from the sample bottle and pour exactly 100 milliliters
bottle. Allowing the fluid sample to remain motionless
of fluid into the graduate. Discard any remaining fluid.
for 10 minutes or longer may make it easier to see
Pour the contents of the graduate into the funnel, on top
visible droplets, if water is present. If fluid samples are
of the previously introduced filtered solvent. Allow the
hazy or pink, water may be present. Another identical
contents of the graduate to drain completely into the
sample bottle filled with a standard of unused fluid can
funnel. Use the filtered solvent to wash down the inside
be used for comparison. If water is observed, take
surface of the graduate until it contains approximately
another sample from the system to verify the indication
100 milliliters of solvent.
before rejecting the system under test.
Operate the syringe by slowly pumping it, which
Before you can process a sample, get the
draws a vacuum, until sustained filtration of the fluid is
equipment ready. Remove the filter holder assembly
indicated by a steady drop of the fluid level in the
from its storage position in the kit. The funnel and
funnel. When the fluid level in the funnel drops enough
holder support are assembled and stored in an inverted
to allow addition of approximately 50 milliliters of
position in the vacuum flask. To prepare the funnel and
solvent, pour half of the contents of the graduate into
holder support for use, remove them from the vacuum
the funnel as filtration continues. If necessary, operate
flask, invert them, and reinstall them in the vacuum
the syringe again to maintain sufficient vacuum for
flask. If it is difficult to remove the holder support from
filtration. Carefully watch the filtration process in the
the vacuum flask, insert the back end of forceps into the
funnel, and note the decreasing fluid level. When the
slot (present on some holder supports) and pry the
fluid level drops to the narrow neck of the funnel, pour
holder support from the vacuum flask.
the remaining contents of the graduate into the funnel.
You should use the tube and adapter to connect the
syringe to the small opening located on the side of the
NOTE: Pour the contents so they flow down the
holder support. Wash down the inside wall of the funnel
inside of the funnel, making sure that the solvent is not
poured directly onto the test filter.
present. Make sure that the holder support screen, now
When filtration is complete, inspect the test filter
located at bottom of funnel neck, is also cleaned with
surface. If the central area shows a pinkish color, it
indicates that the test filter still has a residue of
hydraulic fluid. Direct a stream of filtered solvent
against the walls of the funnel until fluid reaches the top
of the tapered portion. Operate the syringe again to
on the funnel surface. The moisture can cause
initiate filtration and allow all of this fluid to pass
inaccurate indications of free water in the sample under
through the test filter. If free water is indicated, test to
see if the water originated from the hydraulic fluid
surface. If condensation is present, move equipment to
sample and not from the rinsing solvent. Perform an
an air-conditioned workspace.
additional analysis, but omit the solvent rinses. Water,
Remove the funnel from the holder support by
if present, will still appear on the surface of the filter
rotating the outer knurled ring in a counterclockwise
membrane, but will now tend to spread out rather than
direction until it disengages, and lift it upwards. Use
to appear in discrete droplet form. Examine closely.
forceps to carefully remove a single 47-mm test filter,
and place it on top of the screen of the holder support.
NOTE: When dry-cleaning solvent is used as the
Make sure that the blue separator discs are not installed
filtered solvent, the filter must be dried thoroughly prior
with the test filter. Reinstall the funnel on the holder
to being placed in petri slide. The solvent or fumes will
support, and secure it by rotating the outer knurled ring
craze and cloud the polystyrene petri slides.
in a clockwise direction until it is fully seated. Use
Test Filter Analysis
filtered solvent to repeatedly rinse the inside of the
After you process the fluid sample, visually
any residual solvent. Measure out approximately 15
milliliters of the filtered solvent, using the cleaned
graduate, and pour the solvent into the funnel to
level, compare the shade and color of the test patch with
"pre-wet" the filter membrane.
Shake the bottle of sample fluid. This action
standards. If the test patch displays a rust or tan color,
distributes the particulate content. Remove the cap
use the tan standard patch. If the test patch is gray, use