SECTION 2: DESCRIPTION
CAS40P 40 CFM / 100 PSIG
PAGE - 8
®
An Oshkosh Corporation Company
KEY
DESCRIPTION
A
RELIEF VALVE (x 2) - Rated at 70 PSI
B
RELIEF VALVE - Rated at 200 PSI
Figure 2-4: Pressure Relief Valves
A
A
B
The compressor unit has a built-in hydraulic manifold
which has a directional control valve (solenoid) and a
pressure relief valve (see
Section 8.9
[12V] or
8.10
[24V]).
The pressure relief valve protects against an over-
pressure condition by diverting the oil to the return line if
such a condition occurs.
2.2.6 PRESSURE RELIEF VALVES
See
Figure 2-4
.
There are three pressure relief valves
located on the compressor unit assembly: one each on
the cylinder heads (70 psig rating), and one on the
service assembly piping (200 psig rating). These spring-
backed, normally closed valves serve as safety devices
that protect against over-pressurization. As the pressure
begins to approach 70 psig for each of the head unloader
valves, its relief valve will crack open to slowly relieve
pressure. This siphoning action serves to vent excessive
pressure level build-up of air to atmosphere in real time
operation sequence. The valve located at the service
assembly piping regulates pressure in the same way,
bleeding off excessive air pressure over 200 psig.
KEY
DESCRIPTION
KEY
DESCRIPTION
A
RELIEF VALVE ADJUSTMENT
I
C
HOUR METER
B
PRESSURE GAUGE
D
OIL LEVEL SIGHT GLASS
I
The pressure relief valve is set at the factory.
DO NOT
adjust the pressure relief valve; consult the IMT Service
Department for pressure relief resets.
Figure 2-3: Instrumentation Locations
D
A
B
C
Manual #99905382 Rev 02
(JUNE 2018)
