Description
Factory-Direct ERW Round Pipe Supply — In-house physical and chemical lab testing on every heat, with original mill test certificates provided before shipment.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | Carbon Steel ERW Round Pipe |
| Product Type | ERW Round Steel Pipe |
| Steel Grade | Q235, Q235B, Q345, Q345B, SS400, A53, A106, A269, S235JR, S275JR, S355J2, API 5L Gr.A/B/X42/X52/X60/X70 |
| Standard | ASTM A53, ASTM A106, API 5L, EN 10217-1, JIS G3466, GB/T 6728 |
| Section Shape | Round |
| Size Range | OD 14–1200 mm |
| Wall Thickness | 1–50 mm |
| Length | 6 m / 12 m or customized |
| Technique | ERW / Hot Rolled / Cold Rolled |
| Surface Treatment | Black painted / Varnished / Galvanized (Hot-Dip / Electro) / 3LPE / 3LPP coated / Oiled |
| Tolerance | ±1% |
| Ends | Plain / Beveled / Threaded |
| Application | Fluid transport / Gas pipeline / Oil pipeline / Construction structural frameworks / Scaffolding / Machinery / Shipbuilding marine piping |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| EPC Contractors & Construction | Structural frameworks, scaffolding systems, pipe rack supports for industrial plants |
| Oil & Gas / Energy | Transmission pipelines, gathering lines, fluid and gas transport under API 5L and ASTM A106 |
| Machinery Manufacturers | Hydraulic cylinders, pneumatic systems, conveyor roller tubes requiring tight OD tolerance |
| Shipbuilding & Marine | Ballast lines, fire-main piping, deck structural rounds per marine classification standards |
What Weld Seam Quality Costs You on an ERW Round Pipe Order
A poorly controlled ERW weld seam turns a routine pipe delivery into a jobsite re-cutting disaster.
I once watched a crew in the Philippines pull 6-meter ERW round pipes from a container, only to find the internal weld bead had not been ground flush. Fit-up on the structural connections was impossible without re-cutting every single piece. That batch looked fine on paper — the mill test certificate was in order, the dimensions were within tolerance — but the weld seam told a different story once it hit the field. [NEED_CITE: ERW weld seam quality requirements per ASTM A53 and API 5L]
Global buyers sourcing carbon steel ERW round pipes regularly encounter three compounding problems: inconsistent weld integrity across heats, wall thickness that drifts toward the negative tolerance limit, and documentation that does not match the material actually loaded. When the weld seam is not inspected in-process, dimensional tolerance degrades at the weld zone, and the pipe fails to hold roundness during cutting and welding on site.
How ERW Round Pipe Specs Match Structural and Pipeline Applications
A Carbon Steel ERW Round Pipe in Q235B or S235JR serves load-bearing structural frames where moderate strength and good weldability are required, while stepping up to Q345B or S355J2 handles heavier spans and dynamic loads in scaffolding and industrial frameworks. For oil and gas transmission, API 5L grades from Gr.B through X70 provide the pressure-rated performance that gathering lines and distribution networks demand. The OD range of 14–1200 mm and wall thickness up to 50 mm means a single supplier can cover everything from small-bore instrumentation lines to large-diameter structural columns, reducing the coordination burden that comes with fragmented sourcing across multiple mills.
