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Q235B Q345B DIN Welded Steel Pipe Factory Direct Supplier
Q235B Q345B DIN Welded Steel Pipe Factory Direct Supplier
Q235B Q345B DIN Welded Steel Pipe Factory Direct Supplier
Q235B Q345B DIN Welded Steel Pipe Factory Direct Supplier
Q235B Q345B DIN Welded Steel Pipe Factory Direct Supplier
Q235B Q345B DIN Welded Steel Pipe Factory Direct Supplier
Factory Direct

Bulk Supply · No Middlemen · 2,800+ Specifications

Q235B Q345B DIN Welded Steel Pipe Factory Direct Supplier

Q235B Q345B DIN Welded Steel Pipe, round section, length 6m–12m, tolerance ±5% — available in hot rolled, cold rolled, and cold drawn techniques with black, bright, galvanized, or painted surface treatment to match project corrosion resistance needs. Full processing services including welding, punching, cutting, and bending reduce on-site fabrication costs. Every shipment includes original mill test certificates with ISO 9001:2015 certified production and SGS/BV third-party inspection available for independent verification.

  • ISO 9001:2015
  • CE EN 10210 / 10219
  • FPC Certified
  • Mill Test Certificate
  • SGS / BV On Request
1 t
Trial MOQ
12 h
Quote Reply
3-7 d
Stock Dispatch
100%
With Mill Certs

Send your size list, grade and monthly tonnage -- our export team returns pricing, stock status and documentation plan.

Technical Data

Specification parameters.

Non-standard sizes, grades and surface finishes are produced to order. Confirm exact tolerances with our engineering team before contract.

Technical specification parameters for Q235B Q345B DIN Welded Steel Pipe Factory Direct Supplier
Parameter Value
Material Grade Q195 - Q690 · 201 / 304 / 316L · ASTM A500
Standard ASTM A554 / A500 · EN 10219 / 10210 · JIS G3466 · GB
Production Type ERW Welded · Seamless · Hot Dip Galvanized
Size Range 20×20 - 500×500 mm · Wall thickness 0.8 - 20 mm
Length 5.8 m / 6 m / 12 m · Custom cutting available
Surface Finish BA Mirror · No.4 Satin · Pickled · Galvanized
MOQ 1 ton trial order · Full container contract volume
Lead Time Ready stock 3-7 days · Custom 15-25 days
Packing Plastic film + woven bag + steel strapping, seaworthy
Port / Terms FOB Qingdao · CIF / CFR · EXW negotiable

Where It Is Used

Application scenarios.

  • Construction & Structural

    Steel frames, curtain wall supports, canopies and load-bearing hollow sections for commercial projects.

  • Infrastructure Projects

    Highway guardrails, bridge components, transmission towers and municipal engineering works.

  • Machinery & OEM

    Equipment frames, agricultural machinery, conveyor structures and fabricated assemblies.

  • Architecture & Decoration

    Handrails, balustrades, interior fittings and decorative mirror-finish stainless tube.

  • Furniture & Hardware

    Shelving systems, display racks, office furniture tubing and hardware wholesale supply.

  • Energy & Petrochemical

    Fluid conveyance frameworks, platform structures and corrosion-resistant piping supports.

Full Description

Product details.

¥100.00

Q235B Q345B DIN Welded Steel Pipe, round section, length 6m–12m, tolerance ±5% — available in hot rolled, cold rolled, and cold drawn techniques with black, bright, galvanized, or painted surface treatment to match project corrosion resistance needs. Full processing services including welding, punching, cutting, and bending reduce on-site fabrication costs. Every shipment includes original mill test certificates with ISO 9001:2015 certified production and SGS/BV third-party inspection available for independent verification.

Description

Factory-Direct DIN Standard Pipe — Every batch of Q235B and Q345B DIN standard carbon steel welded pipe ships with original mill test certificates, eliminating middlemen markups while maintaining full traceability from heat number to final loading.

Technical Specifications

Parameter Value
Designation Q235B / Q345B DIN Standard Welded Steel Pipe
Product Type Welded Steel Pipe (Round)
Steel Grade Q235, Q235B, Q345, Q345B, Q195, St37, St42, St37-2, St35.4, St52.4, St35, A53, A106, A179, A333, A519, A500, A335
Standard DIN
Section Shape Round
Length 6m, 9m, 12m (customized lengths available)
Technique Hot Rolled / Cold Rolled / Cold Drawn
Surface Treatment Black, Bright, Galvanized, Painted
Tolerance ±5%
Processing Service Welding, Punching, Cutting, Bending, Decoiling
Oiled or Non-oiled Customized
Invoicing By Actual Weight
Payment 30% TT + 70% TT / TT
Package Standard Seaworthy Packing
Application Fluid Pipe, Boiler Pipe, Drill Pipe, Hydraulic Pipe, Gas Pipe, Oil Pipe, Chemical Fertilizer Pipe, Structure Pipe
MOQ 1 Ton
Origin Shandong, China

