DOC AIRBUS | AMM A320FOXYGEN STORAGE - DESCRIPTION AND OPERATION
** ON A/C NOT FOR ALL
1. General
The crew oxygen-storage system has a High Pressure (HP) oxygen cylinder which supplies oygen to the flight crew.
The valve assembly is installed on the oxygen cylinder head.
A pressure regulator/transmitter is connected to the valve assembly.
The HP oxygen cylinder and its pressure regulator/transmitter have an overboard discharge system which prevents too much pressure in the HP oxygen cylinder and/or in the Low Pressure (LP) chamber of the pressure regulator/transmitter.
The HP oxygen cylinder is installed on a support that has two quick release clamps in the left part of the avionics compartment between frames 11 and 12.
The crew oxygen-storage system has two High Pressure (HP) oxygen cylinders that operate independently.
The valve assembly is installed on each oxygen cylinder head.
A pressure regulator/transmitter is connected to each valve assembly.
Each HP oxygen cylinder and its pressure regulator/transmitter have an overboard discharge system that operates independently.
An overboard discharge system prevents too much pressure in the HP oxygen cylinders and/or in the Low Pressure (LP) chamber of the pressure regulators/transmitters.
The HP oxygen cylinders supply oxygen to the flight crew. They are installed in the left side of the avionics compartment between frames 11 and 12 for the first oxygen cylinder and between frames 16 and 17 for the second oxygen cylinder.
Each oxygen cylinder is installed on a support that has two quick-release clamps.
** ON A/C NOT FOR ALL The crew oxygen-storage system has a High Pressure (HP) oxygen cylinder which supplies oygen to the flight crew.
The valve assembly is installed on the oxygen cylinder head.
A pressure regulator/transmitter is connected to the valve assembly.
The HP oxygen cylinder and its pressure regulator/transmitter have an overboard discharge system which prevents too much pressure in the HP oxygen cylinder and/or in the Low Pressure (LP) chamber of the pressure regulator/transmitter.
The HP oxygen cylinder is installed on a support that has two quick release clamps in the left part of the avionics compartment between frames 11 and 12.
The crew oxygen-storage system has two High Pressure (HP) oxygen cylinders that operate independently.
The valve assembly is installed on each oxygen cylinder head.
A pressure regulator/transmitter is connected to each valve assembly.
Each HP oxygen cylinder and its pressure regulator/transmitter have an overboard discharge system that operates independently.
An overboard discharge system prevents too much pressure in the HP oxygen cylinders and/or in the Low Pressure (LP) chamber of the pressure regulators/transmitters.
The HP oxygen cylinders supply oxygen to the flight crew. They are installed in the left side of the avionics compartment between frames 11 and 12 for the first oxygen cylinder and between frames 16 and 17 for the second oxygen cylinder.
Each oxygen cylinder is installed on a support that has two quick-release clamps.
2. Component Location
** ON A/C NOT FOR ALL | FIN | FUNCTIONAL DESIGNATION | PANEL | ZONE | ACCESS DOOR | ATA REF |
|---|---|---|---|---|---|
| ** ON A/C ALL | |||||
| 5750HM | CYLINDER-OXYGEN STORAGE | 125 | 35-11-41 | ||
| ** ON A/C NOT FOR ALL | |||||
| 5750HM1 | OXYGEN CYLINDER | 125 | 35-11-41 | ||
| 5750HM2 | OXYGEN CYLINDER | 126 | 35-11-41 | ||
| ** ON A/C ALL | |||||
| 4HT | XMTR/PRESS REG-OXY | 125 | 35-13-15 | ||
| ** ON A/C NOT FOR ALL | |||||
| 4HT2 | PRESS.TRANSM.REGULATO | 126 | 35-13-15 | ||
| ** ON A/C NOT FOR ALL | |||||
| 5769HM | FILL PORT-OXY SYS | 125 | 35-11-42 | ||
| ** ON A/C NOT FOR ALL | |||||
| 5769HM1 | PORT.FILLING ASSY | 123 | 35-11-42 | ||
| 5769HM2 | PORT.FILLING ASSY | 125 | 35-11-42 | ||
| ** ON A/C NOT FOR ALL | |||||
| 5HT | IND-OXY FILLING | 125 | 35-13-21 | ||
| ** ON A/C NOT FOR ALL | |||||
| 5HT1 | IND OXY FILLING | 125 | 35-13-21 | ||
| 5HT2 | IND OXY FILLING | 125 | 35-13-21 | ||
3. System Description
Crew Oxygen Storage - Block Diagram ** ON A/C NOT FOR ALL
Crew Oxygen Storage - Block Diagram ** ON A/C NOT FOR ALL
In the oxygen storage sub-system, the equipment with the LP oxygen-supply solenoid-valve is a part of the oxygen storage sub-system.
