Top 10 Ductile Iron Casting Factories in China (2025) – Trusted OEM Suppliers

As China continues to lead the global foundry industry with its advanced manufacturing capabilities, the country’s ductile iron casting sector has achieved remarkable progress in both technological innovation and production scale. We delve into the top 10 ductile iron casting factories in China for 2025, providing insights into their capabilities, certifications, and specialties.

Criteria for Selecting Top Factories

When evaluating ductile iron casting factories, several critical factors come into play:

• Production Capacity: Ability to handle large volumes efficiently.

• Quality Certifications: Compliance with international standards like ISO 9001.

• Technological Capabilities: Advanced machinery and casting techniques.

• Customization and OEM Services: Flexibility to meet specific client requirements.

• Global Reach: Experience in exporting and serving international markets.

• Reputation and Reliability: Track record of delivering quality products on time.

Top 10 Ductile Iron Casting Factories in China

1. Xinxing Ductile Iron Pipes Co., Ltd.

• Overview: A leading manufacturer specializing in ductile iron pipes and fittings.

• Certifications: ISO 9001, ISO 14001.

• Key Products: Pipes, fittings, and related components.

• Global Reach: Extensive export network across Europe, Asia, and Africa.

2. Shanxi Jingang Luokaiwei Co., Ltd.

• Overview: One of China’s largest steel producers with a dedicated ductile iron casting division.

• Certifications: ISO 9001, ISO 14001.

• Key Products: Automotive parts, machinery components.

• Global Reach: Strong presence in international markets.

3. Taiyuan Iron & Steel (Group) Co., Ltd.

• Overview: Renowned for high-quality steel and iron products, including ductile iron castings.

• Certifications: ISO 9001, ISO 14001.

• Key Products: Industrial machinery parts, construction components.

• Global Reach: Exports to over 50 countries.

4. Shandong Jinlong Machinery Group Co., Ltd.

• Overview: Specializes in ductile iron castings for various industries.

• Certifications: ISO 9001.

• Key Products: Automotive parts, agricultural machinery components.

• Global Reach: Strong client base in Europe and North America.

5. Ningbo Yinzhou Leisheng Machinery Co., Ltd.

• Overview: Offers comprehensive casting solutions, including ductile iron products.

• Certifications: ISO 9001.

• Key Products: Valve parts, pump components.

• Global Reach: Exports to Europe, America, and Southeast Asia.

6. Yide Casting Co., Ltd.

• Overview: Provides customized ductile iron casting services.

• Certifications: ISO 9001.

• Key Products: Automotive parts, machinery components.

• Global Reach: Serves clients in over 30 countries.

7. Dawang Casting Foundry

• Overview: Offers a wide range of casting services, including ductile iron.

• Certifications: ISO 9001.

• Key Products: Construction machinery parts, industrial components.

• Global Reach: Exports to North America and Europe.

8. Shandong Useen Casting Co., Ltd.

• Overview: Specializes in high-quality ductile iron products as a trusted OEM manufacturer.

• Certifications: ISO 9001.

• Key Products: Counterweights, machine tool castings.

• Global Reach: Strong presence in international markets.

9. Maple Machinery

• Overview: A one-stop manufacturer with casting, forging, and machining capabilities.

• Certifications: ISO 9001.

• Key Products: Agricultural machinery parts, automotive components.

• Global Reach: Exports to North America and Europe.

10. Qingdao Antai Import and Export Co., Ltd.

• Overview: Offers specialized foundry services for ductile iron casting.

• Certifications: ISO 9001.

• Key Products: Machinery parts, industrial components.

• Global Reach: Serves clients in Asia, Europe, and America.

