equipment until replacement is required. Upon
internal filters, the 3-micron elements in particular.
completion of periodic maintenance, hydraulic SE is
You begin by operating the contaminated SE so
certified as having a fluid contamination level not in
maximum circulation of fluid through the equipment
excess of Navy Standard Class 3.
reservoir and internal 3-micron filters occurs.
Maintain the flow long enough to allow a total flow
Fluid Sampling
equivalent to at least five times the total fluid capacity
of the equipment reservoir. Monitor all filter
Fluid sampling points and procedures vary with
d i ff e r e n t i a l - p r e s s u r e i n d i c a t o r s t h r o u g h o u t t h e
the SE type and model. For specific procedures
operation. If elements appear to be loaded, check and
applicable to the particular equipment, you should
replace them.
refer to NAVAIR 01-1A-17. Run the SE for a minimum
You should resample and analyze the fluid from
of 5 minutes before you take a sample. This results in
the reservoir. If improvement is shown, but the
fluid flow through SE reservoirs, which ensures a
contamination level is still excessive, repeat the
uniform distribution of contaminants. On some SE
process. If there is still no improvement, try to find the
models, you need the return pressure outlet to the
internal contamination source, such as a failed
reservoir fill opening to achieve such a flow. Find and
component. Replace any components you determine
gain access to the reservoir drain valve and other
to be contaminating the fluid, and continue
sampling points and adapters. You need to remove dirt
decontamination by draining, flushing, and refilling
and other visible contaminants from the exposed part
the equipment with new filtered fluid. Recirculation
of the drain valve and /or sampling adapter. When
clean and resample, as before, to determine
taking a sample for a patch or particulate patch test,
acceptability. When you find the fluid samples from
wipe the valve or adapter with a clean, disposable
t h e r e s e r vo i r t o b e w i t h i n a c c e p t a b l e l i m i t s ,
cloth. The use the plastic wash bottle in the
recirculation cleaning may be terminated.
Contamination Analysis Kit 571414 to flush the
fittings with clean MIL-PRF-680.
PURIFYING.--Purification is the process of
removing air, water, solid particles, and solvents from
When you have finished flushing the fittings, open
hydraulic fluids. A schematic of a typical
the reservoir drain valve and allow approximately 1
commercially available purifier, P/N AD-A352-8Y17,
quart of fluid into a waste receptacle. Without
P/N PE-00440-1H or equivalent, is illustrated in figure
interrupting the flow of fluid, take the required sample
9-12. Contaminated fluid going to the purifier tower is
by letting an additional 4 ounces of fluid flow into a
first filtered by a 25-micron (absolute) filter. The
clean sample bottle (provided with the contamination
vacuum applied to the tower removes air and water
analysis kit). Close the drain valve after you remove
from the contaminated fluid. As the fluid comes out of
the sample bottle from the fluid stream. Label the
the tower, it is filtered through a 3-micron (absolute)
bottle to indicate where you took the sample. Repeat
filter to remove solid particles. This cycle is repeated
the sample-taking procedure at other specific or
until a desired level of cleanliness is attained. For
available sampling points, collecting each sample in a
support equipment contaminated with air and water,
separate bottle. Visually inspect the fluid collected in
the use of a purifier to clean the equipment will reduce
the waste receptacle for free water. If free water is
the consumption of oil and replace the need for
seen, decontaminate the system according to
flushing.
applicable procedures.
FLUSHING.--Flushing is used to decontaminate
Decontamination
support equipment that is heavily contaminated with
Decontamination of unacceptable SE equipment is
particulate matter, or when the fluid contains a
performed by recirculation cleaning, purifying,
substance not readily removed by the internal filters.
flushing, or purging, as required; these actions are
To begin the flushing procedure, you drain, flush, and
performed by the supporting activity.
reservice the equipment reservoir using new filtered
fluid. If the contamination originated at the pump,
RECIRCULATION CLEANING.-- Recircu-
drain and flush the hoses and lines directly associated
lation cleaning is used when equipment is
with the pump output separately.
unacceptably contaminated with particulate matter (in
Operate the equipment so fluid flows through all
excess of Navy Standard Class 3), but the fluid is
circuits. Allow output (or return line) fluid to dump
otherwise considered satisfactory. In recirculation
overboard into a waste receptacle. Continue flushing
cleaning, the equipment is self-cleaned using its
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