DOC AIRBUS | AMM A320FNitrogen Filling of the Yellow Hydraulic System, Brake Pressure Accumulator
TASK 12-14-32-614-002-A
Nitrogen Filling of the Yellow Hydraulic System, Brake Pressure Accumulator
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
B. Consumable Materials
C. Referenced Information
3. Job Set-up
Subtask 12-14-32-941-052-A
Subtask 12-14-32-420-050-A
Subtask 12-14-32-865-051-A
[Rev.10 from 2021]
2026.04.01 12:31:51 UTC
Nitrogen Filling of the Yellow Hydraulic System, Brake Pressure Accumulator
WARNING:
PUT THE SAFETY DEVICES AND THE WARNING NOTICES IN POSITION BEFORE YOU START A TASK ON OR NEAR:
- THE FLIGHT CONTROLS
- THE FLIGHT CONTROL SURFACES
- THE LANDING GEAR AND THE RELATED DOORS
- COMPONENTS THAT MOVE.
WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
1. Reason for the JobSelf explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
| REFERENCE | QTY | DESIGNATION |
|---|---|---|
| No specific | AR | SAFETY BARRIER(S) |
| No specific | AR | SAFETY CLIP - CIRCUIT BREAKER |
| No specific | 1 | WARNING NOTICE(S) |
| No specific | Torque wrench: range to between 0.11 and 0.06 m.daN (9.73 and 5.31 lbf.in )  | |
| No specific | Torque wrench: range to between 0.68 and 0.56 m.daN (60.18 and 49.56 lbf.in ) | |
| 98F29103500000 | 1 | FILL UNIT-NITROGEN |
| REFERENCE | DESIGNATION |
|---|---|
| (Material No.14CCB6) | Testing Medium-Leak Detection - Oxygen System |
| (Material No.14VGC1) | Individual Compound-- Nitrogen Gaseous |
| REFERENCE | DESIGNATION |
|---|---|
| TASK 29-10-00-864-002-A | Depressurize the Yellow Hydraulic System |
Subtask 12-14-32-941-052-A
A. Safety Precautions
(1) Put the SAFETY BARRIER(S) in position.
(2) Put a WARNING NOTICE(S) on panel 198CB to tell persons not to pressurize the Yellow hydraulic system.
Subtask 12-14-32-860-052-A (1) Put the SAFETY BARRIER(S) in position.
(2) Put a WARNING NOTICE(S) on panel 198CB to tell persons not to pressurize the Yellow hydraulic system.
B. Aircraft Maintenance Configuration
(1) On panel 400VU, make sure that the L/G control-lever is in the DOWN position.
(2) On panel 110VU, make sure that the GRAVITY GEAR EXT handle is in the stowed position.
(3) Make sure that the pressure in the brake accumulator of the Yellow hydraulic system is released (Ref. AMM TASK 29-10-00-864-002).
Subtask 12-14-32-865-050-A (1) On panel 400VU, make sure that the L/G control-lever is in the DOWN position.
(2) On panel 110VU, make sure that the GRAVITY GEAR EXT handle is in the stowed position.
(3) Make sure that the pressure in the brake accumulator of the Yellow hydraulic system is released (Ref. AMM TASK 29-10-00-864-002).
C. Open, safety and tag this(these) circuit breaker(s):
4. Procedure| PANEL | DESIGNATION | FIN | LOCATION |
|---|---|---|---|
| ** ON A/C NOT FOR ALL | |||
| 121VU | HYDRAULIC/HYD POWER/Y | 3803GX | N30 |
| ** ON A/C ALL | |||
| 121VU | HYDRAULIC/Y HYD/PUMP ENG2/MONG | 3700GD | Q37 |
| 121VU | HYDRAULIC/Y HYD/PUMP ENG2/CTL | 3701GD | Q36 |
| ** ON A/C NOT FOR ALL | |||
| 121VU | HYDRAULIC/HYD POWER/Y | 3803GX | N31 |
| ** ON A/C ALL | |||
| 123VU | Y HYD/ELEC/PUMP | 3802GX | AB06 |
| 123VU | Y HYD/ELEC/ELEC PUMP/NORM | 3801GX | AB03 |
Subtask 12-14-32-420-050-A
A. Installation of the 98F29103500000 FILL UNIT-NITROGEN on the 6L Brake Accumulator
(2) Connect the supply hose (D) to the nitrogen cylinder (F).
(3) Remove the cap (4) from the charging valve (1).
(4) Connect the filling hose (A) to the charging valve (1).
(5) Make sure that the nut (3) of the charging valve (1) is closed.
(6) Slowly open the control valves (B) and (J) on the three-way valve (C).
