Table 5-7.Functions of Controls and Instruments
Air supply shutoff
Used for turning on and shutting off the shop air supply to the
Indicates the air pressure being applied to the hose undergoing
gauge (0-2,000 psi).
pneumatic test. A red follower pointer indicates the maximum
pressure applied to the hose. A manual reset knob is provided
for resetting the follower pointer to zero.
Regulated air pressure
Indicates the regulated air pressure being supplied to the oil
gauge (0-160 psi).
boost pump or the air boost pump.
Selects regulated air supply for the oil boost pump (hydraulic
testing) or the air boost pump (pneumatic testing).
Indicates the hydraulic pressure being applied to the hoses
gauge (0-2,000 and
undergoing hydraulic test. A red follower pointer on each gauge
indicates the maximum pressure applied to the hoses. A manual
reset knob is provided on each gauge for resetting the follower
pointer to zero.
Gauge shutoff valve.
Provides a means for shutting off pressure to the 0-2,000 psi oil
pressure gauge when using test pressures in excess of 2,000 psi.
Manifold bleed valve.
Used for bleeding air from the test hoses and manifolds before
applying full hydraulic test pressures. Also used to release
hydraulic pressure in the test hoses and manifolds after test.
Manifold bypass valve.
Bypasses the manifolds when turned on. Used to relieve
pressure on the manifolds at the completion of test.
Fluid flow sight
Provides a means for detecting air bubbles in the hydraulic oil
passing from the bleed valve to the oil reservoir.
Air booster inlet valve.
Used to turn on and shut off the unregulated air supply to the air
Air pressure regulator.
Used for setting the input air pressure to the oil boost pump
during hydraulic testing to give the desired hydraulic test
pressure. Also used for setting the input air pressure to the air
boost pump during pneumatic testing to give the desired
pneumatic test pressure.
Air booster shutoff
May be turned off after pressure is built up in the test hose; it
holds the test pressure and permits the air booster to be shut
Provides a means for releasing the air pressure in the test hose
Water shutoff valve.
Used for turning on the water to fill the pneumatic test chamber.