Description
Factory-Direct ERW Pipe Supply — Full-range Q235 Q345 A36 ERW welded round steel pipe produced on dedicated lines with in-house lab testing, shipped directly to your project site without trading markups.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | Q235 Q345 A36 ERW Welded Round Steel Pipe |
| Product Type | ERW Welded Round Steel Pipe |
| Steel Grade | Q235, Q345 (Q355), A36, S355, 20#, 45#, 16Mn, Q195 |
| Standard | API 5L, ASTM A53, ASTM A106, ASTM A252, ASTM A500, ASTM A671, ASTM A450, ASME B36.10M, BS EN 10219, BS EN 10296, BS 1387, BS 6323, BS 6363, GB/T 3091, GB/T 13793, GB/T 9711, JIS G3466 |
| Section Shape | Round |
| Size Range | OD 6–1820 mm |
| Wall Thickness | Cold rolled 1–4.0 mm; Hot rolled 4–20 mm |
| Length | 1–12 m (standard 6 m / 12 m) |
| Technique | ERW (Electric Resistance Welded), Hot Rolled / Cold Rolled / Cold Drawn |
| Surface Treatment | Hot Rolled, Oiled / Non-oiled (Slightly Oiled) |
| Tolerance | ±1% |
| Ends | Plain / Beveled (available upon request) |
| Application | Fluid transport, boiler systems, hydraulic pipelines, structural applications, scaffolding, machinery manufacturing |
| MOQ | 5 Tons |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| EPC Contractors | Fluid and gas transmission pipelines, industrial boiler feed lines, chemical fertilizer conveyance systems |
| Construction Companies | Structural columns and beams for high-rise frames, scaffolding uprights, bridge support piling |
| Machinery Manufacturers | Hydraulic cylinder barrels, precision equipment frames, conveyor roller shafts |
| Infrastructure Developers | Water supply networks, drainage culverts, underground utility conduits |
What Wall-Thickness Tolerance Costs on a Q235 Q345 A36 ERW Welded Round Steel Pipe Order
Negative tolerance abuse turns theoretical weight savings into structural liability.
Running rigging calipers across a container of ERW pipe at a Riyadh site taught me the hard way what happens when wall thickness slips beyond ±1%. The SGS inspector was measuring every third length, and whole bundles failed the EN 10219 minimum threshold. Project engineers don’t argue about price after that — they argue about who pays for the re-shipment. [NEED_CITE: EN 10219 cold-formed welded structural hollow section dimensional tolerances]
When you source a Q235 Q345 A36 ERW welded round steel pipe, the tolerance spec in your purchase contract must match the mill’s actual production capability — not the brochure promise. Missing certification compounds the problem: customs holds, rejected inspection reports, and delayed crane schedules all trace back to a single decimal point on a wall-thickness reading.
Matching OD and Wall Thickness to Structural Load Paths
Every Q235 Q345 A36 ERW welded round steel pipe we roll goes through a load-path review before it leaves the mill floor. For OD 32–219 mm scaffolding uprights, cold-rolled wall thickness between 1–4.0 mm keeps weight manageable while meeting EN 10219 buckling requirements. When the same pipe moves into hydraulic cylinder applications at OD 200–600 mm, hot-rolled walls of 4–20 mm handle internal pressure cycles that cold-formed sections cannot sustain. The ±1% tolerance holds across both ranges because our in-house lab checks every heat before bundling.
Engineering Compliance Across Destination Markets
Structural frames destined for EU sites must carry CE marking under EN 10210 or EN 10219 — without it, the pipe sits at the port while your crane idles. North American projects specify ASTM A53 or A500, and the mill test certificate needs to show chemical composition and yield strength against those exact clauses. We produce Q235 Q345 A36 ERW welded round steel pipe to all three standard families from the same line, switching grade chemistry and rolling parameters per order. Beveled ends cut to ASME B36.10M angles arrive ready for site welding, eliminating secondary machining at the laydown yard. [NEED_CITE: ASTM A53 and EN 10219 dimensional and mechanical requirement comparison]
Steel Grade Selection and ERW Process Fundamentals
Q235 and A36 occupy the same yield-strength tier — roughly 235 MPa minimum — making them interchangeable for general structural frames where extreme loading is absent. Step up to Q345 (Q355) or S355 and you gain roughly 50% more yield capacity, which matters when column spacing widens or seismic categories tighten. The ERW process fuses the longitudinal seam through electrical resistance heating without filler metal, producing a weld zone that matches base-metal strength when rolling and annealing parameters hold steady. For fluid transport under pressure, hot-rolled ERW pipe in grades 20# or 16Mn provides the ductility needed to withstand internal surge cycles. Surface treatment stays simple — oiled for short-term transit protection or bare hot-rolled for projects that apply their own coating system on site.
