* * * FOR ALL
TASK 72-00-00-800-804
1 . General
A.This procedure gives instructions to prepare the borescope inspection of the engine.
B.The borescope procedure can be used to inspect the gas path of the primary airstream.
C.These are the sections of the engine that can be inspected with the borescope procedure:
•
Fan booster assembly (booster) (20-010 , 72-00-02) (SIN 80000)
•
Fan booster assembly (booster) (20-011 , 72-00-02) (SIN 80000) (SB 72-0156)
•
High Pressure Compressor module assembly (HPC):
•
(33-009 , 72-00-02) (SIN 00108)
•
(33-010 , 72-00-02) (SIN 00108)
•
(33-011 , 72-00-02) (SIN 00108) (SB 72-0051)
•
(33-012 , 72-00-02) (SIN 00108) (SB 72-0154)
•
Combustor nozzle diffuser assembly (combustor) (0010A)
•
High pressure turbine stage 2 nozzle assembly (HPT):
•
(34-010 , 72-00-02) (17400)
•
(34-011 , 72-00-02) (17400) (SB 72-0036)
•
(34-012 , 72-00-02) (17400) (SB 72-0154)
•
Low pressure turbine module assembly (LPT) (45-020 , 72-00-02) (SIN 00105)
•
Low pressure turbine module assembly (LPT) (45-021 , 72-00-02) (SIN 00105) (SB 72-0160)
•
Low pressure turbine module assembly (LPT) (45-022 , 72-00-02) (SIN 00105) (SB 72-0160).
D.There are 19 engine borescope ports that give access for the borescope inspection. Refer to Figure 206.
E.The borescope ports have threaded plugs that must be removed to do the borescope inspection. Refer to Table 201 and Figure 209.
NOTE:
The borescope port for the booster inspection does not have a plug.
F.The borescope inspection procedures give the maximum serviceable limits. The engine must be repaired if there is damage or wear that exceeds the maximum serviceable limit.
2 . Tools, Equipment, and Materials.
NOTE:
You can use equivalent alternatives for tools, equipment, and consumable materials.
A.Tools and Equipment.
(1)Special Tools.
 
Tool No.
Description
 
11C3407P01
Turnover Kit - Borescope Inspection (adapter)
 
11C3414P01
Blending Tool, Borescope - Stage 1-9, HPC Blade (borescope blending kit)
 
2129M73G01
Nylon Pry (puller)
 
9481M92P02
Electronic Turnover Tool (turnover kit)
(2)Standard Tools and Equipment.
 
Description
Manufacturer
 
Borescope Kit
Local Purchase
(3)Locally Manufactured Tools. None.
B.Consumable Materials.
 
Code No.
Description
 
C02-019
Oil, Engine Lubricating (engine oil)
 
C02-023
Oil, Engine Lubricating (engine oil)
 
C02-058
Compound, Thread Lubricating (lubricant)
 
C02-061
Deleted
 
C02-071
Anti-Seize and Lubricating Compound (lubricant)
 
C02-097
Tiolube Lubricant, Anti-Seize Compound (primary) (lubricant)
C.Referenced Procedures.
 
ATA No.
Description
 
70-42-00
Blending and Removal of High Metal Procedures
D.Expendable Parts. None.
E.SPD Information. None.
F.Special Solutions. None.
G.Test Specimens. None.
3 . Dimensional Information.
None.
4 . Setup Information.
Subtask 72-00-00-450-001
A.Assemble the borescope inspection tools.
NOTE:
Use the assembly instructions supplied by the borescope tool manufacturer.
NOTE:
It is permitted to substitute the tools specified in the borescope inspection procedures, if the tools used meet the specifications shown in the General Electric Standard Practices Manual (SPM).
NOTE:
The specific configuration of the borescope tool that is necessary to do each inspection is found in the tables in this procedure.
CAUTION:
MAKE SURE THAT THE TEMPERATURE OF THE ENGINE AND THE ADJACENT AREAS, NEAR THE BORESCOPE INSPECTION PORTS, IS LESS THAN 150°F (65.6°C). DO NOT DO A BORESCOPE INSPECTION IF THE ADJACENT AREAS ARE TOO HOT TO TOUCH. DO THE BORESCOPE INSPECTION WHEN THE ENGINE TEMPERATURE IS LESS THAN 150°F (65.6°C). THIS WILL PREVENT DAMAGE TO THE BORESCOPE EQUIPMENT.
(1)Make sure that the internal and external temperature of the engine is less than 150°F (66°C) before you insert the borescope probe into the engine.
(2)If the engine was recently run, measure the temperature of the engine with a metal probe type thermometer.
NOTE:
It is recommended to wait 3 to 5 hours after engine shutdown to do the borescope inspection. This will allow the engine to become sufficiently cool.
NOTE:
You can dry motor the engine to decrease the engine core temperature.
Subtask 72-00-00-220-031
B.The components of the engine that can be inspected at each borescope port location are listed in Table 1. Refer to Figure 204.
Subtask 72-00-00-220-032
C.Radial and axial locations for each borescope port are listed in the Table 2. Refer to Figure 205.
Subtask 72-00-00-220-033
D.Torque values and thread specifications for the borescope plugs are listed in the Table 3. Refer to Figure 207.
NOTE:
The borescope port for the booster inspection does not have a plug.
Subtask 72-00-00-220-034
E.Borescope probe configuration requirements for each borescope port are listed in the Table 4. Refer to Figure 208.
Subtask 72-00-00-040-022
F.To motor the engine core:
(1)Remove the crank cover (01-260 , 72-64-00) (SIN 038AF) from the spur idler crank gearshaft (spur gearshaft) (01-330 , 72-64-00) (SIN 038B5). Refer to Figure 201, Figure 202, and do as follows:
(a)Loosen and remove the four self-locking nuts (01-250 , 72-64-00) (SIN 038W0) that attach the crank cover to the hydraulic pump housing (01-160 , 72-64-00) (SIN 038A9).
(b)Remove the crank cover from the housing. If necessary, use the 2129M73   puller.
(c)Remove and discard the preformed packing (01-270 , 72-64-00) that is installed on the crank cover.
Subtask 72-00-00-490-021
(2)Install the 9481M92   turnover kit and 11C3407   adapter or a 1/2-inch square-drive tool.
Subtask 72-00-00-220-353
G.Prepare for inspection of the booster, HPC, HPT, and LPT as follows:
(1)Do the zero-index alignment as follows:
(a)Use a borescope to view the applicable rotor blade platforms.
(b)With the 9481M92   turnover kit or a 1/2-inch square-drive tool, turn the core motoring counterclockwise (CCW) to turn the rotor.
(c)Look through the borescope, until you see the first locking lug.
(d)Continue to turn the rotor with the core motoring until you see the second locking lug.
(e)Align the leading edge of the blade that follows the second locking lug with the previous stage stator vane.
(f)If the 1/2-inch square-drive tool is used to identify the zero-index point, do as follows:
1Count the number of blades to know when a full turn of the rotor is complete.
(g)If the 9481M92   turnover kit is used to identify the zero-index point, do as follows:
1Use the manufacturer supplied instructions to set the motoring tool display to zero degrees.
(2)Do the required borescope inspection.
Subtask 72-00-00-090-008
H.Remove the motoring tool when the borescope inspection is done and install the crank cover (01-260 , 72-64-00) (SIN 038AF) as follows:
(1)Remove the 9481M92   turnover kit and 11C3407   adapter or a 1/2-inch square-drive tool.
Subtask 72-00-00-490-022
(2)Install the crank cover (01-260 , 72-64-00) (SIN 038AF) on the spur gearshaft (01-330 , 72-64-00) (SIN 038B5). Refer to Figure 201, Figure 202, and do as follows:
WARNING:
REFER TO THE PRODUCT LABEL AND THE MANUFACTURER’S (MATERIAL) SAFETY DATA SHEET FOR INSTRUCTIONS ON THE HAZARDS, STORAGE, SAFE HANDLING AND PROPER USE OF THIS PRODUCT.
(a)Apply C02-019  engine oil or C02-023  engine oil to the preformed packing (01-270 , 72-64-00) (SIN 038NC).
(b)Install the new preformed packing (01-270 , 72-64-00) (SIN 038NC) on the crank cover.
(c)Install the crank cover on the hydraulic pump housing (01-160 , 72-64-00) (SIN 038A9).
WARNING:
REFER TO THE PRODUCT LABEL AND THE MANUFACTURER’S (MATERIAL) SAFETY DATA SHEET FOR INSTRUCTIONS ON THE HAZARDS, STORAGE, SAFE HANDLING AND PROPER USE OF THIS PRODUCT.
(d)Apply C02-019  engine oil or C02-023  engine oil to the four self-locking nuts (01-250 , 72-64-00) (SIN 038W0).
(e)Install the four self-locking nuts (01-250 , 72-64-00) (SIN 038W0) that attach the crank cover to the accessory gearbox (AGB) housing.
(f)Torque the four self-locking nuts (01-250 , 72-64-00) (SIN 038W0) to 57-67 lb in. (6.4-7.6 N.m). Make sure that the minimum locking torque is 3.45 lb in. (0.390 N.m).
Subtask 72-00-00-450-002
I.Install the removed borescope plugs as follows. Refer to Figure 204 and Figure 206.
WARNING:
REFER TO THE PRODUCT LABEL AND THE MANUFACTURER’S (MATERIAL) SAFETY DATA SHEET (SDS) FOR INSTRUCTIONS ON THE HAZARDS, STORAGE, SAFE HANDLING AND PROPER USE OF THIS PRODUCT.
(1)Apply C02-071  lubricant on the borescope plug threads and the mating surfaces.
NOTE:
C02-058  lubricant can be used as an alternative.
(2)Install the borescope plug (01-450 , 72-26-00) (SIN 84090) on the port A as follows:
(a)Do a visual inspection of the borescope plugs and ports. Refer to TASK 72-00-00-800-804 (72-00-00, SPECIAL PROCEDURE 004) (paragraph 5.A. and 5.B.).
(b)Remove the identification tag from borescope plug A.
WARNING:
REFER TO THE PRODUCT LABEL AND THE MANUFACTURER’S (MATERIAL) SAFETY DATA SHEET (SDS) FOR INSTRUCTIONS ON THE HAZARDS, STORAGE, SAFE HANDLING AND PROPER USE OF THIS PRODUCT.
(c)Put C02-071  lubricant on the borescope plug threads and the mating surfaces.
(d)Install the borescope plug in fan hub frame borescope port.
NOTE:
Deleted.
(e)Torque the borescope plug to 110 to 140 lb in. (12.4 to 15.8 Nm).
(f)Deleted.
(3)Install the forward HPC case borescope plug (05-010 , 72-32-00) (SIN 070AK) on the port B, forward HPC case borescope plug (05-020 , 72-32-00) (SIN 070AL) on the port C, forward HPC case borescope plug (05-030 , 72-32-00) (SIN 070AM) on the port D, and forward HPC case borescope plug (05-040 , 72-32-00) (SIN 070AB) on the port E as follows:
Subtask 72-00-00-220-670
* * * PRE SB   72-0246
(a)Do a visual inspection of the borescope plugs and borescope ports. Refer to Subtask 72-00-00-220-035 (paragraph 5.A.) and Subtask 72-00-00-220-042 (paragraph 5.B.).
Subtask 72-00-00-450-015
1Remove the identification tag from borescope plug B through borescope plug E.
Subtask 72-00-00-640-003
WARNING:
REFER TO THE PRODUCT LABEL AND THE MANUFACTURER'S (MATERIAL) SAFETY DATA SHEET (SDS) FOR INSTRUCTIONS ON THE HAZARDS, STORAGE, SAFE HANDLING AND PROPER USE OF THIS PRODUCT.
2Put C02-071  lubricant on the borescope plug threads and the mating surfaces.
NOTE:
You can use C02-058  lubricant as an alternative.
Subtask 72-00-00-450-018
3Install the borescope plugs in the correct forward compressor stator case borescope port. Refer to Figure 201.
NOTE:
When you install the borescope plug, make sure that the slot on the borescope plug is correctly engaged with the lug on the borescope boss before you fully tighten the borescope plug. Refer to Figure 209 for examples of correct and incorrect installations of the self-locking feature of the borescope plug.
4Torque the borescope plugs to 81 to 95 lb in. (9.1 to 10.7 Nm).
Subtask 72-00-00-220-672
5After the borescope plug has been torqued, do a visual inspection of the borescope plug and make sure that the locking feature is fully engaged with the lug on the borescope boss. Also make sure that the head of the borescope plug is fully seated against the borescope boss. If one of the two conditions are not met, the ratcheting feature of the borescope plug can be seized or locked. Apply a penetrating oil directly in between the locking ring and the head of the borescope plug.
Subtask 72-00-00-450-019
6 Re-apply torque to the borescope plug until the borescope plug begins to rotate freely. Tighten the borescope plug from 81 to 95 lb in. (9.1 to 10.7 Nm).
Subtask 72-00-00-220-673
7Do the visual inspection again before proceeding. If the conditions above cannot be met, replace the borescope plug.
* * * END PRE SB   72-0246
Subtask 72-00-00-220-671
* * * SB   72-0246
(a).A.Do a visual inspection of the borescope plugs and borescope ports. Refer to Subtask 72-00-00-220-035 (paragraph 5.A.) and Subtask 72-00-00-220-042 (paragraph 5.B.).
Subtask 72-00-00-450-016
1Remove the identification tag from borescope plug B through borescope plug E.
Subtask 72-00-00-640-004
WARNING:
REFER TO THE PRODUCT LABEL AND THE MANUFACTURER'S (MATERIAL) SAFETY DATA SHEET (SDS) FOR INSTRUCTIONS ON THE HAZARDS, STORAGE, SAFE HANDLING AND PROPER USE OF THIS PRODUCT.
2Put C02-071  lubricant on the borescope plug threads and the mating surfaces.
NOTE:
You can use C02-058  lubricant as an alternative.
Subtask 72-00-00-450-020
3Install the borescope plugs in the correct forward compressor stator case borescope port. Refer to Figure 201.
4Torque the borescope plugs to 81 to 95 lb in. (9.1 to 10.7 Nm).
* * * END SB   72-0246
Subtask 72-00-00-450-017
(4)Install the stage 6 borescope plug (10-010 , 72-30-00) (SIN 080AD) on the port F and stage 7 borescope plug (10-020 , 72-30-00) (SIN 080AU) on the port G as follows:
NOTE:
Digital supplement for installation overview. Refer to GEnx 3D Animation Borescope Plug Installation.
(a)Do a visual inspection of the borescope plugs and ports. Refer to TASK 72-00-00-800-804 (72-00-00, SPECIAL PROCEDURE 004) (paragraph 5.A. and 5.B.).
(b)Remove the identification tag from borescope plug F and G.
WARNING:
REFER TO THE PRODUCT LABEL AND THE MANUFACTURER’S (MATERIAL) SAFETY DATA SHEET (SDS) FOR INSTRUCTIONS ON THE HAZARDS, STORAGE, SAFE HANDLING AND PROPER USE OF THIS PRODUCT.
(c)Put C02-071  lubricant on the borescope plug threads and the mating surfaces.
NOTE:
You can use C02-058  lubricant as an alternative.
(d)Install the borescope plugs in the correct extension case borescope ports as follows:
NOTE:
When you install the borescope plug, make sure that the slot on the plug is correctly engaged with the lug on the borescope boss before you fully tighten the plug. Refer to Figure 209 for examples of correct and incorrect installations of the self-locking feature of the borescope plug.
1Put the borescope plugs in the correct port and hand tighten the inner thread.
NOTE:
While the inner and outer threads are installed, they are pushed up by the spring. Both the inner and outer threads cannot be installed at one time.
2Make sure that the inner threads are correctly mated.
3Torque the inner threads to 81-95 lb in. (9.1-10.7 N.m).
4Loosen and torque the inner threads again to 23-27 lb in. (2.6-3.1 N.m).
5Compress the spring and install the outer threads and hand tighten the borescope plugs.
6Torque the outer threads to 81-95 lb in. (9.1-10.7 N.m).
(e)After the plug has been torqued, perform a visual inspection of the plug and make sure that the locking feature is fully engaged with the lug on the borescope boss. Also make sure that the head of the borescope plug is fully seated against the borescope boss. If one of the two conditions are not met, the ratcheting feature of the plug can be seized or locked. Apply a penetrating oil directly in between the locking ring and the head of the plug. Re-apply torque to the plug until the plug begins to rotate freely. Tighten the plug from 81 to 95 lb in. (9.1 to 10.7 Nm). Do the visual inspection again before proceeding. If the conditions above cannot be met, replace the plug.
Subtask 72-00-00-450-021
* * * PRE SB   72-0436
(5)Install the stage 9 borescope plug (10-040 , 72-30-00) (SIN 080BA) on port I as follows:
NOTE:
Digital supplement for installation overview. Refer to GEnx 3D Animation Borescope Plug Installation.
(a)Do a visual inspection of the borescope plugs and ports. Refer to TASK 72-00-00-800-802 (72-00-00, SPECIAL PROCEDURE 002) (paragraph 5.A. and 5.B.).
(b)Remove the identification tag from borescope plug I.
WARNING:
REFER TO THE PRODUCT LABEL AND THE MANUFACTURER'S (MATERIAL) SAFETY DATA SHEET (SDS) FOR INSTRUCTIONS ON THE HAZARDS, STORAGE, SAFE HANDLING AND PROPER USE OF THIS PRODUCT.
(c)Put C02-071  lubricant on the borescope plug threads and the mating surfaces.
NOTE:
C02-058  lubricant can be used as an alternative.
(d)Install the borescope plugs in the correct extension case borescope ports as follows:
NOTE:
When the borescope plug is installed, make sure that the slot on the plug is correctly engaged with the lug on the borescope boss before you fully tighten the plug. Refer to Figure 209 for examples of correct and incorrect installations of the self-locking feature of the borescope plug.
1Put the borescope plugs in the correct port and hand-tighten the inner thread.
NOTE:
While the inner and outer threads are installed, they are pushed up by the spring. Both the inner and outer threads cannot be installed at one time.
2Make sure that the inner threads are correctly mated.
3Torque the inner threads to 81 to 95 lb in. (9.1 to 10.7 Nm).
4Loosen and torque the inner threads again to 23 to 27 lb in. (2.6 to 3.1 Nm).
5Compress the spring and install the outer threads and hand-tighten the borescope plugs.
6Torque the outer threads to 81 to 95 lb in. (9.1 to 10.7 Nm).
(e)After the plug has been torqued, perform a visual inspection of the plug and make sure that the locking feature is fully engaged with the lug on the borescope boss. Also make sure that the head of the borescope plug is fully seated against the borescope boss. If one of the two conditions are not met, the ratcheting feature of the plug can be seized or locked.
(f)Apply a penetrating oil directly in between the locking ring and the head of the plug.
(g)Re-apply torque to the plug until the plug begins to rotate freely. Torque the plug from 81 to 95 lb in. (9.1 to 10.7 Nm).
(h)Do the visual inspection again before proceeding. If the conditions above cannot be met, replace the plug.
* * * END PRE SB   72-0436
Subtask 72-00-00-450-022
* * * SB   72-0436
(5).A.Install the stage 9 borescope plug (10-040 , 72-30-00) (SIN 080BA) on port I as follows:
NOTE:
Digital supplement for installation overview. Refer to GEnx 3D Animation Borescope Plug Installation.
(a)Do a visual inspection of the borescope plugs and ports. Refer to TASK 72-00-00-800-802 (72-00-00, SPECIAL PROCEDURE 002) (paragraph 5.A. and 5.B.).
(b)Remove the identification tag from borescope plug I.
WARNING:
REFER TO THE PRODUCT LABEL AND THE MANUFACTURER'S (MATERIAL) SAFETY DATA SHEET (SDS) FOR INSTRUCTIONS ON THE HAZARDS, STORAGE, SAFE HANDLING AND PROPER USE OF THIS PRODUCT.
(c)Put C02-071  lubricant on the borescope plug threads and the mating surfaces.
NOTE:
C02-058  lubricant can be used as an alternative.
(d)Install the borescope plugs in the correct extension case borescope ports as follows:
NOTE:
When the borescope plug is installed, make sure that the slot on the plug is correctly engaged with the lug on the borescope boss before you fully tighten the plug. Refer to Figure 209 for examples of correct and incorrect installations of the self-locking feature of the borescope plug.
1Put the borescope plugs in the correct port.
2Make sure that the inner plug is correctly fitted.
3Compress the spring and install the outer threads and hand-tighten the borescope plug.
4Torque the outer threads to 81 to 95 lb in. (9.1 to 10.7 Nm).
(e)After the plug has been torqued, perform a visual inspection of the plug and make sure that the locking feature is fully engaged with the lug on the borescope boss. Also make sure that the head of the borescope plug is fully seated against the borescope boss. If one of the two conditions are not met, the ratcheting feature of the plug can be seized or locked.
(f)Apply a penetrating oil directly in between the locking ring and the head of the plug.
(g)Re-apply torque to the plug until the plug begins to rotate freely. Torque the plug from 81 to 95 lb in. (9.1 to 10.7 Nm).
(h)Do the visual inspection again before proceeding. If the conditions above cannot be met, replace the plug.
* * * END SB   72-0436
Subtask 72-00-00-450-023
(6)Install the stage 8 borescope plug (10-030 , 72-30-00) (SIN 080AW) on the port H as follows:
(a)Do a visual inspection of the borescope plugs and ports. Refer to TASK 72-00-00-800-804 (72-00-00, SPECIAL PROCEDURE 004) (paragraph 5.A. and 5.B.).
(b)Remove the identification tag from borescope plug H.
WARNING:
REFER TO THE PRODUCT LABEL AND THE MANUFACTURER’S (MATERIAL) SAFETY DATA SHEET (SDS) FOR INSTRUCTIONS ON THE HAZARDS, STORAGE, SAFE HANDLING AND PROPER USE OF THIS PRODUCT.
(c)Put C02-071  lubricant on the borescope plug threads and the mating surfaces.
NOTE:
You can use C02-058  lubricant as an alternative.
(d)Install the borescope plug H in the correct extension case borescope port.
NOTE:
When you install the borescope plug, make sure that the slot on the plug is correctly engaged with the lug on the borescope boss before you fully tighten the plug. Refer to Figure 209 for examples of correct and incorrect installations of the self-locking feature of the borescope plug.
(e)Torque the plug to 81-95 lb in. (9.1-10.7 N.m).
(f)After the plug has been torqued, perform a visual inspection of the plug and make sure that the locking feature is fully engaged with the lug on the borescope boss. Also make sure that the head of the borescope plug is fully seated against the borescope boss. If one of the two conditions are not met, the ratcheting feature of the plug can be seized or locked. Apply a penetrating oil directly in between the locking ring and the head of the plug. Re-apply torque to the plug until the plug begins to rotate freely. Tighten the plug from 81 to 95 lb in. (9.1 to 10.7 Nm). Do the visual inspection again before proceeding. If the conditions above cannot be met, replace the plug.
(7)Do a visual inspection of the borescope plugs and mating ports. Refer to TASK 72-00-00-800-804 (72-00-00, SPECIAL PROCEDURE 004) (paragraph 5.A. and 5.B.).
NOTE:
When you install the borescope plug, make sure that the slot on the plug is correctly engaged with the lug on the borescope boss before you fully tighten the plug. Refer to Figure 209 for examples of correct and incorrect installations of the self-locking feature of the borescope plug.
WARNING:
REFER TO THE PRODUCT LABEL AND THE MANUFACTURER’S (MATERIAL) SAFETY DATA SHEET (SDS) FOR INSTRUCTIONS ON THE HAZARDS, STORAGE, SAFE HANDLING AND PROPER USE OF THIS PRODUCT.
(8)Apply C02-071  lubricant to the borescope plug threads and mating surfaces of borescope plugs J, K, L, and M.
NOTE:
You can use C02-058  lubricant as an alternative.
(9)Install the borescope plug J (01-030 , 72-41-00) (SIN 12090), borescope plug K (01-030 , 72-41-00) (SIN 12090), borescope plug L (01-030 , 72-41-00) (SIN 12090), and borescope plug M (01-030 , 72-41-00) (SIN 12090) as follows:
(a)Install the borescope plugs in the combustor case borescope ports. Make sure that the running torque is no more than 15 lb in. (1.7 Nm).
NOTE:
Use of penetrating oil sprayed into locking mechanism is permissible to free/un-bind the locking mechanism. This must be performed before the replacement of the plug.
(b)Torque the borescope plugs to 92 to 108 lb in. (10.4 to 12.2 Nm).
(c)After the plug has been torqued, perform a visual inspection of the plug and make sure that the locking feature is fully engaged with the lug on the borescope boss. Also make sure that the head of the borescope plug is fully seated against the borescope boss. If one of the two conditions are not met, the ratcheting feature of the plug can be seized or locked. Apply a penetrating oil directly in between the locking ring and the head of the plug. Re-apply torque to the plug until the plug begins to rotate freely. Tighten the plug from 92 to 108 lb in. (10.4 to 12.2 Nm). Do the visual inspection again before proceeding. If the conditions above cannot be met, replace the plug.
(10)Do a visual inspection of the borescope plugs and ports. Refer to TASK 72-00-00-800-804 (72-00-00, SPECIAL PROCEDURE 004) (paragraph 5.A. and 5.B.).
NOTE:
When you install the borescope plug, make sure that the slot on the plug is correctly engaged with the lug on the borescope boss before you fully tighten the plug. Refer to Figure 209 for examples of correct and incorrect installations of the self-locking feature of the borescope plug.
WARNING:
REFER TO THE PRODUCT LABEL AND THE MANUFACTURER’S (MATERIAL) SAFETY DATA SHEET (SDS) FOR INSTRUCTIONS ON THE HAZARDS, STORAGE, SAFE HANDLING AND PROPER USE OF THIS PRODUCT.
(11)Apply C02-097  lubricant to the borescope plug threads and mating surfaces of borescope plugs N and O.
NOTE:
You can use C02-071  lubricant or C02-058  lubricant as an alternative.
NOTE:
To reduce the likelihood of plug seizure during removal, it is recommended to use the C02-097  lubricant .
(12)Install borescope plug N (34-250 , 72-00-02) (SIN 17290) and borescope plug O (01-340 , 72-52-00) (SIN 17490) as follows:
(a)Install the borescope plugs in the correct HPT case borescope ports. Make sure that the running torque is no more than 15 lb in. (1.7 Nm).
NOTE:
Use of penetrating oil sprayed into locking mechanism is permissible to free/un-bind the locking mechanism. This must be performed before the replacement of the plug.
(b)Torque the borescope plugs to 142.6 to 167.4 lb in. (16.1 to 18.9 Nm).
(c)After the plug has been torqued, do a visual inspection of the plug and make sure that the locking feature is fully engaged with the lug on the borescope boss. Also make sure that the head of the borescope plug is fully seated against the borescope boss. If one of the two conditions are not met, the ratcheting feature of the plug can be seized or locked. Apply a penetrating oil directly in between the locking ring and the head of the plug. Re-apply torque to the plug until the plug begins to rotate freely. Tighten the plug from 142.6 to 167.4 lb in. (16.1 to 18.9 Nm). Do the visual inspection again before proceeding. If the conditions above cannot be met, replace the plug.
(13)Do a visual inspection of the borescope plugs and ports. Refer to TASK 72-00-00-800-804 (72-00-00, SPECIAL PROCEDURE 004) (paragraph 5.A. and 5.B.).
NOTE:
When you install the borescope plug, make sure that the slot on the plug is correctly engaged with the lug on the borescope boss before you fully tighten the plug. Refer to Figure 209 for examples of correct and incorrect installations of the self-locking feature of the borescope plug.
WARNING:
REFER TO THE PRODUCT LABEL AND THE MANUFACTURER’S (MATERIAL) SAFETY DATA SHEET (SDS) FOR INSTRUCTIONS ON THE HAZARDS, STORAGE, SAFE HANDLING AND PROPER USE OF THIS PRODUCT.
(14)Apply C02-071  lubricant to the borescope plug threads and mating surfaces of borescope plugs P, Q, and R.
(15)Install borescope plug P (01-020 , 72-56-00) (SIN 935S0), borescope plug Q (01-030 , 72-56-00) (SIN 935S1), and borescope plug R (01-040 , 72-56-00) (SIN 935S2) as follows:
(a)Install the borescope plugs in the correct LPT case borescope ports. Make sure that the running torque is no more than 15 lb in. (1.7 Nm).
NOTE:
Use of penetrating oil sprayed into locking mechanism is permissible to free/un-bind the locking mechanism. This must be performed before the replacement of the plug.
(b)Torque the borescope plugs to 150 to 168 lb in. (16.9 to 18.9 Nm).
(c)After the plug has been torqued, perform a visual inspection of the plug and make sure that the locking feature is fully engaged with the lug on the borescope boss. Also make sure that the head of the borescope plug is fully seated against the borescope boss. If one of the two conditions are not met, the ratcheting feature of the plug can be seized or locked. Apply a penetrating oil directly in between the locking ring and the head of the plug. Re-apply torque to the plug until the plug begins to rotate freely. Tighten the plug from 150 to 168 lb in. (16.9 to 18.9 Nm). Do the visual inspection again before proceeding. If the conditions above cannot be met, replace the plug.
(16)Install the blank off plate (30-150 , 72-00-02) (SIN 9500J) as follows:
WARNING:
REFER TO THE PRODUCT LABEL AND THE MANUFACTURER’S (MATERIAL) SAFETY DATA SHEET FOR INSTRUCTIONS ON THE HAZARDS, STORAGE, SAFE HANDLING AND PROPER USE OF THIS PRODUCT.
(a)Apply C02-019  engine oil or C02-023  engine oil on the threads of four machine bolts (bolts) (30-160 , 72-00-02) (SIN 9502C).
(b)Attach the plate (30-150 , 72-00-02) (SIN 9500J) to the cowl support (30-011 , 72-00-02) (SIN 95001) at the 3:30 o’clock position with the four bolts (30-160 , 72-00-02) (SIN 9502C).
(c)Torque the four bolts (30-160 , 72-00-02) (SIN 9502C) to 106-124 lb in. (12.0- 14.0 N.m).
(17)Install the blankoff panel (25-520) (SIN 9500D) to the deflector panels (25-550) (SIN 9500A) at the 3:00 and 4:00 o’clock positions on the cowl support (30-011 , 72-00-02) (SIN 95001) as follows:
WARNING:
REFER TO THE PRODUCT LABEL AND THE MANUFACTURER’S (MATERIAL) SAFETY DATA SHEET (SDS) FOR INSTRUCTIONS ON THE HAZARDS, STORAGE, SAFE HANDLING AND PROPER USE OF THIS PRODUCT.
(a)Apply C02-058   lubricant on the threads of the machine screws (25-510) (SIN 95025).
(b)Install the blankoff panel to the deflector panels at the 3:00 and 4:00 o’clock positions with the machine screws (25-510) (SIN 95025).
(c)Torque the machine screws (25-510) (SIN 95025) to 60-70 lb in. (6.8-7.9 N.n).
* * * FOR ALL
Figure 201   Installation of the Borescope Plugs in Ports F, G, and I
* * * FOR ALL
Figure 202   Manual Motoring of Engine Core
* * * FOR ALL
Figure 203   (Sheet 1 ) Motoring of Engine Core with Turnover Kit, 9481M92
* * * FOR ALL
Figure 203   (Sheet 2 ) Motoring of Engine Core with Turnover Kit, 9481M92
* * * FOR ALL
Figure 204   Borescope Port Locations and Visible Areas
* * * FOR ALL
Figure 205   Radial and Axial Location of Borescope Ports
* * * FOR ALL
Figure 206   (Sheet 1 ) Borescope Port Locations
* * * FOR ALL
Figure 206   (Sheet 2 ) Borescope Port Locations
* * * FOR ALL
Figure 206   (Sheet 3 ) Borescope Port Locations
* * * FOR ALL
Figure 206   (Sheet 4 ) Borescope Port Locations
* * * FOR ALL
Figure 206   (Sheet 5 ) Borescope Port Locations
* * * FOR ALL
Figure 206   (Sheet 6 ) Borescope Port Locations
* * * FOR ALL
Figure 206   (Sheet 7 ) Borescope Port Locations
* * * FOR ALL
Figure 206   (Sheet 8 ) Borescope Port Locations
* * * FOR ALL
Figure 206   (Sheet 9 ) Borescope Port Locations
* * * FOR ALL
Figure 207   Torque Values and Thread Specifications for the Borescope Plugs
* * * FOR ALL
Figure 208   (Sheet 1 ) Borescope Probe Configuration
* * * FOR ALL
Figure 208   (Sheet 2 ) Borescope Probe Configuration
* * * FOR ALL
Figure 208   (Sheet 3 ) Borescope Probe Configuration
5 . Visual Inspection.
Subtask 72-00-00-220-035
A.Do an inspection of the borescope plugs for. Refer to Table 201 and Figure 209.
TABLE 201.Borescope Plugs
 
