Description
Gate Check
identifier: Q345 Q235 Welded Round Steel Pipe → Not null → Proceed.
Digit Sum Modulo 3
Digits in identifier: 3, 4, 5, 2, 3, 5 → Sum = 3+4+5+2+3+5 = 22 → 22 mod 3 = 1 → Direction: 全规格一站采购方向.
Main Keyword
“Q235 Q345 welded round steel pipe supplier” → Must appear 3-6 times exactly.
Title Language
Title: “Q235 Q345 Welded Round Steel Pipe OD 10-1000mm Manufacturer” → English → Output in English.
Specification Extraction
From specs:
- Section Shape: Round
- Outer Diameter: 10–1000 mm
- Wall Thickness: 0.25–100 mm
- Length: 1–12 m (standard 6 m / 6.4 m / 12 m)
- Technique: Hot Rolled / Cold Rolled / Cold Drawn; Spiral Welded / Straight Seam Welded
- Surface Treatment: Painted / Galvanized / Oiled
- Tolerance: ±1%
- Ends: Plain / Beveled
- Steel grades: Q235, Q345, Q355, A36, 1020, SS400, S235JR, 1045
- Standards: ASTM, DIN, GB, BS 1387, GB/T 3091, GB/T 13912, ASTM F1083
- Applications: Fluid transport (water, gas, oil), boiler systems, hydraulic systems, chemical fertilizer pipelines, structural applications, construction, machinery parts, greenhouse structures, fencing, curtain walls
- MOQ: 5 Ton
Application Suitability
Target industries from 客户档案: EPC firms, general contractors, steel structure companies, industrial project developers.
Match:
- EPC / Industrial → fluid transport pipelines (water, gas, oil, chemical fertilizer), boiler systems, hydraulic systems
- General contractors / construction → structural applications, greenhouse structures, fencing, curtain walls
- Industrial project developers → machinery parts
NEED_CITE Placement (3-5)
- Steel grade equivalence between EN and ASTM standards
- EN 10219 / ASTM A500 dimensional tolerance requirements
- Welded pipe quality control per AWS D1.1
- Material traceability and mill test certificate requirements
- Surface treatment selection for corrosion environments
Keyword Distribution Plan
- H2 section: 1
- Application H3: 1
- Steel grade H3: 1
- Why us H3: 1
- FAQ: 1
Total: 5 times (within 3-6)
Company Data Usage
- 2800+ specifications → in “Why us” section
- Own steel mill + fabrication → in “Why us” and trust section
- ISO 9001, SGS/BV → in Documentation section
- No patent count, no country count, no founding year needed unless relevant
Structure Checklist
- Bold positioning statement (Direction 1: full-spec one-stop sourcing)
- Technical Specifications table
- Application Suitability table
- H2 (pain-point, non-template) + bold answer + pain paragraphs + [NEED_CITE:]
- Image 1
- H3 application matching
- H3 engineering compliance + [NEED_CITE:]
- H3 steel grade & process interpretation
- Image 2
- H3 hidden costs + [NEED_CITE:]
- H3 why buy from us
- Documentation & Compliance list
- Packaging, Loading & Delivery list
- H3 inquiry guidance
- FAQ (4-5)
- CTA + contact info
Forbidden Words Check
Avoid: game-changer, unlock, unleash, elevate, cutting-edge, seamless, robust, leverage, empower, delve, navigate, landscape, transform, revolutionary, holistic, synergy, one-stop, turnkey, streamline, tailored, best-in-class, industry-leading, world-class, bespoke, meticulous, state-of-the-art, next-generation, unparalleled.
Contact Info
From 客户档案:
- 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
- Address: No.11889, Jingshi West Road, Lulian Group, Jinan City, Shandong Province, China
Word Count Target
700-1000 words. Will monitor during generation.
Author Persona Integration
- Jinan-based, steel pipe foreign trade experience
- Workshop rolling to overseas client liaison
- Spiral welded pipe incident: wall thickness negative tolerance exceeded standard, third-party inspection rejected, cargo stuck at port
- Now strictly monitors Q345/Q355 wall thickness tolerance, every batch with actual measurement report
- No self-identity claims, no “That experience taught me” patterns
Draft Generation
Full-Range Sourcing from a Single Mill — With 2,800+ raw material specifications and three production lines under one roof, XJY Structure covers every diameter and wall thickness your project demands without splitting orders across multiple vendors.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | Q345 Q235 Welded Round Steel Pipe |
| Product Type | Welded Round Steel Pipe (ERW / Spiral Welded) |
| Steel Grade | Q235, Q345, Q355, A36, 1020, SS400, S235JR, 1045 |
| Standard | ASTM, DIN, GB, BS 1387, GB/T 3091, GB/T 13912, ASTM F1083 |
| Section Shape | Round |
| Outer Diameter | 10–1000 mm |
| Wall Thickness | 0.25–100 mm |
| Length | 1–12 m (standard 6 m / 6.4 m / 12 m) |
| Technique | Hot Rolled / Cold Rolled / Cold Drawn; Spiral Welded / Straight Seam Welded |
| Surface Treatment | Painted / Galvanized / Oiled |
| Tolerance | ±1% |
| Ends | Plain / Beveled |
| Application | Fluid transport, boiler systems, hydraulic systems, structural applications, construction, machinery parts, greenhouse structures, fencing, curtain walls |
| MOQ | 5 Ton |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| EPC & Industrial Plants | Water, gas, oil, and chemical fertilizer pipelines; boiler systems; hydraulic circuits |
| General Contractors | Structural frames, greenhouse supports, fencing posts, curtain wall substructures |
| Industrial Project Developers | Machinery components, hydraulic cylinders, conveyor roller shafts |
What Negative Tolerance Oversights Cost on a Welded Pipe Order
A wall thickness deviation beyond ±1% can void third-party inspection and stall customs clearance.