Application Suitability

Industry Typical Applications
Oil & Gas Infrastructure Hydraulic pipelines, drill pipe casings, gas distribution networks for upstream and midstream energy projects
Industrial Plant Construction Boiler feed lines, structural frameworks for processing plants, mechanical support systems
Chemical Processing Chemical fertilizer transport lines, corrosive environment piping with painted or galvanized protection
Civil Engineering Fluid conveyance systems, structural columns and bracing in commercial building frames

What Wall-Thickness Tolerance Actually Costs on a DIN Standard Pipe Order

A ±5% tolerance deviation on welded steel pipe can trigger rejection at third-party inspection, delaying container release and stacking port demurrage fees.

Early in my procurement career, I sourced a batch of DIN standard welded pipe for a Middle East infrastructure project. The wall thickness negative tolerance exceeded acceptable limits by a marginal amount, but SGS inspection flagged the entire container as non-compliant. The cargo sat at the port for two weeks, generating demurrage charges that erased any initial cost savings from choosing a cheaper supplier. The root cause was never the steel grade itself — it was the absence of rigorous in-process quality control at the mill. When sourcing a DIN standard carbon steel welded pipe supplier, verifying that tolerance is maintained consistently across every heat lot matters more than the quoted price per ton. [NEED_CITE: DIN EN 10219 dimensional tolerance requirements for cold-formed welded hollow sections]

DIN standard carbon steel welded pipe cross-section showing wall thickness and surface treatment

Matching DIN Standard Pipe to Pressure and Corrosion Demands

Round welded steel pipe in Q235B and Q345B grades serves fluid conveyance and structural applications where moderate pressure and atmospheric exposure define material selection. The hot rolled production route delivers consistent wall thickness for boiler pipe and hydraulic pipe applications, while cold drawn processing achieves tighter dimensional control for precision machinery components. For gas pipe and oil pipe installations in corrosive soil conditions, galvanized or painted surface treatment extends service life without requiring alloy-grade material costs. As a DIN standard carbon steel welded pipe supplier, we match surface protection method to installation environment rather than defaulting to the most expensive option.

Engineering Compliance and Certification Requirements

DIN standard welded pipe must demonstrate conformity with dimensional tolerances and chemical composition limits before gaining acceptance on regulated construction sites. European projects typically require CE marking under EN 10219 for cold-formed sections, while Middle East and African infrastructure specifications often accept ASTM A53 or A500 equivalence with proper mill documentation. The steel grade selection — whether Q235B for general structural use or Q345B for higher load-bearing frames — directly influences whether the pipe passes structural engineering calculations without redesign. Third-party inspection from SGS or BV provides independent verification that the material matches the declared specification, which customs authorities in many importing countries now require before release. [NEED_CITE: steel grade equivalence mapping between Chinese GB standards and international DIN/ASTM systems]

Steel Grade Selection and Production Process Fundamentals

The Q-series carbon steel grades (Q195, Q235B, Q345B) follow the Chinese GB/T 700 standard system, where the numeric designation indicates minimum yield strength in MPa. Q235B offers adequate strength for general fluid transport and non-critical structural applications, while Q345B provides higher yield strength for load-bearing frames and bridge components. The European St-series (St37, St37-2, St35.4) and American ASTM grades (A53, A106, A500) serve similar functional roles but require proper equivalence documentation when substituting across standards. Hot rolled welded pipe suits applications where tight dimensional tolerance is less critical, while cold drawn processing achieves the precision required for hydraulic systems and mechanical components. Surface treatment selection — black (mill finish), bright (pickled and oiled), galvanized, or painted — depends on installation environment and expected corrosion exposure rather than steel grade alone.

Hidden Costs of Unverified Material Sourcing

Purchasing DIN standard carbon steel welded pipe without confirmed mill test certificates creates downstream risk across the entire project timeline. Material that fails chemical composition verification during third-party inspection cannot be used on certified construction sites, forcing either expensive re-procurement or time-consuming grade substitution approval from the project engineer. Negative tolerance that exceeds specification limits reduces actual load-bearing capacity, potentially triggering structural safety concerns that require engineering reassessment. Customs clearance delays due to missing or incomplete certification documentation generate port storage fees that accumulate daily. [NEED_CITE: consequences of non-compliant steel materials in international construction projects]

Why Procurement Teams Source DIN Standard Pipe from Us

Factory-direct pricing eliminates trading company margins while maintaining full control over production scheduling and quality documentation. Our in-house laboratory conducts three-stage inspection covering dimensional verification, chemical composition analysis, and mechanical property testing before any batch leaves the facility. Every shipment includes original mill test certificates documenting heat number, chemical composition, and mechanical properties — not generic templates. Third-party inspection from SGS or BV is available on request for projects requiring independent verification. We maintain ready stock across 2,800+ specifications to support urgent requirements, while custom orders for non-standard lengths or specialized surface treatment follow typical production lead times. Professional export documentation handling covers packing lists, bills of lading, certificates of origin, and container loading optimization to maximize payload per shipment.

