Grease vs Oil Retention
|The viscosity of grease is much higher than oils and is much easier to retain. Therefore,
a non-spring loaded lip is both sufficient and cost effective for this application.If contamination is the primary control parameter, then the seal should be installed
in the opposite direction shown above. Below are some other design options used
for grease retention:
|The retention of oil is a more challenging task than grease because of the low viscosity
of oil. A spring is required to help maintain the proper radial load for sealing.
The spring is installed facing the fluid and hydrodynamic aids are sometimes molded
to the air side angle to assist in the sealing action. Below are some other design
options used for oil retention.