Borescope Port
Engine Section
CSN and SIN
 
BOOSTER
BOOSTER
N/A
 
A
HPC
(01-450 , 72-26-00) (SIN 84090)
 
B
HPC
(05-010 , 72-32-00) (SIN 070AK)
 
C
HPC
(05-020 , 72-32-00) (SIN 070AL)
 
D
HPC
(05-030 , 72-32-00) (SIN 070AM)
 
E
HPC
(05-040 , 72-32-00) (SIN 070AB)
 
F
HPC
(10-010 , 72-30-00) (SIN 080AD)
 
G
HPC
(10-020 , 72-30-00) (SIN 080AU)
 
H
HPC
(10-030 , 72-30-00) (SIN 080AW)
 
I
HPC
(10-040 , 72-30-00) (SIN 080BA)
 
J
COMBUSTOR
(01-030 , 72-41-00) (SIN 12090)
 
K
COMBUSTOR
(01-030 , 72-41-00) (SIN 12090)
 
L
COMBUSTOR
(01-030 , 72-41-00) (SIN 12090)
 
M
COMBUSTOR
(01-030 , 72-41-00) (SIN 12090)
 
N
HPT
(34-250 , 72-00-02) (SIN 17290)
 
O
HPT
(01-340 , 72-52-00) (SIN 17490)
 
P
LPT
(01-020 , 72-56-00) (SIN 935S0)
 
Q
LPT
(01-030 , 72-56-00) (SIN 935S1)
 
