Preliminary Requirements

Safety Requirements

CAUTION

YOU CANNOT USE THIS PROCEDURE TO REPAIR STAGE 1 HPT COOLING DUCT ASSEMBLIES THAT ARE PART OF AN ENGINE CONFIGURATION THAT USES STAGE 1 HPT COOLING AIR PRESSURE TUBE. THIS REPAIR PLUG WELDS THE AIR PRESSURE PASSAGE OPENING, PREVENTING THE AIR PRESSURE TUBE FROM FUNCTIONING. REFER TO SB V2500-ENG-0166 FOR REMOVAL OF THE AIR PRESSURE TUBE.

Procedure

1. SUBTASK 72-44-50-350-083 Remove the Honeycomb Ring

   1. Remove the honeycomb ring from the Stage 1 HPT Duct Assembly.

      1. Repair, VRS3179 TASK 72-44-50-300-003 (REPAIR-003).

2. SUBTASK 72-44-50-350-084 Rout Cracks

   1. Refer to Figure and Figure.

   2. Rout to fully remove the cracks in the Air Pressure Passage Boss, below the flange lip.

3. SUBTASK 72-44-50-230-070 Examine the Repair Area

   1. NOTE

      Crack can be removed before weld. It can be done by a certified welder. It is not necessary to get certification from a fluorescent penetrant inspector.

      Do a fluorescent penetrant inspection of the repair area.

      1. Refer to the SPM TASK 70-23-05-230-501. Use high sensitivity procedure.

4. SUBTASK 72-44-50-110-063 Clean the Repair Area

   1. Clean the area to be welded with a stainless steel wire brush.

   2. Solvent wipe the area to be welded.

      1. Refer to the SPM TASK 70-11-26-300-503.

5. SUBTASK 72-44-50-310-057 Weld Repair

   1. NOTE

      Locally manufacture suitable tooling to minimize weld distortion.

      When you repair cracks, the air passage must be plug welded.

      Refer to Figure.

   2. Weld build up the routed area. Use the Manual Gas Tungsten Arc Weld (GTAW-MA) procedure.

      1. Refer to the SPM TASK 70-31-13-310-501. Use CoMat 03-284 WELDING FILLER WIRE, NiBASE.

   3. Plug weld opening of the air pressure passage. Use the Manual Gas Tungsten Arc Weld (GTAW-MA) procedure.

      1. Refer to the SPM TASK 70-31-13-310-501. Use CoMat 03-284 WELDING FILLER WIRE, NiBASE.

6. SUBTASK 72-44-50-370-059 Heat Treat the Repaired Area

   1. NOTE

      Heat treatment can be done with the honeycomb installation by Repair, VRS3179 TASK 72-44-50-300-003 (REPAIR-003).

      Solution heat treat and precipitation harden the stage 1 HPT cooling duct.

      1. Refer to the SPM TASK 70-37-32-370-501.

      2. Solution heat treat the duct at 1725 to 1775 deg F (941 to 968 deg C) for one hour in a protective atmosphere.

      3. Cool at 40 deg F (4 deg C) for one minute or faster to 1300 to 1350 deg F (704 to 732 deg C).

      4. Precipitation heat treat the duct at 1300 to 1350 deg F (704 to 732 deg C) for eight hours.

      5. Furnace cool at a rate of 100 deg F (38 deg C) maximum for one hour to 1125 to 1175 deg F (607 to 635 deg C).

      6. Hold at 1125 to 1175 deg F (607 to 635 deg C) for eight hours.

      7. Air cool to room temperature.

7. SUBTASK 72-44-50-230-071 Examine the Part

   1. Do a fluorescent penetrant inspection of the duct.

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

8. SUBTASK 72-44-50-350-085 Blend the Repaired Area

   1. Refer to Figure.

   2. NOTE

      It is not necessary to blend the inner diameter of the air pressure passage since the rear opening of the passage will be plug welded.

      Blend the repaired area. A mismatch of +0.010 in. (+0.25 mm) is permitted.

      1. Refer to the SPM TASK 70-35-03-300-501.

9. SUBTASK 72-44-50-110-064 Clean the Repaired Area

   1. Clean the duct.

      1. Refer to the SPM TASK 70-11-26-300-503.

10. SUBTASK 72-44-50-220-125 Examine the Part

    1. Refer to Figure.

    2. Examine the duct for hardness. Surface M must be Rockwell 34 HRC minimum or equivalent.

    3. Do a dimensional inspection of the part.

       1. Refer to TASK 72-44-50-200-000 (INSPECTION-000).

11. SUBTASK 72-44-50-350-086 Identify the Repair

    1. Refer to Figure.

    2. Make a mark "VRS3808" adjacent to the part number.

       1. Make a permanent mark by the procedure given in the SPM TASK 70-09-00-400-501.

12. SUBTASK 72-44-50-350-087 Install the Honeycomb Ring

    1. Install the honeycomb ring to the Stage 1 HPT Duct Assembly.

       1. Repair, VRS3179 TASK 72-44-50-300-003 (REPAIR-003).

Figure: Repair Details and Dimensions

Sheet 1



Legend

Repair Details and Dimensions

Sheet 1

Close

Figure: Repair Details and Dimensions

Sheet 2



Legend

Repair Details and Dimensions

Sheet 2

Close

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