Bendix Commercial Vehicle Systems QR-N QUICK RELEASE VALVE - Manual (Page 2)

2
RELEASE
When air pressure is reduced or removed from the QR-N ™
valve supply port, the air pressure on the delivery side of the
diaphragm is greater than that on the supply side. The higher
delivery side pressure holds the outer edge of the diaphragm
against the upper body sealing lip while simultaneously
moving the center portion away from the exhaust port. Air
from the delivery ports flows out the exhaust. When air
pressure on the delivery side of the diaphragm equals the
pressure on the supply side, the center portion of the
diaphragm moves into contact with the exhaust port.
PREVENTIVE MAINTENANCE
Important: Review the Bendix Warranty Policy before
performing any intrusive maintenance procedures. A warranty
may be voided if intrusive maintenance is performed during
the warranty period.
No two vehicles operate under identical conditions, as a
result, maintenance intervals may vary. Experience is a
valuable guide in determining the best maintenance interval
for air brake system components. At a minimum, the QR-N
™
valve should be inspected every 12 months or 3600 operating
hours, whichever comes first, for proper operation. Should
the QR-N
™ valve not meet the elements of the operational
tests noted in this document, further investigation and service
of the valve may be required.
WARNING! PLEASE READ AND FOLLOW
THESE INSTRUCTIONS TO
AVOID
PERSONAL INJURY OR DEATH:
When working on or around a vehicle, the following
general precautions should be observed at all times.
1. Park the vehicle on a level surface, apply the
parking brakes, and always block the wheels.
Always wear safety glasses.
2. Stop the engine and remove ignition key when
working under or around the vehicle. When
working in the engine compartment, the engine
should be shut off and the ignition key should be
removed. Where circumstances require that the
engine be in operation, EXTREME CAUTION should
be used to prevent personal injury resulting from
contact with moving, rotating, leaking, heated or
electrically charged components.
3. Do not attempt to install, remove, disassemble or
assemble a component until you have read and
thoroughly understand the recommended
procedures. Use only the proper tools and observe
all precautions pertaining to use of those tools.
4. If the work is being performed on the vehicle’s air
brake system, or any auxiliary pressurized air
systems, make certain to drain the air pressure from
all reservoirs before beginning ANY work on the
vehicle. If the vehicle is equipped with an AD-IS
™
air dryer system or a dryer reservoir module, be
sure to drain the purge reservoir.
5. Following the vehicle manufacturer’s
recommended procedures, deactivate the electrical
system in a manner that safely removes all
electrical power from the vehicle.
6. Never exceed manufacturer’s recommended
pressures.
7. Never connect or disconnect a hose or line
containing pressure; it may whip. Never remove a
component or plug unless you are certain all
system pressure has been depleted.
8. Use only genuine Bendix ® replacement parts,
components and kits. Replacement hardware,
tubing, hose, fittings, etc. must be of equivalent
size, type and strength as original equipment and
be designed specifically for such applications and
systems.
9. Components with stripped threads or damaged
parts should be replaced rather than repaired. Do
not attempt repairs requiring machining or welding
unless specifically stated and approved by the
vehicle and component manufacturer.
10. Prior to returning the vehicle to service, make
certain all components and systems are restored
to their proper operating condition.
OPERATING AND LEAKAGE TESTS
1. Apply 100 psi (689 kPa) air pressure to the supply port
of the QR-N ™ valve and note that the device connected
to the QR-N ™ valve responds promptly.
2. With 100 psi (689 kPa) air pressure applied to the
QR-N ™ valve SUPPLY port apply a soap solution to the
exhaust port and around the junction of the upper and
lower body halves.
A. No leakage is permitted between the body halves.
B. Leakage of greater than a 1" (25.4 mm) bubble in 3
seconds at the exhaust port is unacceptable.
3. Release the air pressure at the supply port and note
that the device connected to the QR-N ™ valve responds
promptly and returns to a zero air pressure condition.
4. If the QR-N ™ valve does not function as described or if
leakage is excessive, it is recommended that it be
replaced with a new or remanufactured unit or repaired
using a genuine Bendix maintenance kit.
5. Use only genuine Bendix replacement parts and
components.
A. Only components, devices, mounting and attaching
hardware specifically designed should be used.
B. Replacement hardware, tubing, hose, fittings, etc.
should be of equivalent size, type, length, and
strength as the original equipment.
C. Make certain that when replacing tubing or hose, all
supports, clamps or suspending devices that were
originally installed by the vehicle manufacturer are
reinstalled.