R
LPT
(01-040 , 72-56-00) (SIN 935S2)
(1)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the borescope plug.
Subtask 72-00-00-220-036
(2)Wear on locking device seating face:
Maximum serviceable limit:
0.004 inch (0.10 mm) in depth.
Repair method:
Replace the borescope plug.
Subtask 72-00-00-220-037
(3)Deformation:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the borescope plug.
Subtask 72-00-00-220-038
(4)Broken plug spring:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the borescope plug.
Subtask 72-00-00-220-039
(5)Damaged threads:
Maximum serviceable limit:
The lead-in thread on the borescope plug can be incomplete. Any other thread damage is not serviceable.
Repair method:
Replace the borescope plug.
Subtask 72-00-00-220-040
(6)Anti-rotation feature:
(a)Axially compress the spring by pushing the tabbed locking ring to the plug body with hand force. Keep the spring compressed and turn the plug manually.
Maximum serviceable limit:
•
A plug which does not turn in the removal (counterclockwise) direction is serviceable
•
A plug which turns in the removal (counterclockwise) direction and makes an audible clicking sound is serviceable
•
A plug that turns in the installation (clockwise) direction with or without resistance or an audible clicking sound is serviceable
•
A plug which turns in the removal (counterclockwise) direction with no resistance and no audible clicking sound is not serviceable
•
A plug that does not turn in the installation (clockwise) direction is not serviceable.
Repair method:
Replace the borescope plug.
Subtask 72-00-00-220-041
(7)Damaged or bent locking lugs:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the borescope plug.
Subtask 72-00-00-220-042
B.Do a visual inspection of the ports for:
(1)Loose or missing locking inserts:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the insert.
Subtask 72-00-00-220-043
(2)Damaged threads:
Maximum serviceable limit:
Minor damage to the threads, including burrs or galling, can be repaired.
Maximum repairable limit:
Any amount.
Repair method:
Remove the damage. Use a tap and chase the threads. For thread information, see the Table 3. Refer to Figure 207. If the threads are repaired, make sure that no debris goes into the engine. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) .
* * * FOR ALL
* * * PRE SB   72-0246
Figure 209   (Sheet 1 ) Borescope Plugs
* * * FOR ALL
* * * SB   72-0246
Figure 209   (Sheet 2 ) Borescope Plugs
* * * FOR ALL
* * * PRE SB   72-0246
Figure 209   (Sheet 3 ) Borescope Plugs
* * * FOR ALL
* * * SB   72-0246
Figure 209   (Sheet 4 ) Borescope Plugs
Subtask 72-00-00-220-044
C.Do an inspection of the stage 4 blades (blades).
NOTE:
There are 82 stage 4 blades.
(1)All areas for:
(a)Cracks and tears (high metal):
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the blade.
Subtask 72-00-00-220-354
(b)Erosion or spalling:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-045
(2)Area A for:
(a)Nicks, dents, and scratches in the concave and convex surfaces, not in the leading and trailing edges:
Maximum serviceable limit:
Any amount less than 0.001 inch (0.03 mm) in depth and 0.124 inch (3.15 mm) in length.
Repair method:
Replace the blade.
Subtask 72-00-00-220-046
(b)Nicks, dents, and scratches on the leading and trailing edges:
Maximum serviceable limit:
Any amount, less than 0.015 inch (0.38 mm) in depth. No missing or torn material permitted.
Repair method:
Replace the blade.
Subtask 72-00-00-220-047
(c)Distortion on the leading or trailing edges:
Maximum serviceable limit:
Any amount, if the difference between the initial and the present leading edge position is not more than 0.010 inch (0.25 mm).
Repair method:
Replace the blade.
Subtask 72-00-00-220-048
(3)Area B for:
(a)Nicks, dents, and scratches:
Maximum serviceable limit:
Any amount, 0.015 inch (0.38 mm) in depth, nicks and dents 0.040 inch (1.02 mm) in length, and scratches 0.05 inch (1.3 mm) in length, after the removal of high metal. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) .
Repair method:
Replace the blade.
Subtask 72-00-00-220-049
(b)Local distortion on the leading and/or trailing edge:
Maximum serviceable limit:
0.020 inch (0.51 mm) from the initial contour, if radial length is not more than 0.050 inch (1.27 mm) and axial length is not more than 0.060 inch (1.52 mm).
Repair method:
Replace the blade.
Subtask 72-00-00-220-055
(4)Area C for:
(a)Nicks, dents, and scratches:
Maximum serviceable limit:
Any amount, 0.004 inch (0.10 mm) in depth.
Repair method:
Replace the blade.
Subtask 72-00-00-220-056
(5)Area D for:
(a)Nicks, dents, and scratches on the leading and trailing edges:
Maximum serviceable limit:
Axial length less than 0.005 inch (0.13 mm).
Repair method:
Replace the blade.
Subtask 72-00-00-220-057
(b)Nicks, dents, and scratches on the concave and convex surfaces:
Maximum serviceable limit:
Less than 0.003 inch (0.08 mm) in depth.
Repair method:
Replace the blade.
Subtask 72-00-00-220-355
(c)Tip curl:
Maximum serviceable limit:
Both corners of blade tip. Tip curl must not extend across more than 0.040 inch (1.02 mm) of the leading or trailing edge of the blade tip.
Repair method:
Replace the blade.
Subtask 72-00-00-220-356
(d)Tip burrs:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the blade.
Subtask 72-00-00-220-357
(e)Local rub marks on blade tip:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-358
(f)Wear on blade tip leading and trailing edges:
Maximum serviceable limit:
Axial length less than 0.040 inch (1.02 mm). Radial length less than 0.040 inch (1.02 mm).
Repair method:
Replace the blade.
Subtask 72-00-00-220-058
(g)Missing metal from leading and trailing edge tip corner:
Maximum serviceable limit:
• Axial length less than 0.040 inch (1.02 mm). Radial length less than 0.040 inch (1.02 mm)
• Less than 20 blades are damaged.
Repair method:
Replace the blade.
Subtask 72-00-00-220-059
(6)Blade platforms for:
(a)Nicks, dents, and scratches:
Maximum serviceable limit:
Any amount 0.002 inch (0.05 mm) in depth, after removal of the high metal. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) .
Maximum repairable limit:
Any amount, not more than 0.006 inch (0.15 mm) in depth, after removal of high metal, on two edges of the inner rear platform where the platform touches the booster spool. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) .
Repair method:
Blend. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) .
Subtask 72-00-00-220-060
(b)Interplatform gap:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-061
D.Do an inspection of the stage 5 blades (blades).
NOTE:
There are 84 stage 5 blades.
(1)All areas for:
(a)Cracks and tears (high metal):
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the blade.
Subtask 72-00-00-220-062
(b)Erosion or spalling:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-063
(2)Area A for:
(a)Nicks, dents, and scratches in the concave and convex surfaces, not in the leading and trailing edges:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the blade.
Subtask 72-00-00-220-064
(b)Nicks, dents, and scratches on the leading edges:
Maximum serviceable limit:
Any amount, less than 0.008 inch (0.20 mm) in depth. No missing or torn material permitted.
Repair method:
Replace the blade.
Subtask 72-00-00-220-689
(c)Nicks, dents, and scratches on the trailing edges:
Maximum serviceable limit:
Any amount, less than 0.015 inch (0.38 mm) in depth. No missing or torn material permitted.
Repair method:
Replace the blade.
Subtask 72-00-00-220-065
(d)Distortion on the leading or trailing edges:
Maximum serviceable limit:
Any amount, if difference between the initial and the present leading edge position is no more than 0.010 inch (0.25 mm).
Repair method:
Replace the blade.
Subtask 72-00-00-220-066
(3)Area B for:
(a)Nicks, dents, and scratches:
Maximum serviceable limit:
Any amount, 0.010 inch (0.25 mm) in depth, nicks and dents 0.040 inch (1.02 mm) in length, and scratches 0.05 inch (1.3 mm) in length, after the removal of high metal. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) .
Repair method:
Replace the blade.
Subtask 72-00-00-220-067
(b)Local distortion on the leading and/or trailing edge:
Maximum serviceable limit:
0.020 inch (0.51 mm) from the initial contour, if radial length not more than 0.050 inch (1.27 mm) and axial length not more than 0.060 inch (1.52 mm).
Repair method:
Replace the blade.
Subtask 72-00-00-220-073
(4)Area C for:
(a)Nicks, dents, and scratches:
Maximum serviceable limit:
Any amount, 0.004 inch (0.10 mm) in depth.
Repair method:
Replace the blade.
Subtask 72-00-00-220-074
(5)Area D for:
(a)Nicks, dents, and scratches on the leading and trailing edges:
Maximum serviceable limit:
Axial length less than 0.005 inch (0.13 mm).
Repair method:
Replace the blade.
Subtask 72-00-00-220-075
(b)Nicks, dents, and scratches on the concave and convex surfaces:
Maximum serviceable limit:
Less than 0.003 inch (0.08 mm) in depth.
Repair method:
Replace the blade.
Subtask 72-00-00-220-359
(c)Tip curl:
Maximum serviceable limit:
Both corners of blade tip. Tip curl must not extend across more than 0.040 inch (1.02 mm) of the leading or trailing edge of the blade tip.
Repair method:
Replace the blade.
Subtask 72-00-00-220-360
(d)Tip burrs:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the blade.
Subtask 72-00-00-220-361
(e)Local rub marks on blade tip:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-362
(f)Wear on blade tip leading and trailing edges:
Maximum serviceable limit:
Axial length less than 0.040 inch (1.02 mm). Radial length less than 0.040 inch (1.02 mm).
Repair method:
Replace the blade.
Subtask 72-00-00-220-076
(g)Missing metal from leading and trailing edge tip corner:
Maximum serviceable limit:
• Axial length less than 0.040 inch (1.02 mm). Radial length less than 0.040 inch (1.02 mm)
• Less than 20 blades are damaged.
Repair method:
Replace the blade.
Subtask 72-00-00-220-077
(6)Blade platforms for:
(a)Nicks, dents, and scratches:
Maximum serviceable limit:
Any amount 0.002 inch (0.05 mm) in depth, after removal of the high metal. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) .
Maximum repairable limit:
Any amount, not more than 0.006 inch (0.15 mm) in depth, after removal of high metal, on two edges of the inner rear platform where the platform touches the booster spool. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) .
Repair method:
Blend. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) .
Subtask 72-00-00-220-078
(b)Interplatform gap:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
* * * FOR ALL
Figure 210   Booster Blade
Subtask 72-00-00-220-079
E.Do an inspection of the stage 1 blisk (blisk) (056A1) airfoils. Refer to Figure 211.
(1)All areas for:
(a)Cracks and tears:
Maximum serviceable limit:
Not serviceable.
Maximum repairable limit:
Refer to Table A on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-080
(b)Scratches:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth.
Maximum repairable limit:
Refer to Table A on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-081
(2)Nicks and dents in the center of the airfoil:
Maximum serviceable limit:
Any amount, 0.020 inch (0.51 mm) in depth and 0.080 inch (2.03 mm) in diameter, if the nick or dent are more than 0.090 inch (2.29 mm) from the leading edge, the trailing edge, and the tip.
Repair method:
Replace the blisk.
Subtask 72-00-00-220-082
(3)Nicks, dents, distortion, or material that is missing on the leading and trailing edges of the airfoil:
Maximum serviceable limit:
• In the lower 85 percent of area L, without airfoil root radius: any amount, 0.015 inch (0.38 mm) in depth
• In the upper 15 percent of area L: any amount, 0.020 inch (0.50 mm) in depth.
Maximum repairable limit:
Refer to Table A on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-083
(4)Nicks and dents in the airfoil root radius:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth.
Repair method:
Replace the blisk.
Subtask 72-00-00-220-084
(5)Missing airfoil tip corners:
Maximum serviceable limit:
Any amount, if the downstream damages are serviceable.
Repair method:
Replace the blisk.
NOTE:
Some airfoil tip corners can be chamfered at both leading and trailing edges. This condition is fully serviceable and is not the same as missing corners.
Subtask 72-00-00-220-085
(6)Curled blade tips:
Maximum serviceable limit:
Any amount, 0.350 inch (8.89 mm) in length along the airfoil tip chord, if there are no tears or cracks as a result of the curled blade tip. If a curled blade tip is more than 0.350 inch (8.89 mm) in length, or there are tears or cracks as a result of the curled blade tip, do these steps:
• Replace the engine in 20 cycles or less
• Do an inspection of the opposite engine for stage 1 blade curled blade tips in 5 flight cycles or less.
Repair method:
Replace the blisk.
Subtask 72-00-00-220-086
(7)Distortion or bulging of the leading edge:
Maximum serviceable limit:
Any amount, if the distortion is within these conditions:
• The distortion or bulge is in the top 50 percent of the blade
• Not more than 30 percent of the blade chord is affected
• The length D damage must be more than three times the depth T damage
• There are no tears, cracks, or creases caused by the distortion or bulge
• There are no more than eight blades with distortion or bulges with these conditions:
1) There is no more than one area of distortion or bulging in each blade.
2) There are not more than five blades with a depth T damage of more than 0.050 inch (1.27 mm).
3) Each blade with depth T damage more than 0.050 inch (1.27 mm) is separated by at least two blades with depth T damage less than 0.050 inch (1.27 mm).
Repair method:
Replace the blisk.
Subtask 72-00-00-220-641
(8)Particles on the blade or tip surfaces:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blisk.
Subtask 72-00-00-220-087
F.Do an inspection of the stage 2 blisk (blisk) (056A2) airfoils. Refer to Figure 211.
(1)All areas for:
(a)Cracks and tears:
Maximum serviceable limit:
Not serviceable.
Maximum repairable limit:
Refer to Table A on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-088
(b)Scratches:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth.
Maximum repairable limit:
Refer to Table A on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-089
(2)Nicks and dents in the center of the airfoil:
Maximum serviceable limit:
Any amount, 0.020 inch (0.51 mm) in depth and 0.080 inch (2.03 mm) in diameter, if the nick or dent are more than 0.080 inch (2.03 mm) from the leading edge, the trailing edge, and the tip.
Repair method:
Replace the blisk.
Subtask 72-00-00-220-090
(3)Nicks, dents, distortion, or material that is missing on the leading and trailing edges of the airfoil:
Maximum serviceable limit:
• In the lower 25 percent of area L, excluding airfoil root radius: any amount, 0.010 inch (0.25 mm) in depth
• In the upper 75 percent of area L: any amount, 0.010 inch (0.25 mm) in depth.
Maximum repairable limit:
Refer to Table A on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-091
(4)Nicks and dents in the airfoil root radius:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth.
Repair method:
Replace the blisk.
Subtask 72-00-00-220-092
(5)Missing airfoil tip corners:
Maximum serviceable limit:
Any amount, if the downstream damages are serviceable.
Repair method:
Replace the blisk.
NOTE:
Some airfoil tip corners can be chamfered at both leading and trailing edges. This condition is fully serviceable and is not the same as missing corners.
Subtask 72-00-00-220-093
(6)Curled blade tips:
Maximum serviceable limit:
Any amount, 0.350 inch (8.89 mm) in length along the airfoil tip chord, if there are no tears or cracks as a result of the curled blade tip. If a curled blade tip is more than 0.350 inch (8.89 mm) in length, or there are tears or cracks as a result of the curled blade tip, do these steps:
• Replace the engine in 10 cycles or less
• Do an inspection of the opposite engine for stage 1 blade curled blade tips in 5 flight cycles or less
• If the opposite engine has a curled blade tip of more than 0.350 inch (8.89 mm) in length, or there are tears or cracks as a result of the curled blade tip, replace that engine.
Repair method:
Replace the blisk.
Subtask 72-00-00-220-094
(7)Distortion or bulging of the leading edge:
Maximum serviceable limit:
Any amount, if the distortion is within these conditions:
• The distortion or bulge is in the top 50 percent of the blade
• Not more than 30 percent of the blade chord is affected
• The length D damage must be more than three times the depth T damage
• There are no tears, cracks, or creases caused by the distortion or bulge
• There are no more than eight blades with distortion or bulges, with these conditions:
1) There is no more than one area of distortion or bulging in each blade.
2) There are no more than five blades with a depth T damage of more than 0.050 inch (1.27 mm).
3) Each blade with depth T damage more than 0.050 inch (1.27 mm) is separated by at least two blades with depth T damage less than 0.050 inch (1.27 mm).
Repair method:
Replace the blisk.
Subtask 72-00-00-220-095
(8)Particles on the blade or tip surfaces:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blisk.
Subtask 72-00-00-220-096
G.Do an inspection of the stage 3 compressor rotor blades (057A3).
NOTE:
During borescope inspection, gaps between blade platforms can be visible. Gaps are normal and there is no limit to gap size.
(1)All areas for:
(a)Cracks and tears:
Maximum serviceable limit:
Not serviceable.
Maximum repairable limit:
Refer to Table B on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-097
(b)Radial tip cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the blade.
Subtask 72-00-00-220-098
(c)Scratches:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth.
Maximum repairable limit:
Refer to Table B on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-099
(2)Nicks and dents in the center of the airfoil:
Maximum serviceable limit:
Any amount, 0.080 inch (2.03 mm) in diameter, if the nick or dent are more than 0.080 inch (2.03 mm) from the leading edge, the trailing edge, and the tip, and if all nicks and dents are separated from other nicks and dents by at least 0.330 inch (8.38 mm). A nick or dent that pushes metal through to the opposite side is permitted.
Repair method:
Replace the blade.
Subtask 72-00-00-220-100
(3)Nicks, dents, distortion, or material that is missing on the leading and trailing edges of the airfoil, except the tip corner:
Maximum serviceable limit:
• In the lower 80 percent of area L, excluding airfoil root radius: any amount, 0.020 inch (0.51 mm) in depth
• In the upper 20 percent of area L: any amount, 0.010 inch (0.25 mm) in depth.
Maximum repairable limit:
Refer to Table B on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-101
(4)Nicks and dents in the airfoil root radius (except leading edge of root radius):
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth.
Repair method:
Replace the blade.
Subtask 72-00-00-220-755
(5)Nicks and dents on the leading edge of the airfoil root radius:
Maximum serviceable limit:
Any amount, 0.005 inch (0.12 mm) in depth.
Repair method:
Replace the blade.
Subtask 72-00-00-220-102
(6)Missing airfoil tip corners:
Maximum serviceable limit:
Any amount, if the downstream damages are serviceable.
Repair method:
Replace the blade.
NOTE:
Some airfoil tip corners can be chamfered at both leading and trailing edges. This condition is fully serviceable and is not the same as missing corners.
Subtask 72-00-00-220-103
(7)Curled blade tips:
Maximum serviceable limit:
Any amount, 0.350 inch (8.89 mm) in length along the airfoil tip chord, if there are no tears or cracks as a result of the curled blade tip.
Repair method:
Replace the blade.
Subtask 72-00-00-220-104
(8)Cracks, tears, nicks, dents, distortion, and material that is missing from the tip corner:
Maximum serviceable limit:
Any amount, if cracks, tears, nicks, dents, distortion, or material that is missing do not extend axially or radially out of the leading edge tip corner area.
Repair method:
Blend. Any amount of blending to remove damage in the leading edge tip corner region is permitted. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-105
(9)Particles on the blade or tip surfaces:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-106
(10)Erosion of the tip, airfoil, and tip corner:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-107
(11)Burrs and high metal on the blade tips due to blade rub:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-743
(12)Nicks, dents, pits, and scratches on the top surface of the platform:
Maximum serviceable limit:
Any amount, 0.005 inch (0.12 mm) in depth, any length.
Repair method:
Replace the blade.
Subtask 72-00-00-220-744
(13)Nicks, dents, pits, rubs, and scratches on the edges of the platform:
Maximum serviceable limit:
Any amount, 0.005 inch (0.12 mm) in depth, any length.
Repair method:
Replace the blade.
Subtask 72-00-00-220-108
H.Do an inspection of the stage 4 compressor rotor blades (blades) (057A4).
NOTE:
During borescope inspection, gaps between blade platforms can be visible. Gaps are normal and there is no limit to gap size.
NOTE:
The deflectors can move and block the borescope hole. If this condition is found, it is permitted to move the deflector to clear the borescope hole.
NOTE:
Wear on the HPC rear deflectors and/or case interfaces due to HPC rear deflector vibration and movement is a usual condition and must be addressed by introducing new configuration deflectors when the HPC forward stator case is exposed.
(1)All areas for:
(a)Cracks and tears:
Maximum serviceable limit:
Not serviceable.
Maximum repairable limit:
Refer to Table B on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-109
(b)Radial tip cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the blade.
Subtask 72-00-00-220-110
(c)Scratches:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth.
Maximum repairable limit:
Refer to Table B on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-111
(2)Nicks and dents in the center of the airfoil:
Maximum serviceable limit:
Any amount, 0.080 inch (2.03 mm) in diameter, if the nick or dent are more than 0.080 inch (2.03 mm) from the leading edge, the trailing edge, and the tip, and if all nicks and dents are separated from other nicks and dents by at least 0.330 inch (8.38 mm). A nick or dent that pushes metal through to the opposite side is permitted.
Repair method:
Replace the blade.
Subtask 72-00-00-220-112
(3)Nicks, dents, distortion, or material that is missing on the leading and trailing edges of the airfoil, except the tip corner:
Maximum serviceable limit:
• In the lower 50 percent of area L excluding airfoil root radius: any amount, 0.025 inch (0.64 mm) in depth
• In the upper 50 percent of area L: any amount, 0.017 inch (0.43 mm) in depth.
Maximum repairable limit:
Refer to Table B on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-113
(4)Nicks and dents in the airfoil root radius:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth.
Repair method:
Replace the blade.
Subtask 72-00-00-220-114
(5)Missing airfoil tip corners:
Maximum serviceable limit:
Any amount, if the downstream damages are serviceable.
Repair method:
Replace the blade.
NOTE:
Some airfoil tip corners can be chamfered at both leading and trailing edges. This condition is fully serviceable and is not the same as missing corners.
Subtask 72-00-00-220-115
(6)Curled blade tips:
Maximum serviceable limit:
Any amount, 0.350 inch (8.89 mm) in length along the airfoil tip chord, if there are no tears or cracks as a result of the curled blade tip.
Repair method:
Replace the blade.
Subtask 72-00-00-220-116
(7)Cracks, tears, nicks, dents, distortion, and material that is missing from the tip corner:
Maximum serviceable limit:
Any amount, if cracks, tears, nicks, dents, distortion, or material that is missing do not extend axially or radially out of the leading edge tip corner area.
Repair method:
Blend. Any amount of blending to remove damage in the leading edge tip corner region is permitted. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-117
(8)Particles on the blade or tip surfaces:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-118
(9)Erosion of the tip, airfoil, and tip corner:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-119
(10)Burrs and high metal on the blade tips due to blade rub:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-745
(11)Nicks, dents, pits, and scratches on the top surface of the platform:
Maximum serviceable limit:
Any amount, 0.005 inch (0.12 mm) in depth, any length.
Repair method:
Replace the blade.
Subtask 72-00-00-220-746
(12)Nicks, dents, pits, rubs, and scratches on the edges of the platform:
Maximum serviceable limit:
Any amount, 0.005 inch (0.12 mm) in depth, any length.
Repair method:
Replace the blade.
Subtask 72-00-00-220-120
I.Do an inspection of the stage 5 blisk (blisk) (056A5) airfoils.
(1)All areas for:
(a)Cracks and tears:
Maximum serviceable limit:
Not serviceable.
Maximum repairable limit:
Refer to Table A on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-121
(b)Scratches:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth.
Maximum repairable limit:
Refer to Table A on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-122
(2)Nicks and dents in the center of the airfoil:
Maximum serviceable limit:
Any amount, 0.020 inch (0.51 mm) in depth and 0.080 inch (2.03 mm) in diameter, if the nick or dent are more than 0.080 inch (2.03 mm) from the leading edge, the trailing edge, and the tip, and if the nick or dent do not make a hole in the blade.
Repair method:
Replace the blisk.
Subtask 72-00-00-220-123
(3)Nicks, dents, distortion, or material that is missing on the leading and trailing edges of the airfoil, except the tip corner:
Maximum serviceable limit:
• In the lower 25 percent of area L, excluding airfoil root radius: any amount, 0.030 inch (0.76 mm) in depth
• In the upper 75 percent of area L: any amount, 0.030 inch (0.76 mm) in depth.
Maximum repairable limit:
