Preliminary Requirements

Procedure

1. SUBTASK 72-44-30-350-059 Remove the Detail Parts from the Combustion Chamber Inner Liner

   1. Remove the liner segments and the gangnut channels.

      1. Refer to VRS3173 TASK 72-44-30-300-001 (REPAIR-001) and VRS3264 V2500-A0-72-44-3001-00A-920A-C (REPAIR-003).

2. SUBTASK 72-44-30-110-053 Clean the Damaged Combustion Chamber Inner Liner

   1. Refer to Figure.

   2. Mask the coated surfaces.

      1. Use CoMat 02-182 METAL FOIL TAPE.

   3. Moderately clean or vapor blast the liner to remove debris and fragments.

      1. Refer to the SPM TASK 70-11-03-300-503, SPM TASK 70-11-01-300-503 or SPM TASK 70-12-01-120-501.

3. SUBTASK 72-44-30-230-051 Examine the Damaged Combustion Chamber Inner Liner

   1. Fluorescent penetrant inspect the liner.

      1. Refer to the SPM TASK 70-23-03-230-501 or SPM TASK 70-23-08-230-501 and SPM TASK 70-23-05-230-501.

         1. Make sure you examine all surfaces in addition to the damaged areas.

   2. Remove the damage by machine.

   3. Fluorescent penetrant inspect again. Machine as necessary until the liner is acceptable by fluorescent penetrant inspection.

      1. All corners of the machined area must have a minimum radius of 0.062 in. (1.575 mm).

   4. Examine for the locations and dimensions of the areas where you removed material.

      1. If the areas are only in the shell and each area is less than 0.070 sq in. (45 sq mm), do the procedure in Step.

      2. If the areas are only in the shell and one or more areas are more than 0.070 sq in. (45 sq mm), do the procedure in Step.

4. SUBTASK 72-44-30-370-053 Optional - Solution Heat Treat of the Combustion Chamber Liner

   1. NOTE

      A pre-weld heat treat enhances weldability.

      Solution heat treat of the combustion chamber liner at operator discretion.

      1. Refer to the SPM TASK 70-37-24-370-501.

5. SUBTASK 72-44-30-310-051 Weld Repair the Shell

   1. Refer to Figure.

   2. Weld repair the prepared areas.

      1. Refer to the SPM TASK 70-31-13-310-501, IAE 16-3.

      2. Use the applicable CoMat welding filler wire listed in Figure.

      3. The total area of all weld repairs must not be more than 1.0 sq in. (645 sq mm).

      4. The contour of the welded areas must be in 0.020 in. (0.508 mm) on both sides of perfect form.

   3. Finish the weld on the inside in 0.010 in. (0.254 mm) above or 0.005 in. (0.127 mm) below the base material. Finish the weld on the outside in 0.010 in. (0.254 mm) above the base metal.

      1. Refer to Figure.

   4. Locally stress-relieve the liner after weld repair.

      1. Refer to Step.

   5. Cold work the shell to restore the form if necessary.

   6. Stress-relieve all of the liner again if you cold worked the liner.

      1. Make sure that all details are removed.

      2. It is recommended that the front seal and the rear seal be held in a fixture to prevent distortion.

      3. Refer to Step.

   7. Resize the front inside diameter seal if necessary.

      1. Refer to VRS3306, TASK 72-44-30-300-009 (REPAIR-009).

6. SUBTASK 72-44-30-310-052 Patch Weld the Shell

   1. Refer to Figure and Figure.

   2. NOTE

      Use precaution to keep distortion to a minimum.

      Cut a patch for the area to be repaired.

   3. Use the applicable CoMat stock listed in Figure or cut from a scrap shell of the same material.

      1. The contour of the patch must be in 0.020 in. (0.51 mm) on both sides of perfect form.

      2. Refer to Figure.

   4. Make sure there is a gap of 0.015 in. (0.38 mm) maximum at the edge when you put the patch into the repair area.

   5. Tack the patch in place and weld.

   6. Refer to the SPM TASK 70-31-13-310-501, IAE 16-3.

      1. Use the applicable CoMat welding filler wire listed in Figure.

   7. Finish the weld on the inside in 0.010 in. (0.25 mm) above or 0.005 in. (0.13 mm) below the base material. Finish the weld on the outside in 0.010 in. (0.25 mm) above the base material.

