System integrator partners with Rockline Industries to increases OEE
Each of five manufacturing cells have demonstrated an OEE increase of more than 20% compared to the prior system implementation
Americans are more germ-conscious than ever, which is helping fuel the demand for hard-surface disinfectant wipes, which remove bacteria and viruses on everything from kitchen counters to doorknobs. Convenience is another major factor: One can pull the ready-to-use wipes from a plastic canister instead of turning to the more traditional spray-and-paper-towel method of household cleaning.
Rockline Industries has built a healthy business by manufacturing these disposable, private label wipes for major retailers. At its Sheboygan, Wis., plant — one of seven the company operates globally — Rockline produces millions of wet-wipe canisters a week.
“It’s been a great run for these product lines and the demand continues to skyrocket,” said Pat Rusch, operations manager at Rockline’s Sheboygan plant, which also manufactures coffee filters. “We can sell every canister we can produce. At the same time, it’s been a tremendous challenge scaling our operations with that growth.” That means any increase in incremental capacity is well worth the return in revenue.
“An incremental 5% in throughput is an incremental 5% in capacity for us, which means an incremental 5% that we can sell,” said Frank Hacker, general manager at the plant.To capture those dollars, plant management embarked on a journey in 2006 to obtain real-time data essential to drive continuous improvement.
The challenge: A backward system
In 2006, the overall equipment effectiveness (OEE) for many of the manufacturing cells on the wet-wipe side of the plant was below 50%. Improving that number would require better visibility into how the lines and the individual machines were operating within in the five large work cells, which operate 24 hours a day.
Each manufacturing cell is dedicated to producing a specific size or type of wet wipe. The products vary in count and ingredients, including different sanitizing formulations and scents.
The high-speed packaging process begins with a “parent” roll of nonwoven fabric or substrate, which is automatically slit, perforated and wound into individual rolls of wipes. The rolls are placed into rigid plastic canisters and filled with liquid ingredients. The container lids go on next, then the labels. Finally, the canisters are packed in trays or cases and palletized for distribution.
Each manufacturing cell contains a series of machines and equipment strung together in series. Maintaining the right balance and speed on the line is critical for avoiding common bottlenecks such as a jam in a capper, labeler or filler that can disrupt the flow and trigger unplanned downtime.
Before 2006, each of these events would be manually captured. Whenever a machine went down or came back up, an operator would enter the time on a piece of paper, as well as line speeds and other parameters. Later, technicians had to key the handwritten metrics into an Excel spreadsheet, which was then shared with operators, managers and engineers in various plant departments.
“Our paper-based system for production reporting was very cumbersome when it came to trying to understand and analyze data,” Hacker said. Another problem was the system only looked backward. “We needed to understand our assets in real time. With that information, we also could look forward to see how we could fine-tune the process to increase throughput and reduce costs.”
Rusch added, “It became obvious that the only way to sustain growth was to find a tool or a set of tools that would allow us to consistently deliver year on year continuous improvement.
In search of a solution, the plant managers turned to Stone Technologies and Rockwell Automation. Rockline managers were impressed by the capabilities of the Rockwell Automation’s FactoryTalk Metrics software as a potential solution for monitoring its plant-floor equipment. The solution helps provide accurate, granular and specific information on machine production, performance and activities.
“Given that we were already using an Allen-Bradley control system, FactoryTalk Metrics was the ideal option as it would integrate seamlessly to the technology we already had in place,” Hacker said.
To convert that option into reality, Rockline put together a team consisting of its own engineering experts. They approached the project in systematic stages, starting with one cell and a scaled-down version of the software solution — meaning it collected a limited selection of data.
The pilot results far exceeded Rockline’s expectations. Managers had projected a six-month payback on the initial project, but got their return on investment (ROI) in three months.
“Within a couple of weeks of implementing the FactoryTalk Metrics solution, we saw an immediate 5% gain in OEE and throughput,” Hacker said. “That was enough to see the system was well worth the benefits. Just by being able to react and to respond to issues in real time, we were minimizing downtime and optimizing uptime.”
As Dan Engelhard, a Stone Technologies director, explained, “Previously, Rockline was catching big downtimes, but missing the micro stops. With the data analytics solution, Rockline could now understand those stops and how they were disrupting continuous flow.
The results justified moving the software into the other manufacturing cells. By that time, employees in other cells were clamoring for the new system.
Each cell underwent a “hard” transition, meaning the software replaced the manual data-collection system almost overnight. To bring operators up to speed on the computerized solution, training experts from Stone Technologies knew they needed to take an immersive approach.
“Cultural adoption of a new system can take a while in many companies,” Engelhard said. “Rockline, with our assistance, became aggressive in that arena. Operators weren’t allowed to use pencil, paper or clipboards after the system went live. We went straight to the screens.”
Employees can view the real-time status of the operation from any vantage point in the cell. Large panel displays in the center of each work center scroll data points at a steady rate. During scheduled or unplanned downtime, the displays become giant clocks that track the time required to return to normal operations.
“Seeing the numbers from the FactoryTalk solution motivates our operating teams and helps drive accountability,” Hacker said.
The system’s intuitive nature also eased the transition. “From an operator perspective, FactoryTalk Metrics are easy to read, easy to interface with and easy to get information out of,” Rusch said. “From engineering- management perspective, the data is instantly credible and critical for charting continuous improvement.”
Rockline improvement teams used the data to understand the crux of problems on the line. For example, the capper in one of the cells showed a significant amount of intermittent downtime, which triggered stops on the line. By analyzing production data, engineers identified the raw material (lid) as the root cause.
“We went to Stone Technologies and Rockwell Automation for help to cure our raw material issue,” Hacker said. “Data delivered from the solution showed the impact of the material on our process. We couldn’t do that before.”
Today, each manufacturing cell’s OEE exceeds 70%. “We went from mediocre to world-class,” Hacker said.
Canister production in each cell improved; Rockline saw the biggest increase on its cell with the highest demand, which increased output by more than 180,000 units a week.
“FactoryTalk Metrics allowed us to take advantage of all incremental capacity,” Hacker said. “Quality is also up because line operators can react to problems sooner.”
Rockline’s improvement teams are focusing on their next project using FactoryTalk data: reducing waste and scrap. They are also using Stone-generated information as an input for process simulation and modeling. By using live data, they can evaluate the impact of process changes or equipment upgrades on overall performance. This allows them to identify key opportunities and maximize future capital investment.
“The system will do the heavy lifting for us,” Hacker said. “And we expect similar results.”
Robbie Kerfoot is the client engagement manager Stone Technologies Inc.
Stone Technologies Inc. is a certified member of the Control System Integrators Association (CSIA).
Original content can be found at Control Engineering.