Refer to Table A on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-124
(4)Nicks and dents in the airfoil root radius:
NOTE:
In case of indication above the limit on the airfoil root fillet, contact to GE for potential mitigation.
Maximum serviceable limit:
Any amount, 0.005 inch (0.13 mm) in depth.
Repair method:
Replace the blisk.
Subtask 72-00-00-220-125
(5)Missing airfoil tip corners:
Maximum serviceable limit:
Any amount, if the downstream damages are serviceable.
Repair method:
Replace the blisk.
NOTE:
Some airfoil tip corners can be chamfered at both leading and trailing edges. This condition is fully serviceable and is not the same as missing corners.
Subtask 72-00-00-220-126
(6)Curled blade tips:
Maximum serviceable limit:
Any amount, 25 percent of the airfoil tip chord length, if there are no tears or cracks as a result of the curled blade tip.
Repair method:
Replace the blisk.
Subtask 72-00-00-220-127
(7)Distortion or bulging of the leading edge:
Maximum serviceable limit:
Any amount, if the distortion is within these conditions:
• The distortion or bulge is in the top 50 percent of the blade
• Not more than 30 percent of the blade chord is affected
• The length D damage must be more than three times the depth T damage
• There are no tears, cracks, or creases caused by the distortion or bulge
• There are no more than eight blades with distortion or bulges, with these conditions:
1) There is no more than one area of distortion or bulging in each blade.
2) There are not more than five blades with a depth T damage of more than 0.050 inch (1.27 mm).
3) Each blade with depth T damage of more than 0.050 inch (1.27 mm) is separated by at least two blades with depth T damage of less than 0.050 inch (1.27 mm).
Repair method:
Replace the blisk.
Subtask 72-00-00-220-368
(8)Airfoil tip heat discoloration:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blisk.
Subtask 72-00-00-220-642
(9)Particles on the blade or tip surfaces:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blisk.
Subtask 72-00-00-220-128
J.Do an inspection of the stage 6 blades (blades) (057A6, 057AD, 057AE, 057AF). Refer to Figure 211.
NOTE:
During borescope inspection, gaps between blade platforms can be visible. Gaps are normal and there is no limit to gap size.
(1)All areas for:
(a)Cracks and tears:
Maximum serviceable limit:
Not serviceable.
Maximum repairable limit:
Refer to Table B on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-129
(b)Radial tip cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the blade.
Subtask 72-00-00-220-130
(c)Scratches:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth.
Maximum repairable limit:
Refer to Table B on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-131
(2)Nicks and dents in the center of the airfoil:
Maximum serviceable limit:
Any amount, 0.080 inch (2.03 mm) in diameter, if the nick or dent are more than 0.080 inch (2.03 mm) from the leading edge, the trailing edge, and the tip, and if the nick or dent do not make a hole in the blade, and if all nicks and dents are separated from other nicks and dents by at least 0.330 inch (8.38 mm). A nick or dent that pushes metal through to the opposite side is permitted.
Repair method:
Replace the blade.
Subtask 72-00-00-220-132
(3)Nicks, dents, distortion, or material that is missing on the leading and trailing edges of the airfoil, except the tip corner:
Maximum serviceable limit:
• In the lower 25 percent of area L, excluding airfoil root radius: any amount, 0.030 inch (0.76 mm) in depth
• In the upper 75 percent of area L: any amount, 0.030 inch (0.76 mm) in depth.
Maximum repairable limit:
Refer to Table B on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-133
(4)Nicks in the airfoil root radius:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth.
Repair method:
Replace the blade.
Subtask 72-00-00-220-643
* * * FOR ALL.ALL
(5)Dents in the airfoil root radius except leading edge of the root radius:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth.
Repair method:
Replace the blade.
Subtask 72-00-00-220-644
* * * FOR ALL.ALL
(6)Dents in leading edge of the root radius:
Maximum serviceable limit:
• Any amount, 0.003 inch (0.07 mm) in depth
• One dent permitted up to 0.005 inch (0.13 mm) in depth, with a length to depth ratio of 7 to 1. This criteria is not applicable when there is more than one dent in the leading edge root radius.
Repair method:
Replace the blade.
Subtask 72-00-00-220-134
(7)Missing airfoil tip corners:
Maximum serviceable limit:
Any amount, if the downstream damages are serviceable.
Repair method:
Replace the blade.
NOTE:
Some airfoil tip corners can be chamfered at both leading and trailing edges. This condition is fully serviceable and is not the same as missing corners.
Subtask 72-00-00-220-135
(8)Curled blade tips:
Maximum serviceable limit:
Any amount, 25 percent of the airfoil tip chord length, if there are no tears or cracks as a result of the curled blade tip.
Repair method:
Replace the blade.
Subtask 72-00-00-220-136
(9)Cracks, tears, nicks, dents, distortion, and material that is missing from the tip corner:
Maximum serviceable limit:
Any amount, if cracks, tears, nicks, dents, distortion, or material that is missing do not extend axially or radially out of the leading edge tip corner area.
Repair method:
Blend. Any amount of blending to remove damage in the leading edge tip corner region is permitted. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-137
(10)Particles on the blade or tip surfaces:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-138
(11)Erosion of the tip, airfoil, and tip corner:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-139
(12)Burrs and high metal on the blade tips due to blade rub:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-747
(13)Nicks, dents, pits, and scratches on the top surface of the platform:
Maximum serviceable limit:
Any amount, 0.005 inch (0.12 mm) in depth, any length.
Repair method:
Replace the blade.
Subtask 72-00-00-220-748
(14)Nicks, dents, pits, rubs, and scratches on the edges of the platform:
Maximum serviceable limit:
Any amount, 0.005 inch (0.12 mm) in depth, any length.
Repair method:
Replace the blade.
Subtask 72-00-00-220-140
K.Do an inspection of the stage 7 blades (blade) (057A7, 057AG, 057AH, 057AJ). Refer to Figure 211.
NOTE:
During borescope inspection, gaps between blade platforms can be visible. Gaps are normal and there is no limit to gap size.
(1)All areas for:
(a)Cracks and tears:
Maximum serviceable limit:
Not serviceable.
Maximum repairable limit:
Refer to Table B on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-141
(b)Radial tip cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the blade.
Subtask 72-00-00-220-142
(c)Scratches:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth.
Maximum repairable limit:
Refer to Table B on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-143
(2)Nicks and dents in the center of the airfoil:
Maximum serviceable limit:
Any amount, 0.080 inch (2.03 mm) in diameter, if the nick or dent are more than 0.080 inch (2.03 mm) from the leading edge, the trailing edge, and the tip, and if the nick or dent do not make a hole in the blade, and if all nicks and dents are separated from other nicks and dents by at least 0.330 inch (8.38 mm). A nick or dent that pushes metal through to the opposite side is permitted.
Repair method:
Replace the blade.
Subtask 72-00-00-220-144
(3)Nicks, dents, distortion, or material that is missing on the leading and trailing edges of the airfoil, except the tip corner:
Maximum serviceable limit:
• In the lower 25 percent of area L, excluding airfoil root radius: any amount, 0.025 inch (0.64 mm) in depth
• In the upper 75 percent of area L: any amount, 0.025 inch (0.64 mm) in depth.
Maximum repairable limit:
Refer to Table B on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-145
(4)Nicks in the airfoil root radius:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth.
Repair method:
Replace the blade.
Subtask 72-00-00-220-645
* * * FOR ALL.ALL
(5)Dents in the airfoil root radius except leading edge of the root radius:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth.
Repair method:
Replace the blade.
Subtask 72-00-00-220-646
* * * FOR ALL.ALL
(6)Dents in leading edge of the root radius:
Maximum serviceable limit:
• Any amount, 0.003 inch (0.07 mm) in depth
• One dent permitted up to 0.005 inch (0.13 mm) in depth, with a length to depth ratio of 7 to 1. This criteria is not applicable when there is more than one dent in the leading edge root radius.
Repair method:
Replace the blade.
Subtask 72-00-00-220-146
(7)Missing airfoil tip corners:
Maximum serviceable limit:
Any amount, if the downstream damages are serviceable.
Repair method:
Replace the blade.
NOTE:
Some airfoil tip corners can be chamfered at both leading and trailing edges. This condition is fully serviceable and is not the same as missing corners.
Subtask 72-00-00-220-147
(8)Curled blade tips:
Maximum serviceable limit:
Any amount, 25 percent of the airfoil tip chord length, if there are no tears or cracks as a result of the curled blade tip.
Repair method:
Replace the blade.
Subtask 72-00-00-220-148
(9)Cracks, tears, nicks, dents, distortion, and material that is missing from the tip corner:
Maximum serviceable limit:
Any amount, if cracks, tears, nicks, dents, distortion, or material that is missing do not extend axially or radially out of the leading edge tip corner area.
Repair method:
Blend. Any amount of blending to remove damage in the leading edge tip corner region is permitted. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-149
(10)Particles on the blade or tip surfaces:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-150
(11)Erosion of the tip, airfoil, and tip corner:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-151
(12)Burrs and high metal on the blade tips due to blade rub:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-749
(13)Nicks, dents, pits, and scratches on the top surface of the platform:
Maximum serviceable limit:
Any amount, 0.005 inch (0.12 mm) in depth, any length.
Repair method:
Replace the blade.
Subtask 72-00-00-220-750
(14)Nicks, dents, pits, rubs, and scratches on the edges of the platform:
Maximum serviceable limit:
Any amount, 0.005 inch (0.12 mm) in depth, any length.
Repair method:
Replace the blade.
Subtask 72-00-00-220-152
L.Do an inspection of the stage 8 regular blades (blades) (057A8, 057B8, 057C8, 057D8).
NOTE:
During borescope inspection, gaps between blade platforms can be visible. Gaps are normal and there is no limit to gap size.
(1)All areas for:
(a)Cracks and tears:
Maximum serviceable limit:
Not serviceable.
Maximum repairable limit:
Refer to Table B on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-153
(b)Radial tip cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the blade.
Subtask 72-00-00-220-154
(c)Scratches:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth.
Maximum repairable limit:
Refer to Table B on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-155
(2)Nicks and dents in the center of the airfoil:
Maximum serviceable limit:
Any amount, 0.080 inch (2.03 mm) in diameter, if the nick or dent are more than 0.080 inch (2.03 mm) from the leading edge, the trailing edge, and the tip, and if the nick or dent do not make a hole in the blade, and if all nicks and dents are separated from other nicks and dents by at least 0.330 inch (8.38 mm). A nick or dent that pushes metal through to the opposite side is permitted.
Repair method:
Replace the blade.
Subtask 72-00-00-220-156
(3)Nicks, dents, distortion, or material that is missing on the leading and trailing edges of the airfoil, except the tip corner:
Maximum serviceable limit:
• In the upper 40 percent span of area L: any amount, 0.025 inch (0.63 mm) in depth
• In the lower 60 percent span of area L, excluding the airfoil root radius: any amount, 0.040 inch (1.01 mm) in depth.
Maximum repairable limit:
Refer to Table B on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-157
(4)Nicks in the airfoil root radius:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth.
Repair method:
Replace the blade.
Subtask 72-00-00-220-647
* * * FOR ALL.ALL
(5)Dents in the airfoil root radius except leading edge of the root radius:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth.
Repair method:
Replace the blade.
Subtask 72-00-00-220-648
* * * PRE SB   72-0157
(6)Dents in leading edge of the root radius:
Maximum serviceable limit:
•
Any amount, 0.003 inch (0.07 mm) in depth
•
One dent permitted up to 0.005 inch (0.13 mm) in depth, with a length to depth minimum ratio of 7 to 1. This criteria is not applicable when there is more than one dent in the leading edge root radius.
Repair method:
Replace the blade.
* * * END PRE SB   72-0157
Subtask 72-00-00-220-714
* * * SB   72-0157
(6).A.Dents in leading edge of the root radius:
Maximum serviceable limit:
•
Any amount, 0.003 inch (0.07 mm) in depth.
•
One dent is permitted in a maximum of 0.016 inch (0.41 mm) in depth, with a length to depth minimum ratio of 2 to 1. This criteria is not applicable when there is more than one dent in the leading edge root radius.
Repair method:
Replace the blade.
* * * END SB   72-0157
Subtask 72-00-00-220-158
(7)Missing airfoil tip corners:
Maximum serviceable limit:
Any amount, if the downstream damages are serviceable.
Repair method:
Replace the blade.
NOTE:
Some airfoil tip corners can be chamfered at both leading and trailing edges. This condition is fully serviceable and is not the same as missing corners.
Subtask 72-00-00-220-159
(8)Curled blade tips:
Maximum serviceable limit:
Any amount, 25 percent of the airfoil tip chord length, if there are no tears or cracks as a result of the curled blade tip.
Repair method:
Replace the blade.
Subtask 72-00-00-220-160
(9)Cracks, tears, nicks, dents, distortion, and material that is missing from the tip corner:
Maximum serviceable limit:
Any amount, if cracks, tears, nicks, dents, distortion, or material that is missing do not extend axially or radially out of the leading edge tip corner area.
Repair method:
Blend. Any amount of blending to remove damage in the leading edge tip corner region is permitted. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-161
(10)Particles on the blade or tip surfaces:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-162
(11)Erosion of the tip, airfoil, and tip corner:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-163
(12)Burrs and high metal on the blade tips due to blade rub:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-751
* * * FOR ALL.ALL
(13)Nicks, dents, pits, and scratches on the top surface of the platform:
Maximum serviceable limit:
Any amount, 0.005 inch (0.12 mm) in depth, any length.
Repair method:
Replace the blade.
Subtask 72-00-00-220-752
* * * FOR ALL.ALL
(14)Nicks, dents, pits, rubs, and scratches on the edges of the platform:
Maximum serviceable limit:
Any amount, 0.005 inch (0.12 mm) in depth, any length.
Repair method:
Replace the blade.
Subtask 72-00-00-220-164
M.Do an inspection of the stage 9 regular blades (blades) (057A9, 057B9, 057C9, 057D9).
NOTE:
During borescope inspection, gaps between blade platforms can be visible. Gaps are normal and there is no limit to gap size.
(1)All areas for:
(a)Cracks and tears:
Maximum serviceable limit:
Not serviceable.
Maximum repairable limit:
Refer to Table B on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-165
(b)Radial tip cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the blade.
Subtask 72-00-00-220-166
(c)Scratches:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth.
Maximum repairable limit:
Refer to Table B on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-167
(2)Nicks and dents in the center of the airfoil:
Maximum serviceable limit:
Any amount, 0.080 inch (2.03 mm) in diameter, if the nick or dent are more than 0.080 inch (2.03 mm) from the leading edge, the trailing edge, and the tip, and if the nick or dent do not make a hole in the blade, and if all nicks and dents are separated from other nicks and dents by at least 0.330 inch (8.38 mm). A nick or dent that pushes metal through to the opposite side is permitted.
Repair method:
Replace the blade.
Subtask 72-00-00-220-168
(3)Nicks, dents, distortion, or material that is missing on the leading and trailing edges of the airfoil, except the tip corner:
Maximum serviceable limit:
• In the 40 percent thru 75 percent span of area L: any amount, 0.025 inch (0.63 mm) in depth
• In the lower 40 percent, excluding the airfoil root radius and upper 25 percent spans of area L: any amount, 0.040 inch (1.01 mm) in depth.
Maximum repairable limit:
Refer to Table B on Figure 224.
Repair method:
Blend. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-169
(4)Nicks in the airfoil root radius:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth.
Repair method:
Replace the blade.
Subtask 72-00-00-220-649
* * * FOR ALL.ALL
(5)Dents in the airfoil root radius except leading edge of the root radius:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth.
Repair method:
Replace the blade.
Subtask 72-00-00-220-650
* * * FOR ALL.ALL
(6)Dents in leading edge of the root radius:
Maximum serviceable limit:
• Any amount, 0.003 inch (0.07 mm) in depth
• One dent permitted up to 0.005 inch (0.13 mm) in depth, with a length to depth ratio of 7 to 1. This criteria is not applicable when there is more than one dent in the leading edge root radius.
Repair method:
Replace the blade.
Subtask 72-00-00-220-170
(7)Missing airfoil tip corners:
Maximum serviceable limit:
Any amount, if the downstream damages are serviceable.
Repair method:
Replace the blade.
NOTE:
Some airfoil tip corners can be chamfered at both leading and trailing edges. This condition is fully serviceable and is not the same as missing corners.
Subtask 72-00-00-220-171
(8)Curled blade tips:
Maximum serviceable limit:
Any amount, 25 percent of the airfoil tip chord length, if there are no tears or cracks as a result of the curled blade tip.
Repair method:
Replace the blade.
Subtask 72-00-00-220-172
(9)Cracks, tears, nicks, dents, distortion, and material that is missing from the tip corner:
Maximum serviceable limit:
Any amount, if cracks, tears, nicks, dents, distortion, or material that is missing do not extend axially or radially out of the leading edge tip corner area.
Repair method:
Blend. Any amount of blending to remove damage in the leading edge tip corner region is permitted. Refer to Subtask 72-00-00-350-002 (paragraph 6.A.) .
Subtask 72-00-00-220-173
(10)Particles on the blade or tip surfaces:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-174
(11)Erosion of the tip, airfoil, and tip corner:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-175
(12)Burrs and high metal on the blade tips due to blade rub:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-753
* * * FOR ALL.ALL
(13)Nicks, dents, pits, and scratches on the top surface of the platform:
Maximum serviceable limit:
Any amount, 0.005 inch (0.12 mm) in depth, any length.
Repair method:
Replace the blade.
Subtask 72-00-00-220-754
* * * FOR ALL.ALL
(14)Nicks, dents, pits, rubs, and scratches on the edges of the platform:
Maximum serviceable limit:
Any amount, 0.005 inch (0.12 mm) in depth, any length.
Repair method:
Replace the blade.
* * * FOR ALL
Figure 211   (Sheet 1 ) HPC Section Inspection
* * * FOR ALL
Figure 211   (Sheet 2 ) HPC Section Inspection
* * * FOR ALL
Figure 211   (Sheet 3 ) HPC Section Inspection
* * * FOR ALL
Figure 211   (Sheet 4 ) HPC Section Inspection
* * * FOR ALL
Figure 211   (Sheet 5 ) HPC Section Inspection
Subtask 72-00-00-220-176
N.Do an inspection of the combustion chamber assembly (01-090 , 72-41-00) (SIN 12400) or (01-091 , 72-41-00) (SIN 12400) or (01-092 , 72-41-00) (SIN 12400) or (01-093 , 72-41-00) (SIN 12400). Refer to Figure 213 and as follows:
(1)All areas for:
(a)Discoloration:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the combustion chamber assembly.
Subtask 72-00-00-220-177
(b)Carbon accumulation:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the combustion chamber assembly.
Subtask 72-00-00-220-178
(2)Deflectors on the combustion chamber dome assembly (dome assembly) for:
(a)Circumferential or radial cracks (this does not include dome plate):
Maximum serviceable limit:
Any amount, not more than 0.250 inch (6.35 mm) in length.
Repair method:
Replace the dome assembly.
Subtask 72-00-00-220-179
(b)Circumferential or radial cracks on dome plate:
Maximum serviceable limit:
Any amount, not more than 0.250 inch (6.35 mm) in length, not connected, 2.0 inches (51 mm) minimum separation. No cracks permitted in the bend radii.
Repair method:
Replace the dome assembly.
Subtask 72-00-00-220-180
(c)Spalling or missing thermal barrier coating (TBC):
Maximum serviceable limit:
Any amount.
Repair method:
Replace the dome assembly.
Subtask 72-00-00-220-181
(d)Missing material, burns, and erosion:
Maximum serviceable limit:
Any amount, if the maximum number of exposed dome plate cooling holes is 20 per deflector.
NOTE: There are a total of 22 deflectors.
Repair method:
Replace the dome assembly.
Subtask 72-00-00-220-182
(3)Combustion chamber inner liner (inner liner) (01-110 , 72-42-00) (SIN 12400 3) or (01-110A , 72-42-00) (SIN 12400 3) or (01-110B , 72-42-00) (SIN 12400 3) or (01-111 , 72-42-00) (SIN 12400 3). Refer to Figure 214.
(a)Cracks:
Maximum serviceable limit:
Any amount, 0.5 inch (12.7 mm) in length.
Repair method:
Replace the inner liner.
Subtask 72-00-00-220-183
(b)Burn through or missing material:
Maximum serviceable limit:
• Any amount, if less than 0.10 inch (2.5 mm) by 0.10 inch (2.5 mm) in area
• Four areas if each between 0.10 inch (2.5 mm) and 0.40 inch (10.2 mm) by 0.10 inch (2.5 mm) and 0.40 inch (10.2 mm) in area.
Repair method:
Replace the inner liner.
Subtask 72-00-00-220-184
(c)Distortion:
Maximum serviceable limit:
Any amount, 0.5 inch (12.7 mm) from initial contour.
Repair method:
Replace the inner liner.
Subtask 72-00-00-220-185
(d)Spalling or erosion of the thermal barrier coating:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the inner liner.
Subtask 72-00-00-220-186
(4)Combustion chamber outer liner (outer liner) for. Refer to Figure 215.
(a)Cracks:
Maximum serviceable limit:
Any amount, 0.5 inch (12.7 mm) in length.
Repair method:
Replace the outer liner.
Subtask 72-00-00-220-187
(b)Burn through or missing material:
Maximum serviceable limit:
• Any amount, if less than 0.10 inch (2.5 mm) by 0.10 inch (2.5 mm) in area
• Four areas if each between 0.10 inch (2.5 mm) and 0.40 inch (10.2 mm) by 0.10 inch (2.5 mm) and 0.40 inch (10.2 mm) in area.
Repair method:
Replace the outer liner.
Subtask 72-00-00-220-188
(c)Distortion:
Maximum serviceable limit:
Any amount, 0.5 inch (12.7 mm) from initial contour.
Repair method:
Replace the outer liner.
Subtask 72-00-00-220-189
(d)Spalling or erosion of the thermal barrier coating:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the outer liner.
Subtask 72-00-00-220-190
(5)Borescope and igniter ports of the outer liner area X for. Refer to Figure 216.
(a)Missing thermal barrier coating:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the outer liner.
Subtask 72-00-00-220-191
(b)Circumferential cracks:
Maximum serviceable limit:
0.5 inch (12.7 mm) in length.
Repair method:
Replace the outer liner.
Subtask 72-00-00-220-192
(c)Axial cracks:
Maximum serviceable limit:
0.5 inch (12.7 mm) in length.
Repair method:
Replace the outer liner.
Subtask 72-00-00-220-193
(d)Connected cracks:
Maximum serviceable limit:
• Cracks that make two legs of a triangle between holes 1.2 inch (30.5 mm) in length
• Cracks that start to be three legs of a triangle are permitted, if you do inspection check at 125 cycle intervals.
Repair method:
Replace the outer liner.
Subtask 72-00-00-220-194
(e)Burn through or missing material:
Maximum serviceable limit:
• One area forward of igniter or borescope port center line less than 0.16 sq in. (1.03 sq cm)
• One area adjacent to igniter or borescope port less than 0.16 sq in. (1.03 sq cm).
Repair method:
Replace the outer liner.
Subtask 72-00-00-220-195
(6)Radial mixer area W for. Refer to Figure 216.
(a)Oxidation or missing metal:
Maximum serviceable limit:
Any amount in area W.
Repair method:
Replace the radial mixer.
Subtask 72-00-00-220-196
(7)Fuel nozzles:
(a)Carbon accumulation:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the fuel nozzle.
Subtask 72-00-00-220-197
(b)Missing thermal barrier coating:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the fuel nozzle.
Subtask 72-00-00-220-198
(c)Oxidation or missing metal:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the fuel nozzle.
Subtask 72-00-00-220-199
O.Do an inspection of the stage 1 nozzles (nozzle segments) (01-020 , 72-51-00) (SIN 172A0) or (01-021 , 72-51-00) (SIN 172A0) or (01-022 , 72-51-00) (SIN 172A0) or (01-023 , 72-51-00) (SIN 172A0) and (01-010 , 72-51-00) (SIN 172A8) or (01-011 , 72-51-00) (SIN 172A8) or (01-012 , 72-51-00) (SIN 172A8) or (01-013 , 72-51-00) (SIN 172A8). Refer to Figure 212.
(1)Leading edges of the vane airfoils for:
(a)Missing thermal barrier coating:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-200
(b)Cracks that connect the nose holes:
Maximum serviceable limit:
Any amount, 0.500 inch (12.70 mm) long, not connected, if there is no missing material.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-201
(c)Cracks that extend from a nose hole(s) but do not connect with another nose hole(s):
Maximum serviceable limit:
Any amount, if there is no missing material.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-202
(d)Burns or erosion (the surface is burned and no holes through the parent metal):
Maximum serviceable limit:
Total less than 0.5 inch (12.7 mm) in diameter for each vane, if there are no more than four burned vanes on a 90 degree arc.
Repair method:
Replace three nozzle segments upstream of the damaged area, if adjacent vanes are locally damaged.
* * * FOR ALL
Figure 212   Nozzle Segments
* * * FOR ALL
Figure 213   Dome Assembly
* * * FOR ALL
