From a task point of view, assembling diesel engines at Cummins Engine Co. (Columbus, IN) hasn't changed all that much over time. The engines travel down a rather traditional assembly line. At the end of the line, the engines go directly to test. This happens about 160 times a day, and the work—the actual assembly—is highly labor intensive. There is little that can be cost-effectively automated to affect product quality.
What has changed (and in some ways it's been dramatic, or traumatic, depending upon how one perceives change) is the way the assembly process is managed.
What's in place on the floor now (and has been mandated in the language of the union's latest long-term contract) are high-performance teams. "The idea here," according to Cal Latting, quality manager, Assembly and Test, "is to achieve a higher level of quality by giving individuals in the teams greater responsibility and involvement for what they do and how they do it. We expect them to participate in making decisions that will change the process and ultimately improve product quality."
The teams, Latting suggests, constantly monitor the performance of all of the assembly processes. However, specific kaizen teams are put together to address special areas that have proven difficult—a bottleneck in the line, for example. "We've been through participative management," Latting says. "And then quality circles. Now we're using high-performance assembly teams and kaizen for special problems—which may look at everything from the logistics and flow of the line, to the location of materials, to the relationship between the orientation of the engine, the materials, and the operator. If we can eliminate even a few physical steps or motions, we've made an improvement. Which helps us reach for higher and higher quality."
But they're not expected to do all this without proper preparation. The business goals of the company, including financial and market share information, and, most important, a stream of constant feedback from internal customers and from OEM final customers alike, flow constantly to the teams and prepare them to execute, in a self-directed fashion, what's needed to improve performance and product quality goals.
And what might those goals be? Right now, says Latting, engines going through internal inspection have a less than 0.5 rph (repair per hundred) "nonconformance" rate. The goal, of course, is 100% perfect quality. But working toward that goal, in the form of a next step, is getting to a level in the repair per million range.
A final question when considering quality and the engine assembly process: Isn't much of the quality determined upstream from assembly, in concept and design engineering? Yes. In fact, Latting says that not too long ago, the ability to improve the quality of an engine at the point of assembly was highly unlikely. But that's all changed today. "Members from our teams," he says, "are involved from the beginning, in the earliest stages, including the design phase, where positive quality changes can be made. The single-most important quality tool is communication at all levels. Listening to everyone's opinion and coming forward with ideas for change, for improvement.
"Total work force involvement and communication are the keys to quality."