(7) Open the control valve (G) on the nitrogen cylinder (F). Blow nitrogen through the 98F29103500000 FILL UNIT-NITROGEN to bleed the system.
(8) Close the control valve (B) and then close the control valve (J) on the three-way valve (C).
Subtask 12-14-32-614-052-A WARNING:
DO NOT LET COMPRESSED GAS TOUCH YOUR SKIN. THE GAS CAN GO THROUGH THE SKIN AND MAKE BUBBLES IN THE BLOOD. THIS CONDITION CAN KILL YOU.
(1) Make sure that the hydraulic pressure in the 6L brake accumulator of the Yellow hydraulic system is released. (2) Connect the supply hose (D) to the nitrogen cylinder (F).
(3) Remove the cap (4) from the charging valve (1).
(4) Connect the filling hose (A) to the charging valve (1).
(5) Make sure that the nut (3) of the charging valve (1) is closed.
(6) Slowly open the control valves (B) and (J) on the three-way valve (C).
(7) Open the control valve (G) on the nitrogen cylinder (F). Blow nitrogen through the 98F29103500000 FILL UNIT-NITROGEN to bleed the system.
(8) Close the control valve (B) and then close the control valve (J) on the three-way valve (C).
B. Nitrogen Filling of the 6L Brake Accumulator of the Yellow Hydraulic System
(3) Set the pressure regulator (E) to the correct pressure on the pressure gage (H), as shown on:
Brake Accumulator - Pressure Graph ** ON A/C NOT FOR ALL
Brake Accumulator - Pressure Graph ** ON A/C NOT FOR ALL
Yellow System Brake-Accumulator - Pressure Graph ** ON A/C NOT FOR ALL
(4) Loosen the nut (3) of the charging valve (1).
(6) Make sure that the pressure on the pressure gage (2) agrees with:
Brake Accumulator - Pressure Graph ** ON A/C NOT FOR ALL
Brake Accumulator - Pressure Graph ** ON A/C NOT FOR ALL
Yellow System Brake-Accumulator - Pressure Graph ** ON A/C NOT FOR ALL
(7) Wait for five minutes (with the pressure regulated supply connected and the control valve (J) open) to let the brake accumulator temperature and pressure become stable.
(8) Close the control valve (J). Make sure that the pressure on the pressure gage (2) is correct and stable.
(9) Make sure that the pressure on the pressure gage (2) is:
(11) If the pressure is more than plus 3.45 bar (50 psi) from the correct pressure, then decrease the pressure as follows:
(a) Open the control valve (B) until the pressure is decreased to the correct value.
(b) Close the control valve (B) when the pressure is correct.
(12) If the pressure is less than minus 3.45 bar (50 psi) from the correct pressure, do steps (4) thru (8) again.
(13) When the pressure is correct and stable, TORQUE the nut (3) of the charging valve (1) to between 0.68 and 0.56 m.daN (60.18 and 49.56 lbf.in ).
Subtask 12-14-32-020-050-A WARNING:
DO NOT LET COMPRESSED GAS TOUCH YOUR SKIN. THE GAS CAN GO THROUGH THE SKIN AND MAKE BUBBLES IN THE BLOOD. THIS CONDITION CAN KILL YOU.
(1) Make sure that the hydraulic pressure in the brake accumulator of the Yellow hydraulic system is released. NOTE: When you fill the Yellow hydraulic system and the brake accumulator, you must use Individual Compound-- Nitrogen Gaseous (Material No.14VGC1) . This will make sure that the oxygen level stays low.
(2) Wait for 25 minutes to let the pressure become stable and get a more accurate value (temperature compensation of the 6L brake accumulator). (3) Set the pressure regulator (E) to the correct pressure on the pressure gage (H), as shown on:
- The pressure graph for the brake-accumulator gas interface/neck temperature.
Brake Accumulator - Pressure Graph ** ON A/C NOT FOR ALL Brake Accumulator - Pressure Graph ** ON A/C NOT FOR ALL Yellow System Brake-Accumulator - Pressure Graph ** ON A/C NOT FOR ALL WARNING:
WHEN YOU FILL THE BRAKE ACCUMULATOR WITH NITROGEN, DO NOT TOUCH THE CHARGING VALVE. THE VALVE WILL BECOME VERY COLD AND CAN CAUSE YOUR FINGERS TO FREEZE.
(5) Carefully open the control valve (J) until you get a slow and stable charging rate (less than 50 bar (725 psi) per minute). Fill the brake accumulator to the correct pressure for the brake-accumulator gas interface/neck temperature.(6) Make sure that the pressure on the pressure gage (2) agrees with:
- The pressure values of the graph for the brake-accumulator gas interface/neck temperature.
