Page 12 - Parker - The Handbook of Hydraulic Filtration
P. 12
Contamination Types and Sources
Filtration Fact Prevention
Excessive water can usually be into standard filter housings and are
Free water is heavier than removed from a system. The same pre- generally used when small volumes of
ventative measures taken to minimize water are involved.
oil, thus it will settle to the
particulate contamination ingression
bottom of the reservoir Centrifugation
in a system can be applied to water
where much of it can be contamination. However, once exces- Separates water from oil by a spinning
sive water is detected, it can usually motion. This method is also only
easily removed by opening
be eliminated by one of the following effective with free water, but for larger
the drain valve. volumes.
methods:
Filtration Fact Absorption Vacuum Dehydration
Separates water from oil through a
This is accomplished by filter elements
vacuum and drying process. This
that are designed specifically to take
Absorption filter elements
out free water. They usually consist of a method is also for larger volumes of
have optimum water, but is effective with both the
laminant-type material that transforms
performance in low free water into a gel that is trapped free and dissolved states.
within the element. These elements fit
flow and low viscosity
applications.
Vacuum dehydration system
10
