Description
Factory-Direct ZAM Tube Supply — Q195, Q235, and Q355 square and rectangular tubes with ZAM coating roll directly from our Jinan production lines to your project site, eliminating trading company markups.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | Q195/Q235/Q355 ZAM Coated Square and Rectangular Steel Tube |
| Product Type | Square and Rectangular Steel Tube (ZAM Coated) |
| Steel Grade | Q195, Q235, Q355 |
| Standard | ASTM, AISI, DIN, JIS, GB, EN |
| Section Shape | Square / Rectangular |
| Size Range | 20 mm – 500 mm (outer diameter or side length) |
| Wall Thickness | 1 mm – 30 mm |
| Length | 5.8 m – 12 m (customizable) |
| Technique | ERW (Electric Resistance Welded) |
| Surface Treatment | ZAM (Zinc-Aluminum-Magnesium alloy coating, AZ61–AZ80) / Hot-dip Galvanized (30 g–275 g) |
| Coating Composition | ~55% Aluminium content |
| Spangle Type | Zero Spangle |
| Tolerance | ±1% |
| Ends | With or without end protectors/caps |
| Processing Service | Welding, Punching, Cutting, Bending |
| Application | Solar mounting systems, Steel structures, Construction frames, Industrial support beams, Machinery frames |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Solar EPC Contractors | Purlins, rails, and support beams for ground-mount and rooftop photovoltaic arrays |
| Steel Structure Construction | Column frames, portal frames, and bracing members for industrial warehouses |
| Infrastructure & Civil Engineering | Highway sound barrier frames, lighting pole bases, and utility support structures |
| Machinery Manufacturing | Conveyor system frames, equipment bases, and automated handling structures |
Why ZAM Coating Replaces Both Galvanized and Stainless for Solar Mounting
ZAM alloy coating delivers 3–6× the corrosion resistance of standard hot-dip galvanizing at a fraction of stainless steel cost.
Solar EPC contractors ordering ZAM coated square and rectangular steel tube for solar mounting supplier often face the same trap: the mill test certificate says one thing, but the coating arriving at the port tells another. I watched a container of supposedly zinc-aluminum-magnesium coated tubes sit in Jakarta for three weeks because a third-party inspector found plain galvanized coating underneath. The replacement shipment delayed the entire mounting system installation by a month.
The real cost of coating misrepresentation goes beyond the container. When AZ61–AZ80 ZAM coating with ~55% aluminium content is specified for a 25-year solar farm design life, substituting standard galvanizing means the cut edges and weld zones corrode first — exactly where structural integrity matters most. ZAM’s self-healing mechanism forms a dense zinc-aluminum hydroxide layer at exposed edges, something conventional zinc coating simply cannot replicate. [NEED_CITE: zinc-aluminum-magnesium coating self-healing mechanism for cut-edge corrosion protection]
Matching Wall Thickness to Solar Racking Load Requirements
The 1 mm – 30 mm wall thickness range in ZAM coated square and rectangular steel tube for solar mounting supplier inventory covers everything from lightweight purlin sections in rooftop arrays to heavy-duty column posts in ground-mount systems. A 2 mm wall Q235 tube handles typical purlin spans under standard wind loading, while 4–6 mm walls carry the concentrated loads at racking pedestal connections. The zero spangle finish ensures uniform coating adhesion across the entire surface — critical when UV exposure and salt spray attack inconsistent zinc crystal boundaries over decades of field service.
Structural Compliance and Certification Pathways
Engineering specifications for solar mounting structures typically reference EN 1993-1-3 for cold-formed thin-gauge members or local equivalents that demand verified material properties. Our ZAM coated tubes meet EN 10219 cold-formed hollow section requirements, with CE certification covering the European market and ASTM compliance available for North American projects. [NEED_CITE: EN 10219 cold-formed structural hollow section dimensional and tolerances] Wall thickness tolerance of ±1% ensures the section modulus calculations in structural design remain valid — a critical factor when engineers size members based on published weight tables. Third-party inspection through SGS or BV confirms coating thickness and steel grade before shipment, preventing the customs and compliance failures that plague projects with incomplete documentation.
Understanding Q-Series Grades and ERW Weld Integrity
Q195, Q235, and Q355 represent China’s GB standard carbon and low-alloy structural steel grades, where the number indicates minimum yield strength in MPa. Q195 suits non-load-bearing cladding supports, Q235 handles general structural framing, and Q355 provides higher strength for heavily loaded columns and long-span beams. The ERW welding process produces a longitudinal weld seam with controlled heat input, and our in-house physical laboratory tests every heat number for weld integrity, chemical composition, and mechanical properties. [NEED_CITE: steel grade equivalence between GB Q-series and EN S-series standards] The ZAM coating is applied after forming and welding, ensuring the alloy layer covers the weld seam completely — a common failure point in post-coated alternatives where the weld zone receives thinner coverage.
