Little Things Mean A Lot
A global consumer goods manufacturer was experiencing high levels of downtime, jams, and long changeovers on a critical production line. They invited Process Improvement Partners to their plant to observe and discuss the problem and identify opportunities for improvement. After reviewing performance, we took a walk to the line. The line was running, and after a description of line components, it became apparent there were quick opportunities to improve performance of the line. The techniques we would use were quite basic: leveling, squaring, aligning, and centering of products with the process. It seemed so simple, and the customers were skeptical. We suggested a five-day Kaizen to improve line reliability, scheduled for January 2019.
Leading up to the Kaizen event, we had many discussions with line operators, mechanics, and engineers, and we made several confirming observations on the line. During a discussion with the Plant Manager, it became apparent he didn’t buy-in to the approach. He had used a process called “Center Lining” before, and had mixed results. In addition, it took weeks to accomplish. We assured him centering of the process would be completed on the first day of the Kaizen and then we would optimize all parts of the process around the center in the following days. He was still skeptical, but heard enough and saw our confidence, and gave final approval for the Kaizen to proceed.
In most Kaizen events, we provide a structure and approach to the team charged with solving a problem. We very rarely dictate specific actions to the team. In this case, the entire first day was controlled and team members were asked to follow very specific instructions before implementing their ideas.
After receiving training on the approach, the team walked to the production line. We reviewed safety requirements, shut down the line, and locked it out. The next step was to identify the center of the critical packaging process. This was the part of the line where everything comes together – the product and the package. We told the team everything leading up to the packaging process should be located and optimized to the center of the process. They didn’t think it would be very important, but were willing to learn and find the center of the line.
We located the center of the line at the midpoint of the conveyor frame on the out-feed side of the equipment and wrapped a string around that point. Then, stretching the string through the equipment, we found the center of the conveyors leading up to the equipment. A trained eye can keep the center precise within 1/32”, so we found what we believed to be center along approximately 100 feet of equipment and conveyor and pulled the string taut. Then, we marked the equipment and conveyor every 4 feet along its length to identify center for the process. Once complete, we noticed all product was coming into the equipment off center. The packaging was tracking off-center as well. That was the first time the skeptical team members saw something they weren’t expecting.
Our next step was to check the levelness of all of the conveyors leading up to and through the equipment. Ideally, all conveyors should be no more than 1/32” out of level at every transition (one section of conveyor to the next section) and side to side. Using a torpedo level and some shims, the team documented levelness of every section of conveyor. They found many of the conveyors were out of level by more than ¼” and some were out as much as ½”. The good news was this condition was easily corrected, and by the end of two hours, all conveyors were leveled throughout the process. The team was losing its skepticism as the products ran more consistently once we started the line back up. The first day ended with the team handing the line back over to the production organization.
The next morning, the team came in energized. They heard from the afternoon shift and overnight shift that the line had run smoothly overnight - much better than anyone had expected. We had four more days to improve things before the end of the Kaizen.
The next step was to optimize the location of the product with reference to the center of the process. Now that we had identified the center and leveled the line, this was easy. The challenge was to determine ways to ensure that our new settings would not change as soon as the Kaizen was over. The team was given the freedom to come up with ways to create and sustain the new settings. Using collars, pins, and labels, the team came up with ways to identify the proper locations for all of the different products running on the line. They also identified the product changeover steps (in the order to be followed) and labeled each part of the line with changeover steps that would need to be accomplished in proper sequence. These labels were made with large, bright green stock, so people wouldn’t miss them and forget a changeover step.
One problem the team identified was that the packaging wasn’t wrapping the product in a consistent manner. Upon further investigation, it was determined a top guiding roller was applying unequal pressure to the corrugated wrapper and the wrapper was shifting from side to side. One of the team members came up with a simple solution - tie all parts of the top guiding roller together to guarantee equal pressure across the wrapper. By doing this, the wrapper consistently met the product every time.
Improvements came fast and furious over the final days of the Kaizen, and by the last day, everyone noticed a significant improvement in line performance. The operators on the line thanked the team for correcting years of problems and even offered suggestions to make things better, which the team was able to incorporate into their work.
At the report out, team members remarked they were surprised how extremely small improvements impacted performance. They also realized these techniques could be taken to any other line in the factory. Once skeptics, they become zealots.