MIL-DTL-85052B
touching the center clamp (see figure 1). A second output measuring accelerometer shall be
mounted on the test mandrel adjacent to but not touching the center clamp (see figure 1). The
test assembly shall be subjected to simple harmonic motion having a vibratory input of 2g. The
input acceleration shall sweep through a frequency range of 50 to 500 to 50 Hz. The sweep rate
shall be logarithmic, requiring 5 minutes/cycle. One frequency cycle shall consist of 50 to 500 to
50 Hz. A resonance search shall be made and each resonance recorded (frequency and
acceleration peak).
4.4.4.2.2 Transmissibility. Transmissibility Ratio (TR = g output/g input) shall be
calculated for each resonance peak and recorded. The clamps shall then be dwelled at the
most severe resonance peak for 30 minutes at a constant sinusoidal vibratory input of 10g as
measured at the input accelerometer. All clamps shall meet the requirements specified herein
(see 3.5.3.2). The vibration test shall be repeated with 3 new clamps of the same size as
specified. Upon completion of vibration test, each clamp shall be subjected to the diametral
retention test as specified herein (see 4.4.4.1).
4.4.4.3 Ozone resistance test for qualification. When specified on the applicable
specification sheet, fifteen test samples of size -2 shall be separated into 3 sets of five. Each
set of five shall be assembled with appropriate fasteners around 0.125 + 0.001 diameter steel
mandrels. The first set shall be exposed to ultraviolet light as specified in 4.4.4.3.1. The
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second set shall be conditioned for 70 hours at 212 F. The third set shall not be subject to any
preconditioning prior to the ozone test. The three mandrels with the five clamps each shall be
immersed in an ozone environment of 600 parts per hundred million (PPHM) concentration for
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6 hours at 125 F. Clamps shall meet the requirements specified herein (see 3.5.3.3).
4.4.4.3.1 Ultraviolet exposure. The sample shall be exposed to ultraviolet (UV) light in
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accordance with ASTM-G154 without water exposure for 72 hours at 125 F. The ultraviolet
light source shall be UVA-340 lamps as specified in ASTM-G154. See 6.3 for recommended
UV exposure equipment.
4.4.4.3.2 Ozone resistance test for conformance inspection only. The ozone resistance
test conducted for qualification inspection (see 4.4.4.3) shall be conducted for the conformance
test. When cushions larger than size -2 are being tested, the larger cushions shall be cut to
length and assembled on a size -2 band for mounting on the mandrel.
4.4.4.4 Thermal shock test. Five test-clamps of size -16 shall be mounted on a test
mandrel conforming to 4.4.1.2. The mandrel with clamps installed shall be exposed to 5
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cycles of 30 minutes exposure at -65 F, 15 minutes rest at room temperature, followed by 30
minutes exposure at the maximum rated service temperature (see applicable specification
sheet). Clamps shall meet the requirements specified herein (see 3.5.3.4).
5. PACKAGING
5.1 Packaging. For acquisition purposes, the packaging requirements shall be as
specified in the contract or order (see 6.2). When packaging of the materiel is to be performed
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