Polymer Labyrinth Seal (PLS)

The Chesterton patented Polymer Labyrinth Seal (PLS) is a non‑contact bearing seal designed to provide protection for pumps, gearboxes, and other rotating equipment in splash applications. The unique design minimizes fretting caused by conventional lip seals and helps increase bearing and gearbox life by extending the mean time between equipment repairs (MTBR).

This unitized labyrinth seal uses Chesterton’s exclusive polymer to create a non‑contacting three‑piece seal design that includes a rotor, a stator, and a built‑in valve with no wearing parts. During operation, centrifugal force and gravity enable the lubricant to be contained within the labyrinth and flow back into the bearing housing, while outside contaminants are excluded and redirected back to the atmosphere.

The unique design also incorporates a built‑in valve activated by shaft rotation, which engages during shutdown periods to create a positive seal during idle time and block the ingress of external contaminants from entering the housing.

Chesterton’s material technology is manufactured from an advanced, durable, maintenance‑friendly thermoset polymer compatible with common bearing and gear oils and offers a cost‑effective alternative to other material options. Each seal is custom manufactured to the exact equipment size needed to maximize performance.