Comparative Analysis of the Top Factories

Technical Capabilities: How Chinese Foundries Excel

Material Innovation
Leading factories now produce enhanced grades:

• SiMo 1000: Heat resistance to 850°C for exhaust manifolds

• Ductile Iron EN-GJS-500-14: 14% elongation for earthquake zones

• Austempered Ductile Iron (ADI): Tensile strength to 1600 MPa

Production Processes

• Molding: Shell molding (YQ-China) for complex geometries <3mm thick 3

• Melting: Computer-controlled induction furnaces ±10°C accuracy

• Nodularization: Magnesium treatment with automated T-scan analysis

Quality Assurance: Certifications That Matter

Mandatory Certifications

• ISO 9001:2015 (Quality Management)

• ISO 2531:2020 (Water Pipelines)

• ISO 14001 (Environmental Management)

Industry-Specific Compliance

• Water Sector: NSF/ANSI 61, WRAS, KTW

• Automotive: IATF 16949 (MEIDE Group)

• Energy: PED 2014/68/EU for pressure equipment

Testing Protocols

1. Spectrometer chemical analysis

2. Ultrasonic thickness mapping

3. Charpy impact tests (-30°C to +25°C)

4. 3D scanning for dimensional accuracy

Global Export Logistics: Best Practices

Shipping Optimization

Critical Documentation

• Mill Test Certificates (EN 10204 3.1/3.2)

• Origin declarations (Form A for GSP countries)

• Pressure test reports for valve/piping components

OEM Collaboration Models

Proven Strategies for Custom Projects

1. Design Phase:

   • Submit CAD drawings (STEP/IGES format)

   • Request material test coupons

   • Agree on FAI (First Article Inspection) protocol

2. Production Phase:

   • Weekly video audits (e.g., core assembly, pouring)

   • Witness critical tests (hydrostatic, impact)

3. Logistics Phase:

   • Use Incoterms CIP for insurance coverage

   • Schedule SGS pre-shipment inspection

Cost Drivers for Custom Orders

• Pattern creation: $2,000–$15,000 (reusable)

• Alloy surcharges: +15–40% for Ni/Cr/Mo additives

• Accelerated production: +25% for 50% time reduction

Frequently Asked Questions (FAQs)

Q1: What’s the minimum order quantity for custom ductile iron castings in China?
Most factories require 500 kg to 3 tons for OEM projects, though exceptions exist. YQ-ChinaTransmissions accepts 100-kg orders for gear components when using existing molds 3, while large pipe specialists like Xinxing enforce 5-ton MOQs. Three factors dramatically affect MOQs:

• Pattern complexity: Simple flat plates (lower MOQ) vs. multi-core engine blocks.

• Material grade: Standard EN-GJS-400-18 (lower MOQ) vs. high-nickel alloys.

• Post-processing: As-cast surfaces (lower MOQ) vs. full machining/coating.
  For prototyping, expect MOQs of 1–5 pieces with unit costs 3–8x mass production pricing. Leisure Trading Company offers shared-mold programs where clients split tooling costs for standard fittings.

Q2: How do I verify material grades when ordering from China?
Implement a 4-stage verification protocol:

1. Pre-production: Demand mill test reports for incoming iron (SGS-verified).

2. Pouring samples: Require spectrometer analysis of each heat (reporting C, Si, Mn, P, S, Mg).

3. Mechanical testing: Witness tensile/impact tests (per ISO 6892 or ASTM E8).

4. Third-party audits: Hire TÜV or Bureau Veritas for unannounced factory inspections
   Reputable suppliers like Angang Yongtong provide EN 10204 3.2 certificates with traceable heat numbers 10. For critical components, insist on retaining production samples for independent lab testing.

Q3: Can Chinese foundries produce ADI (Austempered Ductile Iron) components?
Yes, MEIDE Group and TISCO lead in ADI production for automotive applications. Their processes achieve:

• Grades: EN-GJS-800-8 to EN-GJS-1400-1

• Typical applications: Gearboxes (replacing forged steel), mining shovel joints, rail bogies

• Process control: Computerized austenitizing (900°C) and austempering (350°C) baths
  However, confirm these critical capabilities:

• In-house austempering facilities (not subcontracting)

• ISO 17804 or ASTM A897 certification

• Charpy impact test reports at -40°C
  ADI typically costs 20–35% more than standard grades but offers 3x fatigue strength.

References:

• ISO 9001:2015 – Quality Management Systems
• ISO 2531:2009 – Ductile Iron Pipes, Fittings, Accessories and Their Joints for Water Applications
• ISO 14001:2015 – Environmental Management Systems
• NSF/ANSI 61 – Drinking Water System Components – Health Effects
• IATF 16949:2016 – Automotive Quality Management System