BENDIX PRESSURE PROTECTION VALVES Manual

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Bendix PR-2 , PR-3
DESCRIPTION
The pressure protection valve is a normally closed, pressure
control valve which can be referred to as a non-exhausting
sequence valve. These valves are used in many different
applications. An example would be in an air brake system
to protect one reservoir, or reservoir system from another,
by closing automatically at a preset pressure should a
reservoir system failure occur. The valves can also be used
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PR-3 OR PR-4 PRESSURE PROTECTION VALVES
SPRING
SUPPLY
PORT
PR-4 ™ PRESSURE PROTECTION VALVE
™ ™
& PR-4 Pressure Protection Valves
CAP
PISTON
INLET
VALVE
DELIVERY
PORT
to delay filling of auxiliary reservoirs to insure a quick build-up
of brake system pressure.
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The PR-2 and PR-4 pressure protection valves have one
1/4" N.P.T.F. supply port and one 1/4" N.P.T.F. delivery port
which are identified. Both valves are provided with two 9/32"
mounting holes through the body. The closing pressure of
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the PR-2 valve is externally adjustable while the PR-4
valve has a fixed setting.
CAP
INLET
VALVE
SUPPLY
PORT
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PR-3 PRESSURE PROTECTION VALVE
PRESSURE
REGULATING
SPRING
EXHAUST
VENT
PISTON
O-RING
PISTON
SUPPLY
PORT
SPRING
RETAINER
INLET
VALVE
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PR-2 PRESSURE PROTECTION VALVE
SPRING
PISTON
CHECK
VALVE
DELIVERY
PORT
PISTON PLUG
PISTON PLUG
O-RING
VALVE STEM
INLET
VALVE SPRING
DELIVERY
PORT
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