W DOC AIRBUS | AMM A320F

Repair of Hydraulic Tubes with RYNGLOK R8 Unions

TASK 20-23-11-300-007-A
Repair of Hydraulic Tubes with RYNGLOK R8 Unions

1. Reason for the Job
This is an approved repair procedure for hydraulic tubes.
NOTE: This procedure is applicable to:
  • Titanium-alloy (Ti-3Al-2.5V) tubes ref. ABS5004, sizes -04 to -16
  • Corrosion-resistant steel (21.6.9) tubes ref. ASNA3288, sizes -04 to -24
  • Aluminum-alloy (6061-T6) tubes ref. ASNA3410 and DAN40, sizes -04 to -16 and -24.
NOTE: For hydraulic tubes installed in the fuel tanks, in the pylon box structure (between RIB 5 and RIB 10) and in the pressurized area, only the permanent fittings repair solution is permitted.
NOTE: This repair procedure is not applicable to:
  • Hydraulic tubes of the engines
  • Coiled tubes
  • Hydraulic tubes installed on the landing gear legs.
2. Job Set-up Information
 A. Fixtures, Tools, Test and Support Equipment
REFERENCE
QTY
DESIGNATION
No specific
AR
CLOTH-EMERY (GRADE 400)
No specific
AR
SCOTCHBRITE
RCSK8-02S013
1
RYNGLOK UNIVERSAL TOOL KIT
 B. Consumable Materials
REFERENCE
DESIGNATION
(Material No.04CMA2)
Wash Primer_- - Structure
(Material No.04EAC2)
Primer Polyurethane Paint_- Corrosion Inhibiting Structure
(Material No.08BAA9)
Non Aqueous Cleaner-General - -
(Material No.10ABC1)
Surface Pretreatment-Light Alloys Chemical Conversion Yellow -
(Material No.14SBA1)
Textile-Lint free Cotton -
 C. Referenced Information
REFERENCE
DESIGNATION
TASK 12-12-29-611-001-A
Fill the Hydraulic Fluid Reservoir with a Hand Pump
TASK 12-12-29-611-002-A
Fill the Hydraulic Fluid Reservoir with a Hydraulic Service Cart
TASK 20-23-11-200-001-A
Permitted Damage and Defects on Hydraulic Tubing
TASK 20-23-11-917-003-A
Cutting and Deburring of Hydraulic Tubes
TASK 29-00-00-864-001-A
Put the Related Hydraulic System in the Depressurized Configuration before Maintenance Action
TASK 29-00-00-870-001-A
Bleeding Procedure of the Green Hydraulic System Upstream of the Engine Pump
TASK 29-00-00-870-002-A
Bleeding Procedure of the Green Hydraulic System Upstream of the PTU
TASK 29-00-00-870-003-A
Bleeding Procedure of the Green Hydraulic System Downstream of the Engine Pump
TASK 29-00-00-870-004-A
Bleeding Procedure of the Yellow Hydraulic System Upstream of the Engine Pump
TASK 29-00-00-870-005-A
Bleeding Procedure of the Yellow Hydraulic System Upstream of the PTU
TASK 29-00-00-870-006-A
Bleeding Procedure of the Yellow Hydraulic System Upstream of the Yellow E-Pump
TASK 29-00-00-870-007-A
Bleeding Procedure of the Yellow Hydraulic System Downstream of the Engine Pump
TASK 29-00-00-870-008-A
Bleeding Procedure of the Blue Hydraulic System Upstream of the Blue E-Pump
TASK 29-00-00-870-009-A
Bleeding Procedure of the Blue Hydraulic System Downstream of the Blue E-Pump
TASK 29-00-00-910-002-A
Safety Procedures of the Hydraulic System
TASK 29-10-00-863-001-A
Pressurize the Green Hydraulic System with a Hydraulic Ground Power-Cart
TASK 29-10-00-863-002-A
Pressurize the Yellow Hydraulic System with a Hydraulic Ground Power-Cart
TASK 29-10-00-863-003-A
Pressurize the Blue Hydraulic System with a Hydraulic Ground Power-Cart
TASK 29-10-00-863-003-A-01
Pressurize the Blue Hydraulic System with the Blue Electric Pump
TASK 29-14-00-614-001-A
Depressurization of the Hydraulic Reservoirs
TASK 29-14-00-614-002-A
Pressurization of the Hydraulic Reservoirs through the Ground Connector
TASK 29-14-00-614-002-A-01
Pressurization of the Hydraulic Reservoirs with the Auxiliary Power Unit (APU)
TASK 29-23-00-863-001-A
Pressurize the Green Hydraulic System from the Yellow Hydraulic System through the PTU with the Electric Pump
TASK 29-23-00-863-002-A
Pressurize the Yellow Hydraulic System from the Green Hydraulic System through the PTU with the Ground Service Cart
TASK 32-42-00-870-001-A
Bleeding of the Normal Braking at the Brake Units
TASK 32-43-00-612-001-A
Filling and Bleeding of the Low Pressure Control System of the Alternate Braking
TASK 32-43-00-612-001-A-01
Filling and Bleeding of the Low Pressure Control System of the Alternate Braking using Green Reservoir fluid
TASK 32-43-00-870-002-A
Bleeding of the High Pressure Alternate Braking System
F RYNGLOK installation Tooling
F Union Assemblies
F Tubing Repair
F Tube End Dimension and Marking
F Union Installation
3. Job Set-up
Subtask 20-23-11-917-110-A
A. General
Use this approved repair procedure to repair hydraulic tubes made of 21.6.9 corrosion-resistant steel, 6061-T6 aluminum alloy or Ti 3AL 2.5V titanium alloy.
