Another benefit is that when the o-ring is expanded, the housing can breath and allow warm air to exit.

When the shaft rotates the o-ring then expands dynamically eliminating friction between the o-ring and the seal components. Often, the seal may integrate an o-ring that prevents ingress of moist air when the shaft is static. Lubricant is also prevented from exiting the housing keeping leakage to a minimum. Additionally there are typically ports at the bottom of the seal to allow any contamination that has entered the labyrinth to then exit through these ports. The axial or face labyrinth created by the nesting of the rotor and stator makes it extremely difficult for any type of contamination to pass through the seal. This is an excerpt from a paper,' Bearing Maintenance Practices to Ensure Maximum Bearing Life' presented by Brian Dahmer of SKF USA at the 2013 International Pump Users Association. The rotor provides a flinger effect throwing contaminants off of the seal when it is rotating. Using nomenclature similar to that of motors, the rotating element is typically referred to as the rotor and the stationary element is typically called the stator. Labyrinth seals may come in a variety of forms but certainly some of the more common and effective are cartridge type labyrinth seals (often referred to as isolator type seals) that include a rotating element that is mounted on the shaft and a stationary element in the housing.

Bearing isolator seal india