Figure 214   Inner Liner
* * * FOR ALL
Figure 215   (Sheet 1 ) Outer Liner
* * * FOR ALL
Figure 215   (Sheet 2 ) Outer Liner
* * * FOR ALL
Figure 216   Combustion Chamber Assembly
Subtask 72-00-00-220-203
P.Do an inspection of the nozzle segments (01-020 , 72-51-00) (SIN 172A0) or (01-021 , 72-51-00) (SIN 172A0) or (01-022 , 72-51-00) (SIN 172A0) or (01-023 , 72-51-00) (SIN 172A0) and (01-010 , 72-51-00) (SIN 172A8) or (01-011 , 72-51-00) (SIN 172A8) or (01-012 , 72-51-00) (SIN 172A8) or (01-013 , 72-51-00) (SIN 172A8). Refer to Figure 212.
(1)Concave side of each vane airfoil on the nozzle:
(a)Radial cracks that connect gill holes of the forward row:
Maximum serviceable limit:
Any amount, if there is no missing material.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-204
(b)Axial cracks:
Maximum serviceable limit:
Any amount, if there is no missing material.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-205
(c)Cracks in the fillet area adjacent to the inner and outer platforms:
Maximum serviceable limit:
Any amount, if there is no missing material.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-206
(d)Other cracks, not in the gill holes:
Maximum serviceable limit:
Any amount, if there is no missing material.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-207
(e)Burns (no holes through the vane airfoil):
Maximum serviceable limit:
Any amount, if there is no missing material.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-208
(2)Convex side of each vane airfoil on the nozzle for:
(a)Radial cracks that connect gill holes of the forward row:
Maximum serviceable limit:
Any amount, if there is no missing material.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-209
(b)Axial cracks:
Maximum serviceable limit:
Any amount, if there is no missing material.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-210
(c)Cracks in the fillet area adjacent to the inner and outer platforms:
Maximum serviceable limit:
Any amount, if there is no missing material.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-211
(d)Other cracks, not in the gill holes:
Maximum serviceable limit:
Any amount, if there is no missing material.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-212
(e)Burns (no holes through the vane airfoil):
Maximum serviceable limit:
Any amount, if there is no missing material.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-213
(3)Trailing edge of each vane airfoil on the nozzle:
(a)Axial cracks in that start at the slots adjacent to the trailing edge:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-214
(b)Bulging or bowing:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-215
(c)Missing material:
Maximum serviceable limit:
Less than 1.5 sq in. (9.68 sq cm) for each airfoil.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-216
(4)All areas of the nozzle segment for:
(a)Craze cracks:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-217
(b)Nicks, scores, scratches, and dents:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-218
(c)Metal splatter:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-219
(5)Inner platform of each nozzle segment:
(a)Cracks in parent metal:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-220
(b)Nicks, scores, scratches, and dents:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-221
(c)Burns (no holes through the platform):
Maximum serviceable limit:
Any amount, if no material is missing and the burns are not fully through.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-222
(d)Bulging or bowing:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-223
(6)Outer platform of each nozzle segment for:
(a)Cracks in parent metal:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-224
(b)Nicks, scores, scratches, and dents:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-225
(c)Burns (no holes through the platform):
Maximum serviceable limit:
Any amount.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-226
(d)Bulging or bowing:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-227
Q.Do an inspection of the HPT stage 1 blades (blades) (150A0). Refer to Figure 217.
(1)Airfoil surfaces of each blade:
(a)Missing surface coating:
Maximum serviceable limit:
Any amount outside of area X, if there are no holes or cracks in the blade. A maximum of 0.250 inch (6.35 mm) in diameter or the equivalent area of 0.049 sq in. (31.613 sq mm) is permitted in area X.
Repair method:
Replace the blade.
Subtask 72-00-00-220-228
(b)Radial cracks on the pressure (concave) airfoil between, but not related to row 9 and 10 air holes:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the blade.
Subtask 72-00-00-220-229
(c)Cracks on concave side of the airfoil that come from row 10 cooling holes 8 through 15:
Maximum serviceable limit:
Any amount, less than 0.250 inch (6.35 mm) in length, if cracks do not connect with cracks from adjacent holes.
Repair method:
Replace the blade.
Subtask 72-00-00-220-363
(d)Cracks on the concave side of the airfoil that go out of row 15 of the cooling holes toward row 12 of the cooling holes:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the blade.
Subtask 72-00-00-220-230
(2)Leading edge for:
(a)Axial and radial cracks in the nose holes (rows 4 thru 8) in area P:
Maximum serviceable limit:
Any amount if:
• Crack does not connect more than three holes
• Crack does not extend farther than the nose holes
• Crack does not extend farther than the convex surface gill holes.
Repair method:
Replace the blade.
Subtask 72-00-00-220-231
(b)Axial cracks in the nose holes (rows 4 thru 8) in area Q:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the blade.
Subtask 72-00-00-220-232
(c)Radial cracks that go out of the area Q leading edge holes:
Maximum serviceable limit:
Any amount if:
• Crack does not connect more than two holes
• Crack does not turn in an axial direction.
Repair method:
Replace the blade.
Subtask 72-00-00-220-233
(d)Nicks and dents in area P:
Maximum serviceable limit:
Any number, if nick, dent, and any related crack do not extend farther than the nose holes or the convex surface gill holes.
Repair method:
Replace the blade.
Subtask 72-00-00-220-234
(e)Nicks and dents in area Q:
Maximum serviceable limit:
Any number, if nick, dent, and any related crack do not extend farther than the nose holes or the convex surface gill holes and there are no tears or missing material.
Repair method:
Replace the blade.
Subtask 72-00-00-220-235
(f)Missing material in areas P and Q:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the blade.
Subtask 72-00-00-220-236
(g)Deleted.
Subtask 72-00-00-220-364
(h)Blocked nose holes (rows 4 thru 8) in area P:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the blade.
Subtask 72-00-00-220-365
(i)Blocked nose holes (rows 4 thru 8) in area Q:
Maximum serviceable limit:
One blocked cooling hole.
Repair method:
Replace the blade.
Subtask 72-00-00-220-237
(3)Concave side of each blade for:
(a)Radial cracks at the film and gill hole:
Maximum serviceable limit:
• Any number, above the second gill hole from the top, if radial cracks connect a maximum of two holes and do not turn in an axial direction
• Not serviceable below the fifth gill hole.
Repair method:
Replace the blade.
Subtask 72-00-00-220-238
(b)Radial cracks in areas P and Q other than at the film or gill holes:
Maximum serviceable limit:
One, no longer than space between four gill holes (0.40 inch (10.16 mm)), does not turn in axial direction, internal cavity of the blade cannot be seen.
Repair method:
Replace the blade.
Subtask 72-00-00-220-239
(c)Deleted.
Subtask 72-00-00-220-240
(d)Radial cracks that go out of the tips of the film holes:
Maximum serviceable limit:
Three, if cracks do not:
• Go into the next film hole
• Go in the direction of the blade platform from the bottom hole
• Go in axial direction.
Repair method:
Replace the blade.
Subtask 72-00-00-220-241
(e)Nicks and dents in area P:
Maximum serviceable limit:
Any amount, if there are no tears, cracks, or holes that go through the surface metal.
Repair method:
Replace the blade.
Subtask 72-00-00-220-242
(f)Nicks and dents in area Q:
Maximum serviceable limit:
• Any amount, if less than space between two gill holes (0.07 inch (1.78 mm)) in diameter
• Not serviceable in root radius.
Repair method:
Replace the blade.
Subtask 72-00-00-220-243
(g)Axial cracks in areas P and Q:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the blade.
Subtask 72-00-00-220-244
(h)Twisted, bent, burnt, or melted airfoil surfaces:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the blade.
Subtask 72-00-00-220-245
(4)Convex side of each blade for:
(a)Radial cracks at the film and gill hole:
Maximum serviceable limit:
• Any number, above the second gill hole from the top, if radial cracks connect a maximum of two holes and do not turn in an axial direction
• Not serviceable below the fifth gill hole.
Repair method:
Replace the blade.
Subtask 72-00-00-220-246
(b)Radial cracks in areas P and Q other than at the film or gill holes:
Maximum serviceable limit:
One, no longer than space between four gill holes (0.40 inch (10.16 mm)), does not turn in axial direction, internal cavity of the blade cannot be seen.
Repair method:
Replace the blade.
Subtask 72-00-00-220-247
(c)Deleted.
Subtask 72-00-00-220-248
(d)Radial cracks that go out of the tips of the film holes:
Maximum serviceable limit:
Three, if cracks do not:
• Go into the next film hole
• Go in the direction of the blade platform from the bottom hole
• Go in axial direction.
Repair method:
Replace the blade.
Subtask 72-00-00-220-249
(e)Nicks and dents in area P:
Maximum serviceable limit:
Any amount, if there are no tears, cracks, or holes that go through the surface metal.
Repair method:
Replace the blade.
Subtask 72-00-00-220-250
(f)Nicks and dents in area Q:
Maximum serviceable limit:
• Any amount, if there are no tears, cracks, or holes that go through the surface metal
• Not serviceable in root radius.
Repair method:
Replace the blade.
Subtask 72-00-00-220-251
(g)Axial cracks in areas P and Q:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the blade.
Subtask 72-00-00-220-252
(h)Twisted, bent, burnt, or melted airfoil surfaces:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the blade.
Subtask 72-00-00-220-253
(5)Trailing edge for:
(a)Axial cracks in area P:
Maximum serviceable limit:
Any amount, less than 0.30 inch (7.62 mm) from the trailing edge.
Repair method:
Replace the blade.
Subtask 72-00-00-220-254
(b)Axial cracks in area Q but not in the root fillet radius:
Maximum serviceable limit:
Any amount, less than 0.30 inch (7.62 mm) in length.
Repair method:
Replace the blade.
Subtask 72-00-00-220-255
(c)Axial cracks in the fillet radius:
Maximum serviceable limit:
Any amount, less than 0.200 inch (5.08 mm) in length, if cracks do not turn in radial direction.
Repair method:
Replace the blade.
Subtask 72-00-00-220-256
(d)Nicks in areas P and Q:
Maximum serviceable limit:
Any amount, if there are no related cracks or missing or torn material.
Repair method:
Replace the blade.
Subtask 72-00-00-220-257
(e)Deleted.
Subtask 72-00-00-220-258
(f)Dents in areas P and Q:
Maximum serviceable limit:
Any amount, not more than the length of one trailing edge slot 0.150 inch (3.81 mm) in length or diameter, not more than 0.040 inch (1.02 mm) in depth, if there is no metal extrusion from the dent into the trailing edge slot.
Repair method:
Replace the blade.
Subtask 72-00-00-220-259
(g)Deleted.
Subtask 72-00-00-220-260
(h)Tears in areas P and Q:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the blade.
Subtask 72-00-00-220-261
(i)Deleted.
Subtask 72-00-00-220-262
(j)Oxidation in the root fillet radius:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the blade.
Subtask 72-00-00-220-263
(k)Missing metal in areas P and Q, but not in the root fillet radius:
Maximum serviceable limit:
Any amount, if internal cavity of the blade cannot be seen.
Repair method:
Replace the blade.
Subtask 72-00-00-220-264
(l)Missing metal in the root fillet radius:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the blade.
Subtask 72-00-00-220-265
(6)Blade tip area for:
NOTE:
The blade tip is defined as the area in 0.350 inch (8.89 mm) of the end of the blade.
(a)Axial cracks:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-266
(b)Bent or curled blade tips:
Maximum serviceable limit:
Two areas that are not more than four gill holes in length, if they do not go below the tip cap.
Repair method:
Replace the blade.
Subtask 72-00-00-220-267
(c)Buildup of first stage shroud material:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the blade.
Subtask 72-00-00-220-268
(d)Radial cracks that start at the concave or convex blade tip:
Maximum serviceable limit:
• Any amount, if less than 0.350 inch (8.89 mm) from the blade tip
• If the inner cavities of the blade cannot be seen
• It is permitted for cracks to intersect the top cooling holes in a concave film row.
Repair method:
Replace the blade.
Subtask 72-00-00-220-269
(e)Missing metal on concave or convex side:
Maximum serviceable limit:
• Missing metal does not go below tip cap
• Inner cavities cannot be seen.
Repair method:
Replace the blade.
Subtask 72-00-00-220-270
(7)Blade platform for:
(a)Cracks on the pressure side of the platform:
Maximum serviceable limit:
One. It is permitted for the crack to extend from the edge of the platform through the platform cooling holes to the airfoil root radius, if it does not extend farther than the first cooling hole on row 15.
Repair method:
Replace the blade.
Subtask 72-00-00-220-271
(b)Cracks on the trailing edge of the platform:
Maximum serviceable limit:
Three, if:
• Not between the platform cooling holes
• Not between the platform cooling holes and airfoil root radius
• There are no lifting material between cracks
• It is permitted for the crack to extend from the platform trailing edge to the platform cooling holes.
Repair method:
Replace the blade.
Subtask 72-00-00-220-272
R.Do an inspection of the HPT stage 2 nozzle assembly (HPT stage 2 nozzle). This inspection is limited to what can be seen with a rigid borescope. Refer to Figure 218.
(1)HPT stage 1 shroud (stage 1 shroud) (17300) flowpath surface for:
(a)Axial cracks:
Maximum serviceable limit:
• Any amount, 0.15 inch (3.81 mm) in length
• Four, 1.00 inch (25.4 mm) in length
• One, completely across the flowpath surface, if separated from other cracks by a minimum of 0.125 inch (3.18 mm)
• Not serviceable, if three or more axial and circumferential cracks connect
• Not serviceable, if cracks are converging and are within 0.125 inch (3.18 mm) of each other.
Repair method:
Replace the stage 1 shroud.
Subtask 72-00-00-220-273
(b)Circumferential cracks:
Maximum serviceable limit:
Any amount, 0.375 inch (9.53 mm) in length, 0.125 inch (3.18 mm) apart.
Repair method:
Replace the stage 1 shroud.
Subtask 72-00-00-220-274
(2)Vane airfoils of each HPT stage 2 nozzle (nozzle segment) (174A0, 174A1) for. This inspection is limited to what can be seen with a rigid borescope.
(a)Missing surface coating:
Maximum serviceable limit:
Any amount, on a single airfoil, if total amount from all the airfoils is less or equal to 45 percent.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-275
(b)Nicks, scores, scratches, and dents:
Maximum serviceable limit:
Any amount, 0.25 inch (6.35 mm) in diameter, 0.03 inch (0.76 mm) in depth.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-276
(3)Leading edge of each vane airfoil on the nozzle segments (174A0, 174A1) for:
(a)Axial cracks:
Maximum serviceable limit:
• One, 0.30 inch (7.62 mm) in length
• Any amount, if there are no separated cracks in the surface coating
• Not serviceable in area E.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-277
(b)Burns:
Maximum serviceable limit:
One area, 1.00 inch (25.4 mm) in length by 0.40 inch (10.16 mm) in width.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-278
(4)Concave surfaces of each vane airfoil on the nozzle segments (174A0, 174A1) for:
(a)Cracks:
Maximum serviceable limit:
Two, 0.70 inch (17.78 mm) in length.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-279
(b)Burns (no holes through the vane airfoil):
Maximum serviceable limit:
One area, 1.00 sq in. (6.45 sq cm.).
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-280
(5)Convex surfaces of each vane airfoil on the nozzle segments (174A0, 174A1) for:
(a)Cracks to the outer platform fillet area:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-281
(b)Cracks:
Maximum serviceable limit:
Two, less than 0.500 inch (12.70 mm) in length and separated from the inner and outer platform by 0.500 inch (12.70 mm).
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-282
(c)Burns (no holes through the vane airfoil):
Maximum serviceable limit:
One area, 1.00 sq in. (6.45 sq cm.).
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-283
(6)Trailing edge of each vane airfoil on the nozzle segments (174A0, 174A1) for:
(a)Axial cracks that are more than 0.40 inch (10.2 mm) from the inner and outer platform:
Maximum serviceable limit:
• Any amount, 0.090 inch (2.29 mm) in length
• Two, for each vane airfoil, 0.500 inch (12.70 mm) in length, if the cracks are 0.25 inch (6.4 mm) apart.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-284
(b)Axial cracks or craze cracks that are less than 0.40 inch (10.2 mm) from the inner platform:
Maximum serviceable limit:
Any amount, if not extend more than 0.500 inch (12.70 mm) from the trailing edge.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-285
(c)Missing material:
Maximum serviceable limit:
One area, 0.250 inch (6.35 mm) in an axial direction by 0.500 inch (12.70 mm) in a radial direction.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-286
(7)Inner platform of each vane airfoil on the nozzle segments (01-370 , 72-52-00) (SIN 174A0) or (01-371 , 72-52-00) (SIN 174A0) or (01-372 , 72-52-00) (SIN 174A0) for:
(a)Cracks:
Maximum serviceable limit:
Any amount, 0.300 inch (7.62 mm) in length.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-287
(b)Craze cracks:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-288
(c)Cracks on the trailing edge of the platform:
Maximum serviceable limit:
Any number, 0.15 inch (3.81 mm) on length in the borescope nozzle segment, if the HPT stage 2 blade forward angel wing rub is 0.010 inch (0.25 mm) or less.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-289
(d)Nicks, scores, scratches, and dents:
Maximum serviceable limit:
Any amount, 0.03 inch (0.76 mm) in depth.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-290
(e)Missing surface coating:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-291
(f)Heat distress (network of fine cracks):
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-292
(g)Burns:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-293
(8)Outer platform of each vane airfoil on the nozzle segments (174A0, 174A1) for:
(a)Cracks:
Maximum serviceable limit:
Any amount, 0.300 inch (7.62 mm) in length.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-294
(b)Craze cracks:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-295
(c)Cracks on the trailing edge of the platform:
Maximum serviceable limit:
Any amount, 0.400 inch (10.16 mm) in length, if the cracks do not go into the fillet radius.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-296
(d)Nicks, scores, scratches, and dents:
Maximum serviceable limit:
Any amount, 0.03 inch (0.76 mm) in depth.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-297
(e)Missing surface coating:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the nozzle segment.
Subtask 72-00-00-220-298
(9)Rub surface of each HPT stator stage 2 shroud (stage 2 shroud) (17800) for:
(a)Pickup caused by blade rub:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the stage 2 shroud.
Subtask 72-00-00-220-299
S.Do an inspection of the stage 2 blade (150B0). Refer to Figure 218.
(1)Airfoil surfaces of each stage 2 blade for:
(a)Missing platinum aluminide coating:
Maximum serviceable limit:
Any amount, if there are no holes or cracks in the blade.
Repair method:
Replace the stage 2 blade.
Subtask 72-00-00-220-366
* * * SB   72-0042( Stage 2 Blade with Thermal Barrier Coating )
* * * PRE SB   72-0080( Stage 2 Blade with Thermal Barrier Coating )
(b)Missing thermal barrier coating:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the stage 2 blade.
NOTE:
PRE SB 72-0042 and SB 72-0080 do not require inspection of the stage 2 blade for missing thermal barrier coating.
* * * END SB   72-0042
* * * END PRE SB   72-0080
Subtask 72-00-00-220-300
(c)Deleted.
Subtask 72-00-00-220-301
(2)Leading edge for:
(a)Cracks in area J:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the stage 2 blade.
Subtask 72-00-00-220-302
(b)Cracks in area K:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the stage 2 blade.
Subtask 72-00-00-220-303
(c)Nicks and dents in areas J and K:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the stage 2 blade.
Subtask 72-00-00-220-304
(d)Missing metal in areas J and K:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the stage 2 blade.
Subtask 72-00-00-220-305
(e)Metal splatter:
Maximum serviceable limit:
Any amount. If metal splatter is seen on the convex side of the blade area C, do an inspection of all stage two nozzle segments for heat distress and burns in the inner platforms. Refer to Subtask 72-00-00-220-291 (paragraph 5.R.(7)(f)) and Subtask 72-00-00-220-292 (paragraph 5.R.(7)(g)) . Inspection of all the nozzle segments requires the use of a flexible borescope.
Repair method:
Replace the stage 2 blade.
Subtask 72-00-00-220-306
(3)Concave side of each blade for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the stage 2 blade.
Subtask 72-00-00-220-307
(b)Nicks and dents:
Maximum serviceable limit:
Any amount, 0.250 inch (6.35 mm) in diameter, no torn metal, minimum 0.500 inch (12.70 mm) from the blade platform.
Repair method:
Replace the stage 2 blade.
Subtask 72-00-00-220-308
(c)Positive braze metal in area D:
Maximum serviceable limit:
0.003 inch (0.08 mm) above the concave surface.
Repair method:
Replace the stage 2 blade.
Subtask 72-00-00-220-309
(4)Convex side of each blade for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the stage 2 blade.
Subtask 72-00-00-220-310
(b)Nicks and dents:
Maximum serviceable limit:
Any amount, 0.25 inch (6.35 mm) in diameter, no torn metal, minimum 0.500 inch (12.70 mm) from the blade platform.
Repair method:
Replace the stage 2 blade.
Subtask 72-00-00-220-311
(c)Positive braze metal in area D:
Maximum serviceable limit:
0.003 inch (0.08 mm) above the convex surface.
Repair method:
Replace the stage 2 blade.
Subtask 72-00-00-220-312
(5)Trailing edge for:
(a)Cracks in area J:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the stage 2 blade.
Subtask 72-00-00-220-313
(b)Cracks in area K:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the stage 2 blade.
Subtask 72-00-00-220-314
(c)Nicks and dents in areas J and K:
Maximum serviceable limit:
Any amount, minimum 0.500 inch (12.70 mm) from the blade platform.
Repair method:
Replace the stage 2 blade.
Subtask 72-00-00-220-315
(d)Missing metal in areas J and K:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the stage 2 blade.
Subtask 72-00-00-220-316
(e)Metal splatter:
Maximum serviceable limit:
Any amount. If metal splatter is seen on the convex side of the blade area C, do an inspection of all stage two nozzle segments for heat distress and burns in the inner platforms. Refer to Subtask 72-00-00-220-291 (paragraph 5.R.(7)(f)) and Subtask 72-00-00-220-292 (paragraph 5.R.(7)(g)) . Inspection of all the nozzle segments requires the use of a flexible borescope.
Repair method:
Replace the stage 2 blade.
Subtask 72-00-00-220-317
(6)Blade tip area for:
(a)Radial cracks:
Maximum serviceable limit:
Two, for concave or convex side, 0.100 inch (2.54 mm) below the tip, no separation between any two nose holes, internal cavity of the blade cannot be seen.
Repair method:
Replace the stage 2 blade.
Subtask 72-00-00-220-318
(b)Axial cracks:
Maximum serviceable limit:
Any amount, 0.500 inch (12.70 mm).
Repair method:
Replace the stage 2 blade.
Subtask 72-00-00-220-319
(c)Bent or curled blade tips:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the stage 2 blade.
Subtask 72-00-00-220-320
(d)Missing metal and tears:
Maximum serviceable limit:
Any amount if:
• Tip cavity shelf cannot be seen
• Opposite cavity wall is not missing
• Only one area on each cavity wall has damage of 0.30 inch (7.62 mm) in length.
Repair method:
Replace the stage 2 blade.
Subtask 72-00-00-220-321
(e)Buildup of second stage shroud material:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the stage 2 blade.
* * * FOR ALL
Figure 217   Stage 1 Blade
* * * FOR ALL
Figure 218   (Sheet 1 ) Stage 2 Nozzle and Blade
* * * FOR ALL
Figure 218   (Sheet 2 ) Stage 2 Nozzle and Blade
* * * FOR ALL
Figure 218   (Sheet 3 ) Stage 2 Nozzle and Blade
Subtask 72-00-00-220-322
T.Do an inspection of the LPT stage 1 blades. Refer to Figure 219.
(1)All areas for:
(a)Metal deposit:
Maximum serviceable limit:
Any amount, within 0.00064 cu in. (10.49 cu mm) in volume.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-725
* * * FOR ALL.ALL
(a).A.Metal splatter:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-700
(b)Corrosion on the airfoil, tip and root radius:
Maximum serviceable limit:
Any amount, if there is no missing, chipping, and peeling of coating.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-701
(c)Corrosion on the platform and angel wing (does not include tip and root radius):
Maximum serviceable limit:
Any amount.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-323
(2)Shroud gas path (does not include blade tip fillet radius, fillet in area Z, and shroud lock) for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-324
(b)Nicks and scratches:
Maximum serviceable limit:
Any amount 0.020 inch (0.51 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-325
(c)Dents:
Maximum serviceable limit:
• Any amount 0.010 inch (0.25 mm) in depth
