lines covering over 2,800 specification combinations, eliminating the need to source from multiple suppliers when projects require mixed sizes and wall thicknesses. Our patented sharp-corner rectangular tube technology provides 90-degree edges for architectural applications where traditional rounded-corner tubes create aesthetic and connection problems. The in-house physical and chemical laboratory performs dimensional verification, mechanical testing, and coating thickness measurement before shipment, with full mill test certificates issued for every heat number. We hold Lloyd’s CE certification for EN 10210/EN 10219, Singapore FPC approval, and complete ISO 9001:2015 documentation, ensuring smooth customs clearance across 50+ export destinations. Professional container loading with anti-damage measures prevents bending and zinc coating abrasion during ocean transit, while custom cutting and marking services reduce on-site labor costs.
Documentation & Compliance
- Mill test certificate documenting Q195/Q235/Q345 chemical composition and mechanical properties per GB standard, with EN/ASTM equivalence statements
- CE certificate under EN 10210/EN 10219 for European construction projects, issued by Lloyd’s Register
- ISO 9001:2015 quality management system certificate covering full production process
- SGS or BV third-party inspection report available upon request, verifying dimensional tolerance and zinc coating thickness
- Material traceability by heat number linking each tube to specific mill test certificate and production batch
- Complete customs documentation including packing list, bill of lading, and certificate of origin
Packaging, Loading & Delivery
- Hot dipped galvanized tubes bundled with steel strips and edge protectors to preserve zinc coating during ocean transit
- Plastic end caps installed on all tube openings to prevent moisture ingress and internal corrosion during storage
- Container loading optimized for 6m and 12m lengths with wooden separators preventing tube-to-tube contact and zinc abrasion
- Heat number and steel grade marked on every tube with stenciled identification for site traceability
- FOB, CIF, and DDP shipping terms available with professional loading supervision ensuring damage-free arrival
- Custom length cutting available within 1m to 12m range, reducing on-site waste and labor costs
Securing Your Quotation with Complete Technical Documentation
Submit your specification requirements including tube dimensions, wall thickness, steel grade preference, zinc coating weight, quantity, and destination port to receive detailed quotation with mill test certificate sample and production lead time. Our technical team reviews specifications against EN 10219 dimensional tolerance requirements and confirms steel grade equivalence documentation before contract signing, eliminating specification disputes during project execution.
Request Technical Quotation with Mill Test Certificate
Provide your Hot Dipped Galvanized Square Rectangular Steel Tube specifications and receive quotation within 12 hours, including material certification documentation and shipping options.
Contact Information:
- Website: www.sdxjypipe.com
- Tel: +86 531 8573 6315
- Mobile/WhatsApp/WeChat: +86 188 5315 7756
- Email: admin@sdxjypipe.com
- Address: No.11889, Jingshi West Road, Lulian Group, Jinan City, Shandong Province, China
Frequently Asked Questions
Q: What is the difference between 30g/m², 120g/m², and 275g/m² zinc coating for corrosion resistance?
A: Zinc coating weight directly determines service life in corrosive environments. The 30g/m² coating suits indoor applications with minimal moisture exposure, providing basic rust prevention during construction. The 120g/m² coating handles moderate outdoor exposure for 10-15 years in non-industrial atmospheres. The 275g/m² coating provides maximum protection for coastal environments, industrial areas with chemical exposure, or applications requiring 25+ year service life without maintenance.
Q: How do Q235/Q345 grades compare to ASTM A500 and EN S235JR/S355JR?
A: Q235 corresponds to EN S235JR and ASTM A500 Grade A in yield strength range, suitable for general structural applications. Q345 matches EN S355JR and ASTM A500 Grade B/C, providing higher yield strength for heavy-load structures. We provide explicit equivalence statements on mill test certificates to satisfy engineering specifications across different standard systems.
Q: Can you produce non-standard dimensions with low MOQ?
A: Yes, our production lines cover over 2,800 specification combinations including custom side lengths from 10mm to 1000mm, wall thicknesses from 0.6mm to 28mm, and lengths from 1m to 12m. The MOQ remains 1 Ton even for non-standard sizes, with typical production lead times of 15-25 days for custom specifications.
Q: Do your products carry CE marks for EU market entry?
A: Yes, our Hot Dipped Galvanized Square Rectangular Steel Tube carries Lloyd’s CE certification under EN 10210 and EN 10219 standards, meeting European Construction Products Regulation requirements. We also hold Singapore FPC approval and complete ISO 9001:2015 documentation for regulated markets worldwide.
Q: How do you prevent bending and surface damage during container loading?
A: We use professional loading procedures with wooden separators between tube layers, edge protectors on bundle corners, and plastic end caps on all openings. For long-length tubes exceeding 6m, we optimize container stowage to prevent movement during ocean transit. Our loading team documents each container with photos before sealing, providing loading supervision reports for quality verification.
Get Your Hot Dipped Galvanized Steel Tube Quotation Today
Send your specifications including dimensions, steel grade, zinc coating requirements, and quantity to receive detailed pricing with complete mill test certificate documentation within 12 hours.
Contact Information:
- Website: www.sdxjypipe.com
- Tel: +86 531 8573 6315
- Mobile/WhatsApp/WeChat: +86 188 5315 7756
- Email: admin@sdxjypipe.com
