What are the common gear oil filtration processes?

Common processes include:

Depth Filtration: Trapping particles within the filter media.
Surface Filtration: Capturing particles on the filter surface.
Centrifugal Separation: Using centrifugal force to separate contaminants.
Vacuum Dehydration: Removing water and gases under vacuum conditions.
Magnetic Filtration: Extracting ferrous particles with magnets.
Coalescence: Combining small water droplets for easier removal.
These processes target specific types of contaminants.