MIL-DTL-13444H
4.7.10 Oil resistance (see 3.6.7). When hose samples are subjected oil resistance testing in
accordance with ASTM D380, immersion test for change in volume, shall meet the requirements of
3.6.7. The following details shall apply:
a. Each specimen shall be approximately 2 square inches (1290.32 m2) in area.
b. Three specimens shall be taken from the outer cover of untested hose, and three specimens
shall be taken from the inner tube of untested hose.
c. Each specimen shall be immersed in petroleum base oil IRM 903, or for 70 hours at a
temperature of 212°F ± 5°F (100° ± 2.78°C).
d. The change in volume reported for the outer cover shall be the average of the values obtained
from the three outer cover specimens tested.
e. The change in volume of the inner tube shall be the average of the values obtained from the
three inner tube specimens tested.
f. The change in volume of the outer cover and inner tube shall each be calculated to determine
conformance to 3.6.7.
4.7.11 Fuel resistance (see 3.6.8). Hose specimens with subjected to the fuel resistance test in
accordance with ASTM D380, immersion test for change, shall meet the requirements of 3.6.8. The
following details shall apply:
a. Three specimens shall be taken from the outer cover of untested hose, and three specimens
shall be taken from the inner tube of untested hose.
b. Each specimen shall be approximately 2 square inches (1290.32 mm2) in area.
c. Each specimen shall be immersed in reference fuel D 48 hours at a temperature of 80°F
±10°F (26.67 ± 5.56°C).
d. The change in volume reported for the outer cover shall be the average of the values obtained
from the three outer cover specimens tested.
e. The change in volume of the inner tube shall be the average of the values obtained from the
three inner tube specimens tested.
f. The change in volume of the outer cover and inner tube shall each be calculated to determine
conformance to 3.6.8.
4.7.12 Vibration resistance (see 3.6.9). When hose assemblies are subjected to vibration testing they
shall meet the requirements of 3.6.9. The following details shall apply:
a. Six hose assemblies with a free hose length of not less than 12 inches (30.48 cm) shall be selected
for testing.
b. Each specimen shall be arranged to provide an initial slack of .375 inch (9.53 mm) and an offset of
1.500 inches (38.10 mm) at an angle of 90° to the direction of stroke.
c. The specimens shall then be vibrated through an amplitude of .344 inch (8.74 mm) total excursion
of .688 inch (17.48 mm) at a rate of 1800 ± 10 cycles per minute for 200 hours.
d. During the vibration period, lubricating oil SAE viscosity grade 5W-40 in accordance with
MIL-PRF-2104 shall be circulated through each specimen at a pressure of 45 psig (3.10 bar) and at
a temperature of 250°F ± 5°F (121.11 ± 2.78°C).
e. At the end of the vibration period the specimens shall be examined for evidence of leakage or other
failure.
20
For Parts Inquires call Parts Hangar, Inc (727) 493-0744
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business