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MIL-A-85802(AS)
Example:
Given: Total number of cycles per axis required: 540,000 cycles
Number of resonant frequencies determined per axis: 2,
1.200 Hz
2.500 Hz
Calculated:
Number of cycles per resonant point: 540,000 = 270,000 cycles.
2
Test time at 200 Hz: 270,000 cycles
= 22.5 minutes
200 Hz x 60 sec/min
Test time at 500 Hz: 270,000 cycles
= 9.0 minutes
500 Hz x 60 sec/min
Total test time = 31.5 minutes
4.6.11 Service life. The actuator shall be subjected to 5,000 cycles of
operation. The actuator shall be mounted as indicated by the applicable
drawing. The firing circuit shall be energized once for each cycle to
activate the actuator. The duty cycle for the actuator shall be 20% on and
80% off (see 3.3.10.1).  After every 500 cycles, the actuator shall be
subjected to the test of 4.6.2.3. The last 1,000 cycles shall be conducted
with the actuator plunger striking the lever of a test fixture which offers a
20 pounds resistance. The fixture shall be designed so that the actuator
plunger shall contact the 20 pound load after it moves 1/16 inch. The
actuator shall be subjected to the test of 4.6.2.3 after the completion of
5,000 cycles.
4.6.12 Shock.
4.6.12.1 Shock pulses. The actuator shall be subjected to the shock pulses
in each of the three mutually perpendicular axes, not in any specific order.
The test parameter tolerances shall be as follows: acceleration: 10%,
pulse duration: 1 millisecond. The actuator shall be mounted to the shock
table by means of a rigid fixture utilizing the mounting area as indicated by
the applicable drawing. The control accelerometer shall be mounted on the
test fixture, adjacent to the mounting area of the actuator. Inadvertent
activation of the actuator plunger, failure of the actuator to function, or
structural damage to the actuator shall be cause for rejection.
4.6.12.2 Test. The actuator, in the cocked position, shall be subjected to
two half-sine shock pulses in each axis. The acceleration level shall be 125
g's with a pulse duration of 11 milliseconds.
4.6.13 Post test.
4.6.13.1 Salt fog, internal. All of the internal surfaces and internal parts
shall be subjected to salt fog tests, while assembled, In accordance with
MIL-STD-81O, Method 509.2, Procedure I. The exposure time shall be 24 hours.
At the completion of the test exposure, all parts shall be inspected for
corrosion. Any evidence of corrosion shall be cause for rejection,
10

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