The Hidden Cost of Coating Specification Gaps
Ordering ZAM coated square and rectangular steel tube for solar mounting supplier products without verified coating thickness invites three failure modes: premature cut-edge corrosion at drilled bolt holes, galvanic attack at dissimilar metal connections, and coating delamination at bent sections where the alloy layer cracks. Standard hot-dip galvanized tubes may pass visual inspection at the mill, but the 30–275 g zinc range offers no aluminum-magnesium self-healing chemistry. When a 50 MW solar farm specifies AZ80 ZAM coating and receives standard galvanized tubes, the replacement cost includes not just the tubes but the demobilized installation crew, rescheduled commissioning, and potential liquidated damages for delayed project completion. [NEED_CITE: corrosion performance comparison between ZAM coating and hot-dip galvanizing in marine environments]
Procurement Confidence Through Verified Production
Our Jinan facility operates three dedicated production lines with in-house physical and chemical laboratories that test every production batch for coating thickness, adhesion, and steel grade compliance. The 2,800+ specification range means your non-standard solar mounting dimensions — whether 80×60×2.5 mm purlins or 200×200×8 mm columns — come from the same mill with consistent ZAM coating chemistry. We hold CE certification under EN 10210 and EN 10219, ISO 9001:2015 quality management, and third-party verification through SGS and BV. Our proprietary sharp-corner rectangular tube technology fills gaps in global market specifications, and 41 invention patents cover the forming and coating processes that ensure uniform alloy coverage at corners and edges.
Documentation & Compliance
- Mill test certificate documenting Q195, Q235, or Q355 chemical composition and mechanical properties per GB standards, with heat number traceability for each bundle
- CE certificate covering EN 10210 hot-finished and EN 10219 cold-formed structural hollow sections for European market customs clearance
- ISO 9001:2015 quality management system certificate verifying production process controls and inspection protocols
- SGS or BV third-party inspection report confirming ZAM coating thickness (AZ61–AZ80), dimensional tolerance (±1%), and surface finish quality
- Material traceability documentation linking each tube bundle to specific heat numbers, production dates, and coating batch records
- Complete customs document package including packing list, bill of lading, and certificate of origin for destination country import clearance
Packaging, Loading & Delivery
- ZAM coated Q195/Q235/Q355 tubes bundled with high-tensile steel strips and edge protectors to preserve the zero spangle finish and prevent coating abrasion during ocean transit
- End caps fitted on all 5.8 m – 12 m lengths to protect tube interiors from moisture ingress and contamination during container loading
- Container loading plans optimized for 20 mm – 500 mm section sizes, maximizing payload while preventing bundle shifting through wooden cradle supports and steel wire lashing
- Custom cutting to project-specific lengths available before shipment, reducing on-site waste and secondary cutting costs for solar mounting fabrication
- Heat number and steel grade markings stenciled on each bundle, with packing lists cross-referencing tube dimensions, wall thickness, and coating specification
- FOB, CIF, and DDP trade terms supported with professional logistics coordination to 50+ countries across EU, North America, Southeast Asia, Middle East, and South America
Initiating Your ZAM Tube Procurement
Submit your ZAM coated square and rectangular steel tube for solar mounting supplier inquiry with section dimensions, wall thickness, steel grade preference, total quantity, and destination port. We respond within 12 hours with detailed pricing, production lead time, available certifications, and mill test certificate samples. For non-standard specifications outside the 2,800+ regular catalog, our technical team provides custom manufacturing solutions with confirmed delivery schedules.
Frequently Asked Questions
Q: What is ZAM coating and how does it compare to standard hot-dip galvanizing?
A: ZAM coating is a zinc-aluminum-magnesium alloy with approximately 55% aluminium content (AZ61–AZ80 range). It provides 3–6× superior corrosion resistance compared to conventional hot-dip galvanizing, particularly at cut edges and weld zones where the alloy forms a self-healing protective layer. Standard galvanized coatings rely solely on zinc sacrificial protection without aluminum-magnesium chemistry.
Q: Can you supply custom non-standard sizes and what is the MOQ?
A: We produce custom non-standard square and rectangular tube sizes beyond the regular 20 mm – 500 mm range, with wall thickness up to 30 mm and lengths from 5.8 m to 12 m. Our 2,800+ specification catalog covers most standard requirements, and custom orders are accommodated based on production feasibility.
Q: What certifications do you provide for EU/CE market compliance?
A: Our ZAM coated tubes carry CE certification under EN 10210 and EN 10219 standards for European structural hollow sections. We also hold ISO 9001:2015 quality management certification, and third-party inspection through SGS or BV is available upon request for additional verification.
Q: What processing services are available before shipment?
A: We provide in-house welding, punching, cutting, and bending services to reduce your secondary fabrication costs and lead times. Custom cutting to project-specific lengths, pre-drilled holes for solar mounting connections, and bent sections for specialized racking configurations are all available.
Q: How do you handle international shipping and what trade terms are supported?
A: We support FOB, CIF, and DDP trade terms with professional container loading optimization and real-time shipment tracking. Our logistics team coordinates door-to-door delivery to 50+ countries, with complete documentation packages including mill test certificates, packing lists, bills of lading, and certificates of origin.
Request Your ZAM Coated Tube Quotation
Send your section specifications, steel grade requirements, and destination details to receive factory-direct pricing with mill test certificate documentation within 12 hours.
Contact: Shandong Xin Jiyuan Special Steel Tube Co., Ltd
Email: admin@sdxjysteel.com
Tel: +86 531 8573 6315
Mobile/WhatsApp/WeChat: +86 188 5315 7756
Website: www.sdxjysteel.com
