MIL-DTL-14055G
TABLE I. Change in physical properties.
Physical properties
Change
Volume
+5 to +20 percent
Outside diameter (lip)
0 to +5.75 percent
Outside diameter (base)
0 to +5.75 percent
Durometer hardness
0 to -15 points
3.4.5 Heat-pressure stroking. When tested as specified in 4.7.6, the cylinder cups shall conform to the
following requirements.
3.4.5.1 Volume loss. The volume loss of brake fluid due to leakage past the secondary cup of the master
cylinder or past the wheel cylinder cups during any 24,000-stroke period in the test, shall not exceed 3.5
milliliters or 10 milliliters for the 70,000-stroke period. (see 4.7.6.3)
3.4.5.2 Pressure change. The pressure in the simulated brake system shall not vary more than ± 50 psi
(3.45 bars) from the initial stroking pressure throughout the 70 - hour test period. (see 4.7.6.3)
3.4.5.3 Leakage. After the 24-hour cooling period specified in the test, the following shall be cause for
rejection (see 4.7.6.3):
1. Constant dampness past the cups on two or more inspections due to leakage.
2. Fluid discoloration of the filter paper on two or more inspections due to leakage.
3.4.5.4 Lip diameter interference. After test, the minimum lip diameter of the cups shall be greater than
the cylinder bore by the minimum dimensions shown in table II. This dimensional quality of a cup is
known as its lip diameter interference. (see 4.7.6.3)
TABLE II. Lip diameter interference. 1/ 2/
Cup Size (diameter)
Wheel Cylinder Cup
Master and Slave Cylinder Cup
To 1 in. (2.54cm)
0.030 in. min. (0.0762cm)
0.020 in. min. (0.0508cm)
1 to 1.5 in. (2.54 to 3.81cm)
0.035 in. min. (0.0889cm)
0.025 in. min. (0.0635cm)
1.5 to 2 in. (3.81 to 5.08cm)
0.040 in. min. (0.1016cm)
0.030 in. min. (0.0762cm)
1/ Dimensions are in inches.
2/ Metric equivalents are given for information only.
3.4.5.5 Appearance of rubber cups. At the completion of the test, the cylinder cups shall show no more
than a moderate amount of shipping, scuffing, blistering, cracking, tackiness, or change in shape from
original appearance. (see 4.7.6.3)
3.4.5.6 Hardness. Rubber cups shall not decrease in hardness by more than 15 points. (see 4.7.6.3)
3.4.5.7 Corrosion. Pistons and cylinder bore shall not show corrosion as evidenced by pitting to an
extent discernible to the naked eye. (see 4.7.6.3)
3.4.5.8 Sedimentation. Not more than 1.5 percent sediment by volume shall be in the centrifuge tube
after the fluid from the stroking test has been tested as specified in 4.7.6.3. The sedimentation shall show
no crystalline particles. (see 4.7.6.3)
3.4.6 Corrosiveness. When the cylinder cups have been tested for corrosiveness as specified in 4.7.7,
the test results shall be as follows.
3.4.6.1 Metal strips. The metal strips shall not be pitted nor etched. (see 4.7.7.3) The permissible loss in
weight of the strips shall be as specified in table III.
4
For Parts Inquires call Parts Hangar, Inc (727) 493-0744
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business