1
SD-03-2010
Bendix
®
PR-2
™
, PR-3
™
& PR-4
™
Pressure Protection Valves
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
to delay filling of auxiliary reservoirs to insure a quick build-up
of brake system pressure.
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
the PR-2
™
valve is externally adjustable while the PR-4
™
valve has a fixed setting.
DELIVERY
PORT
SUPPLY
PORT
PISTON
SPRING
INLET
VALVE
CAP
PR-4
™
PRESSURE PROTECTION VALVE
INLET
VALVE
PISTON
SPRING
CHECK
VALVE
CAP
PR-3
™
PRESSURE PROTECTION VALVE
PR-3
™
OR PR-4
™
PRESSURE PROTECTION VALVES
INLET
VALVE SPRING
INLET
VALVE
PISTON PLUG
O-RING
PRESSURE
REGULATING
SPRING
VALVE STEM
PISTON PLUG
PR-2
™
PRESSURE PROTECTION VALVE
EXHAUST
VENT
PISTON
O-RING
PISTON
SPRING
RETAINER
SUPPLY
PORT
DELIVERY
PORT
SUPPLY
PORT
DELIVERY
PORT
