Description
Factory-Direct ERW Pipe Supply — Q235 and Q345 welded round steel pipes rolled and dispatched from our own Jinan facility with original mill test certificates for every heat.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | Q235 Q345 ERW Welded Round Steel Pipe |
| Product Type | ERW Welded Steel Pipe / Spiral Welded Pipe (SSAW) |
| Steel Grade | Q195, Q235, Q345, S235JR, S275JR, S355JR, SS400, A36, A572 |
| Standard | JIS, CE, ISO 9001 |
| Section Shape | Round |
| Size Range | OD 10 – 2000 mm (spiral up to 3520 mm) |
| Wall Thickness | 5 – 30 mm |
| Length | 1 – 12 m (standard 6 m / 9 m / 12 m, cut-to-length available) |
| Technique | ERW / Spiral Welded (SSAW) |
| Surface Treatment | Black Painted / Cold Rolled / Non-oiled |
| Tolerance | ±1% |
| Ends | Plain / Beveled |
| Application | Fluid transport, boiler, construction structure, bridge piling |
| MOQ | 10 Tons |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Infrastructure & Bridge Construction | Bridge piling, foundation casings, pile sleeves for highway and rail projects |
| Oil, Gas & Water Utilities | Low-pressure fluid transport pipelines, water mains, drainage conduits |
| General Construction | Structural columns, scaffolding uprights, industrial building frames |
| Petrochemical & Fertilizer Plants | Chemical fertilizer feed lines, process water piping, utility racks |
| Marine & Port Engineering | Jetty piling, mooring fender supports, dock foundation tubes |
When Grade Equivalence Between GB, EN and ASTM Causes Procurement Delays
Mis-matched steel grade standards are the single most common reason welded pipe orders get held at customs or rejected at site inspection.
Buyers specifying Q235 for a project often receive enquiries back asking whether S235JR or A36 is acceptable — and without a clear equivalence statement from the supplier, the procurement team either pauses the order or guesses wrong. On an ERW welded round steel pipe order destined for West Africa or Southeast Asia, this confusion can add weeks to lead time and trigger re-inspection costs at the port. [NEED_CITE: steel grade equivalence between GB, EN and ASTM standards]
Beyond grade confusion, missing or inconsistent mill test certificates create a second bottleneck. When heat numbers on the pipe do not match the MTC, or when chemical composition data is absent, third-party inspectors flag the shipment — and the buyer bears the cost of re-testing or return.
Matching Pipe Diameter and Wall Thickness to Piling and Fluid Transport Loads
Spiral welded sections in Q345 up to OD 3520 mm serve bridge piling and jetty foundation work where large-diameter casings must withstand driving impact and lateral soil pressure. For fluid transport at lower pressures, ERW welded round steel pipe in Q235 or S235JR from OD 10 mm upward covers water mains, drainage and process utility lines. Wall thickness from 5 mm to 30 mm with ±1% tolerance ensures the pipe meets design load assumptions without hidden negative-tolerance shortfalls that would reduce actual section modulus on site.
Structural Compliance and Surface Protection for Site Conditions
Engineering specifications for structural frames and piling typically reference EN 1993 or AISC design codes, which require documented yield strength and traceable heat numbers. [NEED_CITE: EN 10219 cold-formed and welded hollow section structural requirements] For outdoor piling or marine environments, black painted or oiled surface treatment provides short-term transit protection, while long-term corrosion resistance depends on design-specified coating applied after installation. CE certification and ISO 9001 production traceability satisfy EU and international customs documentation requirements, reducing the risk of port holds. Cut-to-length service at 6 m, 9 m or 12 m — or custom lengths — minimizes on-site cutting waste and welding joints.
Steel Grade Selection and Welding Process Fundamentals
The Q-series (Q195, Q235, Q345) follows the Chinese GB standard system where the number indicates minimum yield strength in MPa; Q345 offers higher load-bearing capacity than Q235 for structural and piling applications. The S-series (S235JR, S275JR, S355JR) follows EN standards and is specified for European-market projects requiring CE marking. ASTM A36 and A572 serve North American and international projects referencing US standards. ERW welding produces a longitudinal seam suitable for small to medium diameters up to 2000 mm at lower cost, while spiral submerged arc welding (SSAW) covers diameters up to 3520 mm for large-diameter piling and water transmission where seam orientation distributes stress more evenly under external loading. [NEED_CITE: ERW vs SSAW welded pipe application differences]
Surface treatment choice — black painted, cold rolled or non-oiled — depends on storage duration and end-use environment. Black painted finish protects during transit and short-term outdoor storage; non-oiled surfaces suit pipes that will receive field-applied coatings such as 3PE or epoxy before installation.
