MIL-DTL-11891G(AT)
analyzed by gas chromatography/mass spectrometry. Following desorption of the additives, the
remaining sample will be pyrolyzed and analyzed by gas chromatography/mass spectrometry. A
baseline scan will be performed on the material submitted for qualification. Future results will be
compared with the baseline to determine that there are no new peaks appearing, no ingredients
missing and no substitutions in subsequent production runs (see 4.7.1.13).
3.3.4 Track roadwheel path and ground pad performance tests. All material property
tests indicated in table II for the track roadwheel path and ground side pads (integral and/or
replaceable) shall be conducted in accordance with the referenced ASTM's, the Process
Fingerprint Plan (see 3.3) and in accordance with the requirements of this specification. The
following tests will be performed on qualification samples taken on unvulcanized samples at the
final mixing of the compound (see 4.3.1.3) and be of an equivalent state of cure as compounds
being submitted for qualification: specific gravity, hardness, tensile strength, elongation, tensile
stress, aged properties, brittleness point, cure meter; ozone resistance, TGA, GC mass spec. The
following tests will be performed on qualification samples taken on vulcanized samples: hardness,
tensile strength, elongation, tensile stress, aged properties, ozone resistance, adhesion, and blow-
out (see 4.3.1.4).
3.3.4.1 Specific gravity. Specific gravity tests will be performed on the pad (integral
and/or replaceable) and roadwheel path compounds subject to qualification test in accordance
with ASTM D792. Specific gravity tests will be performed on a minimum of 3 samples from each
compound submitted for qualification and all results provided to the Government. Samples shall
be taken from unvulcanized compounds at the final mixing stage (see 4.7.2.1).
3.3.4.2 Hardness - durometer. Hardness tests will be performed on laboratory specimens
of pads (integral and/or replaceable) and roadwheel path compounds subject to qualification in
accordance with ASTM D2240. As a minimum, hardness tests shall be conducted on 3 samples
each of the unvulcanized compounds taken from the final mixing stage as well as 3 samples of the
finished components. The results of all tests shall be provided to the Government (see 4.7.2.2).
3.3.4.3 Physical properties of pad and roadwheel path compounds. Physical property
tests, as a minimum, will be conducted on specimens taken from each compound used in the pads
(integral and replaceable) and roadwheel path in accordance with ASTM D412, table II and
figures 1, 2, 3 and 4. The three specimens for the style B (Tl54) ground pad shall be taken as
shown in figure 1. The three specimens for the style B (TI54) roadwheel path shall be taken as
shown in figure 2. The three specimens for the style A (Tl07) ground pad shall be taken as shown
in figure 3. The three specimens for the style A (Tl07) roadwheel path shall be taken as shown in
figure 4. The three specimens for the style B (T157I) ground pad shall be taken as shown in
figure 6. All test results will be reported to the Government. The production tolerance for the
physical property tests based on the average values established during qualification tests will be
+15% for tensile strength, +15% ultimate elongation, and +15% for 200% modulus (see 4.7.2.3,
4.7.2.5 and 4.7.2.7).
10
For Parts Inquires call Parts Hangar, Inc (727) 493-0744
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business