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TM 10-3835-219-14
W A R N I NG
A baffle, composed of metal, wood or sandbags, approximately 3 feet (0.91 m)
wide and 3 feet (0.91 m) high, should be placed between the water inlet of hose
and operator controlling hydrostatic pressure to protect operator in case of a
coupling retention.
(10) Attach shutoff nozzle on test caps (4) with a petcock to coupling at end of hoseline (1).
WARNING
In making service pressure test, special care must be exercised to remove all air
from hose before nozzle or test cap valve is closed and pressure becomes greatly
compressed, and hose can ship violently, if pressure is suddenly released by a
hose burst. A blown-off coupling or coupling ring can act like a high velocity mis-
sile which can result in serious injury or damage to property.
It should be understood that development of test pressures introduces a serious
accident potential even when recommended procedures are followed.
(11) Directly in back of nozzle or coupling, secure hose in order to avoid any possible whipping or uncontrolled
reaction of hoseline that may occur when hoseline is subject to hydrostatic pressure.
(12) After filling hoseline, observe each end of each length of hose at coupling to ensure coupling does not slip
during test.
(13) Check all couplings for leakage, replace gaskets and/or straps as required.
WARNING
Open and close nozzles and valves gradually to prevent water hammer and pres-
sure surges which may burst hose and, in turn, causes bodily injury. Water ham-
mer is the surge of pressure caused when a high velocity flow of water is abruptly
shut off. The pressure exerted by the flowing water against the closed system can
be as much as seven times the static pressure.
(14) Slowly raise pressure to 150 psig (10.55 kg/cm2).
(15) Hold at this pressure for 5 minutes.
WARNING
Never straddle hose while under pressure and never stand at either end in line
with hose.
(16) During the time hose is under pressure, inspect entire length of hose for any leaks or defects.
(17) After inspection and the 5 minute pressure hold, slowly reduce pressure.
(18) Close pump discharge valve and open nozzle or test cap to drain hose.
Change 1 4-7
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