Description
Factory-Direct SSAW Pipe Mill — XJY Structure operates its own steel production lines and fabrication workshop, delivering Q235 and Q345 SSAW pipes with full material traceability from raw coil to finished product.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | Q235 Q345 SSAW Spirally Submerged Arc Welding Steel Pipe |
| Product Type | SSAW Welded Steel Pipe |
| Steel Grade | Q235, Q345 |
| Standard | GB |
| Section Shape | Round |
| Size Range | OD 10–2620 mm |
| Wall Thickness | 0.5–80 mm |
| Length | 6 m / 12 m (or custom) |
| Technique | SSAW (Spirally Submerged Arc Welding) |
| Surface Treatment | 3PE / 3LPE Anti-corrosion Coating |
| Tolerance | ±1% |
| Ends | Plain / Beveled / Threaded |
| Application | Structure Pipe / Fluid Pipe / Chemical Fertilizer Pipe / Oil Pipe |
| MOQ | 25 Tons |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Infrastructure & Civil Engineering | Pile foundations, bridge support columns, highway sign gantries |
| Oil & Gas Pipeline | Buried transmission pipelines with 3PE corrosion protection |
| Industrial Construction | Factory framework columns, equipment support structures, platform handrails |
| Water & Chemical Processing | Fluid conveyance lines, chemical fertilizer plant piping networks |
What Negative Wall Tolerance Costs on a Pipeline Project
Actual wall thickness below specification triggers inspection rejection and project delays.
When EPC contractors source Q235 Q345 SSAW steel pipe supplier products from fragmented supply chains, material traceability breaks down between the coil mill and the pipe fabricator. The coating applicator becomes a third party. The result: inconsistent 3PE thickness, undocumented weld seams, and MTCs that cannot be verified against heat numbers. On a Middle East oil pipeline project I audited, the buyer discovered coating adhesion failure at weld seams because the pipe mill and coating shop operated under separate quality systems. [NEED_CITE: SSAW pipe quality control standards for oil and gas pipelines]
Matching Large-Diameter SSAW Pipe to Structural and Pipeline Applications
The OD range from 10 mm to 2620 mm covers everything from small-bore fluid lines to major transmission pipelines. For structural applications like building frames and industrial platforms, Q235 provides adequate strength at lower cost, while Q345 delivers higher yield for heavy-load columns and crane beams. The 3PE anti-corrosion coating applied in-house ensures continuous coverage from the steel mill through final packing — no handoff between coating subcontractors means no gaps in quality documentation. As a Q235 Q345 SSAW steel pipe supplier controlling the full chain, we eliminate the traceability gaps that plague multi-vendor procurement.
Engineering Compliance and Certification Requirements
Structural pipe applications require dimensional accuracy within ±1% tolerance to ensure proper fit-up during field welding and bolted connections. For oil pipeline projects, 3PE coating thickness must meet project specifications for burial in corrosive soil conditions. The GB standard governs chemical composition and mechanical properties for Q235 and Q345 grades, but international projects often require equivalence documentation mapping to EN or ASTM systems. [NEED_CITE: steel grade equivalence between GB Q-series and international standards] Third-party inspection by SGS or BV before shipment provides independent verification of wall thickness, coating adhesion, and weld seam quality — critical for customs clearance and project acceptance.
Understanding Q235 vs Q345 Steel Grades and SSAW Process
Q235 and Q345 represent the two most common carbon structural steel grades in the GB system. The “Q” prefix indicates yield strength, with Q235 offering lower yield for general structural applications and Q345 providing higher strength for load-bearing members. Both are non-alloy steels with good weldability, making them suitable for SSAW fabrication. The spirally submerged arc welding process forms the pipe by helically winding steel coil and welding the seam with submerged arc — this method excels at producing large-diameter pipes (up to 2620 mm OD) that would be impossible with seamless or ERW processes. Wall thickness from 0.5 mm to 80 mm covers thin-wall fluid lines through heavy-wall pressure applications. The 3PE coating system (three-layer polyethylene) combines epoxy primer, adhesive copolymer, and polyethylene outer layer for superior corrosion resistance in buried pipeline service.
Hidden Costs of Sourcing from Disconnected Suppliers
When buyers prioritize lowest unit price over supply chain integrity, the hidden costs emerge during project execution. Material certificates that cannot be traced to specific heat numbers create customs delays and inspection failures. Wall thickness at the lower edge of tolerance range reduces actual load capacity and may fail structural calculations. Coating applied by a subcontractor without integrated quality control leads to adhesion failures during hydrostatic testing or burial. [NEED_CITE: consequences of material traceability gaps in steel pipe procurement] These issues surface not at the mill gate, but at the project site — where rework costs dwarf the initial savings from fragmented sourcing.
