747-400 AMM 飞机维护手册 气动系统 PNEUMATIC SYSTEM(26)

曝光台 注意防骗 网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者

 J.  The ASCTU has the power and the logic circuitry to control and monitor the engine air supply components. It also sends signals to the EFIS/EICAS interface units (EIU's) and supplies information for fault isolation.
 2.  High Pressure Shutoff Valve (HPSOV) (Fig. 5)
___________________________________
 A.  The HPSOV is installed on the engine in the 9:00 o'clock position approximately three feet aft of the fan frame. It is a 5.5 inch butterfly valve. A piston type actuator drives the butterfly valve through a link and crank. The valve contains two plunger-type position switches. Both the open and closed position switches send signals to the ASCTU.
 (1)  
The HPSOV has a valve shaft extension that will permit you to manually open or close the valve with a wrench. The valve actuator case has a lockpin that can be removed. If the valve must be locked closed, the lockpin is removed from the actuator case. This lets valve control pressure go to ambient. The pin is installed through the valves' manual control linkage into a threaded hole to lock the valve in the closed position. The valve housing has markings, (OPEN and CLOSED), to give visual indication of the valve position.

 (2)  
The pneumatic servo pressure from the high pressure controller will cause the HPSOV to move to the open or closed position. This pressure enters the valve actuator and acts against a spring and inlet pressure loaded piston. Sufficient servo pressure (10 psi minimum) from the controller is needed to operate the actuator piston and attached links and cranks to open the valve. The valve is spring loaded to the fully closed position if no servo pressure is supplied.

 3.  High Pressure Controller (Fig. 6)
________________________
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 36-11-00
 ALL  ú ú 01P Page 6 ú Feb 10/93
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL

SEE A AIR SUPPLY CONTROL AND TEST UNIT, M7957 P5 PANEL
SEE B
P6 PANEL
FLT COMPT
1 PACKS 2 PACKS 3
NORM NORM NORM
OFF

A A
A
B

OFF OFF
B B
L ISLN R ISLN
VALVE VALVE
WING WING
TAI TAI
APU  AIR SUPPLY CONTROL
SYS SYS  AND TEST UNIT, M7957
SYS SYS ON
FAULT FAULT
FAULT FAULT
VALVE

1 2 3 4
ON ON ON ON
ENGINE
BLEED

OFF OFF OFF OFF
BLEED CONTROL MODULE, M7328
A

E2-4
FWD
MAIN EQUIP CTR B
Bleed Air Control Figure 4
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 36-11-00
 ALL  ú ú 01P Page 7 ú Feb 18/02
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL

HIGH PRESSURESHUTOFF VALVE
SEE A SEE B ACTUATOR ACTUATOR
FWD
PRESSURE HOUSINGTUBE HIGH PRESSURE
TERMINAL A SHUTOFF VALVE
BLOCK
POSITION SWITCHESCLOSED
OPEN/CLOSE
POSITION
SWITCHES

AMBIENT
OPEN ACTUATOR SERVO PRESSURE(FROM HIGH PRESSURECONTROLLER)
VISUAL
POSITION

FROM HIGH
INDICATOR
PRESSURE
TO PRECOOLERMANUAL
BLEED PORT
OPERATION
HEX NUT

HPSOV
VALVE VALVE
INLET  OUTLET
B SCHEMATIC
B

High Pressure Shutoff ValveFigure 5
3
2
1
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 36-11-00
 ALL  ú ú 01P Page 8 ú Feb 18/02
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL

LOW 15TH-STAGE PRESSURE (PHL)HIGH 15TH-STAGE PRESSURE (PHH)
BITEBITE PRESS PRESS SWITCH SWITCH ENGINE GEARBOX
BITE PRESSUREBITE PRESSURE
SWITCH PHL

SWITCH PCHIGH PRESSUREEVACUATEDCONTROLLER
SPRING SEE A ANEROID
SHUTOFFBITE PRESSURESHUTOFF SOLENOID
SOLENOID SWITCH PHH
PH-PC
DIFFERENTIAL
AMBIENT
　
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：747-400 AMM 飞机维护手册 气动系统 PNEUMATIC SYSTEM(26)