For the oxygen storage sub-system, the source supply line receives the LP oxygen from the pressure regulator/transmitter and supplies it to the LP oxygen-supply solenoid-valve.
The LP oxygen-supply solenoid-valve has an electrical shutoff function between the oxygen supply sub-system and the downstream crew-distribution sub-system.
The pressure regulator/transmitter decreases the HP oxygen from the HP oxygen cylinder to a lower breathing level and to the LP chamber of each pressure regulator/transmitter (Ref. AMM D/O 35-13-00-00).
An overboard discharge indicator is connected to the crew oxygen-storage system through an overboard discharge line to release unwanted HP oxygen and/or LP oxygen.
In the applicable oxygen storage sub-system, the equipment with the LP oxygen-supply solenoid-valve is a part of the oxygen storage sub-system.
For the oxygen storage sub-system, a fully isolated source supply line receives the LP oxygen from the pressure regulator/transmitter and supplies it to the LP oxygen-supply solenoid-valve.
The LP oxygen-supply solenoid-valve has an electrical shutoff function between the oxygen supply sub-system and the downstream crew-distribution sub-system.
The pressure regulator/transmitter decreases the HP oxygen from the HP oxygen cylinder to a lower breathing level and to the LP chamber of the pressure regulator/transmitter (Ref. AMM D/O 35-13-00-00).
An overboard discharge indicator is connected to crew oxygen-storage system through an overboard discharge line to release unwanted HP oxygen and/or LP oxygen.
The below information about the crew oxygen-storage system is applicable only to the aircraft which has two oxygen cylinders:
** ON A/C NOT FOR ALL Crew Oxygen Storage - Block Diagram ** ON A/C NOT FOR ALL Crew Oxygen Storage - Block Diagram ** ON A/C NOT FOR ALL For the oxygen storage sub-system, the source supply line receives the LP oxygen from the pressure regulator/transmitter and supplies it to the LP oxygen-supply solenoid-valve.
The LP oxygen-supply solenoid-valve has an electrical shutoff function between the oxygen supply sub-system and the downstream crew-distribution sub-system.
The pressure regulator/transmitter decreases the HP oxygen from the HP oxygen cylinder to a lower breathing level and to the LP chamber of each pressure regulator/transmitter (Ref. AMM D/O 35-13-00-00).
An overboard discharge indicator is connected to the crew oxygen-storage system through an overboard discharge line to release unwanted HP oxygen and/or LP oxygen.
In the applicable oxygen storage sub-system, the equipment with the LP oxygen-supply solenoid-valve is a part of the oxygen storage sub-system.
For the oxygen storage sub-system, a fully isolated source supply line receives the LP oxygen from the pressure regulator/transmitter and supplies it to the LP oxygen-supply solenoid-valve.
The LP oxygen-supply solenoid-valve has an electrical shutoff function between the oxygen supply sub-system and the downstream crew-distribution sub-system.
The pressure regulator/transmitter decreases the HP oxygen from the HP oxygen cylinder to a lower breathing level and to the LP chamber of the pressure regulator/transmitter (Ref. AMM D/O 35-13-00-00).
An overboard discharge indicator is connected to crew oxygen-storage system through an overboard discharge line to release unwanted HP oxygen and/or LP oxygen.
The below information about the crew oxygen-storage system is applicable only to the aircraft which has two oxygen cylinders:
- An overboard discharge indicator is connected to the crew oxygen-storage system through an overboard discharge line to release unwanted HP oxygen and/or LP oxygen.
- The overboard discharge line is fully isolated from the other one.
- The overboard discharge line is connected to the HP safety outlet of each oxygen cylinder and to the LP chamber of each pressure regulator/transmitter (Ref. AMM D/O 35-13-00-00).
- Each system is mechanically isolated from the other system. Thus, if there is a malfunction in one of the systems, this will not have an effect on the other system.
- In the cockpit, on overhead control and indicating panel 21VU, the CREW SUPPLY pushbutton switch is for the two oxygen systems. Its function is to start or close the two systems at the same time.
4. Component Description
(1) The oxygen cylinder(s) has(have) the properties that follow:
(a) The oxygen cylinder(s) is(are) made of composite material.
(b) The oxygen cylinder(s) has(have) a capacity of 2183 l (576.68 USgal) (77.1 cubic feet) at a pressure of 1850 psi (127.55 bar).
(2) The high pressure oxygen cylinder is made of steel material. The oxygen cylinder has a capacity of 3256 l (860.14 USgal) (NTPD: Normal Temperature Pressure Dry) at a pressure of 127.55 bar (1850 psi).