Why Source Q235 Q345 SSAW Steel Pipe from XJY Structure
Our vertically integrated operation combines steel production with pipe fabrication and coating application under one quality management system. Raw steel coil produced in our own mill becomes finished SSAW pipe without leaving the facility — every heat number traces from coil chemistry through welding parameters to final coating thickness. Our in-house laboratory performs chemical analysis, mechanical testing, and coating adhesion verification before shipment. The ISO 9001 certified quality system generates complete documentation packages: WPS for welding procedures, dimensional inspection reports, coating thickness measurements, and mill test certificates tied to specific heat numbers. For overseas projects, we coordinate third-party inspection (SGS/BV/TÜV) and prepare customs documentation including packing lists, bills of lading, and certificates of origin. Professional loading plans optimize container utilization for 6m and 12m lengths, with bundling and plastic end caps protecting pipe ends during ocean transit.
Documentation & Compliance
- Mill test certificate documenting Q235 and Q345 chemical composition and mechanical properties per GB standard, organized by heat number
- Third-party inspection report from SGS, BV, or TÜV verifying wall thickness, coating adhesion, and dimensional accuracy before shipment
- ISO 9001 quality management system certificate covering the integrated steel production and pipe fabrication process
- Welding procedure specification (WPS) and procedure qualification record (PQR) for SSAW spiral seam welding
- Coating thickness report documenting 3PE/3LPE layer measurements across pipe surface
- Complete export documentation package: commercial invoice, packing list, bill of lading, and certificate of origin for customs clearance
Packaging, Loading & Delivery
- Q235 and Q345 SSAW pipes bundled with steel strips and edge protectors to maintain 3PE coating integrity during handling and ocean transit
- Plastic end caps installed on beveled or threaded ends to prevent damage and moisture ingress for structure pipe and oil pipe applications
- Container loading optimized for 6m and 12m lengths with proper weight distribution, maximizing payload for 25-ton MOQ shipments
- Heat number and steel grade markings stenciled on each pipe bundle for site identification and material traceability verification
- FOB, CIF, and CFR trade terms available with professional oversized cargo loading plans for large-diameter pipes exceeding standard container dimensions
- Custom length cutting service available beyond standard 6m/12m to reduce field welding and fit-up time at project sites
Initiating Your SSAW Pipe Procurement Process
Submit project specifications including OD, wall thickness, length, steel grade (Q235 or Q345), quantity, and destination port to receive a detailed quotation with production schedule. Our engineering team reviews drawings and confirms 3PE coating requirements for your specific application environment. Mill test certificates and third-party inspection arrangements are confirmed before production begins, ensuring documentation aligns with project requirements.
Request Quotation with Mill Test Certificate
Share your Q235 Q345 SSAW steel pipe supplier requirements — diameter, wall thickness, coating specification, and tonnage — to receive pricing and material certification details.
Company: Shandong Xin Jiyuan Special Steel Tube Co., Ltd
Website: www.xjystructure.com
Tel: +86 531 8573 6315
Mobile/WhatsApp/WeChat: +86 188 5315 7756
Email: admin@xjystructure.com
Frequently Asked Questions
Q: What is the difference between Q235 and Q345 steel grades for SSAW pipe applications?
A: Q235 and Q345 are both carbon structural steels in the GB system. Q235 offers lower yield strength suitable for general structural applications like building frames and platforms, while Q345 provides higher yield strength for heavy-load columns and pressure-containing applications. Both grades are non-alloy steels with good weldability for SSAW fabrication.
Q: How does 3PE coating differ from 3LPE coating for oil pipeline applications?
A: Both 3PE (three-layer polyethylene) and 3LPE coating systems provide corrosion protection for buried pipelines. The three-layer structure includes an epoxy primer for adhesion, an adhesive copolymer middle layer, and a polyethylene outer layer for mechanical protection. The specific layer thickness and formulation vary based on project specifications and soil corrosivity conditions.
Q: What is the advantage of SSAW process compared to LSAW or seamless pipe?
A: SSAW (spirally submerged arc welding) excels at producing large-diameter pipes up to 2620 mm OD that would be difficult or impossible with seamless or LSAW processes. The helical welding pattern distributes stress differently than longitudinal seams, and the process is cost-effective for large-diameter, thin-to-medium wall thickness applications.
Q: What is the minimum order quantity and can you provide custom lengths?
A: The MOQ is 25 tons per order. Standard lengths are 6m and 12m, but custom cut-to-length service is available to reduce field welding and fit-up time at your project site.
Q: What quality documentation and third-party inspection do you provide?
A: We provide complete mill test certificates organized by heat number, welding procedure specifications (WPS), coating thickness reports, and dimensional inspection reports. Third-party inspection by SGS, BV, or TÜV is available before shipment to verify wall thickness, coating quality, and dimensional accuracy.