Hidden Costs of Specifying the Wrong Grade or Skipping Mill Verification
Ordering Q235 when the structural engineer specified S355 means the pipe yields before the frame reaches design load — a failure that only surfaces during load testing or, worse, under service conditions. Skipping the mill test certificate to save a few days on paperwork means you cannot prove heat-to-heat traceability when the inspector asks for it. Negative tolerance beyond the ±1% we guarantee means you paid for steel thickness that isn’t there, and replacement costs fall on whoever signed the purchase order. [NEED_CITE: consequences of steel grade mismatch in structural engineering projects]
Why Project Procurement Teams Source Q235 Q345 A36 ERW Welded Round Steel Pipe From Us
We run three dedicated ERW lines covering OD 6–1820 mm, which means your 219 mm × 8 mm scaffolding tube and your 820 mm × 16 mm piling pipe roll from the same facility under one quality system. Every heat passes through our physical and chemical laboratory before bundling — no outsourcing the tensile tests. Our 41 invention patents include proprietary sharp-corner rectangular tube technology, but for round ERW pipe the advantage is simpler: consistent weld-seam integrity across the full OD range. CE EN 10210/10219, Lloyd’s Register, ISO 9001:2015, and SGS/BV third-party inspection reports ship with every container. We have exported to 50+ countries since 2013, and our loading plans optimize container fill for mixed-diameter orders so you don’t pay to ship air.
Documentation & Compliance
- Mill Test Certificate documenting Q235/Q345/A36 chemical composition and mechanical properties per GB/T 9711, ASTM A53, or EN 10219 as specified
- CE certificate covering EN 10210/EN 10219 compliance for structural hollow sections entering EU markets
- ISO 9001:2015 quality management certificate covering the full ERW production and inspection chain
- SGS or BV third-party inspection report verifying wall thickness, OD, and weld-seam quality before container sealing
- Heat-number traceability linking every bundled length to its original slab chemistry and rolling record
- Customs documentation package including packing list, bill of lading, and certificate of origin for destination-port clearance
Packaging, Loading & Delivery
- ERW round pipe bundled with galvanized steel strips at intervals matched to the 6 m or 12 m standard length, preventing bundle shift during ocean transit
- Oiled surface treatment applied before bundling to prevent flash rust on hot-rolled Q235 and Q345 grades during humid-weather shipping
- Container loading plans optimized for mixed-OD orders — small-diameter pipe nested inside larger sections to maximize TEU fill and reduce freight cost per ton
- Custom cut-to-length service available for 1–12 m requirements, with cut ends deburred and marked by heat number and steel grade
- Each bundle tagged with weatherproof labels showing OD, wall thickness, steel grade, heat number, and standard designation
- FOB, CIF, and DDP logistics options with real-time tracking from Jinan port to project site across 50+ destination countries
Getting Your Q235 Q345 A36 ERW Welded Round Steel Pipe Quote Moving
Send your specification sheet — OD, wall thickness, length, steel grade, quantity, and destination port — and we return a detailed quotation within 12 hours including unit price, production lead time, applicable certifications, and payment terms. If your project requires non-standard dimensions or special end treatment, we confirm feasibility and tooling requirements before you commit.
Frequently Asked Questions
Q: Can Q235, Q345, and A36 grades be used interchangeably on the same project?
A: Q235 and A36 share similar yield strength levels and are often interchangeable for general structural use. Q345 offers higher yield capacity and should be used where the structural engineer specifies it. We produce all three grades on the same ERW line and provide separate mill test certificates for each heat.
Q: What third-party inspection options are available before shipment?
A: SGS and BV inspection teams can attend our facility to verify wall thickness, outer diameter, weld-seam quality, and surface condition before containers are sealed. Inspection reports are included in the shipping documentation package.
Q: Do you supply non-standard OD or wall thickness outside the catalog range?
A: Yes. Beyond the standard 6–1820 mm OD and 1–20 mm wall thickness range, we produce custom non-standard sizes on request. MOQ for special orders depends on the specification and is confirmed during the quotation stage.
Q: Which surface treatment is best for long-term outdoor exposure?
A: The standard oiled finish protects against transit corrosion. For outdoor structural or fluid applications, we can supply galvanized coating or coordinate 3PE anti-corrosion coating applied after ERW forming, depending on your project specification.
Q: How do you handle mixed-size orders for a single container?
A: Our loading team prepares a container optimization plan that nests smaller-OD pipe inside larger sections, maximizing weight per TEU and reducing your freight cost per ton. The plan is shared with you for approval before loading begins.
Get Your Q235 Q345 A36 ERW Welded Round Steel Pipe Quote Today
Submit your specifications — OD, wall thickness, grade, quantity, and destination — to receive a detailed quotation with mill test certificate options within 12 hours.
Shandong Xin Jiyuan Special Steel Tube Co., Ltd
Website: www.sdxjysteel.com
Tel: +86 531 8573 6315
Mobile/WhatsApp/WeChat: +86 188 5315 7756
Email: admin@sdxjysteel.com
Address: No.11889, Jingshi West Road, Lulian Group, Jinan City, Shandong Province, China