NOTE: You can use the RYNGLOK R8 Unions repair procedure to repair tubes installed with HARRISON fittings.
To repair the tubing with the RYNGLOK R8 Unions, you must:
  • Cut the tube,
  • Deburr the tube,
  • Make the marks for tube insertion,
  • Put the swaging tool into position,
  • Swage the tube,
  • Do a check of the tube joint.
Subtask 20-23-11-860-055-A
B. Safety Precautions
   (1) Obey the safety procedures of the hydraulic system (Ref. AMM TASK 29-00-00-910-002).
   (2) Make sure that the related hydraulic reservoirs and the related hydraulic systems are depressurized (Ref. AMM TASK 29-00-00-864-001) and (Ref. AMM TASK 29-14-00-614-001)
4. Procedure
Subtask 20-23-11-917-078-A
A. Equipment
F RYNGLOK installation Tooling
   (1) For the installation of RYNGLOK R8 unions, we recommend that you use the RCSK8-02S013 RYNGLOK UNIVERSAL TOOL KIT, that includes:
  • The swage tools
  • A cutting and deburring tool kit
  • The marking gages
  • A marking pen
  • The inspection gages
  • A hand pump
     (a) Swage tool
NOTE: There are two types of swage tools: old generation and new generation. To swage the unions, you can use the old-generation tools or the new-generation tools.
       1 Old-generation swage tools.
  • RTST(X)-01-SIZE standard swage tool
    This tool pushes the union ring onto the union body to make the swage.
  • RTST(X)R-01-SIZE reversed swage tool
    This tool pulls the union ring onto the union body to make the swage. You can use this tool to swage the unions where access is not easy:
    - At or near a bulkhead or an adjacent fitting
    - When you cannot use the standard tool.
  • RTST(X)R-51-SIZE special reversed tool
    You must use the special reversed tool where there is an opposite fitting end or forging body size larger than the dash size of the fitting end to be swaged.
    This special reversed tool has a colored band and the required pressures are identified on the tool body.
       2 New-generation swage tool
  • RTST(X)-02-SIZE push/pull swage tool
    This new-generation tool replaces the standard (push) and reversed (pull) tools for easier installation especially in areas where access is not easy.
     (b) Pressure pump
The pump can be:
  • A hand pump, AEROQUIP P/N 10-00420A
  • A foot-operated air/hydraulic intensifier, AEROQUIP P/N 10-00401A
  • A switch-operated air/hydraulic intensifier, AEROQUIP P/N 10-00402.
     (c) RTSGO-51-SIZE inspection gages
Use these tools to make sure that the swage is correct (full movement of the ring).
     (d) RTSGO-01-SIZE marking gages
Use these tools to make installation marks on the tubes.
   (2) Union assemblies
Before you start the installation, make sure that you use the correct union assemblies.
F Union Assemblies
Subtask 20-23-11-917-079-A
B. Tubing Repair
F Tubing Repair
   (1) Single-union repair
You can use a single-union repair if the length of the defect is in the specified limits (L max).
There are two methods for a single-union repair:
     (a) Method 1: You remove (cut out) the part of the tube that has the defect.
     (b) Method 2: You cut through the center of the defect.
NOTE: This is not the best method because, in some conditions, the defect can cause damage to the sealing surface of the union.
If you use this method, you must be careful:
  • To cut the tube in the center of the defect
  • To put the union in the center between the installation marks.
   (2) Two-union repair
     (a) You must use a two-union repair when the length of the defect is more than the specified limits (L max).
You remove (cut out) the part of the tube that has the defect. There is a minimum length of tube (M min) that you must remove.
You replace the removed part of tube with:
  • An equal or smaller (but nearly the same) length of equivalent tube
  • Two RYNGLOK unions.
   (3) Swage near a bend
There must be a minimum length (N min) of straight tube to swage near a bend.
Subtask 20-23-11-917-080-A
C. Preparation
F Tube End Dimension and Marking
   (1) Tube cutting and deburring
   (2) Preparation of the painted tube ends
It is necessary to remove paint from a minimum length (Dim. B) at the ends of the painted tube.
     (a) Remove paint with CLOTH-EMERY (GRADE 400) along the dim. B
Make sure that you do not cause scratches on the tube when you remove the paint.
