The use of composite bearing films in a water-conditioning valve let engineers switch valve materials from brass to 20%-glass-filled, modified PPO resin. The change lowered material costs and cut the number of secondary manufacturing operations.

Glass-filled PPO maintains dimensional tolerance of the valve body and rotator valve. But initial tests showed that plastic-to-plastic friction caused excessive wear and " slipstick," a condition of erratic opening and closing motion.

The fix: a nanocomposite material applied to the rotating valve exterior (after a proprietary pretreatment process) to a thickness of 0.0007 to 0.0011 in. per side. The composite is cured at a low temperature that doesn't distort intricate valve surfaces. It withstands the harsh water environment, lowers valve-actuation torque, and lubricates the rotator valve for life.

Dimension Bond, 773-282-9900,