MIL-PRF-10924H
2/ Worked stability shall be performed in accordance with 4.3.5.
3/ Salt water corrosion resistance test shall be performed in accordance with 4.3.6.
4/ Biodegradation test shall be performed in accordance with 4.3.7.
4.3.4 Low temperature torque. The test shall be conducted at -54 +0.5°C according to the
Federal Test Method 791, 7501. The breakaway (maximum) torque shall be determined at the
beginning of the operation and the running torque shall be determined after five minutes of
operation. Both determinations should be calculated by the averaging of four test runs. If the
test apparatus is not available, the ASTM D1092 test method shall be used to determine the
breakaway torque at -54°C as follows: The apparent viscosity shall be determined at shear rate,
25 reciprocal seconds. This value is then converted to the breakaway torque Newton-meters
(N⋅m) using the following correlation equation (1). If this alternate method is used, only
breakaway torque values can be reported. However, in case of referee disputes, only the results
from the low temperature torque test method shall be accepted. Failure of the grease to meet the
requirements of table I shall constitute failure of this test.
Breakaway torque (N.m) = 2.36 x (apparent viscosity at 25 sec-1 x 10-4) +1.48
(1)
[Standard error: 0.373]
4.3.5 Worked stability test. The test shall be performed using the standard procedure of
ASTM D217 with the following modifications. A change in worked penetration of the grease of
more than 60 units higher or 25 units lower than the original worked penetration shall constitute
failure of this test.
a. Work a sample of the test grease on a motorized grease worker for 10 0000 double
strokes (approximately 28 hours) in accordance with the procedure described in
ASTM D217 for prolonged worked penetration.\
b. Immediately after the grease has been subjected to 10 0000 double strokes, bring the
grease worker and the sample to 25 ±0.5°C in accordance with the procedure
described in ASTM D217 for prolonged worked penetration.
c. Immediately after the test grease sample reaches 25 ±0.5°C, determine the prolonged
worked penetration of the grease.
4.3.6 Salt water corrosion test. This test shall be performed using the standard procedure
of ASTM D5969 with NaCl solution (1 percent NaCl by weight in distilled water). Failure of
the grease to meet the requirements as defined in ASTM D5969 under rating shall constitute
failure of this test.
4.3.7 Biodegradability. Determine the percent of theoretical CO2 evolved (P) of the
grease IAW ASTM D 5864 or O2 consumption (D) according to ASTM D 6731 or the
percentage of biodegradability can be determined according to ASTM D7373. A value of
biodegradability less than 60 % in 28 days shall constitute failure of this test.
4.3.8 Compatibility. Two grease samples shall be mixed using an electric mixer in 10 %,
50 %, and 90 % ratios. These mixture samples must be stored at room temperature for seven
days. Then, the mixture samples shall be tested according to Table III except for biodegradation
test. Failure of each mixture sample to meet the requirements of table I shall constitute failure of
7
For Parts Inquires call Parts Hangar, Inc (727) 493-0744
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business