 |
|||
|
|
|||
| ||||||||||
|
|  MIL-F-24666(SH)
Criteria for acceptance.
4.7.5.2
The criteria for acceptance shall be as
follows:
(a)
There shall be no evidence of structural, seal, or filter medium
failure.
There shall be no decrease in slope of the pressure drop versus
(b)
contaminant added curve.
The performance requirements of table II shall be satisfied.
(c)
4.7.6 Pressure buildup.
The test shall be conducted on element no. 2
at rated flow of the element.
A typical test circuit is shown on figure 5.
4.7.6.1
Test procedure.
The test procedure shall be as follows:
The test fluid used in the system shall be pre-cleaned as
(a)
specified in 4.3.1.1. The cleanup filter assembly must be
bypassed during testing.
(b)
The pre-filter element under test shall be installed in the
test housing.
The pump shall be started, valves A and B opened, and rated
(c)
flow attained by adjusting the varidrive. The differential
pressure drop across the element shall not exceed 4.0
differential.
Standardize ACFTD shall be added through the dust valve H in
(d)
Increments of 6 grams at 4-minute intervals. Two minutes after
each test dust addition, pressure differential flow and temper-
ature shall be recorded. The differential pressure across the
element shall not exceed 30
The pump shall not be
stopped during the test.
A curve showing differential pressure across the element versus
(e)
cumulative weight added in grams of standardized ACFTD shall
be included in the test report.
4.7.7 Flow fatigue. The pre-filter element shall be installed in the test
housing and shall be subjected to pressure-flow cycles at flow rates specified in
4.7.7.1. A cycle shall consist of increasing the differential pressure across
the filter element from zero to the maximum specified and back to zero by first
increasing, then decreasing, the flow through the test element, which has been
loaded with the minimum amount of ACFTD necessary to achieve the required
differential pressures.
4.7.7.1 The cycling rate shall not exceed 300 cycles per minute. The
number of cycles and test flow cycles at each differential pressure shall be as
follows:
Number of cycles at
differential
Flow ranges (gal/min)
90,000
cycles
at 10
15
-
50
50
-
100
8,000
cycles
at 15
50
-
100
2,000
cycles
at 20
500
cycles
at 30
50
-
100
50
-
100
100
cycles
at 120
|
|
Privacy Statement - Press Release - Copyright Information. - Contact Us |
Click
here for thousands of PDF manuals