Freudenberg-NOK has a 20-year history of employing lean principles to drive continuous improvement across the enterprise. Growtth (Get Rid of Waste Through Team Harmony) is the manufacturer's continuous-improvement program, and it adopts concepts of the Toyota Production System, including the pursuit of single-piece flow.
Given the company's history with lean, it may come as no surprise that Freudenberg-NOK Sealing Technologies has taken the idea of single-piece flow to its molding presses. While many of its molding presses are of the traditional variety – meaning large, heavy pieces of equipment that produce batches of components from multiple cavities -- Freudenberg-NOK has begun introducing to its manufacturing facilities a smaller, more nimble single-cavity press that produces seals one at a time.
The impetus for this technical evolution? Better quality and material savings are two drivers, says Theodore Duclos, vice president and general manager of the Global Fluid Power Division of Freudenberg-NOK Sealing Technologies.
With the single-cavity molding, "we are able to make better parts more consistently," Duclos says. That's because the new production operation allows for better control of such variables as temperature and pressure. Better quality up front means fewer man hours and machining required on the back end in trimming operations, and less waste material to address.
"The less operations you need to perform, the better," he says.
Employing lean, Freudenberg-NOK has squeezed significant waste out of manufacturing operations over the years, but those improvements have not been addressed on the technical side. "We asked, ‘How do we bring the technical aspect into this," Duclos says.
Making Single-Cavity Molding Work
Make no mistake, single-cavity molding is not merely a shrunk-down version of multicavity molding. Duclos says the company had to develop its own tooling concepts, machine concepts and materials to make single-cavity molding work in a way that made financial sense, plus kept customers happy.
The customers took some convincing, he said, because – at least on the surface -- it seems apparent that producing in batches versus one-by-one would be less expensive, not to mention faster. But convinced they were. And while Duclos wouldn't divulge any specifics, he says the cycle time for the single-cavity molding process has been reduced compared to multi-cavity molding.
Developing single-cavity molding also required putting together a team with diverse knowledge, he said. In this case, the team included engineering, production and financial personnel. Duclos clearly is pleased with the team's output. Not only has single-cavity molding improved quality, but he says it also has resulted in less complex and more flexible machinery, and shorter product development cycles.
"We have had excellent product launches," he adds.
Duclos says Freudenberg-NOK Sealing Technologies began working on the single-cavity molding process six or seven years ago, a time frame that speaks to the technical and financial challenges that needed to be met. The company then introduced single-cavity molding two or three years ago in pilot projects and has more recently begun phasing it in on a bigger scale.