Page 34 - Parker - The Handbook of Hydraulic Filtration
P. 34
Fluid Analysis
Filtration Fact ▼ Patch Test
▼ Portable Particle Counter content, and compared to known ISO
The only way to know the ▼ Laboratory Analysis standards. By using this comparison,
the user can get a “go, no-go” estimate
condition of a fluid is of a system’s cleanliness level.
Fluid analysis is an essential part of
through fluid analysis.
any maintenance program. Fluid analy-
Visual examination is not sis ensures that the fluid conforms to Another lesser-used deviation of the
patch test would be the actual count-
an accurate method. manufacturer specifications, verifies ing of the particles seen under the
the composition of the fluid, and deter-
microscope. These numbers would
mines its overall contamination level.
Filtration Fact then be extrapolated into an ISO
Patch Test cleanliness level.
Any fluid analysis should A patch test is nothing more than
The margin of error for both of these
always include a particle a visual analysis of a fluid sample. It
methods is relatively high due to the
usually involves taking a fluid sample
count and corresponding human factor.
and passing it through a fine media
ISO code. “patch”. The patch is then analyzed
under a microscope for both color and
Fluid Analysis Methods
Typical test kit
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