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ALL ú ú 01 Page 612 ú Jul 15/96
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
APU SHROUD - DESCRIPTION AND OPERATION
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1. General (Fig. 1)
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A. The APU shroud is a titanium compartment that fully protects the APU power plant. The APU shroud gives the protection from an APU fire and decrease the noise from the APU power plant. The APU shroud includes the upper shroud and the lower shroud. The upper shroud attaches to the airplane structure and holds the forward end of the APU exhaust duct. The upper shroud and the lower shroud connect to one another with the shroud latches on the lower shroud.
2. Upper Shroud (Fig. 1)
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A. The upper shroud is installed in the APU compartment. The upper shroud attaches to the shroud rings. The shroud rings attach to the APU compartment with eight ring mounts. When the APU is removed from the airplane, the upper shroud will stay in the APU compartment. The upper shroud has openings for the fuel lines, air inlet ducts and bleed air duct. The upper shroud has the fittings for the electrical connections and plumbing connections. Three mounting brackets for the APU engine attach to the shroud rings. The fuel heater is installed on the inner surface of the upper shroud.
3. Lower Shroud (Fig. 1)
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A. The lower shroud attaches to the upper shroud with ten shroud latches. The lower shroud has the openings to the filler port for the oil tank and to the overboard exhaust for the APU cooling air. Also, there is an access panel that is removed to read the elapsed time indicator. When the lower shroud is removed, you can get access to do maintenance on the APU control thermostat (Airplanes without the ETC) or the proportional control valve (Airplanes with the ETC), EGT probes, overtemperature control thermocouple, combustor unit, fuel lines, igniter plug, ignition unit, oil tank, oil quantity transmitter, oil line, APU electrical generator, cooling fan, fuel control unit, tachometer generator, starter motor and oil pump.
4. APU Shroud Drains (Fig. 1)
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A. The APU shroud drains remove the extra fuel from the combustion chamber that is not burned during the APU operation. Also, the APU shroud drains remove all the fuel and the oil that leaks from the APU engine. The APU shroud drains have two drain lines, two drain cups, standpipe, drain reservoir and shroud drains.
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
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ALL ú ú 01 Page 1 ú Mar 15/92
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
////////////////////////A / GTCP85-129 SERIES /737-300/400/500/ ENGINES /MAINTENANCE MANUAL ////////////////////////
UPPER SHROUD
CUTOUT HEATER FUEL
FOR THE BLEED AIR DUCT SHROUD RING
LATCH
RING MOUNT
INLET DUCT FOR THE ACCESSORY COOLING AIR
SEE A RING MOUNT
FUEL LINE
INLET LOCK
INLET FLANGE HANDLE
FOR THE ACCESSORY
COOLING AIR FUEL HOSE
SEE B
LATCH
OVERBOARD EXHAUST FOR THE ACCESSORY COOLING AIRDRAIN
LINE
ACCESS PANEL LOWERFOR THE
DRAIN SHROUD
ELAPSED TIME
LINES DRAIN
FWDINDICATOR FITTING
CUTOUT FOR THE OIL
A
FILLER CUP
LOWER SHROUD
STAND PIPE
DRAIN CUPSHROUD DRAIN
DRAIN RESERVIOR DRAIN LINE
DRAIN CUP FWDSEE C
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本文链接地址：737-300 400 500 AMM 飞机维护手册 AIRBORNE AUXILIARY POWER 1(115)
