(4)  
A description of the flow-control-and-shutoff-valve components:
 (a)  
The valve flow section
 1)  The valve flow section is a venturi-type tube assembly. A butterfly plate, attached to a shaft, is in the assembly. The valve flow section measures 4 inches in diameter and
 14.25 inches long. All other valve components are attached to the valve flow section.
 (b)  
The mechanical-manual-override valve
1) The mechanical-manual-override valve supplies a way for the flow control valve to be manually closed. It has two valve seats, a ball, and a manual override actuator.
 (c)  
The pneumatic actuator
 1)  The pneumatic actuator is the mechanism that controls the butterfly plate in the valve flow section. The pneumatic actuator has an actuator housing assembly and an actuator linkage assembly.
 2)  The actuator housing includes an actuator diaphragm that divides the pneumatic actuator into two chambers. Chamber N bleeds to the mechanical manual override valve. The ambient-pressure-sensing chamber bleeds to ambient. The ambient-pressure-sensing chamber has a spring to push the actuator diaphragm against the chamber N.
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MAINTENANCE MANUAL
SEEA 
FWD 
ALTITUDE 
ADJUSTMENT H
SOLENOID 
(INNER SCREW)
VALVE ASSY B ELECTRICAL MANUALSLAVE SERVO VALVE BLEED NOZZLE CONNECTION 
ADJUSTMENT L  OVERRIDE CLOSED STOP
ADJUSTMENT K VISUAL ACTUATOR ADJUSTMENT POSITION INDICATOR 
TESTPORT D MANUAL PNEUMATICCONTROL 
ADJUSTABLE ACTUATOR
ROD 
ORIFICE F 
ASSEMBLY (NORMAL FLOW) CAM ASSEMBLY 
SEE C CLOSED POSITION SWITCH ELECTRICAL CONNECTOR
ADJUSTABLE ORIFICE G TEST PORTS 
SOLENOID VALVE 
ASSY A ELECTRICAL 
CONNECTION
MANUALSEE B OVERRIDE 
VALVE 
ELECTRO-MAGNETIC ACTUATOR 
CONTROL VALVE  BODY ASSY 
ELECTRICAL CONNECTOR 
A
Flow Control and Shutoff Valve 
Figure 3 (Sheet 1)
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MAINTENANCE MANUAL
ASSY 
TEST PORT R 
J 
INLET PRESSURE SENSING TUBE ASSY 
THROAT PRESSURE SENSING TUBE ASSY
Flow Control and Shutoff Valve 
Figure 3 (Sheet 2)
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MAINTENANCE MANUAL
ZERO DIFFERENTIAL
PRESSURE VALVE
ADJUSTABLE ORIFICE F(NORMAL FLOW)
ACTUATOR
CHAMBER M
SONICLEVER NOZZLE CHAMBER C 
SUPPLYNOZZLE ANEROID
ADJUSTABLE
CHAMBER D
ORIFICE E
(HIGH FLOW) 
FLAPPER TORQUE
ADJUSTMENT MCHAMBER Q SLAVE SERVOMOTORVALVE 
SOLENOID VALVE A
ADJUSTMENT L ADJUSTABLE ORIFICE GBLEED NOZZLE(MINIMUM AIRFLOW SINGLEPORT PACK OPERATION) 
ELECTROMAGNETIC
BLEED NOZZLE
ADJUSTMENT K
ALT ADJUSTMENT H CONTROL VALVE POPPET
VALVE 
SOLENOID
LATCH 
REFERENCEBALL VALVE
PRESSURE
ASSEMBLY 
REGULATOR
MANUAL
CLOSED STOPCONTROL
ROD 
CLOSE
ADJUSTMENT
SOLENOID VALVE B
CHAMBER N
PNEUMATIC
ACTUATOR
THROAT PRESSURE
BALL 
SENSING PROBE AMBIENT
VENTOPEN
BUTTERFLYAIR FLOW 
PLATE
MANUAL OVERRIDE
ACTUATOR 
VALVE BODY
INLET PRESSURECAM
CLOSED VISUAL POSITIONSENSING PROBE 
INDICATOR
SWITCH
POSITION 
OPEN CLOSE NOTE: ALL VENTS TO AMBIENT
MECHANICAL MANUAL OVERRIDE VALVE
Flow Control and Shutoff Valve Operation
 
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