   (3) Make sure that all the tube ends are in the correct condition and agree with the tube dimension specifications (Ref. AMM TASK 20-23-11-200-001).
   (4) Clean all the tube ends with a Textile-Lint free Cotton - (Material No.14SBA1) and Non Aqueous Cleaner-General - - (Material No.08BAA9) .
NOTE: Make sure that the cleaning agent does not go in the tube.
   (5) Make the marks on the tubes.
     (a) Get the correct size marking gage
F RYNGLOK installation Tooling
       1 Put the applicable marking gage on each tube end.
Make the position and the inspection marks through the gage windows.
We recommend that you use the permanent-ink felt-tipped pen included in RCSK8-02S013 RYNGLOK UNIVERSAL TOOL KIT.
Subtask 20-23-11-917-081-A
D. Union Installation
F Union Installation
   (1) Put the union in position:
     (a) Move the union on the tube ends and put the edge of the unswaged ring on the position mark.
The edge of the ring must be between the two ends of the position mark.
The length of the position mark gives the permitted tolerance for the position of the ring.
   (2) Union assembly
     (a) Get the correct size tool.
F RYNGLOK installation Tooling
NOTE: The color code of the coupling ring must agree with the color of the movable jaw on the swaging tool.
     (b) Connect the flexible hose between the pump and the swaging tool.
     (c) Align the assembly tool to one leg of the union, with the ring in the movable jaw of the tool and the front opening of the tool against the union body.
NOTE: When you use the reversed tool, the union body is in the tool jaw and the front opening is against the ring.
NOTE: When you use size -20 and -24 swage tools, make sure that the swage bridge (connected to the tool by a lanyard) is in the correct position:
  • The arrow on the swage bridge must point to the front of the tool,
  • The swage tool detents must hold the swage bridge when the union is engaged in the tool
    (the swage tool detents make a click when the swage bridge becomes flush on the top of the tool).
NOTE: For the standard swage tool, you must engage the swage bridge in the tool body.
For the reversed tool, you must engage the swage bridge in the movable jaws.
     (d) Apply 8000 psi (551.5806 bar) to 8500 psi (586.0543 bar) hydraulic pressure to the tool to move the union ring forward to complete the assembly.
NOTE: Tool pressure is between 8000 psi (551.5806 bar) and 8500 psi (586.0543 bar) for all union sizes or pressure classes.
NOTE: If you use the hand pump (P/N 10-00420A), you must monitor the pressure gage to get the correct pressure.
If you use the foot-operated (P/N 10-00401A) or the switch-operated (P/N 10-00402) ) air/hydraulic intensifier, the intensifier will stop automatically when you have the correct swage pressure.
     (e) Depressurize the assembly tool and remove it from the union.
   (3) Inspection of the assembled union
     (a) Ring position inspection
       1 Get the correct size inspection gage.
F RYNGLOK installation Tooling
With the applicable inspection gage, do a check for correct position of the ring.
Make sure that you can install the inspection gage on the ring (flush).
     (b) Inspection mark
Make sure that the edge of the union touches or is on the inspection mark:
  • This shows that the correct length of tube is engaged in the union.
NOTE: The installation tolerance is divided between the two ends of the union.
If the maximum length of tube is engaged in one end of the union, the minimum length must be engaged in the other end.
This is because unions can move freely on the tube (no positive tube stop).
If the maximum length of tube is engaged, you cannot see the related inspection mark until after the swage.
5. Close-up
Subtask 20-23-11-860-056-A
A. Put the aircraft back to its initial configuration
   (1) Pressurize the hydraulic reservoirs (Ref. AMM TASK 29-14-00-614-002).
   (2) If necessary, fill the hydraulic reservoirs:
   (3) Pressurize the hydraulic systems for 15 minutes:
   (4) Make sure that there is no leakage in the repaired area.
   (5) Bleed the related hydraulic system:
     (a) For the Green system:
     (b) For the Yellow system:
     (c) For the Blue system:
     (d) For the normal braking system (Ref. AMM TASK 32-42-00-870-001).
     (e) For the alternate braking system:
   (6) If applicable, repair the protection on the repaired tube.
     (a) For aluminum tubes:
       1 Apply Surface Pretreatment-Light Alloys Chemical Conversion Yellow - (Material No.10ABC1) on the bare metal area of the tube with a brush.
       2 Complete the protection with Primer Polyurethane Paint_- Corrosion Inhibiting Structure (Material No.04EAC2) .
     (b) For CRES tubes (if painted):
       1 Rub the bare metal area with SCOTCHBRITE.
       2 Apply Wash Primer_- - Structure (Material No.04CMA2) on the bare metal area of the tube.
       3 Complete the protection with Primer Polyurethane Paint_- Corrosion Inhibiting Structure (Material No.04EAC2) .
   (7) Make sure that the work area is clean and clear of tools and other items.
[Rev.10 from 2021] 2026.04.01 04:47:16 UTC
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