S 434-010

 (2)  
Remove the protective caps or the plugs from the lines, fittings or ports.

 S 214-035

 (3)  
Examine the fitting (threads) to make sure they are clean.

 S 424-011

 (4)  
Install the pressure reducer.

 (a)  
Put a metal seal with the flat face in the direction of the coupling assembly.

 (b)  
Put the ball face in the direction of the high pressure end of the pressure reducer.

 CAUTION: MAKE SURE YOU TIGHTEN THE PRESSURE REDUCER AS INDICATED.
_______ THE OXYGEN CYLINDER CAN LEAK AFTER THE INSTALLATION OF THE COUPLING ASSEMBLY. USE A WRENCH ON THE LEG FLATS OF THE COUPLING ASSEMBLY TO TIGHTEN THE COUPLING ASSEMBLY. IF YOU DO NOT THE COUPLING ASSEMBLY CAN BREAK.
 (c)  
Install pressure reducer to coupling assembly, and tighten to a torque of approximately 300 pound-inches.

 (d)  
Continue to tighten until a sharp increase in torque occurs.

 NOTE: The sharp increase in pressure indicates the parts
____ are in flush contact with the seal. The pressure reducer inlet and outlet ports are different in size. The pressure reducer can only be installed with flow in the correct direction.
 CAUTION: MAKE SURE THE UNION IS TIGHTENED AS INDICATED, THE OXYGEN
_______ CYLINDER CAN LEAK AFTER THE INSTALLATION OF THE COUPLING. ASSEMBLY. THIS CAN CAUSE DAMGE OF THE AIRPLANE EQUIPMENT.
 (e)  Put the metal seal with flat face in the direction of the union and ball face in the direction of the pressure reducer.
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 35-21-12
 ALL  ú ú 05 Page 405 ú Oct 18/00
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A 747-400 MAINTENANCE MANUAL
 (f) (g)  Install the union in the medium pressure end of the pressure reducer and tighten the union to a torque of approximately 300 pound-inches.Continue to tighten until a sharp increase in torque occures.
 NOTE:____ This sharp increase in pressure indicates the parts are in flush contact with the seal.

 S 434-012
 (5)  Install the coupling assembly.
 (a)  
Put the assembly which includes the coupling assembly, pressure transducer, and pressure reducer in position with cylinder nut.

 (b)  
Make sure this assembly with the coupling to cylinder nut in alignment with the cylinder port.

 (c)  
Tighten the coupling assembly to cylinder nut to a torque of 650 to 700 pound-inches.

 (d)  
Tighten the B-nut on the pressure reducer outlet.

 S 434-013
 (6)  Connect the electrical connector on the prewsure transducer.
 S 864-025
 WARNING:_______OPEN THE SHUTOFF VALVE ON A OXYGEN CYLINDER SLOWLY. IF NOT, HIGH TEMPERATURES CAN OCCUR WHICH CAN START AN IGNITION WITH THE OXYGEN. THIS CAN CAUSE INJURY TO PERSONS AND DAMAGE TO THE AIRPLANE AND EQUIPMENT.
 CAUTION: DO NOT TIGHTEN THE SHUTOFF VALVE ON A OXYGEN CYLINDER MORE THAN
_______ 25 POUND-INCHES. THIS CAN CAUSE DAMAGE TO THE SHUTOFF VALVE.
 (7)  Open the shutoff valve on an oxygen cylinder:
 (a)  Slowly turn the shutoff valve until it is fully open.
 NOTE: The shutoff valve can be closed by hand which is
____
 equivalent to 25 pound-inches.

 (b)  
Close the shutoff valve one-fourth of a turn.

 (c)  
Install a lockwire on the shutoff valve.

 S 794-015
 (8)  Do a check of the connections for leaks with the leak detection compound.
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 35-21-12
 ALL  ú ú 04 Page 406 ú Oct 18/00
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
 S 164-036
 (9)  Rub the leak detection compound off with a clean cloth immediately after you do the check.
 S 864-032
 WARNING: OPEN THE SHUTOFF VALVE ON THE REMAINING OXYGEN CYLINDERS
　
中國(guó)航空網(wǎng) www.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：747-400 AMM 飛機(jī)維護(hù)手冊(cè) 氧氣 OXYGEN(89)