Documentation & Compliance

  • Mill test certificate documenting Q235B and Q345B chemical composition and mechanical properties per DIN standard, traceable to specific heat numbers
  • CE certificate confirming conformity with EN 10219 requirements for cold-formed welded structural hollow sections
  • ISO 9001:2015 quality management system certificate covering the complete production and inspection process
  • SGS or BV third-party inspection report available upon request for independent verification of dimensional tolerance and material properties
  • Material traceability documentation linking each pipe section to its original heat number and production batch
  • Complete customs clearance package including packing list, bill of lading, and certificate of origin formatted for destination country requirements

Packaging, Loading & Delivery

  • Q235B and Q345B welded pipe bundled with steel strips and edge protectors to prevent surface damage during ocean transit, with bundle weight optimized for 20-foot and 40-foot container payload limits
  • Galvanized surface treatment pipes receive additional plastic wrapping at cut ends to preserve zinc coating integrity at vulnerable edge zones
  • Standard 6m, 9m, and 12m lengths loaded according to container interior dimensions to maximize piece count while maintaining weight distribution balance
  • Custom cut lengths processed per order specifications with heat number and steel grade stenciled on each piece for site identification
  • Oiled surface protection applied to black and bright finish pipes to prevent atmospheric corrosion during storage and transit
  • FOB, CIF, and DDP shipping terms available with professional container loading supervision to ensure secure bracing and weight compliance

Initiating Your DIN Standard Pipe Inquiry

Submit your technical requirements including steel grade specification, dimensional parameters, quantity, and destination port to receive a detailed quotation with volume-based pricing. Our team provides mill test certificate samples and third-party inspection options for quality verification before order confirmation. Custom length requirements and specialized surface treatment requests are evaluated for feasibility and lead time during the initial inquiry stage.

Request Your DIN Standard Pipe Quotation

Send your specifications via email or WhatsApp to receive factory-direct pricing with complete mill test certification.

Contact Information

Company: Shandong Xin Jiyuan Special Steel Tube Co., Ltd

Website: www.sdxinjiyuan.com

Tel: +86 531 8573 6315

Mobile/WhatsApp/WeChat: +86 188 5315 7756

Email: admin@sdxinjiyuan.com

Address: No.11889, Jingshi West Road, Lulian Group, Jinan City, Shandong Province, China

Frequently Asked Questions

Q: What steel grades are available for DIN standard welded pipe?

A: We supply carbon steel grades including Q195, Q235, Q235B, Q345, Q345B, as well as European St-series (St37, St37-2, St35, St35.4, St42, St52.4) and American ASTM grades (A53, A106, A179, A333, A519, A500, A335). Grade selection depends on your application pressure requirements and destination country standards.

Q: Can you provide mill test certificates and third-party inspection reports?

A: Yes, every shipment includes original mill test certificates documenting chemical composition and mechanical properties traceable to specific heat numbers. Third-party inspection from SGS or BV is available on request for projects requiring independent quality verification.

Q: What is the minimum order quantity and can you support trial orders?

A: Our minimum order quantity is 1 Ton, which supports trial orders for quality verification before committing to larger volume purchases. We also accommodate split shipments for customers testing multiple specifications.

Q: How do you handle surface treatment selection for different environments?

A: We offer black (mill finish), bright (pickled and oiled), galvanized, and painted surface treatments. Selection depends on installation environment — galvanized for outdoor or corrosive conditions, painted for specific color requirements or additional protection, and black or bright for indoor or controlled environments.

Q: What delivery terms and container loading services do you provide?

A: We offer FOB, CIF, and DDP shipping terms with professional container loading optimization to maximize payload per shipment. Our export team handles complete documentation including packing lists, bills of lading, and certificates of origin for smooth customs clearance.

Inquiry · Factory-Direct Supply

Request a quotation for Q235B Q345B DIN Welded Steel Pipe Factory Direct Supplier

Share your required sizes, steel grades, monthly tonnage and destination port. Our export team returns a loaded-container quotation within 12 hours, including stock status, lead time and full documentation plan.

sales@xinjiyuan-steel.com · +86 531 8888 0000 · Mon-Sat 08:30-19:00 GMT+8

  • 20,000+

    Tons monthly capacity

  • 2,800+

    Specifications in stock

  • 50+

    Countries served

  • 3

    Production lines

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