Brake Accumulator - Pressure Graph ** ON A/C NOT FOR ALL Brake Accumulator - Pressure Graph ** ON A/C NOT FOR ALL Yellow System Brake-Accumulator - Pressure Graph ** ON A/C NOT FOR ALL (8) Close the control valve (J). Make sure that the pressure on the pressure gage (2) is correct and stable.
(9) Make sure that the pressure on the pressure gage (2) is:
- Not more than plus 3.45 bar (50 psi) from the correct pressure
- Not less than minus 3.45 bar (50 psi) from the correct pressure.
(11) If the pressure is more than plus 3.45 bar (50 psi) from the correct pressure, then decrease the pressure as follows:
(a) Open the control valve (B) until the pressure is decreased to the correct value.
(b) Close the control valve (B) when the pressure is correct.
(12) If the pressure is less than minus 3.45 bar (50 psi) from the correct pressure, do steps (4) thru (8) again.
(13) When the pressure is correct and stable, TORQUE the nut (3) of the charging valve (1) to between 0.68 and 0.56 m.daN (60.18 and 49.56 lbf.in )
. NOTE: You must not use too much force when you tighten the nut (3) of the charging valve (1). Leakage from the charging valve (1) can occur if the valve seat is damaged.
(14) Make sure that the control valves (B) and (J) are closed. C. Removal of the 98F29103500000 FILL UNIT-NITROGEN from the 6L Brake Accumulator
(2) Slowly open the control valves (B) and (J) on the three-way valve (C) to remove the nitrogen from the 98F29103500000 FILL UNIT-NITROGEN.
(3) Close the control valves (B) and (J) on the three-way valve (C).
(4) Remove the filling hose (A) from the charging valve (1) of the brake accumulator assembly.
(5) Use Testing Medium-Leak Detection - Oxygen System (Material No.14CCB6) to do a leak check of the charging valve (1) on the brake accumulator assembly.
(6) Install the cap (4) on the charging valve (1).
(7) TORQUE the cap (4) to between 0.11 and 0.06 m.daN (9.73 and 5.31 lbf.in ).
5. Close-upWARNING:
DO NOT LET COMPRESSED GAS TOUCH YOUR SKIN. THE GAS CAN GO THROUGH THE SKIN AND MAKE BUBBLES IN THE BLOOD. THIS CONDITION CAN KILL YOU.
(1) Make sure the control valve (G) on the nitrogen cylinder (F) is closed. (2) Slowly open the control valves (B) and (J) on the three-way valve (C) to remove the nitrogen from the 98F29103500000 FILL UNIT-NITROGEN.
(3) Close the control valves (B) and (J) on the three-way valve (C).
(4) Remove the filling hose (A) from the charging valve (1) of the brake accumulator assembly.
(5) Use Testing Medium-Leak Detection - Oxygen System (Material No.14CCB6) to do a leak check of the charging valve (1) on the brake accumulator assembly.
(6) Install the cap (4) on the charging valve (1).
(7) TORQUE the cap (4) to between 0.11 and 0.06 m.daN (9.73 and 5.31 lbf.in )
. Subtask 12-14-32-865-051-A
A. Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s):
Subtask 12-14-32-942-054-A | PANEL | DESIGNATION | FIN | LOCATION |
|---|---|---|---|
| ** ON A/C NOT FOR ALL | |||
| 121VU | HYDRAULIC/HYD POWER/Y | 3803GX | N30 |
| ** ON A/C ALL | |||
| 121VU | HYDRAULIC/Y HYD/PUMP ENG2/MONG | 3700GD | Q37 |
| 121VU | HYDRAULIC/Y HYD/PUMP ENG2/CTL | 3701GD | Q36 |
| ** ON A/C NOT FOR ALL | |||
| 121VU | HYDRAULIC/HYD POWER/Y | 3803GX | N31 |
| ** ON A/C ALL | |||
| 123VU | Y HYD/ELEC/PUMP | 3802GX | AB06 |
| 123VU | Y HYD/ELEC/ELEC PUMP/NORM | 3801GX | AB03 |
B. Removal of Equipment
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Remove the SAFETY BARRIER(S).
(3) Remove the WARNING NOTICE(S).
(4) Remove the access platform(s).
(5) Remove the ground support and maintenance equipment, the special and standard tools and all other items.
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Remove the SAFETY BARRIER(S).
(3) Remove the WARNING NOTICE(S).
(4) Remove the access platform(s).
(5) Remove the ground support and maintenance equipment, the special and standard tools and all other items.