• Three dents, 0.030 inch (0.76 mm) in depth, on each side (shroud on airfoil convex and shroud on airfoil concave side).
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-756
* * * FOR ALL.ALL
(d)Bending on trailing edge:
Maximum serviceable limit:
Up to three blades, with no more than 0.121 inch (3.0 mm) out of the usual contour.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-326
(3)Leading edge (does not include area Z) for:
NOTE:
Leading edge limits cover damages that start from the leading edge and transit to the airfoil area.
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-327
(b)Tears:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-328
(c)Nicks, scores, scratches, and pittings:
Maximum serviceable limit:
Any amount 0.015 inch (0.38 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-329
(d)Dents:
Maximum serviceable limit:
• Any amount, if dents do not go through the opposite side of the blade
• Three dents are permitted, if distortion is less than 0.025 inch (0.64 mm) on the opposite side of the blade.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-330
(4)Leading edge in area Z (does not include tip and root radius) for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-331
(b)Tears:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-332
(c)Nicks, scores, scratches, and pittings:
Maximum serviceable limit:
Any amount 0.005 inch (0.13 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-333
(d)Dents:
Maximum serviceable limit:
Any amount, for each side with protrusions on the opposite side are permitted, if they are not more than 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-334
(e)Deleted.
Subtask 72-00-00-220-389
(5)Trailing edge (does not include blade tip and blade root fillet radiuses) for:
NOTE:
Trailing edge limits cover damages that start from the trailing edge and transit to the airfoil area. The depth of damage is measured from the trailing edge to the middle of the airfoil (axially).
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.).
Subtask 72-00-00-220-390
(b)Tears:
Maximum serviceable limit:
Not serviceable.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.).
Subtask 72-00-00-220-391
(c)Nicks:
Maximum serviceable limit:
Any amount 0.040 inch (1.02 mm) in depth.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.).
Subtask 72-00-00-220-726
* * * FOR ALL.ALL
(c).A.Scores, scratches, and pitting:
Maximum serviceable limit:
Any amount, 0.005 inch (0.13 mm) in depth.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.)
Subtask 72-00-00-220-392
(d)Dents:
Maximum serviceable limit:
• Any amount, if dents do not go through the opposite side of the blade
• Five dents, if distortion is less than 0.055 inch (1.40 mm) on the opposite side of the blade.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.).
Subtask 72-00-00-220-393
(e)Deleted.
Maximum serviceable limit:
Deleted.
Repair method:
Deleted.
Subtask 72-00-00-220-394
(6)Tip and root fillet radiuses for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-395
(b)Nicks scratches, scores, and pits:
Maximum serviceable limit:
Any amount 0.005 inch (0.13 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-396
(c)Dents:
Maximum serviceable limit:
Any amount 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-397
(d)Deleted.
Subtask 72-00-00-220-398
(7)Airfoil concave and convex surfaces (does not include blade tip and blade root fillet radiuses) for:
NOTE:
Airfoil limits cover damages that do not transit from the airfoil area to the leading and trailing edges.
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-399
(b)Nicks and dents:
Maximum serviceable limit:
• Nicks: 0.030 inch (0.76 mm) in depth, if they cannot go through to the opposite side of the blade
• Dents: Any amount, if dents do not go through the opposite side of the blade
• Five on each side, if distortion on opposite side is less than 0.020 inch (0.51 mm).
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-400
(8)Top surface of the platform (does not include blade root fillet radiuses) for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-401
(b)Nicks and scratches:
Maximum serviceable limit:
0.020 inch (0.51 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-727
* * * FOR ALL.ALL
(b).A.Dents:
Maximum serviceable limit:
• Any amount, 0.020 inch (0.51 mm) in depth
• Three dents, 0.030 inch (0.76 mm) in depth on each side.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-402
(c)Deleted.
Subtask 72-00-00-220-403
(1)Forward and aft angel wings for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-404
(b)Nicks and scratches:
Maximum serviceable limit:
Any amount, 0.020 inch (0.51 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-742
* * * FOR ALL.ALL
(c)Dents:
Maximum serviceable limit:
• Any amount, 0.020 inch (0.51 mm) in depth
• Three dents, 0.030 inch (0.76 mm) in depth on each side.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-405
(d)Missing, rubbed, or twisted material:
Maximum serviceable limit:
Any amount, if 50 percent of the initial material remains.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-406
(e)Deleted.
Subtask 72-00-00-220-407
U.Do an inspection of the stage 1 LPT blade shroud. Refer to Figure 221.
(1)Circumferential mate faces for:
(a)Signs of wear (irregular or jagged):
Maximum serviceable limit:
Any amount, if there are no signs of wear on the shroud interlock.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-408
(2)Shroud interlocks for:
(a)Wear:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-409
(b)Shingling or disconnected tip shrouds:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-410
  (c)Interlock gap:
  NOTE:
Deleted.
  Maximum serviceable limit:
Any amount, if there is no wear on the interlock.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-411
V.Do an inspection of the LPT stage 2 blades. Refer to Figure 219.
(1)All areas for:
(a)Metal deposit:
Maximum serviceable limit:
Any amount, within 0.00064 cu in. (10.49 cu mm) in volume.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-728
* * * FOR ALL.ALL
(a).A.Metal splatter:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-702
(b)Corrosion on the airfoil, tip and root radius:
Maximum serviceable limit:
Any amount, if there is no missing, chipping, and peeling of coating.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-703
(c)Corrosion on the platform and angel wing (does not include tip and root radius):
Maximum serviceable limit:
Any amount.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-412
(2)Shroud gas path (does not include blade tip fillet radius, fillet in area Z, and shroud interlock) for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-413
(b)Nicks and scratches:
Maximum serviceable limit:
Any amount 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-414
(c)Dents:
Maximum serviceable limit:
• Any amount 0.010 inch (0.25 mm) in depth
• Three dents, 0.020 inch (0.51 mm) in depth, on each side (shroud on airfoil convex and shroud on airfoil concave side).
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-415
(3)Leading edge (does not include area Z) for:
NOTE:
Leading edge limits cover damages that start from the leading edge and transit to the airfoil area.
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.).
Subtask 72-00-00-220-416
(b)Tears:
Maximum serviceable limit:
Not serviceable.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.).
Subtask 72-00-00-220-417
(c)Nicks, scores, scratches, and pittings:
Maximum serviceable limit:
Any amount, 0.015 inch (0.38 mm) in depth.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.).
Subtask 72-00-00-220-418
(d)Dents:
Maximum serviceable limit:
• Any amount, if they do not go through the opposite of the blade
• Three dents are permitted, if distortion is less than 0.025 inch (0.64 mm) on the opposite side of the blade.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.).
Subtask 72-00-00-220-419
(4)Leading edge in area Z (does not include tip and root radius) for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-420
(b)Tears:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-421
(c)Nicks, scores, scratches, and pittings:
Maximum serviceable limit:
Any amount 0.005 inch (0.13 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-422
(d)Dents:
Maximum serviceable limit:
Any amount, for each side with protrusions on the opposite side are permitted, if they are not more than 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-423
(e)Deleted.
Subtask 72-00-00-220-424
(5)Trailing edge (does not include blade tip and blade root fillet radiuses) for:
NOTE:
Trailing edge limits cover damages that start from the trailing edge and transit to the airfoil area. The depth of damage is measured from the trailing edge to the middle of the airfoil (axially).
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-425
(b)Tears:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-426
(c)Nicks:
Maximum serviceable limit:
Any amount 0.040 inch (1.02 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-729
* * * FOR ALL.ALL
(c).A.Scores, scratches, and pitting:
Maximum serviceable limit:
Any amount, 0.005 inch (0.13 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-427
(d)Dents:
Maximum serviceable limit:
• Any amount, if dents do not go through the opposite side of the blade
• Five dents, if distortion is less than 0.055 inch (1.40 mm) on the opposite side of the blade.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-428
(e)Deleted.
Maximum serviceable limit:
Deleted.
Repair method:
Deleted.
Subtask 72-00-00-220-429
(6)Tip and root fillet radiuses for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-430
(b)Nicks, scratches, scores, and pits:
Maximum serviceable limit:
Any amount 0.005 inch (0.13 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-431
(c)Dents:
Maximum serviceable limit:
Any amount 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-432
(d)Deleted.
Subtask 72-00-00-220-433
(7)Airfoil concave and convex surfaces (does not include blade tip and blade root fillet radiuses) for:
NOTE:
Airfoil limits cover damages that do not transit from the airfoil area to the leading and trailing edges.
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-434
(b)Nicks and dents:
Maximum serviceable limit:
• Nicks: 0.030 inch (0.76 mm) in depth, if they cannot go through to the opposite side of the blade
• Dents: Any amount, if dents do not go through the opposite side of the blade
• Five on each side, if distortion on opposite side is less than 0.020 inch (0.51 mm).
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-435
(8)Top surface of the platform (does not include blade root fillet radiuses) for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-436
(b)Nicks and dents:
Maximum serviceable limit:
0.020 inch (0.51 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-730
* * * FOR ALL.ALL
(c)Scratches:
Maximum serviceable limit:
Any amount, 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-437
(d)Deleted.
Subtask 72-00-00-220-438
(9)Forward and aft angel wings for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-439
(b)Nicks, dents, and scratches:
Maximum serviceable limit:
0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-440
(c)Missing, rubbed, or twisted material:
Maximum serviceable limit:
Any amount, if 50 percent of the initial material remains.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-441
(d)Deleted.
Subtask 72-00-00-220-442
W.Do an inspection of the stage 2 LPT blade shroud. Refer to Figure 221.
(1)Circumferential mate faces for:
(a)Signs of wear (irregular or jagged):
Maximum serviceable limit:
Any amount, if there are no signs of wear on the shroud interlock.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-443
(2)Shroud interlocks for:
(a)Wear:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-444
(b)Shingling or disconnected tip shrouds:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-445
  (c)Interlock gap:
  NOTE:
Deleted.
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-446
X.Do an inspection of the LPT stage 3 blades. Refer to Figure 219.
(1)All areas for:
(a)Metal deposit:
Maximum serviceable limit:
Any amount, within 0.00064 cu in. (10.49 cu mm) in volume.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-731
* * * FOR ALL.ALL
(a).A.Metal splatter:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-704
(b)Corrosion on the airfoil, tip and root radius:
Maximum serviceable limit:
Any amount, if there is no missing, chipping, and peeling of coating.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-705
(c)Corrosion on the platform and angel wing (does not include tip and root radius):
Maximum serviceable limit:
Any amount.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-447
(2)Shroud gas path (does not include blade tip fillet radius, fillet in area Z, and shroud interlock) for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-448
(b)Nicks and scratches:
Maximum serviceable limit:
Any amount 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-449
(c)Dents:
Maximum serviceable limit:
• Any amount 0.010 inch (0.25 mm) in depth
• Three dents, 0.020 inch (0.51 mm) in depth, on each side (shroud on airfoil convex and shroud on airfoil concave side).
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-757
* * * FOR ALL.ALL
(d)Bending on trailing edge:
Maximum serviceable limit:
Up to three blades, with no more than 0.121 inch (3.0 mm) out of the usual contour.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-450
(3)Leading edge (does not include area Z) for:
NOTE:
Leading edge limits cover damages that start from the leading edge and transit to the airfoil area.
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-451
(b)Tears:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-452
(c)Nicks, scores, scratches, and pittings:
Maximum serviceable limit:
Any amount, 0.015 inch (0.38 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-453
(d)Dents:
Maximum serviceable limit:
• Any amount, if they do not go through the opposite side of the blade
• Three dents are permitted, if distortion is less than 0.025 inch (0.64 mm) on the opposite side of the blade.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-454
(4)Leading edge in area Z (does not include tip and root radius) for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-455
(b)Tears:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-456
(c)Nicks, scores, scratches, and pittings:
Maximum serviceable limit:
Any amount 0.005 inch (0.13 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-457
(d)Dents:
Maximum serviceable limit:
Any amount, for each side with protrusions on the opposite side are permitted, if they are not more than 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-458
(e)Deleted.
Subtask 72-00-00-220-459
(5)Trailing edge (does not include blade tip and blade root fillet radiuses) for:
NOTE:
Trailing edge limits cover damages that start from the trailing edge and transit to the airfoil area. The depth of damage is measured from the trailing edge to the middle of the airfoil (axially).
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.) .
Subtask 72-00-00-220-460
(b)Tears:
Maximum serviceable limit:
Not serviceable.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.).
Subtask 72-00-00-220-461
(c)Nicks:
Maximum serviceable limit:
Any amount 0.040 inch (1.02 mm) in depth.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.).
Subtask 72-00-00-220-732
* * * FOR ALL.ALL
(c).A.Scores, scratches, and pitting:
Maximum serviceable limit:
Any amount, 0.005 inch (0.13 mm) in depth.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.) .
Subtask 72-00-00-220-462
(d)Dents:
Maximum serviceable limit:
• Any amount, if dents do not go through the opposite side of the blade
• Five dents, if distortion is less than 0.055 inch (1.40 mm) on the opposite side of the blade.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.).
Subtask 72-00-00-220-463
(e)Deleted.
Maximum serviceable limit:
Deleted.
Repair method:
Deleted.
Subtask 72-00-00-220-464
(6)Tip and root fillet radiuses for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-465
(b)Nicks, scratches, scores, and pits:
Maximum serviceable limit:
Any amount 0.005 inch (0.13 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-466
(c)Dents:
Maximum serviceable limit:
Any amount 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-467
(d)Deleted.
Subtask 72-00-00-220-468
(7)Airfoil concave and convex surfaces (does not include blade tip and blade root fillet radiuses) for:
NOTE:
Airfoil limits cover damages that do not transit from the airfoil area to the leading and trailing edges.
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-469
(b)Nicks and dents:
Maximum serviceable limit:
• Nicks: 0.030 inch (0.76 mm) in depth, if they cannot go through to the opposite side of the blade
• Dents: Any amount, if dents do not go through the opposite side of the blade.
• Five on each side, if distortion on opposite side is less than 0.020 inch (0.51 mm).
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-470
(8)Top surface of the platform (does not include blade root fillet radiuses) for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-471
(b)Nicks and dents:
Maximum serviceable limit:
0.020 inch (0.51 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-733
* * * FOR ALL.ALL
(c)Scratches:
Maximum serviceable limit:
Any amount, 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-472
(d)Deleted.
Subtask 72-00-00-220-473
(9)Forward and aft angel wings for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-474
(b)Nicks, dents, and scratches:
Maximum serviceable limit:
0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-475
(c)Missing, rubbed, or twisted material:
Maximum serviceable limit:
Any amount, if 50 percent of the initial material remains.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-476
(d)Deleted.
Subtask 72-00-00-220-477
Y.Do an inspection of the stage 3 LPT blade shroud. Refer to Figure 221.
(1)Circumferential mate faces for:
(a)Signs of wear (irregular or jagged):
Maximum serviceable limit:
Any amount, if there are no signs of wear on the shroud interlock.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-478
(2)Shroud interlocks for:
(a)Wear:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-479
(b)Shingling or disconnected tip shrouds:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-480
  (c)Interlock gap:
  NOTE:
Deleted.
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-481
Z.Do an inspection of the LPT stage 4 blades. Refer to Figure 219.
(1)All areas for:
(a)Metal deposit:
Maximum serviceable limit:
Any amount, within 0.00064 cu in. (10.49 cu mm) in volume.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-734
* * * FOR ALL.ALL
(a).A.Metal splatter:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-706
(b)Corrosion on the airfoil, tip and root radius:
Maximum serviceable limit:
Any amount, if there is no missing, chipping, and peeling of coating.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-707
(c)Corrosion on the platform and angel wing (does not include tip and root radius):
Maximum serviceable limit:
Any amount.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-482
(2)Shroud gas path (does not include blade tip fillet radius, fillet in area Z, and shroud interlock) for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-483
(b)Nicks and scratches:
Maximum serviceable limit:
Any amount 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-484
(c)Dents:
Maximum serviceable limit:
• Any amount 0.010 inch (0.25 mm) in depth
• Three dents, 0.020 inch (0.51 mm) in depth, on each side (shroud on airfoil convex and shroud on airfoil concave side).
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-758
* * * FOR ALL.ALL
(d)Rub:
Maximum serviceable limit:
Any amount, 0.004 inch (0.10 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-485
(3)Leading edge (does not include area Z) for:
NOTE:
Leading edge limits cover damages that start from the leading edge and transit to the airfoil area.
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.) .
Subtask 72-00-00-220-486
(b)Tears:
Maximum serviceable limit:
Not serviceable.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.).
Subtask 72-00-00-220-487
(c)Nicks, scores, scratches, and pittings:
Maximum serviceable limit:
Any amount, 0.015 inch (0.38 mm) in depth.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.).
Subtask 72-00-00-220-488
(d)Dents:
Maximum serviceable limit:
• Any amount, if they do not go through the opposite side of the blade
• Three dents are permitted, if distortion is less than 0.025 inch (0.64 mm) on the opposite side of the blade.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.).
Subtask 72-00-00-220-489
(4)Leading edge in area Z (does not include tip and root radius) for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-490
(b)Tears:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-491
(c)Nicks, scores, scratches, and pittings:
Maximum serviceable limit:
Any amount 0.005 inch (0.13 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-492
(d)Dents:
Maximum serviceable limit:
Any amount, for each side with protrusions on the opposite side are permitted, if they are not more than 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-493
(e)Deleted.
Subtask 72-00-00-220-494
(5)Trailing edge (does not include blade tip and blade root fillet radiuses) for:
NOTE:
Trailing edge limits cover damages that start from the trailing edge and transit to the airfoil area. The depth of damage is measured from the trailing edge to the middle of the airfoil (axially).
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-495
(b)Tears:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-496
(c)Nicks:
Maximum serviceable limit:
Any amount 0.040 inch (1.02 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-735
* * * FOR ALL.ALL
(c).A.Scores, scratches, and pitting:
Maximum serviceable limit:
Any amount, 0.005 inch (0.13 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-497
(d)Dents:
Maximum serviceable limit:
• Any amount, if dents do not go through the opposite side of the blade
• Five dents, if distortion is less than 0.055 inch (1.40 mm) on the opposite side of the blade.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-498
(e)Deleted.
Maximum serviceable limit:
Deleted.
Repair method:
Deleted.
Subtask 72-00-00-220-499
(6)Tip and root fillet radiuses for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-500
(b)Nicks, scratches, scores, and pits:
Maximum serviceable limit:
Any amount 0.005 inch (0.13 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-501
(c)Dents:
Maximum serviceable limit:
Any amount 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-502
(d)Deleted.
Subtask 72-00-00-220-503
(7)Airfoil concave and convex surfaces (does not include blade tip and blade root fillet radiuses) for:
NOTE:
Airfoil limits cover damages that do not transit from the airfoil area to the leading and trailing edges.
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-504
(b)Nicks and dents:
Maximum serviceable limit:
• Nicks: 0.030 inch (0.76 mm) in depth, if they cannot go through to the opposite side of the blade.
• Dents: Any amount, if dents do not go through the opposite side of the blade.
• Five on each side, if distortion on opposite side is less than 0.020 inch (0.51 mm).
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-505
(8)Top surface of the platform (does not include blade root fillet radiuses) for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-506
(b)Nicks and dents:
Maximum serviceable limit:
0.020 inch (0.51 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-736
* * * FOR ALL.ALL
(c)Scratches:
Maximum serviceable limit:
Any amount, 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-507
(d)Deleted.
Subtask 72-00-00-220-508
(9)Forward and aft angel wings for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-509
(b)Nicks and dents:
Maximum serviceable limit:
0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-510
(c)Missing, rubbed, or twisted material:
Maximum serviceable limit:
Any amount, if 50 percent of the initial material remains.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-511
(d)Deleted.
Subtask 72-00-00-220-512
AA.Do an inspection of the stage 4 LPT blade shroud. Refer to Figure 221.
(1)Circumferential mate faces for:
(a)Signs of wear (irregular or jagged):
Maximum serviceable limit:
Any amount, if there are no signs of wear on the shroud interlock.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-513
(2)Shroud interlocks for:
(a)Wear:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-514
(b)Shingling or disconnected tip shrouds:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-515
  (c)Interlock gap:
  NOTE:
Deleted.
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-516
AB.Do an inspection of the LPT stage 5 blades. Refer to Figure 219.
(1)All areas for:
(a)Metal deposit:
Maximum serviceable limit:
Any amount, within 0.00064 cu in. (10.49 cu mm) in volume.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-737
* * * FOR ALL.ALL
(a).A.Metal splatter:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-708
(b)Corrosion on the airfoil tip and root radius. Refer to Figure 219 as follows:
Maximum serviceable limit:
Any amount, if there is no missing, chipping, and peeling of coating.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-709
(c)Corrosion on the platform and angel wing (does not include tip and root radius). Refer to Figure 219 as follows:
Maximum serviceable limit:
Any amount, if there is no missing, chipping, and peeling of coating.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-517
(2)Shroud gas path (does not include blade tip fillet radius, fillet in area Z, and shroud interlock) for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-518
(b)Nicks and scratches:
Maximum serviceable limit:
Any amount 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-519
(c)Dents:
Maximum serviceable limit:
• Any amount 0.010 inch (0.25 mm) in depth
• Three dents, 0.020 inch (0.51 mm) in depth, on each side (shroud on airfoil convex and shroud on airfoil concave side).