(3) The cylinder head has a valve assembly which is made of these components:
(a) A manual slow-opening ON/OFF valve with a metal seat and poppet, to decrease the explosion hazard. The valve is used during the replacement of the cylinder and to isolate the cylinder if there is a leak in the oxygen system.
(b) A direct-reading pressure gage which gives an indication of the cylinder high-pressure, independent of the open or closed position of the manual valve.
(c) A high-pressure safety outlet with a discharge indicator. The discharge indicator is a frangible disc that breaks at a pressure of 172.5 to 191.5 bar (2500 to 2775 psig). The oxygen is discharged overboard.
(1) The pressure regulator/transmitter has these properties:
(a) It decreases the oxygen pressure from the HP oxygen cylinder/valve assembly to a lower, breathing level in the distribution circuit.
(b) When the source supplies a pressure between 100 psi (6.89 bar) and 1850 psi (127.55 bar), the oxygen flows through the outlet at a pressure between 65 psi (4.48 bar) and 94 psi (6.48 bar).
(c) The maximum outlet flow is 500 l.min (132.08 USgal.mn).
(2) The pressure regulator/transmitter has the components that follow:
(a) A pressure sensor installed on the HP chamber which sends an electrical signal of the oxygen pressure to the ECAM system in the cockpit.
(b) A lower-pressure safety outlet with an integrated LP relief valve to prevent unwanted pressure flows into the distribution circuit. The LP relief valve opens at a pressure between 109 psi (7.5 bar) and 116 psi (8.0 bar) and releases the pressure to the overboard discharge line.
(c) A filling connector installed on the HP chamber. A plug is attached to this filling connector with a lanyard. It is installed when the filling line is not connected.
C. Safety System
The low-pressure safety outlet has an integrated relief valve. This stops the low-pressure oxygen supply to a maximum of 12 bar (175 psig). The oxygen released by the low-pressure safety outlet is discharged overboard by a safety system.
The high-pressure safety outlet on the oxygen cylinder head and the low pressure safety outlet on the pressure regulator/transmitter are connected to a discharge indicator on the fuselage skin (near the access door 812). The discharge indicator is a green blow-out disc that is from the outerside of the aircraft. This disc will blow out at a pressure of 2.8 to 6.9 bar (40 to 100 psig) to show a yellow indicator. This shows that the oxygen is discharged.
The low-pressure safety outlet has an integrated relief valve. This stops the low-pressure oxygen supply to a maximum of 12 bar (175 psig). The oxygen released by the low-pressure safety outlet is discharged overboard by a safety system.
The high-pressure safety outlet on the oxygen cylinder head and the low pressure safety outlet on the pressure regulator/transmitter are connected to a discharge indicator on the fuselage skin (near the access door 812). The discharge indicator is a green blow-out disc that is from the outerside of the aircraft. This disc will blow out at a pressure of 2.8 to 6.9 bar (40 to 100 psig) to show a yellow indicator. This shows that the oxygen is discharged.
D. Replenishment of the Oxygen Source
Crew Oxygen Storage - Block Diagram ** ON A/C NOT FOR ALL
Crew Oxygen Storage - Block Diagram ** ON A/C NOT FOR ALL
If the oxygen cylinder(s) is (are) empty, you can fill it (them) through its (their) filling port(s) with an external filling source.
Crew Oxygen Storage - Block Diagram ** ON A/C NOT FOR ALL Crew Oxygen Storage - Block Diagram ** ON A/C NOT FOR ALL E. External Filling Connection
Crew Oxygen Storage - Block Diagram ** ON A/C NOT FOR ALL
Crew Oxygen Storage - Block Diagram ** ON A/C NOT FOR ALL
The external filling connection permits filling of the oxygen cylinder without the removal of the cylinder from the aircraft. The external filling connection is made of the components below:
Crew Oxygen Storage - Block Diagram ** ON A/C NOT FOR ALL Crew Oxygen Storage - Block Diagram ** ON A/C NOT FOR ALL - A filling connector with a filter. The filter prevents the entrance of moisture or dust into the oxygen system.
- A filling connector cap with a relief valve. The relief valve releases some oxygen pressure of more than 6.9 bar (100 psi) if there is a leak in the check valve of the pressure regulator/transmitter.
- A flexible hose connects the filling connection to the pressure regulator/transmitter.
- A pressure gage to indicate the pressure inside the oxygen cylinder during filling. The pressure gage has a two color scale with graduations: 0 bar (0.00 psi) to 5.9 bar (86 psi) is red, 5.9 bar (85.5722 psi) to 138 bar (2000 psi) is green.
- The pressure for operation is 0 bar (0.00 psi) to 140 bar (2030 psi). The filling rate is 0 to 500 l/min (0 to 17.65 (cubic feet)/min) (NTPD).