Automated Foundry Grinding Improves Productivity and Efficiency for Aerospace Manufacturer

The modern foundry industry faces several key challenges, including a persistent labor shortage, stringent safety requirements, and demanding working conditions that often deter new talent.

Simultaneously, the global manufacturing landscape is witnessing an accelerating trend toward automation, driven by the need for increased efficiency, consistency, and reduced operational costs. This shift is extending into traditionally labor-intensive sectors like foundries, where automated solutions for applications such as grinding are emerging as critical technology to address these pressing issues, offering the potential to enhance productivity and results, improve worker safety, and alleviate the strain of manual processes.    

Benefits of Automation in Foundry Grinding 

Automating the grinding process in a foundry offers several significant benefits, addressing key challenges faced by the industry. These benefits include:

• Improved worker safety: Grinding is a physically demanding and potentially hazardous task, exposing workers to dust, heat, noise, vibrations and flying debris. Automating the grinding process mitigates the safety concerns associated with manual grinding, significantly reducing the risk of injuries such as carpal tunnel syndrome or other safety issues that can result from operator fatigue. Reducing these safety risks can also help facilities address labor shortages and challenges with worker retention in these dirty and hot environments.
• Enhanced efficiency and productivity: Robotic grinding systems operate continuously using higher grind pressures without breaks or fatigue, leading to higher production rates and more uniform product quality. This eliminates the variability associated with manual grinding, where fatigue and human error can affect results. Automation can result in more parts produced per shift so it can also help operations address labor shortages, as they can do more with less workers.
• Reduced costs: While automation for material removal and grinding requires substantial investment up front, it generates cost savings in multiple areas, resulting in relatively short return on investments. Automation provides the potential for reduced labor costs (if the work can be completed with fewer people), lower media consumption, and improved quality, which all play a role in overall unit costs. A robotic cell can also use software to assess abrasive media life. The software determines how much life is left of an abrasive to ensure each abrasive is used to its full life, helping reduce media costs and extend media life three to four times when compared to manual operations.
• Improved quality: The use of robotics generates precise and repeatable grinding operations. This leads to improved dimensional accuracy and surface finish, reducing the need for rework and improving overall product quality.   

Implementing Automation in Foundries 

There are numerous foundry grinding applications that are well-suited for automation, including gate removal, edge radiusing, defect removal, and skeleton cut off. However, there are several considerations to keep in mind before implementing automation for a material removal process.

First, be aware that when using automation for grinding and material removal, the process in many cases may not get to 100% of the finish requirements needed. A robotic grind cell will typically achieve 80% or more of the material removal necessary. The remaining material removal would then be completed manually or in a machining operation. But the capability of robotic cells to get the finishing process to that point will cut down significantly on the necessary manual or CNC time — savings that can still make automation worth the investment.

It's important to fully understand the desired grinding process results before implementing automation. This will dictate what cell capabilities and equipment are required. Otherwise, the cell could end up with components that have the wrong horsepower, wrong spindle speeds or even wrong abrasive media. Another key factor is not to just duplicate the existing manual grind process as the robot is faster, more accurate and capable of generating higher grind pressures, which allows for the use of much more aggressive and longer-lasting (harder) grinding media than manual processes.

Working with a robotic integrator that can provide expert consultation and analysis is the best way to develop an appropriate automation solution. It’s important to look for a partner with robotic programmers who are experienced at material removal applications, not just general robotic applications. You should also work with abrasive specialists who understand foundry grinding processes. Since implementation of automation may impact the entire process including both upstream and/or downstream operations, partnering with experienced material removal experts is critical.

Automation Saves Time for Aerospace Manufacturer 

In one recent real-world example, a manufacturer of aerospace engine components was struggling to efficiently grind the inner diameter of titanium rings. The rings were smaller in size, with inside diameters of 2.5” to 6.5”, making it difficult for operators to reach into them for grinding. Operators also had to flip the rings end for end during the grinding process, adding considerable safety issues and time to the process. 

The manufacturer wanted to investigate using automation with more aggressive media for this grinding process. This facility has used automation before for other applications that utilized coated abrasive belts but this would be their first automated process using organic bonded abrasives similar to their existing manual processes.

To develop a solution for this manufacturer, Weiler Abrasives worked with Acme Manufacturing, a robotic systems integrator and machine tool builder that specializes in robotic material removal processes such as grinding, polishing, buffing, deburring, and cut-off. Weiler and Acme have a long history of working together on many successful projects for end users. 

“This automation project was for a very specific application; our team went through rigorous testing to determine the correct finishing approach. That’s one reason why it’s so important to work with a partner who has experience in automating material removal,” says John McGrane, Director of Marketing Communications, Acme. “Weiler worked very closely with us to determine the abrasive needs to help achieve the results we needed for this end user.”

After testing and confirmation of the media types and operating parameters required, a new robotic grinding cell was designed and built by Acme. It can manipulate the part, pick up a tool and automatically change the media as needed. The interior diameter of each ring may have unique variations; the system uses the abrasives to grind away imperfections and remove potential cracks before the part is sent for further processing. The robotic cell has two different work holding locations to accommodate different sized parts. It also dresses the media each time, ensuring that it has new grain exposed for maximum sharpness to provide a repeatable finish.

Weiler experts recommended the media required for this project and provided technical support regarding factors like angle of approach, pressure required, and the RPM used. Because this aerospace application uses high-strength alloy materials, it required some initial media testing to determine the best operating parameters for this specific application. Those parameters determined the required spindle rpm and horsepower. Weiler bonded abrasives used on the robotic cell include snagging wheels, plugs and Type 11 cups. Weiler was also on site at the end user for the cell’s initial start-up to assist with any process refinements that may have arisen since this was the first time this end user had automated this specific grinding process.

The end user was able to reduce the grinding time from about 30 minutes for the manual process to 7 to 18 minutes per cycle depending on part size for the automated process.

“Automation can save significant time, and this user was very satisfied with the results,” McGrane says.

One area where end users can see great improvements with automation is the extension of abrasive media life, since the robotic cell can manage media life and notify operators when a change is needed.

“The robot can be a lot more efficient with an abrasive compared to a human operator. It’s really using the full life of an abrasive,” McGrane says. “We say the media life is typically three to four times longer.”

Addressing Foundry Challenges 

Automation offers a multitude of benefits for foundry grinding applications, including enhanced worker safety, improved efficiency and productivity, reduced costs, and improved quality. By mitigating safety risks, increasing production rates, ensuring consistent quality, and optimizing abrasive usage, automated grinding cells can address critical challenges faced by the foundry industry.