Figure 99. Air cylinder for testing propellant actuated devices.
Figure 100. Thruster and instrumentation fixture.
This transducer is very sensitive, does not
pressure-time curve produced with this instrumentation
load down the thruster, and eliminates
is used to determine peak pressure and time-to-peak
problems resulting from vibrations during
pressure.
the stroke.
e. Leak-Detection Fixture.
d. Pressure Chambers. Pressure chambers are
(1) Ordinarily, cartridges are the only items
used for testing gas-generated devices. The fixture is a
which are tested for leaks. For this
cylindrical chamber of a specified volume, usually 0.062
purpose, a radioactive tracer method is
cubic inch of 1 cubic inch. The chamber is provided
used.
with 2 ports: one for the hose which leads the gas into
(2) In this test, a sealed cartridge is placed in
the chamber, and the other to permit insertion of a
a pressure chamber and exposed to
piezoelectric gage or pressure pickup (fig. 101). The
radioactive gas (Krypton 85).
The
difference between the internal and the
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