2025 IndustryWeek Best Plants: Freudenberg-NOK Santa Ana Leads with Lean

At the plant, uncured rubber is closely inspected before entering inventory, then prepared for molding. The plant makes the gaskets in compression or injection molds. Depending on the specific demands of the product, including size and material, the molded parts are sometimes trimmed by hand, or de-flashed cryogenically — flash-frozen, with excess parts cleanly snapped off after. Finished rings are inspected, packaged, and shipped.

Each step of the process is awash with visual cues, labels, and other poka-yoke error prevention methods. In the above process, raw material for gaskets is stored in blue bins; newly-formed gaskets would go in yellow boxes; scrap cut or de-flashed from them would go into red boxes, and finished gaskets would go into green bins.

While FNOK does have a wide variety of gaskets with interesting shapes, it’s also true that many gaskets are simple, round, black, rubber O-rings. This produces its own kind of quality control problem: When your parts are as small and indistinct as a black, 10-mm rubber O-ring, processes are necessary to keep them from being mixed up with black, 11-mm rubber O-ring. The solution was developed by an engineer at the plant: Add a to-scale watermark of each O-ring to the digital or paper order attached to it. If a gasket’s place in an order was in doubt, one can simply call up the work order on a horizontal screen and drop the ring onto it for a quick visual comparison.

Full-team lean

Instrumental for lean principles is respect for employees autonomy, and FNOK marked a striking version of employee autonomy in action.

While touring the site, I noticed labels indicating the proper placement of tools and machines everywhere. The plant floor, of course, but also the testing labs, the quality control area, the offices, and even the bathrooms and cafeteria had labels and tape to set out where things were meant to go. While on the floor, Amann showed me the label station, which workers were always free to access, and which was refilled whenever necessary. The ubiquity of the labels struck me as a unifying feature of the factory, so that wherever one worked, one would always know where things went.

Later, in the quality-control room, I noticed another example of continuous improvement at work: Knitting needles. Specifically, jars of them on the desks of the quality-control department. It turned out that knitting needles, which come in a variety of colors and materials as well as standardized sizes, were perfectly suited for precisely manipulating and closely examining rubber gaskets, an innovation discovered by one of the quality control employees there. It quickly caught on.

Floor worker autonomy isn’t limited to labels and knitting needles, either. FNOK employee work teams are enabled to work on production scheduling, skills certification, safety and environmental compliance, quality assurance, daily job assignments, performance reviews, training, hiring, and materials management. Vacation spending is done in work teams on a first-come, first-served basis, and team leads even weigh in on disciplinary actions and terminations.

And in exchange for its employees’ investment, FNOK invests in its employees. The plant offers gain-sharing rewards for individual performance, rewards for team performance, profit-sharing, and paid knowledge and skills training — including, of course, lean management system training.

According to Amann, this is consistent with the plant’s perspective on leadership. “Leadership, for us, doesn’t mean that just the management team is supposed to lead,” he said. "Leadership is also expected to come from all levels of the organization."