Mike Grammel, plant manager at Chardon Rubber Co., knew it took too long to changeover dies between customer batches-regularly up to 45 minutes. That meant lengthy downtime for Chardon Rubber’s machines. And when its machines aren’t running, Chardon Rubber isn’t making money.
Grammel didn’t know how to make the plant more efficient without a substantial cash infusion.
Six months ago, he invited the Work In Northeast Ohio Council to use his plant as a host site for a hands-on manufacturing process-improvement seminar.
“We knew we had to improve the time,” says Grammel, “but we also wanted a system that was proven and standardized.”
WINOC’s class spent the day observing Chardon Rubber’s processes, before giving Grammel a report detailing its assessments.
WINOC suggested SMED-single-minute exchange of dies. In early June, Grammel trained plant employees in the process. They then videotaped one production line-a continuous batch line handling the entire manufacturing process from cutting raw materials to packaging-and saw several ways to fine-tune the work flow.
Here’s how they slashed time on the production line:
- Improving the availability of materials.
Large, stackable containers of the raw rubber strips were brought closer to the production line making them more accessible. Before this, boxes were stored in a separate room, sometimes behind other boxes and high up on shelves.
- Increasing activity while machine is operating.
Tool carts were brought to the production line while the machine was operating. Previously, production-line employees waited until the machine was shut down before retrieving new tools and dies and often retrieved them one tool at a time from across the room. Mike Leone, the plant’s industrial engineer, explains, “We try to do more things while the machines are still running.”
- Purchasing an additional die.
One task that slowed the production line was that workers had to clean the single tool and die before replacing it on the machine and running the next product batch. For $500, Chardon Rubber bought a duplicate die. Now workers replace the die, start the machine, then clean the one that was removed. That move alone shaved 14 minutes off the changeover time.
- Creating a task checklist.
Two lists of jobs were determined-external and internal. The external list handles tasks that must be completed before the machine can be shut down. The internal checklist provides an ordered list of jobs to follow to get the machine up and running.
- Charting progress.
Grammel says the pilot program has resulted in a 60 percent reduction in changeover time-down to an average time of 18 minutes. He’s also posted a chart at the end of the production line. After each changeover, the total time is recorded, along with any notes. “We’re looking for any patterns,” says Grammel. “And other ways to cut time. Our goal is a single-minute changeover-under 10 minutes.”
That’s the benefit of observing production lines in action, says WINOC’s Fletcher Birmingham. “A good observation, followed by improvements, can usually cut your changeover time in half without spending a significant amount of money,” he says.
For Chardon Rubber, it’s been even better. It’s resulted in less material waste because smaller batch sizes can be produced, and a shorter lead time for customers. That means Chardon Rubber can fill its customers’ orders faster and supply rubber products to more customers at a lower cost without adding manpower or machines to the plant.
Grammel says he expects to institute the quick changeover method on the rest of Chardon Rubber’s production lines early next year.
