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10-1
SECTION 10
INLET CONTROL VALVE
INLET CONTROL VALVE
– This device is located at the intake flange of the 1st stage compressor. A
spring-loaded pneumatic cylinder actuates the valve. During compressor operation (at least 5 Hz 1st
stage compressor shaft speed), an air pressure signal (60 psig min) fed into the actuator overcomes the
internal spring load and opens the valve. During stopped operation modes (e.g., commanded from
keypad or initiated by protective shutdown), the air signal is vented allowing spring load to close the
valve. This prevents trapped air and oil from exiting through the inlet filter. The pneumatic actuator has a
maximum operating pressure of 125 psig. Refer to Figure 10-1, for valve body part descriptions.
Figure 10-1 – INLET CONTROL VALVE (BODY)