439
Federal Aviation Administration, DOT
Pt. 25, App. F
(6)
Instrumentation.
Provide a recording po-
tentiometer or other suitable calibrated in-
strument with an appropriate range to meas-
ure and record the outputs of the calo-
rimeter and the thermocouples.
(7)
Timing device.
Provide a stopwatch or
other device, accurate to
±
1%, to measure
the time of application of the burner flame
and burnthrough time.
(8)
Test chamber.
Perform tests in a suitable
chamber to reduce or eliminate the possi-
bility of test fluctuation due to air move-
ment. The chamber must have a minimum
floor area of 10 by 10 feet (305 by 305 cm).
(i)
Ventilation hood.
Provide the test cham-
ber with an exhaust system capable of re-
moving the products of combustion expelled
during tests.
(c)
Test Specimens.
(1)
Specimen preparation.
Prepare a minimum of three specimen sets of
the same construction and configuration for
testing.
(2)
Insulation blanket test specimen.
(i) For batt-type materials such as fiber-
glass, the constructed, finished blanket spec-
imen assemblies must be 32 inches wide by 36
inches long (81.3 by 91.4 cm), exclusive of
heat sealed film edges.
(ii) For rigid and other non-conforming
types of insulation materials, the finished
test specimens must fit into the test rig in
such a manner as to replicate the actual in-
service installation.
(3)
Construction.
Make each of the speci-
mens tested using the principal components
(
i.e.,
insulation, fire barrier material if used,
and moisture barrier film) and assembly
processes (representative seams and clo-
sures).
(i)
Fire barrier material.
If the insulation
blanket is constructed with a fire barrier
material, place the fire barrier material in a
manner reflective of the installed arrange-
ment For example, if the material will be
placed on the outboard side of the insulation
material, inside the moisture film, place it
the same way in the test specimen.
(ii)
Insulation material.
Blankets that uti-
lize more than one variety of insulation
(composition, density, etc.) must have speci-
men sets constructed that reflect the insula-
tion combination used. If, however, several
blanket types use similar insulation com-
binations, it is not necessary to test each
combination if it is possible to bracket the
various combinations.
(iii)
Moisture barrier film.
If a production
blanket construction utilizes more than one
type of moisture barrier film, perform sepa-
rate tests on each combination. For example,
if a polyimide film is used in conjunction
with an insulation in order to enhance the
burnthrough capabilities, also test the same
insulation when used with a polyvinyl fluo-
ride film.
(iv)
Installation on test frame.
Attach the
blanket test specimens to the test frame
using 12 steel spring type clamps as shown in
figure 7. Use the clamps to hold the blankets
in place in both of the outer vertical
formers, as well as the center vertical former
(4 clamps per former). The clamp surfaces
should measure 1 inch by 2 inches (25 by 51
mm). Place the top and bottom clamps 6
inches (15.2 cm) from the top and bottom of
the test frame, respectively. Place the mid-
dle clamps 8 inches (20.3 cm) from the top
and bottom clamps.
VerDate Sep<11>2014
12:50 Apr 30, 2019
Jkt 247046
PO 00000
Frm 00449
Fmt 8010
Sfmt 8002
Y:\SGML\247046.XXX
247046
spaschal on DSK3GDR082PROD with CFR