Ductile Cast Iron
Ductile iron refers to cast iron in which the graphite is spheroidal after the molten iron is treated with a spheroidizing agent. That is why the ductile cast iron is also called spheroidal graphite cast iron or nodular cast iron. Inside the ductile cast iron by electron microsope, the shape of spheroidal graphite is approximately spherical, and its interior is radial shape, and it has obvious polarization effect.
Ductile iron has better strength-to-weight ratio, better machinability and higher impact value. Moreove, the ductile iron components are produced by casting process wherein better control of component shape can be achieved compared to drop forging. Thus, many a component such as crank shafts and connecting rods manufactured usually by drop forging is increasingly being replaced by ductile iron castings.
Capacities for Ductile Iron Castings
- Ductile (Nodular) Cast Iron: EN-GJS-400-18, EN-GJS-40-15, EN-GJS-450-10, EN-GJS-500-7, EN-GJS-600-3, EN-GJS-700-2, EN-GJS-800-2 or Their Equivalent Grades
- Max Size of Casting Molds: 1,000 mm × 800 mm × 500 mm
- Weight Range of Ductile Iron Castings: 0.5 kg - 500 kg
- Annual Capacity of Ductile Iron Castings: 8,000 tons - 10,000 tons
- Casting Tolerances: On Request or According to ISO 8062
Sand Process Equipment
Metal Sand Casting
Inspection Capabilities for Ductile Iron Castings
Our Spectrometer checks 15 chemical elements and metallurgical microscope produces high-resolution images 1,000 times magnified, and our cleanliness meter determines particle size and quantity to ensure materials meet or exceed the international standard. RMC use ultrasonic detectors to discover flaws, and have X-ray machines and accelerators that can scan castings with 200 mm maximum wall thickness.
RMC has a full range of inspection capabilities in house, which include:
- Spectrographic and manual quantitative analysis
- Metallographic analysis
- Brinell, Rockwell and Vickers hardness inspection
- Mechanical property analysis
- Low and normal temperature impact testing
- Cleanliness inspection
- UT, MT and RT inspection
Sand Molding Machine
Finished Sand Castings
Applications of Ductile Iron Casting Components
Sand casting parts could serve in many industries including hydraulics, automotive, commercial truck, rail trains, logistics, agricultural machinery...etc. The castings mainly are used as gearbox housing, pressure pump housing, engine blocks, cylinder heads, transmission box, bracket, wheel hub, connecting rods, manifolds...etc.
Typical Ductile Iron Castings
Value Added Services for Ductile Iron Castings
Our services are varied and extensive. We offer material advisory service and development, as well as advice from our technical experts on design and casting with under the help of the software of 3D and CAD drawings and simulations software. From start to finish, we have you covered every step of the way.
- Sand Casting: Green Sand Casting with Handle and Automatic Molding Machine, Pre-Coated Shell Molding Casting, CNC Precision Machining and Metal Fabrications.
- Heat treatment: Quenching, Tempering, Normalizing, Annealing, Carburization, Nitration
- Surface treatment: Anodizing, Zinc-plating, Polising, GeoMet, Zintek, Electrophoresis....etc
- Testing Service: Chemical Composition, Mechanical Properties, Fluorescent or Magnetic Penetration Inspections (FPI, MPI), X-rays, Ultrasonic Testing, Dynamic and Static Balancing Testing
RMC offers a full range of sand casting solutions. If you would like to know more about our technology and sand casting process capabilities, contact us today.
FAQs About Sand Casting
• When Sending a New Part for Quotation (Request for Quotation, RFQ), What are the Key Information We Need to Provide to RMC?
• 2D drawings with dimension tolerances and/or 3D models which we can use for calculating the unit weight easily
• Material specification including heat treatment and required mechanical properties (if needed)
• Quality assurance expectations
• Special finishing/surface treatment requirements
• Tooling if required or existing
• Due date of quote response
• Application of the part you are asking
• How Do You Use the Information We Provide?
Before we make recommendations for the project and provide you with an offer, RMC firstly analyzes the following information to make our decision and proposals based on the request information you sent:
• Tooling requirements – best suited to scope of your project
• Quality expectations required to support your technical specifications
• Machining requirements
• Heat treatments
• Finishing requirements
• Expected date of delivery
• How Do You Determine Which Alloy is Best for Our Project?
Each alloy serves a difference purpose based on issues as diverse as heat exposure, run time, weight requirements, flexibility of the end product and so on. We work with you to determine exactly how your component need to perform and then guide you to the best alloy whether you need: Cast Iron, Cast Aluminum, Gray Iron, Cast Copper Alloy, Ductile Iron, Gray Iron, Cast Steel, Zinc Alloys, Stainless Steel and any other possible metal and their alloys.
• How Does Product Design Affect Casting Methods?
Casting is one of the fastest and most cost effective methods for producing a wide range of components. However, to achieve maximum benefits, you’ll want to involve the cost analysis at an early stage of the product design and development. We have the expertise and experience to consult with you during the design phase so our engineers can help resolve issues affecting tooling and production methods, while identifying the various trade offs that could affect overall costs.
• How Are Sand Castings Made?
We have different casting types for your choice. Part of the optional process for your project will be the selection of the casting process. The most popular form is sand casting which involves making a replica of a finished piece (or pattern) that is compressed with sand and binder additives to shape the final part. The pattern is removed after the mold or impression has been formed, and the metal is introduced through a runner system to fill the cavity. The sand and the metal are separated and then the casting cleaned and finished for shipment to the customer.
Moreover, we also have the shell molding process produce the iron castings and steel castings. The shell molding is usually use resin coated sand for making molds.
• What Are the Typical Lead Times?
Lead times with sand casting, investment casting, forging and machining vary due to part complexity and casting plant capacity. Generally 4-6 weeks is typical for tooling and sample castings and 5-7 weeks for production. Once a pattern is created, a component can be produced in seven days. For investment casting processes, much of this time is spent with the coating and drying of the ceramic slurry. While for sand casting, the time is mainly cost for the mold making. Investment casting facilities in RMC have quick drying capabilities for ceramic molds to produce parts in 24-48 hours. In addition, by using silica sol or water glass as bond material, engineered cast metal components can be delivered only several days after accepting a final CAD/PDF drawings or 3D models.
• Can You Provide the 3.1 Material Certificate?
Yes, we could provide the 3.1 material certificate if you request.
• What Dimensional Tolerances Can Be Achieved by Sand Casting?
Typically, we can achieve the tolerance grade as per the requirements for sand casting according to ISO 8063. This would vary depending on the size and complexity of the part. Post-casting procedures, such as straightening or coining, often allow for tighter tolerances to be maintained on several specific dimensions.By working with our engineering staff, an investment casting drawing can be produced for a part that substantially reduces or completely eliminates the previous machining requirements to produce an acceptable component.