Engineering Compliance and Surface Protection Selection
Structural applications governed by EN 1993 or AISC specifications require documented yield strength and traceable heat numbers — the Carbon Steel ERW Round Pipe supplied under EN 10217-1 or ASTM A53 carries the necessary certification framework for European and North American project acceptance. [NEED_CITE: EN 10219 cold-formed welded structural hollow section compliance] Corrosion environment dictates surface treatment: black painted or oiled finishes suit indoor structural use, hot-dip galvanized protects outdoor scaffolding and coastal installations, and 3LPE or 3LPP coating extends service life for buried pipeline segments in aggressive soil conditions. Wall thickness tolerance of ±1% ensures that theoretical weight calculations remain reliable for structural load analysis, while beveled or threaded ends allow direct field welding or mechanical coupling without secondary machining. [NEED_CITE: steel grade equivalence mapping between GB, EN, and ASTM systems]
Understanding Grade Selection and ERW Process Fundamentals
The Carbon Steel ERW Round Pipe portfolio spans three major grading systems. The Chinese Q-series (Q235, Q345) offers cost-effective general structural performance, with Q345 delivering higher yield strength for heavier frames. The European S-series (S235JR, S275JR, S355J2) provides guaranteed impact toughness at sub-zero temperatures — the JR designation covers +20°C impact testing, while J2 extends to −20°C, a critical distinction for projects in northern climates. The ASTM and API grades (A53, A106, API 5L Gr.B through X70) serve pressure-containing applications where tensile and yield properties must meet specific minimums for fluid and gas transmission.
The ERW process forms the round profile from coiled steel strip through continuous forming and high-frequency electric resistance welding, producing a longitudinal weld seam. Compared to seamless pipe, ERW offers tighter dimensional tolerance and lower cost at moderate diameters; compared to SSAW, ERW delivers a straighter seam with more consistent weld quality at smaller diameters. The in-house physical and chemical laboratory tests every heat for chemical composition, tensile properties, and weld seam integrity before the pipe leaves the mill.
Surface treatment selection follows the service environment: hot-dip galvanizing provides sacrificial zinc protection for outdoor and humid conditions, while 3LPE coating combines epoxy adhesion with polyethylene mechanical protection for buried or submerged pipeline segments. Black painted or varnished finishes serve as temporary corrosion protection during transit and indoor storage.
The Hidden Cost of Buying ERW Round Pipe Without Verified Documentation
Ordering a Carbon Steel ERW Round Pipe based on price alone, without confirmed mill test certificates and third-party inspection, introduces risks that surface only after the material reaches the jobsite. A steel grade substitution — Q235 shipped where S355JR was specified — will not be caught by visual inspection but will fail structural load testing during project acceptance. Missing or mismatched EN 10204 3.1 certificates trigger customs holds in the EU, delaying the entire project timeline. [NEED_CITE: EN 10204 inspection document types for steel products] Wall thickness that consistently drifts to the negative tolerance boundary reduces load-bearing capacity and may violate the structural engineer’s design assumptions, forcing costly reinforcement or complete pipe replacement in the field.
Why Procurement Teams Source Carbon Steel ERW Round Pipe Through Xin Jiyuan
Every Carbon Steel ERW Round Pipe order is produced on dedicated ERW lines with in-process weld seam inspection and final dimensional checks conducted by our in-house physical and chemical laboratory — no outsourced testing, no certificate gaps. Our facility holds 41 invention patents and covers over 2,800 specifications across six product categories, meaning structural rounds, pipeline grades, and machined ends can be consolidated under a single purchase order rather than split across three suppliers. CE certification under EN 10210 and EN 10219 clears European customs without supplementary documentation, while ISO 9001:2015 registration ensures repeatable quality across production heats. Non-standard outer diameters, custom wall thicknesses, and cut-to-length requirements are handled in-house, avoiding the extended lead times that come from routing custom orders through trading intermediaries. Professional container loading plans optimize weight distribution for heavy pipe cargo, and our logistics team coordinates FOB, CIF, and DDP shipments to over 50 countries with real-time tracking from mill gate to project site.
