1
Two .28 inch mounting holes are provided in the die cast
zinc body for panel or frame mounting. Two steel hex cap
nuts at the ends of the cylindrical valve body retain the
internal components. All air connection ports contain pipe
threads. Lettering embossed in the valve body identifi es
two of the four ports in the valve. Refer to the chart below
and fi gure 1.
Air Connection
Body Ident.
Thread Size
Supply
SUP
1/4” P.T.
Delivery
DEL
1/4” P.T.
Control
NONE
1/4” P.T.
Vent
NONE
1/8” P.T.
IMPORTANT: A vented, socket head vent plug is
installed in some SS-1
™
valves, however, an exhaust
check valve should be installed in the threaded vent
port when the SS-1
™
valve is mounted outside the cab
in unprotected environments. See Figure 2.
DESCRIPTION
The SS-1
™
shut-off valve (fi gure 1) is a pilot operated,
air controlled, on-off, non-graduating, non-exhausting
pneumatic control valve. The valve is primarily used to
delay, sequence, or control airfl ow from various devices in
the air brake system. It can be operated either in a pilot or
automatic mode using different air connection methods.
The SS-1
™
valve is a general purpose valve used in a
variety of applications on trucks, buses, tractors, trailers
and converter dollies. It is offered in a variety of pressure
settings to accommodate applications where automatic
operation is required. The most common application of
the SS-1
™
valve is in the tractor protection system of a
truck tractor.
Important Note:
The SS-1
™
shut-off valve is
application specifi c due to its pressure settings. It is
therefore important to use the proper part number
when replacement is required.
IN ADDITION: The
SS-1
™
shut-off valve and SV-1
™
synchro valves are
identical in appearance and similar in operation but
have substantial internal differences and must not
be confused or used interchangeably.
The SV-1
™
synchro valve incorporates an internal exhaust passage
through its piston, which allows delivery pressure to
be vented to atmosphere while the SS-1
™
does not.
Refer to Service Data Sheet, SD-03-4020, for more
information on the SV-1
™
synchro valve. Service Data
Sheets can be obtained by calling 1-800-AIR-BRAKE
or by visiting www.bendix.com on the Internet.
1/8" PIPE THREAD
Note:
Either style may be installed in the SS-1
™
valve
FIGURE 2 -
EXHAUST CHECK VALVE STYLES
FIGURE 1-
SS-1
™
SHUT-OFF VALVE
PISTON O-RING
MOUNTING
HOLES
DELIVERY
PORT
SUPPLY
PORT
VENT PLUG WITH
1/8" P.T. VENT
INLET VALVE
PISTON
INLET VALVE
SPRING
PISTON RETURN
SPRING
PISTON O-RING
1/4" P.T.
CONTROL PORT
1/4" P.T.
SUPPLY PORT
1/4" P.T.
DELIVERY
PORT
MOUNTING
HOLE
CONTROL
PORT
VENT PORT
CONTROL PORT
CAP NUT
CAP NUT O-RING
SUPPLY PORT
CAP NUT
CAP NUT O-RING
SD-03-4010
Bendix
®
SS-1
™
Shut-Off Valve