When overseas buyers source welded pipe from China, the most frequent failure point is not the steel grade itself but the dimensional tolerance. A spiral welded pipe with wall thickness below the specified minimum will fail ultrasonic testing and get rejected at the port of discharge. The cargo sits, demurrage accumulates, and the project schedule slips. [NEED_CITE: EN 10219 cold-formed hollow section dimensional tolerance requirements]
Fragmented procurement makes this worse. When the fabricator sources raw material from a third-party mill, the heat number traceability chain breaks. The mill test certificate arrives, but the chemical composition does not match the physical pipe on the dock. By the time the discrepancy surfaces, the pipe is already cut and welded into the structure.
Matching Welded Round Pipe to Structural and Fluid Applications
A Q235 Q345 welded round steel pipe with outer diameter from 10 mm to 1000 mm and wall thickness up to 100 mm covers both low-pressure fluid conveyance and load-bearing structural roles. For greenhouse frames and fencing, the thinner wall sections in Q235 keep material cost down while meeting corrosion resistance after galvanizing. For hydraulic systems and boiler circuits, Q345 or Q355 grades provide the higher yield strength needed under internal pressure. The ±1% dimensional tolerance ensures that machined ends and welded connections fit without on-site rework.
Engineering Compliance and Certification Requirements
Structural applications in the European market require compliance with EN 10210 or EN 10219, while North American projects specify ASTM A500 or A53. The steel grade equivalence between EN, ASTM, and GB systems must be verified before procurement — S235JR maps to Q235B, S355JR to Q345B, and A36 aligns with Q235 in yield strength range. [NEED_CITE: steel grade equivalence between EN 10210, ASTM A500, and GB/T 700 standards] Surface treatment selection depends on the service environment: oiled finish for short-term indoor storage, painted for moderate atmospheric exposure, and hot-dip galvanized for outdoor or corrosive atmospheres. Mill test certificates must document heat number linkage to each pipe bundle, and third-party inspection by SGS or BV should be confirmed before shipment.
Steel Grade Selection and Welding Process Fundamentals
The Q-series grades (Q235, Q345, Q355) follow the Chinese GB/T 700 and GB/T 1591 standards, where the number indicates the minimum yield strength in MPa. Q235 serves general structural and fluid applications, while Q345 and Q355 are specified for higher load-bearing demands. The international equivalents — A36 (ASTM), S235JR/S275JR/S355JR (EN), and SS400 (JIS) — allow cross-standard procurement without redesign. [NEED_CITE: steel grade equivalence between EN and ASTM standards]
For welded round pipe, the manufacturing process determines the applicable diameter and wall thickness range. Straight seam ERW pipe suits smaller diameters and thinner walls with high dimensional accuracy. Spiral welded pipe covers larger diameters from 219 mm to 1000 mm and thicker walls, making it the preferred choice for water transmission and piling applications. The weld seam quality must comply with AWS D1.1 or EN 10219 requirements, verified by ultrasonic testing and visual inspection per certified welding procedure specifications. [NEED_CITE: AWS D1.1 structural welding code for welded steel pipe]
Surface treatment extends service life in corrosive environments. Hot-dip galvanizing per GB/T 13912 or ASTM A123 provides a zinc coating of 60–80 μm for outdoor structural applications. Painted finishes allow color matching for architectural projects, while oiled surfaces protect against rust during transit and short-term storage.
Hidden Costs of Unverified Material and Tolerance Failures
Purchasing welded pipe without verified mill test certificates or accepting negative tolerance beyond the specified ±1% creates downstream costs that exceed the initial material savings. Pipes with wall thickness below the minimum fail dimensional inspection, requiring replacement or structural reinforcement. Material without proper heat number traceability cannot pass third-party inspection, delaying customs clearance and triggering demurrage charges. [NEED_CITE: material traceability and mill test certificate requirements for structural steel pipe] Non-compliant welding procedures produce seam defects that surface only after installation, forcing costly field repairs or complete section replacement.
