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|  MIL-P-48189D(AR)
4.5.10 Quality controls for each molding compound batch for
housing.
4.5.10.1 Resin/hardener weight ratio control. At the beginning
of production and at least once each four (4) hours of production,
or portion thereof, the inspector shall draw two (2) test shots with
the mixer set to expel the hardener and resin separately. The
hardener and resin of each shot shall be weighed individually to
verify that the ratio is between 1.8/1 and 2.2/1. If either shot
fails to meet the requirement, all items filled since the last
acceptable check shall be rejected. Further, the mixer shall be
corrected and shall pass the above test before being returned to use.
4.5.10.2 Mixing and cure control. One (1) test bar from each
batch of molding compound (see 4 5.10 .1) shall be molded at the same
time the batch is used to mold housings, for lot acceptance
testing. Vibration and evacuation as necessary may be used to mold
the bar. The mix ratio limits shall be 2.0/1.0 5% (1.8/1.0 to
2.2/1.0). The test bar shall be processed with the items molded
from the batch of molding compound which the bar represents i.e.,
the bar shall be cured in the same ovens and subjected to the same
temperatures for the same time periods as the items is represents.
After completion of the curer the bar shall be tested for ultimate
compressive strength, as specified in ASTM D-695 (69) except that
the specimen dimensions shall be 0.5 inch by 0.5 inch by 1.0 inch or
0.5 inch diameter by 1.0 inch long. The ends shall be flat and
parallel to within . 003 inch, and shall be perpendicular to the long
axis of the specimen. Speed of testing shall be as specified in the
ASTM. IF the results of this test are outside the limits specified
in 3.16, the items represented by the bar shall be rejected.
4.5.11 Temperature control during molding/cure operations.
Whenever the preform assembl y, the housing, or munition is subjected
to heating in-ovens, temperature records shall be maintained and
reviewed to assure that the minimum temperature has been reached,
and that the maximum temperature has not been exceeded. If any
units have been subjected to temperatures beyond the maximum limit
at any time, regardless of duration, they shall be rejected.
Temperature-measuring instruments shall be approved and calibrated
in accordance with 4.4.5.
4.5.12 Functioning of the electronic circuitry of the housing,
timing and fuzing. For test procedures related to the functioning
(See
of the electronic circuitry of the housing, timing and fuzing.
Appendix A of this specification.)
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