      1. Refer to Figure.

   8. Locally stress-relieve the liner after weld repair.

      1. Refer to Step.

   9. Cold work the shell to restore the form if necessary.

   10. Stress-relieve all of the liner again if you cold worked the liner.

   11. Make sure that all details are removed.

       1. It is recommended that the front seal and the rear seal be held in a fixture to prevent distortion.

       2. Refer to Step.

   12. Resize the front inside diameter seal if necessary.

       1. Refer to VRS3306, TASK 72-44-30-300-009 (REPAIR-009).

7. SUBTASK 72-44-30-370-051 Stress-Relieve the Combustion Chamber Inner Liner

   1. NOTE

      Stress-relief at temperatures higher than 1200 deg F (648.9 deg C) of finish machined steel, nickel and cobalt alloy parts must be done in a suitable protective atmosphere or must be followed by a suitable acid cleaning or descaling. Cooling rates must be selected to minimize distortion.

      Put the part in a cool, 500 deg F (260 deg C) maximum furnace.

      1. Refer to the SPM TASK 70-37-04-370-501 for the atmosphere.

   2. Heat to 600 deg F (315.6 deg C) and hold it for 30 minutes.

   3. Heat to 900 deg F (482.2 deg C) and hold it for 30 minutes.

   4. Heat to 1200 deg F (648.9 deg C) and hold it for 30 minutes.

   5. Heat to 1500 deg F (815.6 deg C) and hold it for 30 minutes.

   6. Heat to 1775 - 1825 deg F (968 - 996 deg C) and hold it for one hour.

   7. Slowly decrease the temperature at a rate of 100 deg F (55.5 deg C) each 15 minutes to a maximum of 500 deg F (260 deg C).

      NOTE

      Air cooling or faster is permitted if dimensional requirements are met.

   8. It is permitted to stress relieve the inner liner. This stress relief may be done instead of the stress relief requirements in steps 9.A. to 9.G.

      1. Use the SPM TASK 70-37-24-370-501.

8. SUBTASK 72-44-30-350-076-001 Install Cooling and Segment Attachment Holes (Manual Method)

   1. Use existing holes as a reference to locate the holes.

      1. Use CoMat 06-072 DYE to mark the locations of the hole rows and the angular locations.

   2. Use usual machining techniques to install the holes.

9. SUBTASK 72-44-30-350-076-002 Install Cooling and Segment Attachment Holes (Automatic Method)

   1. Install the weld repaired assembly onto an NC laser drill, bore mill or Omnimill.

   2. Put the part in a fixture to make sure it is centered and flat.

      1. Use and existing row of holes to establish a machining datum for NC or machine operator reference.

   3. Install the holes and racetracks.

      1. Use an existing row of holes for reference.

10. SUBTASK 72-44-30-220-082 Examine the Combustion Chamber Inner Liner After Repair

    1. Examine the areas that you welded.

       1. Refer to the SPM TASK 70-21-01-220-501.

    2. Examine the dimensions of the inner liner.

       1. Refer to TASK 72-44-30-200-000 (INSPECTION000).

11. SUBTASK 72-44-30-230-053 Fluorescent Penetrant Inspect the Combustion Chamber Inner Liner

    1. Fluorescent penetrant inspect the areas that you welded.

       1. Refer to the SPM TASK 70-23-03-230-501.

12. SUBTASK 72-44-30-220-083 Examine the Hardcoat on the Front Inside Diameter Seal and the Rear Mounting Flange of the Combustion Chamber Inner Liner

    1. Inspect the hardcoat of the front inside diameter seal.

       1. Refer to TASK 72-44-30-200-000 (INSPECTION-000).

    2. Inspect the hardcoat of the rear mounting flange.

       1. Refer to TASK 72-44-30-200-000 (INSPECTION-000).

13. SUBTASK 72-44-30-350-060 Install the Detail Parts to the Combustion Chamber Inner Liner

    1. NOTE

       If you patch repaired the shell, inspect for distortion between the segments after you install the segments. Refer to TASK 72-44-30-200-000.

       Install the liner segments and the gangnut channels.

       1. Refer to VRS3173 TASK 72-44-30-300-001 (REPAIR-001) and VRS3264 V2500-A0-72-44-3001-00A-920A-C (REPAIR-003).

Figure: Repair Details and Dimensions

Repair Details and Dimensions



Figure: Repair Details and Dimensions

Repair Details and Dimensions



Figure: Repair Details and Dimensions

Repair Details and Dimensions



Figure: Repar Details and Dimensions

Repar Details and Dimensions