Green Sand Aluminum Casting
Efficient, Repeatable Aluminum Castings for Production Applications
Cast Metals Technology provides green sand aluminum casting for manufacturers requiring dependable, repeatable production of aluminum components.
With both automated and manual molding capabilities, CMT can support a wide range of casting sizes, geometries and production volumes while providing customers with engineering, tooling, core making, heat treatment and CNC machining from a single aluminum casting supplier.
Our foundry operations in Ohio and Indiana serve manufacturers throughout the United States and North America.
Have a new casting or an existing program you need to re-source?
What Is Green Sand Aluminum Casting?
Green sand casting is a manufacturing process in which prepared molding sand is compacted around a pattern to create the cavity that forms the finished aluminum component.
The term “green sand” does not describe the color of the sand. It refers to molding sand that contains moisture when the mold is produced.
After the pattern is removed, any required sand cores are positioned in the mold. The mold is closed and molten aluminum is poured into the cavity.
After solidification, the mold is broken apart and the aluminum casting moves through finishing, inspection, heat treatment and machining operations as required.
Why Use Green Sand Casting?
Efficient mold production
Competitive cost per casting
Repeatable medium- and high-volume production
Complex external geometries
Internal features produced with sand cores
Multiple aluminum alloy options
Long production-tool life
Scalability as production requirements increase
Lower tooling investment than some alternative casting processes
Automated Green Sand Molding
Automation can significantly improve the productivity and repeatability of green sand casting.
CMT utilizes automated molding technology to support production programs requiring consistent, repeatable output.
- DISA, Hunter and Roberts Sinto automated molding machines are utilized at CMT
- Repeat production programs
- Medium- and high-volume components
- OEM production
- Long-running casting programs
- Components requiring consistent mold geometry
- Programs where production efficiency is critical
Manual Green Sand Casting
Automation is not the correct solution for every casting. Manual green sand molding provides additional flexibility for components and production quantities that may not justify automated production.
What Parts Are Good Candidates for Green Sand Casting?
Pump components
Electrical powerline hardware
Compressor and blower components
Housings
Brackets
Covers
Electrical enclosures
Agricultural equipment components
Power-generation components
HVAC components
Construction-equipment components
Material-handling components
Industrial machinery components
Complex Aluminum Castings Using Sand Cores
An important advantage of aluminum sand casting is the ability to create complex internal geometry with sand cores.
- Internal cavities
- Flow passages
- Hollow sections
- Deep pockets
- Internal chambers
- Complex geometry that would otherwise require extensive machining
CMT supports multiple core-making processes, including shell, Isocure, air-set and 3D printed cores.
Green Sand Casting Design Considerations
Good casting design starts with a few core principles. For a deeper look, read our article on designing for aluminum sand casting.
Draft
Draft allows the pattern to release properly from the sand mold without damaging the mold cavity.
Wall Thickness
Maintaining appropriate and reasonably uniform wall thickness can improve metal flow and solidification.
Fillets and Radii
Smooth transitions can improve metal flow and reduce stress concentrations compared with abrupt changes in section thickness.
Parting Line
Parting-line location affects tooling, molding, finishing and the overall manufacturability of the casting.
Cores
Internal features should be designed with consideration for how cores will be produced, supported and removed.
Machining Allowance
Surfaces requiring CNC machining need adequate material to allow the final dimensions and finish to be achieved.
Green Sand vs. Air-Set Aluminum Casting
Both processes use sand molds, but they serve somewhat different manufacturing requirements.
Green sand is often particularly effective for repeat medium- and high-volume production. Air-set/no-bake provides additional flexibility for larger, complex and lower-volume castings.
Aluminum Alloys
- A356
- 319
- 355
- 359
- 535
- 713
Heat Treatment and Secondary Operations
- Heat treatment
- Shot blasting
- Vibratory finishing
- Machining
- Anodizing
- Powder coating
- E-coating
- Other finishing operations
Green Sand Castings + CNC Machining
- CNC milling
- CNC turning
- Live-tool turning
- 4-axis machining
- 5-axis machining
- CMM inspection
- Balancing
Transferring Existing Green Sand Tooling
Already have a production casting at another foundry?
CMT can evaluate existing patterns, match plates, core boxes, gating systems and fixtures.
Cast Metals Technology is an industry leader in helping our customers with, Capacity constraints, Delivery performance, Quality solutions, Lead Time Reduction, Supplier consolidation, Second-source requirements
Capacity constraints
Delivery performance
Quality solutions
Lead Time Reduction
Supplier consolidation
Second-source requirements
Looking for a Green Sand Aluminum Casting Foundry?
Whether you are developing a new component or looking for a new source for an existing casting, Cast Metals Technology can review your application.
Comparing suppliers? Read our guide to choosing an aluminum sand casting foundry.
American-Made Aluminum Castings and Machining