Counting On Improved OEE

The machines turn metal bar stock into a variety of small internal parts for Moen assemblies. First, the company was unsure of exact output, since the machines, while still highly capable, used older, weight approximation to estimate the count. Second, the equipment had intermittent feed errors as well as fluctuating outages of raw stock – bad feed can mean bad product and, of course, no stock means no product.Moen approached Rockwell Automation to help enhance manufacturing performance management. A critical objective was an absolutely accurate count of the number of parts each screw machine operator produced in a given day, allowing Moen to identify potential problems before they occurred. Plus, with ever-increasing overseas competition, Moen also sought to ensure maximum availability. “The need to keep our productivity as high as possible has become increasingly critical,” said Steve Zurcher, lead production coach, Moen. “We had to find a way to access rate versus cycle time, part count and overall operating parameters of our machines.”No Solution AvailableEven though screw machines are ubiquitous in industries from automotive to building supplies, Moen found no ready-made solutions to screw machine down time. Moen turned to long-time supplier Rockwell Automation to implement a manufacturing execution system (MES)—not just for the screw machines, but for operations in general.The resulting MES, based on Rockwell’s FactoryTalk production and performance management software, helps Moen measure and control its critical processes. At the same time, it helps increase traceability, productivity and quality. The system also provides other functions, including inventory management, equipment and labor tracking, and quality and resolution monitoring. In particular, the system provides Moen with a mix of software integration tools and applications for improved access to plant-floor information.The FactoryTalk Metrics component of the MES provides production data flow for rapid response to changing manufacturing situations. Where operators previously logged delays manually—and sometimes inaccurately—the system now automatically logs delays in a fraction of a second. The software application also serves as a basis for understanding the real causes of inefficiency, waste, lost capacity and equipment status. The result for Moen is a 10 percent increase in screw machine productivity in less than a year. Plus Moen has been able to increase OEE on most screw machines by nearly 30 percent, thanks to accurate part count. The count data also allows management to schedule preventative maintenance and minimize downtime.The automation solution from Rockwell Automation also provided Moen with an added benefit: any abnormal voltage and cycle time data also helps production management predict machine breakdown.“We were looking for a better handle on our productivity,” says Zurcher. “What we didn’t expect was a tamper-proof way to count parts and directly compare cycle-time to rate. The benefits of the Rockwell Automation solution have helped us remain competitive in an increasingly crowded industry.”Dave Gehman is an Automation World Contributing Editor.