MIL-DTL-49055F
TABLE IX. Test fluids and test temperatures.
Test fluid
Test temperature °C
1/
20 to 22
MIL-DTL-5624 (JP-4)
1/
68 to 72
1/ Not for use with polyvinylchloride insulation.
Upon removal from the fluids, the specimen shall be free of surface fluids and shall remain for one hour in
free air at room temperature. Each specimen shall be weighed and compared with its initial weight. The
specimen then shall be folded and unfolded twice in accordance with 4.6.10 and then subjected to the
dielectric withstanding voltage test (see 4.6.4).
4.6.17 Durability of identification. The durability of product identification shall be evaluated at room
temperature as follows:
a. Test apparatus. A repeated scrape-abrasion tester shall be used. The instrument shall be
capable of rubbing a small cylindrical steel mandrel .025 to .028 inch (.64 to .71 mm) in diameter
repeatedly over the upper surface of the cable in such position that the longitudinal axis of the
steel mandrel and specimen are at right angles to each other with surfaces in contact. A weight
affixed to a fixture above the rubbing mandrel shall control the force exerted normal to the surface
of the insulation. A motor-driven, reciprocating-cam mechanism shall be used to deliver an
accurate number of abrading strokes in a direction parallel to the longitudinal axis of the specimen.
The number of strokes shall be measured by a counter. The length of the stroke shall be .375 inch
(9.52 mm) minimum and the frequency of the stroke shall be 60 cycles (120 strokes) per minute.
b. Test procedure. A test specimen shall be prepared by removing from the cable at least a 4-inch
(102 mm) length of two adjacent conductors containing identification. The specimen shall be
mounted in the specimen holder and 150 grams shall be applied through the steel mandrel to the
marked surface of the specimen. The counter shall be set at zero and the drive motor started.
The specimen shall be subjected to the specified number of cycles as stated in 3.20 and shall be
examined. Erasure or obliteration of a continuous line of identification marking shall constitute test
failure.
4.6.18 Shrinkage. A 12±.5-inch (305±13 mm) specimen of cable shall be cut so that the insulation
and conductor are flush at both ends. The specimen shall then be conditioned in an air-circulating oven
for six hours at the aging temperature listed in table I for the cable material specified in the applicable
specification sheet. The velocity of air past the specimen shall be between 100 and 200 feet per minute.
The velocity may be measured with the oven off and at room temperature. After conditioning, the
specimen shall be removed from the oven and allowed to cool to room temperature. The shrinkage of the
insulation shall then be measured as the greatest distance that the insulation has receded from either end
of the conductors. The measurement obtained at the end showing the greater shrinkage shall be
considered the shrinkage of the specimen. This shrinkage shall meet the applicable requirement.
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