Documentation & Compliance
- Mill test certificate documenting Q235B/Q345B chemical composition and mechanical properties per GB/T 6728, with heat number traceability
- EN 10204 3.1/3.2 inspection certificate for S235JR/S355J2 grades supplied under EN 10217-1, confirming yield strength and impact test results
- CE certificate under EN 10210/EN 10219 for structural hollow sections destined for European Union member states
- SGS or BV third-party inspection report covering dimensional verification, weld seam quality, and surface treatment thickness before container loading
- Material traceability report linking each pipe bundle to its original heat number, steel grade, and production date
- Full customs documentation package including packing list, bill of lading, and certificate of origin for import clearance in destination country
Packaging, Loading & Delivery
- API 5L and ASTM A53 ERW round pipes bundled with steel strip ties and seaworthy wrapping, with end protectors on beveled or threaded finishes to prevent thread damage during ocean transit
- Hot-dip galvanized Carbon Steel ERW Round Pipe bundles separated by rubber垫层 to preserve the zinc coating and prevent surface scratching during handling and shipping
- Container loading plans optimized for 6 m and 12 m fixed lengths, with nested smaller-diameter pipes inside larger OD tubes to maximize weight per 20ft or 40ft container
- Custom cut-to-length pipes bundled separately by size and heat number, with clear markings showing steel grade, OD, wall thickness, and length on each bundle
- Heat number and steel grade stenciled on each pipe end for field identification, matching the mill test certificate and packing list
- FOB, CIF, and DDP shipping terms available with door-to-door logistics coordination to ports and project sites across Southeast Asia, the Middle East, Europe, and the Americas
Start Your Carbon Steel ERW Round Pipe Inquiry
Submit your specification sheet — including steel grade, outer diameter, wall thickness, length, surface treatment, and destination port — to receive a detailed quotation with production lead time, applicable certifications, and container loading plan. Non-standard dimensions and custom end treatments are quoted separately with confirmed feasibility.
Request a Quotation with Mill Test Certificate
Send your specifications via email to admin@sdxjysteel.com or contact us on WhatsApp at +86 188 5315 7756 to receive pricing, certification documents, and delivery confirmation for your Carbon Steel ERW Round Pipe order.
Frequently Asked Questions
Q: How do Q235/Q345 Chinese grades map to S235JR/S355J2 European and A53/A36 American grades?
A: Q235B is broadly equivalent to S235JR and ASTM A36 in yield strength range, while Q345B corresponds to S355JR and ASTM A572 Gr.50. For precise project compliance, we provide cross-reference documentation and can supply material tested to multiple standards simultaneously upon request.
Q: Can you provide EN 10204 3.1/3.2 mill test certificates and arrange third-party SGS or BV inspection?
A: Yes. Every shipment includes an original EN 10204 3.1 mill test certificate documenting chemical composition and mechanical properties by heat number. Third-party inspection by SGS or BV can be arranged before container loading at the buyer’s request, with the inspection report included in the shipping documentation package.
Q: What is the minimum order quantity for non-standard outer diameters or cut-to-length pipes?
A: MOQ depends on the specific diameter, wall thickness, and steel grade requested. Standard sizes in Q235B, Q345B, and common ASTM/EN grades typically have flexible MOQ, while non-standard dimensions or less common grades such as API 5L X60/X70 may require higher minimum tonnage. Submit your specification for a confirmed MOQ and lead time.
Q: When should I specify hot-dip galvanized versus 3LPE coating versus black painted surface treatment?
A: Hot-dip galvanizing is the standard choice for outdoor structural applications and coastal environments where sacrificial zinc protection is needed. 3LPE or 3LPP coating is specified for buried pipeline segments exposed to aggressive soil chemistry or submerged conditions. Black painted or oiled finishes provide temporary corrosion protection for indoor structural use or pipes that will receive field-applied coating after installation.
Q: Do you offer FOB, CIF, and DDP terms, and how do you optimize container loading for heavy pipe cargo?
A: We offer FOB, CIF, and DDP shipping terms based on your preference. Container loading is planned by our logistics team to maximize weight utilization — smaller-diameter pipes are nested inside larger OD tubes, and bundle weights are distributed to meet road transport limits at destination. Real-time tracking is provided from mill departure through port discharge.
