There is less than a 5 percent difference in the cumulative
particle counts obtained at each corresponding 2 minute
inteval in each size range.
The particle counts obtained for a given size from each sample
do n&-deviate more than 10 percent from the average particle
counts of that size from all samples.
Each recorded cumulative particle counts per mL is within the
range specified as follows:
Number of particles
22.214.171.124 Contaminant injection circuit validation.
Validate the contami-
nant injection circuit at the maximum gravimetric level to be used (see 126.96.36.199).
Acid the required quantity of ACFTD to the injection circuit fluid.
samples after 30, 60, 90, and 120 minutes at the point of injection into the
element test circuit. To obtain these samples, fully open valve and collect
at least 200 mL in a sample bottle.
Return this fluid to the injection reservoir
Then without closing the sample valve, collect the sample for analysis. Analyze
samples gravimetrically in accordance with SAE ARP 785. The gravimetric level
of each sample shall be within 10 percent of the average of the four samples for
the validation of the test stand.
188.8.131.52 Test preparation.
Adjust the fluid volume of the filter test
circuit to the required volume.
Calculate and prepare the required amount of
test contaminant and adjust the fluid volume of the contaminant injection cir-
cuit (see 184.108.40.206).
Install the empty filter test housing in the element test
Circulate the fluid in both circuits through the cleanup filter
assembly until the required cleanliness levels are attained (see 4.7 4.3 and
4,7.4.4), as indicated by the automatic particle counters.
Bypass the cleanup
filter assembly and record the pressure drop of the empty test housing at rated
flow and stabilize test conditions.
Add the required contaminant (see 4.7.4,7)
to the injection system and recirculate for 20 minutes to thoroughly disperse
The test method shall be as follows.
The pre-filter element under test shall be installed in the
housing (with bypass valve sealed).
The pump shall be started, and rated flow attained by adjusting
the variable speed drive. The cleanup filter assembly shall be
bypassed during the entire test.
Measure and record the clean
assembly pressure drop.
Calculate and record the clean element
pressure drop, which is equal to the clean assembly pressure
drop minus the housing pressure drop measured in 4.7,4.11.
Open the sampling valves and start recording particle counts on
the automatic particle counter. Particle counters shall be
consistent with 220.127.116.11.
Start flow from contaminant injection system to the filter test
Measure and record
Maintain a flow rate of 0.5 L/min.
the flow rate. Open valve B and adjust flow so that the total
fluid discarded is 0.5 L/min which equals the injection rate.