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-759
* * * FOR ALL.ALL
(d)Bending on trailing edge:
Maximum serviceable limit:
Up to three blades, with no more than 0.121 inch (3.0 mm) out of the usual contour.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-520
(3)Leading edge (does not include area Z) for:
NOTE:
Leading edge limits cover damages that start from the leading edge and transit to the airfoil area.
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-521
(b)Tears:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-522
(c)Nicks, scores, scratches, and pittings:
Maximum serviceable limit:
Any amount, 0.015 inch (0.38 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-523
(d)Dents:
Maximum serviceable limit:
• Any amount, if they do not go through the opposite side of the blade
• Three dents are permitted, if distortion is less than 0.025 inch (0.64 mm) on the opposite side of the blade.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-524
(4)Leading edge in area Z (does not include tip and root radius) for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-525
(b)Tears:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-526
(c)Nicks, scores, scratches, and pittings:
Maximum serviceable limit:
Any amount 0.005 inch (0.13 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-527
(d)Dents:
Maximum serviceable limit:
Any amount, for each side with protrusions on the opposite side are permitted, if they are not more than 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-528
(e)Deleted.
Subtask 72-00-00-220-529
(5)Trailing edge (does not include blade tip and blade root fillet radiuses) for:
NOTE:
Trailing edge limits cover damages that start from the trailing edge and transit to the airfoil area. The depth of damage is measured from the trailing edge to the middle of the airfoil (axially).
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.) .
Subtask 72-00-00-220-530
(b)Tears:
Maximum serviceable limit:
Not serviceable.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.).
Subtask 72-00-00-220-531
(c)Nicks:
Maximum serviceable limit:
Any amount 0.040 inch (1.02 mm) in depth.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.).
Subtask 72-00-00-220-738
* * * FOR ALL.ALL
(c).A.Scores, scratches, and pitting:
Maximum serviceable limit:
Any amount, 0.005 inch (0.13 mm) in depth.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.) .
Subtask 72-00-00-220-532
(d)Dents:
Maximum serviceable limit:
• Any amount, if dents do not go through the opposite side of the blade
• Five dents, if distortion is less than 0.055 inch (1.40 mm) on the opposite side of the blade.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.).
Subtask 72-00-00-220-533
(e)Deleted.
Maximum serviceable limit:
Deleted.
Repair method:
Deleted.
Subtask 72-00-00-220-534
(6)Tip and root fillet radiuses for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-535
(b)Nicks, scratches, scores, and pits:
Maximum serviceable limit:
Any amount 0.005 inch (0.13 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-536
(c)Dents:
Maximum serviceable limit:
Any amount 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-537
(d)Deleted.
Subtask 72-00-00-220-538
(7)Airfoil concave and convex surfaces (does not include blade tip and blade root fillet radiuses) for:
NOTE:
Airfoil limits cover damages that do not transit from the airfoil area to the leading and trailing edges.
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-539
(b)Nicks and dents:
Maximum serviceable limit:
• Nicks: 0.030 inch (0.76 mm) in depth, if they cannot go through to the opposite side of the blade
• Dents: Any amount, if dents do not go through the opposite side of the blade
• Five on each side, if distortion on opposite side is less than 0.020 inch (0.51 mm).
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-540
(8)Top surface of the platform (does not include blade root fillet radiuses) for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-541
(b)Nicks and dents:
Maximum serviceable limit:
0.020 inch (0.51 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-739
* * * FOR ALL.ALL
(c)Scratches:
Maximum serviceable limit:
Any amount, 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-542
(d)Deleted.
Subtask 72-00-00-220-543
(9)Forward and aft angel wings for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-544
(b)Nicks, dents, and scratches:
Maximum serviceable limit:
0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-545
(c)Missing, rubbed, or twisted material:
Maximum serviceable limit:
Any amount, if 50 percent of the initial material remains.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-546
(d)Deleted.
Subtask 72-00-00-220-547
AC.Do an inspection of the stage 5 LPT blade shroud. Refer to Figure 221.
(1)Circumferential mate faces for:
(a)Signs of wear (irregular or jagged):
Maximum serviceable limit:
Any amount, if there are no signs of wear on the shroud interlock.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-548
(2)Shroud interlocks for:
(a)Wear:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-549
(b)Shingling or disconnected tip shrouds:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-550
  (c)Interlock gap:
  NOTE:
Deleted.
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-551
CAUTION:
THE STAGE 6 LPT BLADES ARE MANUFACTURED FROM A TITANIUM ALUMINIDE MATERIAL, WHICH IS RELATIVELY BRITTLE AT ROOM TEMPERATURE. PERFORM THE BORESCOPE CAREFULLY, DAMAGE TO THE BLADE CAN OCCUR.
AD.Do an inspection of the LPT stage 6 blades. Refer to Figure 219.
(1)All areas for:
(a)Metal deposit:
Maximum serviceable limit:
Any amount, within 0.00064 cu in. (10.49 cu mm) in volume.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-740
* * * FOR ALL.ALL
(b)Metal splatter:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-552
(2)Shroud gas path (does not include blade tip fillet radius, fillet in area Z, and shroud lock) for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-553
(b)Nicks and scratches:
Maximum serviceable limit:
Any amount 0.005 inch (0.13 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-554
(c)Dents:
Maximum serviceable limit:
Any amount 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-555
(3)Leading edge (does not include area Z) for:
NOTE:
Leading edge limits cover damages that start from the leading edge and transit to the airfoil area.
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.) .
Subtask 72-00-00-220-556
(b)Tears:
Maximum serviceable limit:
Not serviceable.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.).
Subtask 72-00-00-220-557
(c)Nicks, scores, scratches, and pittings:
Maximum serviceable limit:
Any amount 0.002 inch (0.05 mm) in depth.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.).
Subtask 72-00-00-220-558
(d)Dents:
Maximum serviceable limit:
Any amount 0.010 inch (0.25 mm) in depth.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.).
Subtask 72-00-00-220-760
* * * FOR ALL.ALL
(e)Missing material:
Maximum serviceable limit:
Not serviceable.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.) .
Subtask 72-00-00-220-559
(4)Leading edge in area Z (includes shroud/leading edge fillet radius and platform/leading edge fillet radius) for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-560
(b)Tears:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-561
(c)Nicks, scores, scratches, and pittings:
Maximum serviceable limit:
Any amount 0.002 inch (0.05 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-562
(d)Dents:
Maximum serviceable limit:
Any amount 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-761
* * * FOR ALL.ALL
(e)Missing material:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-563
(5)Trailing edge (does not include blade tip and blade root fillet radiuses) for:
NOTE:
Trailing edge limits cover damages that start from the trailing edge and transit to the airfoil area. The depth of damage is measured from the trailing edge to the middle of the airfoil (axially).
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-564
(b)Tears:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-565
(c)Nicks:
Maximum serviceable limit:
Any amount 0.002 inch (0.05 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-566
(d)Dents:
Maximum serviceable limit:
Any amount 0.010 inch (0.25 mm) in depth, if dents do not go through the opposite side of the blade.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-762
* * * FOR ALL.ALL
(e)Missing material:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-567
(6)Airfoil, tip, and root fillet radiuses (does not include area Z) for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-568
(b)Nicks and scratches:
Maximum serviceable limit:
Any amount 0.002 inch (0.05 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-569
(c)Dents:
Maximum serviceable limit:
Any amount 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-570
(7)Airfoil concave and convex surfaces (does not include blade tip and blade root fillet radiuses) for:
NOTE:
Airfoil limits cover damages that do not transit from the airfoil area to the leading and trailing edges.
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-571
(b)Nicks:
Maximum serviceable limit:
0.003 inch (0.08 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-572
(c)Dents:
Maximum serviceable limit:
0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-573
(8)Top surface of the platform (does not include blade root fillet radiuses) for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-574
(b)Nicks:
Maximum serviceable limit:
0.005 inch (0.13 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-575
(c)Dents:
Maximum serviceable limit:
0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-576
(9)Forward and aft angel wings for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-577
(b)Nicks:
Maximum serviceable limit:
0.005 inch (0.13 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-578
(c)Dents:
Maximum serviceable limit:
0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-579
(d)Missing, rubbed, or twisted material:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-580
AE.Do an inspection of the stage 6 LPT blade shroud. Refer to Figure 221.
(1)Circumferential mate faces for:
(a)Signs of wear (irregular or jagged):
Maximum serviceable limit:
Any amount, if there are no signs of wear on the interlock area of the mate face.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-581
(2)Shroud interlocks for:
(a)Wear:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-582
(b)Shingling or disconnected tip shrouds:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-583
  (c)Interlock gap:
  NOTE:
Deleted.
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-584
CAUTION:
THE STAGE 7 LPT BLADES ARE MANUFACTURED FROM A TITANIUM ALUMINIDE MATERIAL, WHICH IS RELATIVELY BRITTLE AT ROOM TEMPERATURE. PERFORM THE BORESCOPE CAREFULLY, DAMAGE TO THE BLADE CAN OCCUR.
AF.Do an inspection of the LPT stage 7 blades. Refer to Figure 219.
(1)All areas for:
(a)Metal deposit:
Maximum serviceable limit:
Any amount, within 0.00064 cu in. (10.49 cu mm) in volume.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-741
* * * FOR ALL.ALL
(b)Metal splatter:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-585
(2)Shroud gas path (does not include blade tip fillet radius and fillet in area Z) for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-586
(b)Nicks and scratches:
Maximum serviceable limit:
Any amount 0.005 inch (0.13 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-587
(c)Dents:
Maximum serviceable limit:
Any amount 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-588
(3)Leading edge (does not include area Z) for:
NOTE:
Leading edge limits cover damages that start from the leading edge and transit to the airfoil area.
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-589
(b)Tears:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-590
(c)Nicks, scores, scratches, and pittings:
Maximum serviceable limit:
Any amount 0.002 inch (0.05 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-591
(d)Dents:
Maximum serviceable limit:
Any amount 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-763
* * * FOR ALL.ALL
(e)Missing material:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-592
(4)Leading edge in area Z (includes shroud/leading edge fillet radius and platform/leading edge fillet radius) for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-593
(b)Tears:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-594
(c)Nicks, scores, scratches, and pittings:
Maximum serviceable limit:
Any amount 0.002 inch (0.05 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-595
(d)Dents:
Maximum serviceable limit:
Any amount 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-764
* * * FOR ALL.ALL
(e)Missing material:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-596
(5)Trailing edge (does not include blade tip and blade root fillet radiuses) for:
NOTE:
Trailing edge limits cover damages that start from the trailing edge and transit to the airfoil area. The depth of damage is measured from the trailing edge to the middle of the airfoil (axially).
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.) .
Subtask 72-00-00-220-597
(b)Tears:
Maximum serviceable limit:
Not serviceable.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.).
Subtask 72-00-00-220-598
(c)Nicks:
Maximum serviceable limit:
Any amount 0.002 inch (0.05 mm) in depth.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.).
Subtask 72-00-00-220-599
(d)Dents:
Maximum serviceable limit:
Any amount 0.010 inch (0.25 mm) in depth, if dents do not go through the opposite side of the blade.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.).
Subtask 72-00-00-220-765
* * * FOR ALL.ALL
(e)Missing material:
Maximum serviceable limit:
Not serviceable.
Repair method:
Blend. Refer to Subtask 72-00-00-350-012 (paragraph 7.A.) .
Subtask 72-00-00-220-600
(6)Airfoil, tip, and root fillet radiuses (does not include area Z) for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-601
(b)Nicks and scratches:
Maximum serviceable limit:
Any amount 0.002 inch (0.05 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-602
(c)Dents:
Maximum serviceable limit:
Any amount 0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-603
(7)Airfoil concave and convex surfaces (does not include blade tip and blade root fillet radiuses) for:
NOTE:
Airfoil limits cover damages that do not transit from the airfoil area to the leading and trailing edges.
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-604
(b)Nicks:
Maximum serviceable limit:
0.003 inch (0.08 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-605
(c)Dents:
Maximum serviceable limit:
0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-606
(8)Top surface of the platform (does not include blade root fillet radiuses, unless specified differently) for:
(a)Cracks:
Maximum serviceable limit:
Any indication up to 0.060 inch (1.52 mm) in length, within area W. Not serviceable outside area W.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-607
(b)Nicks and chips:
Maximum serviceable limit:
Any amount within area W. 0.010 inch (0.25 mm) in depth, outside area W.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-608
(c)Dents:
Maximum serviceable limit:
0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-609
(9)Forward and aft angel wings for:
(a)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-610
(b)Nicks:
Maximum serviceable limit:
0.005 inch (0.13 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-611
(c)Dents:
Maximum serviceable limit:
0.010 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-612
(d)Missing, rubbed, or twisted material:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-613
AG.Do an inspection of the stage 7 LPT blade shroud. Refer to Figure 221.
(1)Circumferential mate faces for:
(a)Signs of wear (irregular or jagged):
Maximum serviceable limit:
Any amount, if there are no signs of wear on the interlock area of the mate face.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-614
(2)Shroud interlocks for:
(a)Wear:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-615
(b)Shingling or disconnected tip shrouds:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-616
  (c)Interlock gap:
  NOTE:
Deleted.
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-617
AH.Do an inspection of the stage 2 LPT nozzles. Refer to Figure 221.
NOTE:
Limits for nozzles were added to address damages of nozzle areas accessible during borescope inspection (the one with borescope hole). Full 360 degree inspection of the LPT nozzles is very difficult and it is not necessary.
(1)Cracks (all areas, in parent metal):
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-618
(2)Nicks or dents on the airfoil (does not include fillet radiuses with platforms):
Maximum serviceable limit:
0.031 inch (0.78 mm) in depth, if they cannot go through to the opposite side of the blade.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-619
(3)Nicks or dents on the leading and trailing edges (does not include area X and area Z):
Maximum serviceable limit:
Any amount 0.050 inch (1.27 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-620
* * * PRE SB   72-0160
(4)Nicks or dents on the leading and trailing edges in area X:
Maximum serviceable limit:
Any amount 0.003 inch (0.07 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
* * * END PRE SB   72-0160
Subtask 72-00-00-220-715
* * * FOR ALL.ALL
* * * SB   72-0160
(5)Nick or dents on the leading and trailing edges in area X:
Maximum serviceable limit:
Any amount, 0.035 inch (0.9 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
* * * END SB   72-0160
Subtask 72-00-00-220-621
(6)Nicks or dents on the leading and trailing edges in area Z:
Maximum serviceable limit:
Any amount 0.039 inch (0.99 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-622
(7)Nicks or dents on inner and outer platforms (does not include fillet radiuses with airfoil and does not include area Z and area X):
Maximum serviceable limit:
Any amount 0.005 inch (0.13 mm).
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-623
* * * PRE SB   72-0160
(8)Nicks or dents in airfoil fillet radiuses (does not include area Z and area X):
Maximum serviceable limit:
Any amount 0.003 inch (0.07 mm).
Repair method:
Replace the rotor/stator assembly.
* * * END PRE SB   72-0160
Subtask 72-00-00-220-716
* * * FOR ALL.ALL
* * * SB   72-0160
(9)Nick or dents in airfoil fillet radiuses (does not include area Z and area X):
Maximum serviceable limit:
Any amount, 0.020 inch (0.5 mm).
Repair method:
Replace the rotor/stator assembly.
* * * END SB   72-0160
Subtask 72-00-00-220-624
(10)Corrosion:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-625
AI.Do an inspection of the stage 4 LPT nozzles. Refer to Figure 221.
NOTE:
Limits for nozzles were added to address damages of nozzle areas accessible during borescope inspection (the one with borescope hole). Full 360 degree inspection of the LPT nozzles is very difficult and it is not necessary.
(1)Cracks (all areas, in parent metal):
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-626
(2)Nicks or dents on the airfoil (does not include fillet radiuses with platforms):
Maximum serviceable limit:
0.020 inch (0.51 mm) in depth, if they cannot go through to the opposite side of the blade.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-627
(3)Nicks or dents on the leading and trailing edges (does not include area X and area Z):
Maximum serviceable limit:
Any amount 0.020 inch (0.51 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-628
* * * PRE SB   72-0160
(4)Nicks or dents on the leading and trailing edges in area X:
Maximum serviceable limit:
Any amount 0.003 inch (0.07 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-629
(5)Nicks or dents on the leading and trailing edges in area Z:
Maximum serviceable limit:
Any amount 0.020 inch (0.051 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
* * * END PRE SB   72-0160
Subtask 72-00-00-220-717
* * * FOR ALL.ALL
* * * SB   72-0160
(6)Nicks or dents on the leading and trailing edges in area X:
Maximum serviceable limit:
Any amount, 0.01 inch (0.25 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-718
* * * FOR ALL.ALL
(7)Nicks or dents on the leading and trailing edges in area Z:
Maximum serviceable limit:
Any amount, 0.05 inch (1.27 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
* * * END SB   72-0160
Subtask 72-00-00-220-630
(8)Nicks or dents on inner and outer platforms (does not include fillet radiuses with airfoil and does not include area Z and area X):
Maximum serviceable limit:
Any amount 0.005 inch (0.13 mm).
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-631
* * * PRE SB   72-0160
(9)Nicks or dents in airfoil fillet radiuses (does not include area Z and area X):
Maximum serviceable limit:
Any amount 0.003 inch (0.07 mm).
Repair method:
Replace the rotor/stator assembly.
* * * END PRE SB   72-0160
Subtask 72-00-00-220-719
* * * FOR ALL.ALL
* * * SB   72-0160
(10)Nicks or dents in airfoil fillet radiuses (does not include area X and area Z):
Maximum serviceable limit:
Any amount, 0.020 inch (0.5 mm).
Repair method:
Replace the rotor/stator assembly.
* * * END SB   72-0160
Subtask 72-00-00-220-632
(11)Corrosion:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-633
AJ.Do an inspection of the stage 6 LPT nozzles. Refer to Figure 221.
NOTE:
Limits for nozzles were added to address damages of nozzle areas accessible during borescope inspection (the one with borescope hole). Full 360 degree inspection of the LPT nozzles is very difficult and it is not necessary.
(1)Cracks (all areas, in parent metal):
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-634
* * * PRE SB   72-0160
(2)Nicks or dents on the airfoil (does not include fillet radiuses with platforms):
Maximum serviceable limit:
0.005 inch (0.12 mm) in depth, if they cannot go through to the opposite side of the blade.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-635
(3)Nicks or dents on the leading and trailing edges (does not include area X and area Z):
Maximum serviceable limit:
Any amount 0.003 inch (0.07 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-636
(4)Nicks or dents on the leading and trailing edges in area X:
Maximum serviceable limit:
Any amount 0.003 inch (0.07 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-637
(5)Nicks or dents on the leading and trailing edges in area Z:
Maximum serviceable limit:
Any amount 0.003 inch (0.07 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
* * * END PRE SB   72-0160
Subtask 72-00-00-220-720
* * * FOR ALL.ALL
* * * SB   72-0160
(6)Nicks or dents on the airfoil (does not include fillet radiuses with platforms):
Maximum serviceable limit:
0.040 inch (1.02 mm) in depth, if they cannot go through to the opposite side of the blade.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-721
* * * FOR ALL.ALL
(7)Nicks or dents on the leading and trailing edges (does not include area X and area Z):
Maximum serviceable limit:
Any amount, 0.050 inch (1.27 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-722
* * * FOR ALL.ALL
(8)Nicks or dents on the leading and trailing edges in area X:
Maximum serviceable limit:
Any amount, 0.050 inch (1.27 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-723
* * * FOR ALL.ALL
(9)Nicks or dents on the leading and trailing edges in area Z:
Maximum serviceable limit:
Any amount, 0.050 inch (1.27 mm) in depth.
Repair method:
Replace the rotor/stator assembly.
* * * END SB   72-0160
Subtask 72-00-00-220-638
(10)Nicks or dents on inner and outer platforms (does not include fillet radiuses with airfoil and does not include area Z and area X):
Maximum serviceable limit:
Any amount 0.011 inch (0.28 mm).
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-639
* * * PRE SB   72-0160
(11)Nicks or dents in airfoil fillet radiuses (does not include area Z and area X):
Maximum serviceable limit:
Any amount 0.003 inch (0.07 mm).
Repair method:
Replace the rotor/stator assembly.
* * * END PRE SB   72-0160
Subtask 72-00-00-220-724
* * * FOR ALL.ALL
* * * SB   72-0160
(12)Nicks or dents in airfoil fillet radiuses (does not include area X and area Z):
Maximum serviceable limit:
Any amount, 0.020 inch (0.5 mm).
Repair method:
Replace the rotor/stator assembly.
* * * END SB   72-0160
Subtask 72-00-00-220-640
(13)Corrosion:
Maximum serviceable limit:
Any amount.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-766
* * * FOR ALL.ALL
AK.Do an inspection of the stage 1 LPT shrouds. Refer to Figure 222.
NOTE:
Limits for shrouds were added to address damages of shroud areas accessible during borescope inspection. Full inspection of the LPT shrouds is not necessary.
(1)Cracks on honeycomb:
Maximum serviceable limit:
Any amount is acceptable, with or without missing material, if the honeycomb stays in place, without looseness can interfere with the LPT rotor assembly.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-767
* * * FOR ALL.ALL
(2)Missing walls on honeycomb cells:
Maximum serviceable limit:
Any amount, with maximum width 0.253 inch (6.43 mm) and minimum spacing between locations more than 2.0 inch (50.8 mm).
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-768
* * * FOR ALL.ALL
AL.Do an inspection of the stage 2 LPT shrouds. Refer to Figure 222.
NOTE:
Limits for shrouds were added to address damages of shroud areas accessible during borescope inspection. Full inspection of the LPT shrouds is not necessary.
(1)Cracks on honeycomb:
Maximum serviceable limit:
Any amount is acceptable, with or without missing material, if the honeycomb stays in place, without looseness can interfere with the LPT rotor assembly.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-769
* * * FOR ALL.ALL
(2)Missing walls on honeycomb cells:
Maximum serviceable limit:
Any amount, with maximum width 0.253 inch (6.43 mm) and minimum spacing between locations more than 2.0 inch (50.8 mm).
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-770
* * * FOR ALL.ALL
