Preliminary Requirements

Safety Requirements

CAUTION

DO NOT REPAIR ANY BLADE RETAINING PLATE THAT HAS A CRACK OR OTHER UNUSUAL CONDITION FOUND BY FLUORESCENT PENETRANT OR BY A VISUAL EXAMINATION. THESE PARTS MUST BE REJECTED.

Procedure

1. SUBTASK 72-45-33-350-051 Blend Repair Stage 2 Blade Retaining Plate

   1. Refer to Figure.

      NOTE

      Repair of specified area must be made to limits shown in Figure. Unless otherwise specified, closed areas are to corners or points 0.050 in. (1.27 mm) away from tangency points of radii as shown in Figure index 2.

   2. No damage permitted in Area 5 and no blending permitted in Areas 5, 6, 9 and 10. Areas 9 and 10 are restricted to within 0.100 in. (2.540 mm) from the slot edge on the rear face as shown in Figure.

   3. Locally blend all damage and corrosion in area 1 to a maximum depth of 0.008 in. (0.203 mm). The following requirements must be met.

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

         1. Remove 0.002 in. - 0.003 in. (0.051 mm - 0.076 mm) beyond damage depth.

         2. Minimum blend length to depth ratio is 15 to 1.

         3. Blend must be smooth and continuous.

         4. Remove the minimum amount of parent material necessary to remove the damage.

      2. Refer to Step for shotpeen requirements.

   4. Blend to a depth of 0.005 in. (0.127 mm) maximum to remove scattered damage and corrosion on diameter 8. The following requirements must be met.

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

         1. Remove 0.002 in. - 0.003 in. (0.051 mm - 0.076 mm ) beyond damage depth.

         2. Minimum blend length to depth ratio is 15 to 1.

         3. Blend must be smooth and continuous.

         4. Remove the minimum amount of parent material necessary to remove the damage.

         5. Blend length must not be more than 0.500 in. (12.700 mm) maximum in circumferential direction.

         6. A minimum distance of 2.000 in. (50.800 mm) must be kept between blended areas.

      2. Refer to Step for shotpeen requirements.

   5. Locally blend all damage and corrosion in areas 3 and 4 to a maximum depth of 0.010 in (0.254 mm). The following requirements must be met.

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

         1. Remove 0.002 in. - 0.003 in. (0.051 mm - 0.076 mm ) beyond damage depth.

         2. Minimum blend length to depth ratio is 30 to 1 for area 3 and minimum blend length to depth ratio is 15 to 1 for area 4.

         3. Blend must be smooth and continuous.

         4. Remove the minimum amount of parent material necessary to remove the damage.

      2. Refer to Step for shotpeen requirements.

   6. Locally blend all damage and corrosion in area 7 to a maximum depth of 0.005 in (0.127 mm). The following requirements must be met. Area 7 is restricted to within 0.100 in. (25.400 mm) from the slot as shown in Figure.

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

         1. Remove 0.002 in. - 0.003 in. (0.051 mm - 0.076 mm ) beyond damage depth.

         2. Minimum blend length to depth ratio is 30 to 1.

         3. Blend must be smooth and continuous.

         4. Remove the minimum amount of parent material necessary to remove the damage.

         5. After blending in area 7, mark blended slot with an "X" in area indicated in Figure. Do not use slot with "X" marking as the retaining slot during assembly. Marking must be accomplished with only deep electrolytic etch, vibration peen, or deep dot peen. Do not mark over previously blended areas.

      2. Refer to Step for shotpeen requirements.

   7. Remove raised material and sharp edges only when the maximum damage depth at:

      1. Area 6 and Area 10 is 0.001 in. (0.026 mm).

      2. Area 7 and Area 9 is 0.002 in. (0.051 mm).

      3. If raised material or sharp edge is removed at Area 6, Area 7 or Area 10 then mark the repaired slot with "X" by the procedure given in the SPM TASK 70-09-00-400-501. Marking must be accomplished with only deep electrolytic etch, vibration peen or deep dot peen. Refer to Figure for marking area.

2. SUBTASK 72-45-33-230-062 Do a Fluorescent Penetrant Inspection of the Blend Repair Area(s)

   1. Fluorescent Penetrant Inspect of the Blend Repair Area(s) by one of the methods that follow.

      1. FPI repair area(s) by SPM TASK 70-23-04-230-501. Cracks are not permitted.

      2. FPI repair area(s) by SPM TASK 70-23-05-230-501, use ultra-high sensitivity level. Cracks are not permitted.

3. SUBTASK 72-45-33-380-051 Shotpeen the Blend Repair Area(s)

   1. Refer to Figure.

   2. Shotpeen repaired area given in the figure. In area 3 a minimum intensity of 4A must be maintained. In area 2 full coverage is necessary but minimum intensity of 4A is not necessary. No shotpeen allowed in area 1.

      1. Do the procedure given in the SPM TASK 70-38-13-380-501.

      2. Use S-170, CW-20 or SCW-20 shot size with a hardness of 45 to 55 HRC or equivalent.

4. SUBTASK 72-45-33-220-086 Inspect the Stage 2 HPT Blade Retaining Plate

   1. Refer to Figure.

   2. NOTE

      This repair is not to extend the certified life of the blade retaining plate. The function of this repair is to repair blade retaining plates that have been damaged and have not reached their limited life.

      If repairs do not remove the damage of specified areas of the retaining plate.

      1. Reject.

5. SUBTASK 72-45-33-350-052 Identify the Repair

   1. Refer to Figure.

   2. Mark VRS3255 adjacent to the part number.

      1. Make a permanent mark by the procedure given in the SPM TASK 70-09-00-400-501. Marking must be accomplished with only deep electrolytic etch, vibration peen, or deep dot peen.

Figure: HPT Stage 2 Blade retaining Plate Repair Areas

HPT Stage 2 Blade retaining Plate Repair Areas



Figure: HPT Stage 2 Blade Retaining Plate Areas of Peening

HPT Stage 2 Blade Retaining Plate Areas of Peening