Description
Factory-direct Q235 ERW welded steel pipe — produced from our own steel mill with full heat-number traceability from billet to finished galvanized pipe.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | Q235 ERW Welded Steel Pipe |
| Product Type | ERW Welded Steel Pipe |
| Steel Grade | Q235, Q195-Q345 |
| Standard | GB, API, BSI, CE, JIS, ISO 9001 |
| Section Shape | Round |
| Size Range | Outer Diameter 26.9 – 310 mm |
| Length | 6 m, 6.4 m |
| Technique | ERW |
| Surface Treatment | Galvanized Coating |
| Tolerance | ±1% |
| Ends | Plain |
| Application | Fluid transport, Boiler systems, Construction structure |
| MOQ | 1 Ton |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Construction & Infrastructure | Building frames, warehouse roof trusses, scaffolding uprights |
| Industrial Piping | Fluid transport lines, cooling water circuits, compressed air mains |
| Energy & Utilities | Boiler feed lines, heat exchanger casings, support stanchions |
| EPC Projects | Pipe racks, structural bracing, equipment support frames |
What Negative Tolerance Costs on a Galvanized Pipe Order
A ±1% OD tolerance on Q235 ERW welded steel pipe means the difference between passing site inspection and shipping the entire container back.
Overseas buyers sourcing welded steel pipes from fragmented suppliers frequently encounter dimensional drift that compounds across a project. When a fabricator sources raw material from third-party mills without controlling the production chain, wall thickness variation and ovality at the weld seam become invisible risks until the pipe reaches the job site. The监理 rejects the batch, the contractor demands replacement, and the project schedule collapses — all because nobody verified tolerance at the point of manufacture. [NEED_CITE: EN 10219 cold-formed hollow section dimensional tolerance requirements]
Matching Galvanized ERW Pipe to Structural and Fluid Applications
The Q235 ERW welded steel pipe in 26.9-310mm outer diameter range serves dual roles across construction and industrial projects. For structural frameworks — warehouse columns, pipe rack supports, and bracing members — the galvanized coating provides corrosion resistance in humid or coastal environments without field painting. For fluid transport applications, the ERW weld seam delivers consistent internal bore and pressure integrity suitable for cooling water and compressed air circuits. Our own steel mill produces the Q235 and Q195-Q345 grades used in these pipes, meaning every heat number traces back to our billet casting line rather than an unverified third-party supplier.
Engineering Compliance and Certification Requirements
Structural applications for Q235 ERW welded steel pipe must satisfy dimensional and material standards recognized by the project’s governing code. For European markets, CE marking under EN 10219 confirms compliance with cold-formed welded structural hollow sections. For North American projects, API and BSI certifications alongside ASTM equivalence documentation satisfy procurement specifications. The galvanized coating thickness must meet corrosion environment classifications — heavier zinc layers for industrial or marine exposure, standard coating for interior or sheltered use. Plain ends allow field welding, threading, or grooved coupling per site connection requirements. [NEED_CITE: steel grade equivalence between GB Q235 and international standards ASTM A53 EN 10219]
Understanding Q235 Steel Grade and ERW Welding Process
Q235 belongs to the Chinese GB standard carbon structural steel series, with yield strength positioning it between Q195 (lighter duty) and Q345 (higher strength low-alloy). This grade balances formability with weldability, making it suitable for ERW pipe production where the steel strip passes through forming rolls and the longitudinal seam is welded by high-frequency electric resistance. The ERW process produces a firm, narrow weld bead with minimal heat-affected zone, preserving the base metal’s mechanical properties along the seam. Galvanizing after welding — rather than using pre-galvanized strip — ensures the weld zone receives full zinc coverage, eliminating the corrosion vulnerability that occurs when the weld seam is exposed. The ±1% outer diameter tolerance across the 26.9-310mm range reflects controlled forming and welding parameters, critical for projects requiring precise fit-up with flanges, couplings, or structural connectors.
Hidden Costs of Sourcing Unverified Welded Pipe
Purchasing Q235 ERW welded steel pipe from suppliers who cannot provide mill test certificates with heat-number traceability creates compounding project risks. Material that fails to meet the declared steel grade triggers rejection during third-party inspection — SGS or BV testing at the port of discharge. Pipes with excessive negative tolerance on wall thickness pass visual inspection but fail structural load calculations, forcing replacement after delivery. Missing or forged certification documents delay customs clearance, generating demurrage charges that exceed the original pipe cost. [NEED_CITE: material traceability and mill test certificate requirements for structural steel imports]
Why Procure Q235 ERW Pipe from Xin Jiyuan
Our vertical integration eliminates the material sourcing gap that creates most quality failures in welded pipe procurement. We produce the Q235 and Q195-Q345 steel grades in our own mill, then fabricate the ERW welded pipe and apply galvanized coating within the same facility — one production chain, one quality system, one point of accountability. Every Q235 ERW welded steel pipe carries a mill test certificate traceable to the original heat number from our billet casting line. Our fabrication workshop holds certified welding procedures (WPS/PQR) and qualified welders under AWS and EN standards, with in-process NDT testing and dimensional inspection at every production stage. We maintain over 2,800 specifications in raw material inventory, enabling custom length cutting and non-standard outer diameter requests without the multi-week delays typical of fragmented suppliers. Professional export packing and container loading optimization ensure the galvanized coating arrives intact after ocean transit.