Hidden Costs of Unverified Tolerance and Missing Documentation
Pipes supplied with uncontrolled negative tolerance may pass visual inspection but fail dimensional checks during third-party survey, triggering re-measurement fees or partial rejection. [NEED_CITE: negative tolerance impact on structural steel acceptance] More critically, pipes without traceable heat numbers or with MTC data that does not match the physical shipment cannot be certified for structural use — meaning the entire batch may be downgraded to non-structural applications or scrapped, with the buyer absorbing material and delay costs.
Why Project Procurement Teams Source ERW Welded Round Steel Pipe Through Us
Our Jinan mill facility rolls Q235, Q345 and equivalent EN/ASTM grades in-house, eliminating trader mark-ups and enabling direct mill test certificate issuance per heat. Every ERW welded round steel pipe order ships with original MTC documenting chemical composition and mechanical properties, verified by our internal laboratory before dispatch. For projects requiring independent validation, we arrange SGS or BV third-party inspection at the mill prior to loading. Custom cut-to-length, beveled ends and surface treatment are processed in our own facility rather than outsourced, maintaining dimensional control and traceability through each step. Professional heavy-cargo loading — using flatbed, open-top container or break-bulk methods — is planned by our own logistics team with direct experience in West African and Southeast Asian port discharge requirements.
Documentation & Compliance
- Mill test certificate documenting Q235 or Q345 chemical composition, yield strength and tensile properties per heat number, issued before or with shipment
- CE certificate confirming conformity with EN welded pipe standards for EU market customs clearance
- ISO 9001:2015 quality management certificate covering the full production and inspection process
- SGS or BV third-party inspection report available for dimensional verification, weld seam examination and coating thickness measurement
- Full material traceability from heat number through rolling, welding, inspection and dispatch
- Export customs documents including packing list, bill of lading and certificate of origin prepared per destination country requirements
Packaging, Loading & Delivery
- Black painted ERW welded round steel pipe bundled with steel strips and edge protectors to prevent coating damage during ocean transit
- Spiral welded large-diameter pipe loaded on flatbed or open-top container with timber cradles and chocking to prevent rolling and ovality deformation
- Cut-to-length service at 6 m, 9 m or 12 m standard lengths or custom sizes, nested to optimize container payload within axle and port weight limits
- Heat number and steel grade stenciled on each pipe end for on-site identification and MTC cross-referencing during inspection
- FOB, CIF and DDP shipping terms available with full export documentation and tracking through to destination port or site
- Break-bulk and project cargo loading for spiral pipe exceeding container dimensions, with lashing and bracing plans approved by carrier prior to dispatch
Requesting a Quotation for Your ERW Welded Round Steel Pipe Order
Submit your required steel grade, outer diameter, wall thickness, length, quantity and destination port to receive a detailed quotation including material cost, any cutting or end-finishing charges, and shipping terms. We respond to technical enquiries within 12 hours and provide the mill test certificate for your review before shipment is finalized.
Start Your ERW Welded Round Steel Pipe Enquiry
Send your specification and destination to receive pricing, mill test certificate preview and loading plan within one working day.
Shandong Xin Jiyuan Special Steel Tube Co., Ltd
Website: www.xjyplate.com
Tel: +86 531 8573 6315
Mobile/WhatsApp/WeChat: +86 188 5315 7756
Email: admin@xjyplate.com
Address: No.11889, Jingshi West Road, Lulian Group, Jinan City, Shandong Province, China
Frequently Asked Questions
Q: How do Q235 and Q345 compare to S235JR and S355JR for international projects?
A: Q235 and S235JR share similar yield strength levels and are generally interchangeable for structural applications; Q345 and S355JR both offer higher yield strength for heavier load-bearing requirements. We provide grade equivalence guidance and issue MTC per the standard your project specifies, so customs and site inspectors accept the documentation without additional testing.
Q: Can you supply mill test certificates and arrange third-party inspection before shipment?
A: Yes. Original mill test certificates documenting chemical composition and mechanical properties per heat number are provided before or with every shipment. SGS and BV third-party inspection can be arranged at our mill for dimensional checks, weld seam verification and coating measurement.
Q: What is the minimum order quantity and can you cut to custom lengths?
A: The minimum order quantity is 10 tons. We offer standard lengths of 6 m, 9 m and 12 m, and can cut to exact project-specified lengths to reduce on-site waste and welding joints.
Q: How do you handle shipping for large-diameter spiral welded pipe that exceeds container size?
A: For spiral pipe with OD above standard container limits, we use flatbed truck, open-top container or break-bulk vessel loading with timber cradles, chocking and lashing plans approved by the carrier. FOB, CIF and DDP terms are all available with full export documentation.
Q: What surface treatment options are available for different service environments?
A: We supply black painted, cold rolled and non-oiled finishes. Black painted suits transit protection and short-term outdoor storage; non-oiled surfaces are specified when the pipe will receive field-applied coatings such as epoxy or 3PE before installation.
