MIL-DTL-83054C
4.6.21.1 Single void ignitions. Single void ignitions shall be conducted at 3 psig (17.6 psia) initial
pressure with percent combustion volumes (percent Vc) of:
a. Types I, II, and IV: 5, 10, 15, 20, 30, 40, and 50 volume percent
b. Types III and V: 10, 20, 30, 35, 40, 50, and 60 volume percent
A minimum of one test shall be conducted for a given condition and all data such as bomb and system
pressure rise, test temperature, extent and location of arrestor damage, and any other related
information shall be submitted to the qualifying activity. A plot of pressure rise versus (percent)
combustion volume shall be submitted for each initial pressure condition. Repeat test may be conducted
on the material provided the damaged (burned) arrestor is replace after each test. All tests shall be
conducted at standard temperatures and conditions.
4.6.21.2 Arrestor volume. The amount of arrestor (thickness) required to prevent flame propagation
from Vc to Vv. when the combustion volume (Vc) is set at 9.1 and 16.7 volume percent and 0 and 3 psig
initial pressures shall be determined. Testing shall be conducted at 1 inch thick intervals and at the
minimum required arrestor thickness (Tm), a minimum of two tests shall be conducted. Repeat tests
may be run only if material is undamaged. All data including system and bomb pressure rise, test
temperatures, extent and location of arrestor damage, and any other related information shall be
reported. The ratio of arrestor volume to combustion volume or Va/Nc shall be calculated for each
minimum arrestor thickness (Tm).
4.6.22 Corrosion and adhesion test. One 4x3x3 inch baffle material specimen cut such that the 4 inch
dimension is in the direction of material rise shall be exposed in contact with 7075 aluminum alloy in
accordance with specification UNS A97075 for 14 days at 75° +5°F (23.9° +2.8°C) (room
temperature) and 95 +5% relative humidity.
4.6.22.1 Surface finish. Two sets of metallic plates shall be used having a surface finish of 5-15 micro-
inch finish obtained by lapping. The roughness shall he determined by a profilometer or equivalent
instrument. The roughness reading is the arithmetical average (AA) of the deviations in the surface
expressed in micro-inches measured normal to the surface. For these tests the surface finish should be
as follows:
5-15 micro-inch measure perpendicular to the lay at a roughness-width cutoff rating of 0.030 inch
and a maximum roughness-width rating of 0.015 inch. One set shall be clamped together with the
baffle material specimen such that the baffle material is compressed from 4 to 3 inches in thickness
in contact with the polished surfaces. This set along with the extra plates (controls) shall then be
exposed for 14 days at room temperature and 95 +5% relative humidity in a sealed container or
humidity cabinet. Test specimens should be oriented such that the metal plates are vertical in order
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