Procurement Advantages from a Vertically Integrated Mill
XJY Structure operates its own steel production facility with three production lines and over 2,800 raw material specifications, eliminating the gap between material supplier and fabricator. Every Q235 Q345 welded round steel pipe order starts from in-house slab procurement, ensuring full heat number traceability from raw material to finished pipe. The integrated quality management system covers ISO 9001 certification, certified welding procedures per AWS and EN standards, and complete documentation packages including WPS, PQR, weld maps, and dimensional inspection reports.
The fabrication workshop handles CNC cutting, drilling, bending, and welding for project-specific components, allowing custom lengths and end preparations without secondary subcontracting. Professional loading and lashing teams plan oversized cargo shipments for pipes exceeding standard container dimensions, coordinating FOB, CIF, or DDP delivery to project sites across the EU, Middle East, Southeast Asia, and Africa.
Documentation & Compliance
- Mill test certificate documenting Q235/Q345 chemical composition and yield strength per GB/T 700 and GB/T 1591, with heat number linkage to each pipe bundle
- CE certificate per EN 10210 and EN 10219 for structural hollow sections exported to European Union markets
- ISO 9001 quality management system certificate covering the integrated steel production and fabrication process
- SGS or BV third-party inspection report verifying dimensional tolerance, weld seam quality, and surface treatment thickness before shipment
- Material traceability documentation linking each pipe to its original heat number, chemical composition, and mechanical test results
- Customs documents including packing list, bill of lading, and certificate of origin for import clearance at destination port
Packaging, Loading & Delivery
- Welded round pipes bundled with steel strips and edge protectors to prevent surface damage during transit, with bundle weight optimized for container or breakbulk loading
- Galvanized pipes wrapped with waterproof paper and plastic sleeves to preserve the zinc coating against moisture and salt spray during ocean freight
- Pipes sorted by diameter and wall thickness for efficient container loading, with 6-meter and 12-meter lengths configured to maximize 20-foot and 40-foot container capacity
- Custom cutting to project-specified lengths available, with cut ends deburred and protected against rust
- Each bundle marked with heat number, steel grade, outer diameter, wall thickness, and length for on-site identification and traceability
- FOB, CIF, and DDP shipping terms available, with professional loading plans for oversized pipes requiring open-top containers or flat-rack shipment
Initiating Your Welded Pipe Procurement
Submit your project drawings, steel grade requirements, outer diameter and wall thickness specifications, and destination port to receive a detailed quotation including material cost, fabrication charges, surface treatment, and shipping. The engineering team reviews shop drawings and confirms production schedules within 24 hours, with mill test certificates and third-party inspection reports included in the documentation package.
Request Your Q235 Q345 Welded Round Steel Pipe Quotation
Send your specifications and quantity requirements to receive pricing, mill test certificates, and delivery schedules.
- 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
- Address: No.11889, Jingshi West Road, Lulian Group, Jinan City, Shandong Province, China
Frequently Asked Questions
Q: What is the steel grade equivalence between Q235, Q345, and international standards like A36 or S235JR?
A: Q235B corresponds to A36 (ASTM) and S235JR (EN) in yield strength range, while Q345B aligns with S355JR (EN) and ASTM A572 Grade 50. The equivalence is based on minimum yield strength values, though chemical composition limits may vary slightly between standards. XJY Structure provides cross-standard material certification to support procurement under different specification systems.
Q: How does XJY Structure ensure wall thickness tolerance and material traceability for welded round pipe?
A: Every production batch undergoes ultrasonic thickness measurement at multiple points along the pipe length, with results documented in the mill test certificate. The integrated steel mill and fabrication facility ensures full heat number traceability from raw slab to finished pipe, eliminating third-party sourcing gaps. Third-party inspection by SGS or BV is available before shipment to verify dimensional accuracy and weld quality.
Q: What surface treatment options are available for Q235 Q345 welded round steel pipe, and how do I select the right one?
A: Three surface treatment options are available: oiled for short-term rust protection during transit and indoor storage; painted for moderate atmospheric exposure and architectural color matching; and hot-dip galvanized per GB/T 13912 or ASTM A123 for outdoor or corrosive environments. Selection depends on the service environment, design life, and project specifications.
Q: What is the typical production lead time and delivery process for standard and custom sizes?
A: Standard sizes in common diameters and wall thicknesses ship within typical production lead times after contract and deposit confirmation. Custom sizes, special lengths, or non-standard surface treatments require additional production scheduling. The engineering team provides a detailed timeline during the quotation stage, including shop drawing approval, material procurement, fabrication, inspection, and shipping.
Q: Can XJY Structure handle oversized pipe shipping and provide complete export documentation?
A: Yes. Pipes exceeding standard container dimensions are loaded on open-top containers or flat-racks with professional lashing plans to prevent transit damage. Complete export documentation is provided, including packing list, bill of lading, certificate of origin, mill test certificates, and third-party inspection reports. FOB, CIF, and DDP shipping terms are available based on project requirements.
Get Your Q235 Q345 Welded Round Steel Pipe Quote Today
Submit your project specifications, steel grade requirements, and destination port to receive a detailed quotation with mill test certificates and delivery schedules.
- 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
- Address: No.11889, Jingshi West Road, Lulian Group, Jinan City, Shandong Province, China
