Sand casting is an ancient process, but foundries are continuing to innovate. This is being driven by a combination of customer and competitive pressures, plus environmental and regulatory changes and expectations. Leading foundry operators like Impro are constantly monitoring advances, and implementing those showing real benefits for customers and themselves. Here’s a look at what’s happening.

Drivers of Innovation

Companies using metal castings are under intense pressure to refine existing products and launch new ones faster than ever before. In parallel, they need to reduce costs, which means reducing waste, seeking out the most efficient suppliers, and minimizing operations like machining.

At the same time, while constantly seeking higher efficiencies, foundries are coming under scrutiny for their environmental impact. This is pushing them to examine cost and emission factors like sand consumption, recycling, energy efficiency and emissions.

The resulting drive for innovation is following three vectors:

• Improved casting capabilities: Shorter lead times, higher precision
• Increased efficiency: Adopting Industry 4.0 digital technologies for automation and optimization
• Greater sustainability: Reducing waste and increasing recycling, cutting energy consumption and emissions

For each of these, technological advances are opening up new opportunities.

Casting Capabilities

• 3D printing: Instead of using patterns, that take time to develop and require draft angles, sand molds can now be printed directly using a process called “binder jetting”. This lets the foundry produce initial parts in less time.
• Sand compaction: Equipment manufacturers are constantly improving the way in which sand is moved into and compacted in the cope and drag, (the two halves of the flask that form the mold cavity). This results in more uniform density, which means more accurate castings that need less machining.
• New binder systems: Inorganic binders eliminate off-gassing caused when hot metal enters the cavity. This prevents gas-related defects while improving mold precision and supporting 3D printing.

Efficiency Improvements

• Real-time process monitoring: Instrumenting casting machinery with sensors for parameters like temperature and pressure permits closer control over the process. Going further, emerging Artificial Intelligence (AI) tools are delivering predictive analytics capabilities that recommend process adjustments to increase yield and reduce cycle times.
• Simulation and modeling: The tools used to optimize mold design are constantly being refined and improved. These help foundries reduce scrap and improve quality while at the same time cutting tooling lead time.
• Automation: Equipment manufacturers continue to improve casting machinery, but improvements are also being seen in secondary and finishing activities. Sand reclamation is becoming highly automated, as is the initial fettling or grinding of castings broken or shaken out of their sand molds. (Fettling automation also means workers no longer have to perform a dirty and hazardous job.)

Sustainability

• Sand reclamation: Sand is becoming expensive and increasingly hard to dispose of. Reclaiming the sand reduces consumption and eliminates the need to send it to landfill. In addition, switching to inorganic binders reduces usage of chemicals and supports sand recovery processes.
• Waste reduction: Sand reclaimation is one aspect of waste reduction, but so too is improvement in yields through real-time process monitoring and improved mold filling simulation.
• Energy efficiency: Higher yields support energy saving and emissions reduction goals. In addition, new foundry machinery is designed to minimize thermal losses. Plus, some foundries are implementing heat recovery systems to reduce energy waste.

Partner With a Sand Casting Leader

Sand casting is a mature and proven method of producing metal parts that need little secondary machining. However, driven by a combination of internal and external factors, foundries and equipment suppliers continue to make improvements.

The technological advances discussed here are helping companies like Impro meet the needs of the most demanding customers. They also let us react to regulatory and environmental challenges. If you have a need for high quality metal castings, Impro can almost certainly help. Contact us to arrange a discussion.