188.8.131.52 A nitrogen bottle of sufficient volume to purge the breech mech-
anism air flasks and the low pressure pneumatic system.
184.108.40.206 A 0.024 plus or minus 0.0005 inch diameter orifice for the high
pressure air source of 220.127.116.11.
4:4.5 Test procedures.
The following tests shall be performed:
When working with high pressure air, observe
all safety precautions (see 3.2.8).
18.104.22.168 Hydrostatic pressure test, breech mechanisms. With the breech
mechanisms removed from the tube assembly, remove Pressure Gage 1623922
the breech mechanisms shall be filled with
and insert a plug in the void.
This pressure shall be
water and pressurized to 4500 plus 20 minus O psig.
maintained for 10 minutes minimum without failure of any part. At the com-
pletion of this test, reduce the pressure to zero, drain the breech mechanism,
and purge with dry nitrogen. Reinstall Pressure Gage 1623922.
During the hydrostatic pressure tests, exercise
care to stay clear of the safe-ready cylinder
22.214.171.124 High Pressure Pneumatic system Pressure drop test. `Ibis test shall
be performed on each barrel of the torpedo tube assembly. Remove the breech
mechanism and securing mechanism from the barrel. Secure the nipple attached
to the manifold and piping assembly to a shutoff valve or other suitable blanking
device. Adjust the air source to 2000 plus O minus 20 psig and attach it
through a 0.024 plus or minus 0.0005 inch diameter orifice to the barrel
pneumatic system using a pressure fitting adapter (NAVORD Dwg 3245120). Actuate
the firing solenoid valve and allow the pneumatic system line pressure to
The pressure as measured on the barrel side of the orifice shall
stabilize at 1350 psig minimum. Repeat this test with the securing mechanism
installed in the barrel. The pressure in the pneumatic system shall then
stabilize at 750 psig minimum. At the conclusion of this test there shall
be no deformation or failure of any part of the pneumatic system.
126.96.36.199 Hydrostatic pressure test, low Pressure pneumatic system. Fill
the 100-150 psig system with water and pressurize to 225 psig. Maintain this
pressure for 10 minutes with the barrel in the safe condition and for 10
minutes with the barrel in the ready condition. There shall be no failure of
any part of the pneumatic system. After completion of the hydrostatic test,
thoroughly purge water from the system with nitrogen.