MIL-DTL-5578D
________144_________
K =
(sp.gr.)(29.573)(3.142)R2
Where sp.gr. = Specific gravity of test fluid at 77 °F (25 °C).
R = Inside radius of test cup expressed in inches.
Alternate test methods may be used if approved by the procuring activity. A test apparatus
utilizing a grooved mounting flange with mating head in the retainer ring has been found to yield
more consistent results for some materials.
4.5.4.4 Seam adhesion (immersion). The seam adhesion of the inner layer ply to itself
before and after immersion in ASTM-D471 Ref Fuel B test fluid for 72 hours at a temperature of
135 +3 °F (57 +2 °C) shall be tested within 4 hours along the length of the seam by the strip-
back method, using a jaw separation rate of 2 inches per minute in accordance with
ASTM-D413. Where the adhesion of the seam is less than the strength of the material, the
adhesion shall be a minimum of 6 pounds per inch.
4.5.4.4.1 Seam adhesion. Seam adhesion of the inner layer ply to itself shall be tested by
cutting a strip of inner layer material 1-inch wide. This seam shall be perpendicular to and
midway in the length of the strip. When a tensile load has been applied parallel to the length of
the strip to break the strip, there shall be no failure of the seam.
4.5.4.5 Slit resistance. A section of the composite cell construction sample shall be selected.
A slit of the inner-layer ply, 1 inch long to the depth of the sealant, shall be cut parallel to the
calender grain, if present, or to the direction of minimum tear resistance. The test section shall
be 5 inches long with width sufficient to clamp in a vise, with the jaws of vise 1 inch from the
slit when the test section is bent 180 degrees. The slit shall be parallel to vise jaws and on the
outside of the bend. The sample shall be held in this folded condition for 1 hour and the increase
in length of the slit noted. The slit shall not increase more than 0.25 inch.
4.5.4.6 Inner-liner adhesion. The adhesion of the inner-layer ply to the sealant shall be
tested by the strip back method, using a jaw separation rate of 2 inches per minute in accordance
with FED-STD-601, Method 8011. The adhesion shall be a minimum of 6 pounds per inch.
4.5.5 Test cubes. The sample phase I test cubes shall be subjected to the tests described in
the following paragraphs.
4.5.5.1 Fuel resistance of exterior surfaces. The test cubes shall be placed in a container
large enough to permit immersion of the self-sealing portion of the test cube in JP-5 or JP-8 or
other test fluid as specified by the procuring activity. The cells shall be immersed for 60 days or
as directed by the procuring activity. Test temperature shall be above 65 ºF (18 ºC). The test
cubes shall then be removed and examined for swelling, separation, blisters, pinhole material
15
For Parts Inquires submit RFQ to Parts Hangar, Inc.
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business