Documentation & Compliance
- Mill test certificate documenting Q235 chemical composition and mechanical properties per GB standard, with heat number traceability to our own steel production facility
- CE certificate confirming compliance with EN 10219 for welded structural hollow sections, required for European market customs clearance
- ISO 9001 quality management certificate covering the full production process from raw steel to galvanized finished pipe
- SGS or BV third-party inspection report available upon request, covering dimensional verification, coating thickness measurement, and weld seam quality
- Material traceability documentation linking each pipe bundle to its original heat number, WPS records, and NDT test results
- Complete customs export documents including packing list, bill of lading, and certificate of origin for destination-country clearance
Packaging, Loading & Delivery
- Q235 ERW welded steel pipe bundled with steel strips and edge protectors to preserve the galvanized coating surface during handling and ocean transit
- Galvanized coating protected by waterproof wrapping and wooden cradle supports for 6 m and 6.4 m lengths, preventing zinc layer damage from contact with bare steel or container floors
- Container loading optimized for 26.9-310mm outer diameter round pipes, with nested bundling configurations maximizing payload per 20ft and 40ft containers
- Custom length cutting available per project specifications within the 6 m and 6.4 m standard range, with cut ends deburred and coated to prevent edge corrosion
- Each bundle marked with heat number, steel grade Q235, outer diameter, wall thickness, and production date for site identification and traceability verification
- FOB, CIF, and DDP shipping terms available with professional oversized cargo loading plans and complete export documentation tracking to destination port
Starting Your Q235 ERW Pipe Procurement
Submit your project drawings or specifications — including outer diameter, wall thickness, steel grade, quantity, and destination port — to receive a detailed quotation with production schedule and mill test certificate preview. Our engineering team reviews shop drawings for material optimization and fabrication sequencing before production begins, reducing the RFI delays that typically extend welded pipe lead times. Confirm your certification requirements (CE, API, BSI, JIS) and third-party inspection preferences (SGS/BV) so we prepare the complete documentation package alongside your Q235 ERW welded steel pipe order.
Frequently Asked Questions
Q: Can you provide mill test certificates with heat-number traceability for Q235 ERW welded steel pipe?
A: Yes. Every pipe bundle carries a mill test certificate documenting Q235 chemical composition and mechanical properties, with heat number traceability back to our own steel production facility. The certificate covers the full production chain from billet casting through ERW welding and galvanized coating.
Q: What is the steel grade equivalence between Q235 and international standards?
A: Q235 corresponds broadly to ASTM A53 Grade A and S235JR under EN 10219 in terms of carbon content and yield strength range. We provide equivalence documentation for project specifications requiring international standard compliance, and our engineering team can advise on grade selection based on your project’s governing code. [NEED_CITE: steel grade equivalence between GB Q235 and ASTM A53 EN 10219]
Q: What galvanized coating thickness do you provide for different environments?
A: Galvanized coating thickness varies based on the corrosion environment classification of your project. Standard coating suits interior or sheltered applications, while heavier zinc layers are specified for industrial, coastal, or high-humidity environments. We provide coating thickness measurement reports as part of the quality documentation package.
Q: Can you supply custom lengths or non-standard outer diameters within the 26.9-310mm range?
A: Yes. Our own steel mill and fabrication workshop allow custom length cutting and non-standard outer diameter requests with MOQ flexibility starting from 1 Ton. We maintain over 2,800 specifications in raw material inventory, reducing the lead time typical of fragmented suppliers who must source custom sizes from third parties.
Q: What third-party inspection and certification options are available for export shipments?
A: We support SGS and BV third-party inspection covering dimensional verification, coating thickness measurement, weld seam NDT testing, and material traceability audits. Certification options include CE (EN 10219), API, BSI, JIS, and ISO 9001, with complete customs documentation prepared for destination-country clearance.
Get Your Q235 ERW Welded Steel Pipe Quote
Send your project specifications — outer diameter, wall thickness, steel grade, quantity, and destination port — to receive a detailed quotation with mill test certificate preview and production schedule within 24 hours.
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
Address: No.11889, Jingshi West Road, Lulian Group, Jinan City, Shandong Province, China