AM.Do an inspection of the stage 3 LPT shrouds. Refer to Figure 222.
NOTE:
Limits for shrouds were added to address damages of shroud areas accessible during borescope inspection. Full inspection of the LPT shrouds is not necessary.
(1)Cracks on honeycomb:
Maximum serviceable limit:
Any amount is acceptable, with or without missing material, if the honeycomb stays in place, without looseness can interfere with the LPT rotor assembly.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-771
* * * FOR ALL.ALL
(2)Missing walls on honeycomb cells:
Maximum serviceable limit:
Any amount, with maximum width 0.253 inch (6.43 mm) and minimum spacing between locations more than 2.0 inch (50.8 mm).
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-772
* * * FOR ALL.ALL
AN.Do an inspection of the stage 4 LPT shrouds. Refer to Figure 222.
NOTE:
Limits for shrouds were added to address damages of shroud areas accessible during borescope inspection. Full inspection of the LPT shrouds is not necessary.
(1)Cracks on honeycomb:
Maximum serviceable limit:
Any amount is acceptable, with or without missing material, if the honeycomb stays in place, without looseness can interfere with the LPT rotor assembly.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-773
* * * FOR ALL.ALL
(2)Missing walls on honeycomb cells:
Maximum serviceable limit:
Any amount, with maximum width 0.253 inch (6.43 mm) and minimum spacing between locations more than 2.0 inch (50.8 mm).
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-774
* * * FOR ALL.ALL
AO.Do an inspection of the stage 5 LPT shrouds. Refer to Figure 222.
NOTE:
Limits for shrouds were added to address damages of shroud areas accessible during borescope inspection. Full inspection of the LPT shrouds is not necessary.
(1)Cracks on honeycomb:
Maximum serviceable limit:
Any amount is acceptable, with or without missing material, if the honeycomb stays in place, without looseness can interfere with the LPT rotor assembly.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-775
* * * FOR ALL.ALL
(2)Missing walls on honeycomb cells:
Maximum serviceable limit:
Any amount, with maximum width 0.253 inch (6.43 mm) and minimum spacing between locations more than 2.0 inch (50.8 mm).
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-776
* * * FOR ALL.ALL
AP.Do an inspection of the stage 6 LPT shrouds. Refer to Figure 222.
NOTE:
Limits for shrouds were added to address damages of shroud areas accessible during borescope inspection. Full inspection of the LPT shrouds is not necessary.
(1)Cracks on honeycomb:
Maximum serviceable limit:
Any amount is acceptable, with or without missing material, if the honeycomb stays in place, without looseness can interfere with the LPT rotor assembly.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-777
* * * FOR ALL.ALL
(2)Missing walls on honeycomb cells:
Maximum serviceable limit:
Any amount, with maximum width 0.253 inch (6.43 mm) and minimum spacing between locations more than 2.0 inch (50.8 mm).
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-778
* * * FOR ALL.ALL
AQ.Do an inspection of the stage 7 LPT shrouds. Refer to Figure 222.
NOTE:
Limits for shrouds were added to address damages of shroud areas accessible during borescope inspection. Full inspection of the LPT shrouds is not necessary.
(1)Cracks on honeycomb:
Maximum serviceable limit:
Any amount is acceptable, with or without missing material, if the honeycomb stays in place, without looseness can interfere with the LPT rotor assembly.
Repair method:
Replace the rotor/stator assembly.
Subtask 72-00-00-220-779
* * * FOR ALL.ALL
(2)Missing walls on honeycomb cells:
Maximum serviceable limit:
Any amount, with maximum width 0.253 inch (6.43 mm) and minimum spacing between locations more than 2.0 inch (50.8 mm).
Repair method:
Replace the rotor/stator assembly.
* * * FOR ALL
Figure 219   (Sheet 1 ) LPT Rotor Section Blade Inspection
* * * FOR ALL
Figure 219   (Sheet 2 ) LPT Rotor Section Blade Inspection
* * * FOR ALL
Figure 219   (Sheet 3 ) LPT Rotor Section Blade Inspection
* * * FOR ALL
Figure 219   (Sheet 4 ) LPT Rotor Section Blade Inspection
* * * FOR ALL
Figure 219   (Sheet 5 ) LPT Rotor Section Blade Inspection
* * * FOR ALL
Figure 219   (Sheet 6 ) LPT Rotor Section Blade Inspection
* * * FOR ALL
Figure 219   (Sheet 7 ) Blade Aft Platform - Inspection
* * * FOR ALL.ALL
Figure 219   (Sheet 8 ) LPT Rotor Section Blade Inspection
* * * FOR ALL.ALL
Figure 219   (Sheet 9 ) LPT Rotor Section Blade Inspection
* * * FOR ALL.ALL
Figure 219   (Sheet 10 ) LPT Rotor Section Blade Inspection
* * * FOR ALL.ALL
Figure 219   (Sheet 11 ) LPT Rotor Section Blade Inspection
* * * FOR ALL.ALL
Figure 219   (Sheet 12 ) LPT Rotor Section Blade Inspection
* * * FOR ALL.ALL
Figure 219   (Sheet 13 ) LPT Rotor Section Blade Inspection
* * * FOR ALL
Figure 220   (Sheet 1 ) LPT Nozzles Inspection
* * * FOR ALL
Figure 220   (Sheet 2 ) LPT Nozzles Inspection.
* * * FOR ALL
Figure 221   (Sheet 1 ) LPT Rotor Section Blade Shroud Circumferential Inspection
* * * FOR ALL
Figure 221   (Sheet 2 ) LPT Rotor Section Blade Shroud Circumferential Inspection
* * * FOR ALL
Figure 221   (Sheet 3 ) LPT Rotor Section Blade Shroud Circumferential Inspection
* * * FOR ALL.ALL
Figure 221   (Sheet 4 ) LPT Rotor Section Blade Shroud Circumferential Inspection
* * * FOR ALL.ALL
* * * FOR ALL.ALL
Figure 222   (Sheet 1 ) LPT Shrouds Inspection
* * * FOR ALL.ALL
Figure 222   (Sheet 2 ) LPT Shrouds Inspection
6 . Blending Procedure for the HPC Stage 1, 2, 5 Blisk and Stage 3, 4, 6, 7, 8, 9 Blades with the 11C3414 Borescope Blending Kit
Subtask 72-00-00-350-002
A.Blend stages 1, 2, and 5 HPC blisk and stages 3-4 and stages 6-9 blade as follows:
(1)Set up the 11C3414   borescope blending kit and engine to do a borescope blend to the HPC blades and blisk airfoil stages 1-9. Refer to Figure 223.
(2)Install the 11C3407   adapter . Refer to Subtask 72-00-00-040-022 (paragraph 4.F) and Subtask 72-00-00-220-353 (paragraph 4.G.).
(3)Remove the applicable borescope plug (A through I) from the high pressure compressor stator assembly. Refer to Figure 226.
(a)Put the tag on the borescope plug to identify its access port.
(4)Do a zero index of the HPC rotor. Refer to Subtask 72-00-00-220-353 (paragraph 4.G.).
(5)For blending limits refer to Subtask 72-00-00-220-079 (paragraph 5.E.) thru Subtask 72-00-00-220-164 (paragraph 5.M.) and Figure 224.
(6)Find the dimensions of the necessary blend repair as follows:
CAUTION:
INSTALL A BLENDING TOOL TIP WITH THE DRIVE SHAFT HEAD IN THE 90 DEGREE POSITION. IF THE TIP WITH THE DRIVE SHAFT HEAD IS INSTALLED IN ANY OTHER POSITION, THE DRIVE BELT WILL BECOME DISENGAGED AND DAMAGE TO THE PART CAN OCCUR.
(a)Put the drive shaft head in the 90 degree position, install the measuring grid tip, and tighten the lock screw. Refer to Figure 225 and Figure 226.
(b)Put the drive shaft head in the zero degree position.
(c)Put the borescope drive shaft head into the compressor through the applicable borescope access port.
(d)Turn ON the engine of the 11C3414   borescope blending kit.
(e)Monitor the borescope image of the measuring grid tip while moving the measuring grid tip from the zero degree to the 90 degree position.
(f)Monitor the borescope image of the measuring grid tip as follows:
1Put the measuring grid tip near each blade and blisk airfoil damaged area. Use the grid tip to find and record the dimensions of the damage as follows:
aThe maximum depth of the damaged area.
bThe maximum width of the damaged area.
cThe maximum length of the damaged area.
dThe location of the edges of the damaged area from the nearest edge of the airfoil.
(g)Find if a blend repair is permitted for each area on a blade and/or blisk as follows:
1Examine the blend repair limits for the HPC stage 1-2 and 5 blisks and stages 3-4, 6-9 blades. Refer to Subtask 72-00-00-220-079 (paragraph 5.E.) thru Subtask 72-00-00-220-164 (paragraph 5.M.) and Figure 224.
2Compare the data for the location of each damaged area to the blend repair limits.
3For each damaged area permitted to be repaired:
aOn a blade, calculate the minimum blend repair length as eight times dimension A (the maximum depth of the damage).
bOn a blisk, calculate the minimum blend repair length as six times dimension A and the maximum repair length as eight times dimension A.
cAdjust the damaged area to the center in the blend repair calculation. Refer to Figure 224 and Figure 227.
4Put the borescope drive shaft head in the zero degree position and remove the borescope shaft from the access port.
CAUTION:
REMOVE A BLENDING TOOL TIP WITH THE DRIVE SHAFT HEAD IN THE 90 DEGREE POSITION. IF THE TIP WITH THE DRIVE SHAFT HEAD IS INSTALLED IN ANY OTHER POSITION, THE DRIVE BELT WILL BECOME DISENGAGED AND DAMAGED TO THE PART CAN OCCUR.
5Put the borescope drive shaft head in the 90 degree position, loosen the lock screw, and remove the measuring grid tip. Refer to Figure 226.
CAUTION:
ONLY ONE BLEND IS PERMITTED FOR EACH BLADE OR BLISK AIRFOIL. IF YOU DO MORE THAN ONE BLEND YOU WILL DAMAGE THE AIRFOIL.
(7)Blend each blade and/or blisk airfoil damaged area that is permitted to repair as follows. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES).
(a)For limits on number of blade or blisk airfoils that can be blended per stage and how many adjacent blade or blisk airfoils can be blended per stage. Refer to Figure 224.
(b)Get the correct blending tip for the size and/or the shape of the blade and/or blisk damaged area. Refer to Figure 225.
CAUTION:
INSTALL A BLENDING TOOL TIP WITH THE DRIVE SHAFT HEAD IN THE 90 DEGREE POSITION. IF THE TIP WITH THE DRIVE SHAFT HEAD IS INSTALLED IN ANY OTHER POSITION, THE DRIVE BELT WILL BECOME DISENGAGED AND DAMAGE TO THE PART CAN OCCUR.
(c)Put the borescope drive shaft head in the 90 degree position, install the blending tip and tighten the lock screw. Refer to Figure 225 and Figure 226.
(d)Put the blending tip in the 90 degree position, turn the blending tip until it points away from you and briefly operate the motor.
1Make sure that the blending tip turns in the clockwise (CW) direction.
NOTE:
During operation, a blending tip that turns in the CW direction will be tightened by the force of the operation.
2If the blending tip turns in the counterclockwise (CCW) direction, do a check of the drive belt for a twisted installation.
aIf the drive belt is twisted, correct the belt so that it is not twisted.
bIf the belt was twisted and the blending tip turned in the CCW direction, make sure that the blending tip is not loose or disconnected from the drive shaft head.
(e)Put the drive shaft head in the zero degree position.
(f)Put the borescope drive shaft head into the compressor through the correct borescope access port.
(g)Turn ON the motor of the 11C3414   borescope blending kit.
(h)Monitor the borescope image of the blending tip while putting the blending tip near the blade and/or blisk damaged area.
(i)Turn OFF the motor of the 11C3414   borescope blending kit and put the blending tip in the location of the damaged area to find the minimum blend area as follows:
1Use the blending tip to make a mark on the airfoil at the center of the maximum damaged length. Refer to Figure 227.
2Use the blending tip to make a mark on each side of the center mark at four (for blades) or at three (for blisk airfoils) times dimension A (the maximum depth of the damage). Refer to Figure 227 and as follows:
aThe distance between the two marks will be the minimum blend length of the repair.
CAUTION:
DO NOT OPERATE THE MOTOR DURING THIS OPERATION, IF YOU DO NOT KNOW THE NECESSARY BLENDING MOVEMENT. DAMAGE TO THE BLADES AND BLISKS CAN OCCUR.
(j)Move the blending tip to simulate the movement necessary to start the blend repair across the minimum blend repair length.
(k)Make sure to know the necessary movements of the blending tip and that the borescope view is in the center of the blend area and is clear before turning the motor ON.
(l)Carefully apply pressure to the damaged area and start to blend. Start with slow movements and apply only light pressure to the damaged area.
(m)When the blend movements become correct, increase the speed and pressure of the blending tip on the blade or blisk damaged.
(n)Make sure not to apply too much pressure, the drive belt will not turn the blending tip. Lift the tip a small distance from the damaged area to continue blending.
(o)Remove all sharp edges by blending onto the edge of the blade or blisk after the blend repair is completed. Refer to Figure 228.
NOTE:
This will keep the airfoil contour as near as possible to the initial contour for maximum airfoil efficiency.
(p)Turn the motor OFF.
(q)Put the borescope drive shaft head in the zero degree position and remove the blending tip from the borescope access port.
CAUTION:
REMOVE A BLENDING TOOL TIP WITH THE DRIVE SHAFT HEAD IN THE 90 DEGREE POSITION. IF THE TIP WITH THE DRIVE SHAFT HEAD IS INSTALLED IN ANY OTHER POSITION, THE DRIVE BELT WILL BECOME DISENGAGED AND DAMAGE TO THE PART CAN OCCUR.
(r)Put the borescope drive shaft head in the 90 degree position, loosen the lock screw, and remove the blending tip. Refer to Figure 226.
CAUTION:
INSTALL A BLENDING TOOL TIP WITH THE DRIVE SHAFT HEAD IN THE 90 DEGREE POSITION. IF THE TIP WITH THE DRIVE SHAFT HEAD IS INSTALLED IN ANY OTHER POSITION, THE DRIVE BELT WILL BECOME DISENGAGED AND DAMAGE TO THE PART CAN OCCUR.
(s)Put the borescope drive shaft head in the 90 degree position, install the polishing tip on the drive shaft head, and tighten the lock screw as follows. Refer to Figure 225 and Figure 226.
1Make sure that the tip turns in the CW direction.
NOTE:
During operation, a tip that turns in the CW direction will be tightened by the force of the operation.
(t)Put the borescope drive shaft head in the zero degree position.
(u)Put the borescope drive shaft head into the compressor through the correct borescope access port.
WARNING:
USE EYE PROTECTION WHEN YOU POLISH MATERIAL OR PARTS. THE PARTICLES CAN CAUSE AN INJURY TO YOUR EYES. USE IN A WELL-VENTILATED AREA.
(v)Turn ON the motor of the 11C3414   borescope blending kit and polish the surface of the repaired area with the polishing tip.
(w)Turn the motor OFF.
(x)Put the borescope drive shaft head in the zero degree position and remove the polishing tip from the borescope access port.
(8)Do a borescope inspection of the blade and/or blisk airfoil blended areas. Refer to Subtask 72-00-00-220-079 (paragraph 5.E.) thru Subtask 72-00-00-220-164 (paragraph 5.M.), Figure 224, and Figure 227. Blend must be viewed from both sides (convex and concave) of the blade/airfoil to make sure that the damage is completely removed.
(9)Turn the 11C3414   borescope blending kit to OFF after all the repairs are complete.
(10)Install the applicable borescope plugs. Refer to Subtask 72-00-00-450-002 (paragraph 4.I.).
(11)Remove the 11C3407   adapter from the engine. Refer to Subtask 72-00-00-090-008 (paragraph 4.H.).
(12)Do an inspection of the borescope plugs and the crank pad cover as follows:
(a)Make sure to install the borescope plugs and the crank pad cover correctly.
(b)Make sure that there are no remaining borescope electrical leads or video cables on the engine assembly.
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Figure 223   11C3414 Borescope Blending Kit
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Figure 224   (Sheet 1 ) Blend Repair Areas and Limits
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Figure 224   (Sheet 2 ) Blend Repair Areas and Limits
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Figure 224   (Sheet 3 ) Blend Repair Areas and Limits
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Figure 224   (Sheet 4 ) Blend Repair Areas and Limits
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Figure 225   (Sheet 1 ) Tool Tips for Borescope Blending Tool
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Figure 225   (Sheet 2 ) Tool Tips for Borescope Blending Tool
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Figure 225   (Sheet 3 ) Tool Tips for Borescope Blending Tool
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Figure 226   Borescope Blending Tool Tip Installation
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Figure 227   Minimum Blend Length of Repaired Area
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Figure 228   Blend Repair Profiles
7 . Blending Procedure for the LPT Stage 1, 2, 3, 4, 5, 6, and 7 Blades with the 11C3414 Borescope Blending Kit.
Subtask 72-00-00-350-012
* * * SB   72-0040
A.Blend the stages 1-7 blades as follows:
(1)Set-up the 11C3414   borescope blending kit and engine to do a borescope blend to the stages 1-7 LPT blades. Refer to Figure 223.
(a)The stage 7 blade trailing edge can be repaired thru the turbine rear frame flange.
(2)Install the 11C3407   adapter . Refer to Subtask 72-00-00-040-022 (paragraph 4.F) and Subtask 72-00-00-220-353 (paragraph 4.G.).
(3)Remove the applicable borescope plug from the low pressure turbine stator assembly. Refer to Figure 226.
(a)Put the tag on the borescope plug to identify its access port.
(4)Do a zero index of the LPT rotor. Refer to Subtask 72-00-00-220-353 (paragraph 4.G.).
(5)For blending limits refer to Subtask 72-00-00-220-322 (paragraph 5.T.) thru Subtask 72-00-00-220-584 (paragraph 5.AF.) and Figure 229.
(6)Find the dimensions of the necessary blend repair as follows:
CAUTION:
INSTALL A BLENDING TOOL TIP WITH THE DRIVE SHAFT HEAD IN A 90 DEGREE POSITION. IF THE TIP WITH THE DRIVE SHAFT HEAD IS INSTALLED IN ANY OTHER POSITION, THE DRIVE BELT WILL BECOME DISENGAGED AND DAMAGE TO THE PART CAN OCCUR.
(a)Put the drive shaft head in a 90 degree position, install the measuring grid tip, and tighten the lock screw. Refer to Figure 225 and Figure 226.
(b)Put the drive shaft head in a zero degree position.
(c)Put the borescope drive shaft head into the turbine through the applicable borescope access port.
(d)Turn ON the engine of the 11C3414   borescope blending kit.
(e)Monitor the borescope image of the measuring grid tip while moving the measuring grid tip from the zero degree to the 90 degree position.
(f)Monitor the borescope image of the measuring grid tip as follows:
1Put the measuring grid tip near each blade damaged area. Use the grid tip to find and record the dimensions of the damage as follows:
aThe maximum depth of the damaged area.
bThe maximum width of the damaged area.
cThe maximum length of the damaged area.
dThe location of the edges of the damaged area from the nearest edge of the airfoil.
(g)Find if a blend repair is permitted for each area on a blade as follows:
1Examine the blend repair limits for the stages 1-7 LPT blades. Refer to Subtask 72-00-00-220-322 (paragraph 5.T.) thru Subtask 72-00-00-220-584 (paragraph 5.AF.) and Figure 229.
2Do an inspection of the damaged airfoils to identify previous blends on the leading edge and the trailing edge.
3Compare the data of each damaged area to the blend repair limits.
4For each damaged area permitted to be repaired on a stage 1 thru 5 blade, calculate the minimum blend repair length as eight times dimension A (the maximum depth of the damage). For each damaged area permitted to be repaired on a stage 6 and 7 blade, calculate the minimum blend repair length as 10 times dimension A (the maximum depth of the damage).
aAdjust the damaged area to the center in the blend repair calculation. Refer to Figure 229.
5Put the borescope drive shaft head in a zero degree position and remove the borescope shaft from the access port.
CAUTION:
REMOVE A BLENDING TOOL TIP WITH THE DRIVE SHAFT HEAD IN A 90 DEGREE POSITION. IF THE TIP WITH THE DRIVE SHAFT HEAD IS INSTALLED IN ANY OTHER POSITION, THE DRIVE BELT WILL BECOME DISENGAGED AND DAMAGED TO THE PART CAN OCCUR.
6Put the borescope drive shaft head in a 90 degree position, loosen the lock screw, and remove the measuring grid tip. Refer to Figure 226.
(7)Blend each blade damaged area that is permitted to repair. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) and do as follows:
(a)Get the correct blending tip for the size and/or the shape of the blade damaged area. Refer to Figure 225.
CAUTION:
INSTALL A BLENDING TOOL TIP WITH THE DRIVE SHAFT HEAD IN A 90 DEGREE POSITION. IF THE TIP WITH THE DRIVE SHAFT HEAD IS INSTALLED IN ANY OTHER POSITION, THE DRIVE BELT WILL BECOME DISENGAGED AND DAMAGE TO THE PART CAN OCCUR.
(b)Put the borescope drive shaft head in a 90 degree position, install the blending tip and tighten the lock screw. Refer to Figure 225 and Figure 226.
(c)Put the blending tip in a 90 degree position, turn the blending tip until it points away from you and briefly operate the motor.
1Make sure that the blending tip turns in the clockwise (CW) direction.
NOTE:
During operation, a blending tip that turns in the CW direction will be tightened by the force of the operation.
2If the blending tip turns in the counterclockwise (CCW) direction, do a check of the drive belt for a twisted installation.
aIf the drive belt is twisted, correct the belt so that it is not twisted.
bIf the belt was twisted and the blending tip turned in the CCW direction, make sure that the blending tip is not loose or disconnected from the drive shaft head.
(d)Put the drive shaft head in a zero degree position.
(e)Put the borescope drive shaft head into the turbine through the correct borescope access port.
(f)Turn ON the motor of the 11C3414   borescope blending kit.
(g)Monitor the borescope image of the blending tip while putting the blending tip near the blade damaged area.
(h)Turn OFF the motor of the 11C3414   borescope blending kit and put the blending tip in the location of the damaged area to find the minimum blend area as follows:
1Use the blending tip to make a mark on the airfoil at the center of the maximum damaged length.
2Use the blending tip to make a mark on each side of the center mark at four times dimension A (the maximum depth of the damage) for stage 1 thru 5 blades, and five times dimension A for stage 6 and 7 blades.
CAUTION:
DO NOT OPERATE THE MOTOR DURING THIS OPERATION, IF YOU DO NOT KNOW THE NECESSARY BLENDING MOVEMENT. DAMAGE TO THE BLADES CAN OCCUR.
(i)Move the blending tip to simulate the movement necessary to start the blend repair across the minimum blend repair length.
(j)Make sure to know the necessary movements of the blending tip and that the borescope view is in the center of the blend area and is clear before turning the motor ON.
(k)Carefully apply pressure to the damaged area and start to blend. Start with slow movements and apply only light pressure to the damaged area.
(l)When the blend movements become correct, increase the speed and pressure of the blending tip on the damaged blade.
(m)Make sure not to apply too much pressure, the drive belt will not turn the blending tip. Lift the tip a small distance from the damaged area to continue blending.
(n)Remove all sharp edges by blending onto the edge of the blade after the blend repair is completed. Refer to Figure 228.
NOTE:
This will keep the airfoil contour as near as possible to the initial contour for maximum airfoil efficiency.
(o)Turn the motor OFF.
(p)Put the borescope drive shaft head in a zero degree position and remove the blending tip from the borescope access port.
CAUTION:
REMOVE A BLENDING TOOL TIP WITH THE DRIVE SHAFT HEAD IN A 90 DEGREE POSITION. IF THE TIP WITH THE DRIVE SHAFT HEAD IS INSTALLED IN ANY OTHER POSITION, THE DRIVE BELT WILL BECOME DISENGAGED AND DAMAGE TO THE PART CAN OCCUR.
(q)Put the borescope drive shaft head in a 90 degree position, loosen the lock screw, and remove the blending tip. Refer to Figure 226.
CAUTION:
INSTALL A BLENDING TOOL TIP WITH THE DRIVE SHAFT HEAD IN A 90 DEGREE POSITION. IF THE TIP WITH THE DRIVE SHAFT HEAD IS INSTALLED IN ANY OTHER POSITION, THE DRIVE BELT WILL BECOME DISENGAGED AND DAMAGE TO THE PART CAN OCCUR.
(r)Put the borescope drive shaft head in a 90 degree position, install the polishing tip on the drive shaft head, and tighten the lock screw. Refer to Figure 225, Figure 226, and do as follows:
1Make sure that the tip turns in the CW direction.
NOTE:
During operation, a tip that turns in the CW direction will be tightened by the force of the operation.
(s)Put the borescope drive shaft head in a zero degree position.
(t)Put the borescope drive shaft head into the turbine through the correct borescope access port.
WARNING:
USE EYE PROTECTION WHEN YOU POLISH MATERIAL OR PARTS. THE PARTICLES CAN CAUSE AN INJURY TO YOUR EYES. USE IN A WELL-VENTILATED AREA.
(u)Turn ON the motor of the 11C3414   borescope blending kit and polish the surface of the repaired area with the polishing tip.
(v)Turn the motor OFF.
(w)Put the borescope drive shaft head in a zero degree position and remove the polishing tip from the borescope access port.
(8)Do a borescope inspection of the blade blended areas. Refer to Subtask 72-00-00-220-322 (paragraph 5.T.) thru Subtask 72-00-00-220-584 (paragraph 5.AF.) and Figure 229.
(9)Turn the 11C3414   borescope blending kit to OFF after all the repairs are complete.
(10)Install the applicable borescope plugs. Refer to Subtask 72-00-00-450-002 (paragraph 4.I.).
(11)Remove the 11C3407   adapter from the engine. Refer to Subtask 72-00-00-090-008 (paragraph 4.H.).
(12)Do an inspection of the borescope plugs and the crank pad cover as follows:
(a)Make sure to install the borescope plugs and the crank pad cover correctly.
(b)Make sure that there are no remaining borescope electrical leads or video cables on the engine assembly.
* * * END SB   72-0040
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* * * SB   72-0040
Figure 229   (Sheet 1 ) Blend Repair Areas and Limits
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* * * SB   72-0040
Figure 229   (Sheet 2 ) Blend Repair Areas and Limits
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* * * SB   72-0040
Figure 229   (Sheet 3 ) Blend Repair Areas and Limits
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* * * SB   72-0040
Figure 229   (Sheet 4 ) Blend Repair Areas and Limits
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* * * SB   72-0040
Figure 229   (Sheet 5 ) Blend Repair Areas and Limits