* * * FOR ALL
TASK 72-31-43-200-801
1 . General.
A.This procedure gives instructions to do an inspection of the HPC rotor stage 3-4 spool (spool):
•
(01-730 , 72-31-00) (SIN 050B4)
•
(01-731 , 72-31-00) (SIN 050B4) (SB 72-0051)
•
(02-730 , 72-31-00) (SIN 050B4) (SB 72-0157 ).
(1)Give particular attention to the critical areas as follows:
•
Disk bores
•
Dovetail slots
•
Boltholes
•
Flange scallops
•
Fillets
•
Retainer hooks.
2 . Tools, Equipment, and Materials.
NOTE:
You can use equivalent alternatives for tools, equipment, and consumable materials.
A.Tools and Equipment.
(1)Special Tools. None.
(2)Standard Tools and Equipment. None.
(3)Locally Manufactured Tools. None.
B.Consumable Materials.
 
Code No.
Description
 
C05-003
Marking Pen (Pen)
C.Referenced Procedures.
 
ATA No.
Description
 
70-32-02
Fluorescent Penetrant Inspection
 
70-33-03
Special Inspection For Surface Fretting Or Galling
 
70-42-00
Blending And Removal Of High Metal Procedures
 
70-42-01
Polishing Bolt Hole Surfaces
 
72-31-43
Cleaning 001
 
72-31-43
Repair 003
D.Expendable Parts. None.
3 . Specific Inspection Procedure.
NOTE:
Any findings beyond manual limits that may be indicative of a possible crack and/or metallurgical defect must be reported to GE through a myGEAviation Technical Inquiry.
Subtask 72-31-43-230-001
A.Do a Class G fluorescent penetrant inspection of the stage 3-4 spool as follows. Use a non aqueous wet developer. Refer to TASK 70-32-02-230-001 (FLUORESCENT PENETRANT INSPECTION).
(1)Give particular attention to the critical areas as follows:
•
Disk bores
•
Dovetail slots
•
Boltholes
•
Flange scallops
•
Fillets
•
Retainer hooks.
(2)Remove the aluminum dioxide coating from the seal teeth. Refer to TASK 72-31-43-300-801 (72-31-43, REPAIR 003).
(3)Do not mask the spool.
(4)Indications 0.015 inch (0.38 mm) or less are permitted.
B.If the fluorescent penetrant inspection of the retainer hooks show indications that are more than 0.015 inch (0.38 mm), as specified in Subtask 72-31-43-230-001 (paragraph 3.A.), refer to Subtask 72-31-43-220-079 (paragraph 4.G.(6))/Subtask 72-31-43-220-080 (paragraph 4.G.(7)).
4 . Visual Inspection.
Refer to Figure 801.
Subtask 72-31-43-220-001
A.Do an inspection of all surfaces (does not include seal teeth) for:
(1)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the spool.
* * * FOR ALL
Figure 801   (Sheet 1 ) Inspection Areas for the Spool
* * * FOR ALL
Figure 801   (Sheet 2 ) Inspection Areas for the Spool
* * * FOR ALL
Figure 801   (Sheet 3 ) Inspection Areas for the Spool
Subtask 72-31-43-220-002
B.Do an inspection of all mating surfaces for:
(1)Pick-up and high metal:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the spool.
Subtask 72-31-43-220-003
C.Do an inspection of the flange surfaces for:
(1)Nicks, dents, and scratches on the forward flange forward face:
Maximum serviceable limit:
Any amount, 0.001 inch (0.02 mm) in depth, after the removal of high metal. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) .
Repair method:
Repair. Refer to TASK 72-31-43-300-802 (72-31-43, REPAIR 001).
Subtask 72-31-43-220-004
(2)Fretting, galling, and wear:
Maximum serviceable limit:
Any amount if in limits of TASK 70-33-03-220-006 (SPECIAL INSPECTION FOR SURFACE FRETTING OR GALLING) .
Repair method:
Replace the spool.
Subtask 72-31-43-220-053
(3)Nicks, dents, and scratches on the aft flange forward and aft face, and forward flange aft face:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth, after the removal of high metal. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) .
Repair method:
Repair. Refer to TASK 72-31-43-300-802 (72-31-43, REPAIR 001).
Subtask 72-31-43-220-005
D.Do an inspection of the outer diameter surfaces for:
(1)Nicks, dents, and scratches:
Maximum serviceable limit:
Any amount, 0.002 inch (0.05 mm) in depth after the removal of high metal. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) .
Repair method:
Repair. Refer to TASK 72-31-43-300-802 (72-31-43, REPAIR 001).
Subtask 72-31-43-220-006
E.Do an inspection of the forward and aft faces of dovetails for:
(1)Circumferential wear on the aft face of the stage 3 dovetails:
Maximum serviceable limit:
Any amount, 0.006 inch (0.15 mm) in depth.
Repair method:
Repair. Refer to TASK 72-31-43-300-805 (72-31-43, REPAIR 005).
Subtask 72-31-43-220-077
(2)Circumferential wear on the aft face of the stage 4 dovetails:
Maximum serviceable limit:
Any amount, 0.006 inch (0.15 mm) in depth.
Repair method:
Repair. Refer to TASK 72-31-43-300-805 (72-31-43, REPAIR 005) .
Subtask 72-31-43-220-078
(3)Nicks, dents, and scratches:
Maximum serviceable limit:
Not serviceable.
Repair method:
Repair. Refer to TASK 72-31-43-300-802 (72-31-43, REPAIR 001).
Subtask 72-31-43-220-081
(4)Discoloration (Refer to Figure 802):
Maximum serviceable limit:
Any amount, if the discoloration is uniform and does not show local variation.
Repair method:
Replace the spool.
Subtask 72-31-43-220-008
F.Do an inspection of the rabbets (diameter R and diameter B) for:
(1)Nicks, dents, and scratches:
Maximum serviceable limit:
Any amount, 0.003 inch (0.08 mm) in depth, any length, after removal of high metal. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) .
Repair method:
Repair. Refer to TASK 72-31-43-300-803 (72-31-43, REPAIR 002).
Subtask 72-31-43-220-009
(2)Fretting:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth, and in the limits of TASK 70-33-03-220-006 (SPECIAL INSPECTION FOR SURFACE FRETTING OR GALLING) and if in the serviceable limits of Subtask 72-31-43-220-028 (paragraph 6.D.(1)) thru Subtask 72-31-43-220-029 (paragraph 6.D.(2)) .
Repair method:
Repair. Refer to TASK 72-31-43-300-803 (72-31-43, REPAIR 002).
Subtask 72-31-43-220-010
G.Do an inspection of the retainer hooks for:
(1)Cracks or tears at the corners:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the spool.
Subtask 72-31-43-220-054
(2)Nicks, dents, and scratches of the retainer hooks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the spool.
Subtask 72-31-43-220-011
(3)Fretting or wear of the forward retainer hooks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Repair. Refer to TASK 72-31-43-300-802 (72-31-43, REPAIR 001).
Subtask 72-31-43-220-055
(4)Fretting or wear of the aft retainer hook ID:
Maximum serviceable limit:
Any amount, 0.005 inch (0.127 mm) in depth, after the removal of high metal. Blend any material that is projected above the fretted surface on the entire aft retainer hook ID. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) . Put a "F" mark on the top of the dove tail post where the fretting or wear is found. Use an approved C05-003  pen or an equivalent. Refer to TASK 70-16-02-350-017 (TEMPORARY MARKING) .
Repair method:
Replace the spool.
Subtask 72-31-43-220-056
(5)Galling:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the spool.
Subtask 72-31-43-220-079
(6)Cracks or indications more than 0.015 inch (0.38 mm) on the stage 3 aft face:
Maximum serviceable limit:
Not serviceable.
Repair method:
Repair. Refer to TASK 72-31-43-300-806 (72-31-43, REPAIR 006) .
Subtask 72-31-43-220-080
(7)Cracks or indications more than 0.015 inch (0.38 mm) on the stage 4 aft face:
Maximum serviceable limit:
Not serviceable.
Repair method:
Repair. Refer to TASK 72-31-43-300-806 (72-31-43, REPAIR 006) .
Subtask 72-31-43-220-082
(8)Discoloration (Refer to Figure 802):
Maximum serviceable limit:
Any amount, if the discoloration is uniform and does not show local variation.
Repair method:
Replace the spool.
Subtask 72-31-43-220-012
H.Do an inspection of the seal teeth for:
(1)Chipped or missing coating on lateral faces of diameter SS and diameter TT after recoat:
Maximum serviceable limit:
Any amount, 0.30 inch (7.6 mm) in length, if separated by a minimum of 0.050 inch (1.27 mm). Total collected length of missing coating on each seal tooth cannot be more than 3.0 inches (76 mm). Discoloration of the parent metal is not permitted.
Repair method:
Repair. Refer to TASK 72-31-43-300-801 (72-31-43, REPAIR 003).
Subtask 72-31-43-220-013
(2)Missing coating on the seal tip of diameter SS and diameter TT:
Maximum serviceable limit:
Any amount, 0.30 inch (7.6 mm) in length, if separated by a minimum of 0.050 inch (1.27 mm). Total collected length of missing coating on each seal tooth cannot be more than 3.0 inches (76 mm). Discoloration of the parent metal is not permitted.
Repair method:
Repair. Refer to TASK 72-31-43-300-801 (72-31-43, REPAIR 003).
Subtask 72-31-43-220-014
(3)Cracks:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the spool.
Subtask 72-31-43-220-015
(4)Nicks, dents, and scratches of stage 2 seal tip:
Maximum serviceable limit:
0.003 inch (0.07 mm) in depth, after the removal of high metal. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) .
Repair method:
Repair. Refer to TASK 72-31-43-300-802 (72-31-43, REPAIR 001).
Subtask 72-31-43-220-016
(5)Seal tip wear:
Maximum serviceable limit:
Any amount if in diameter limits of Subtask 72-31-43-220-031 (paragraph 6.E.). Discoloration of parent metal is not permitted.
Maximum repairable limit:
Not repairable.
Repair method:
Replace the spool.
Subtask 72-31-43-220-017
(6)Seal face wear:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the spool.
Subtask 72-31-43-220-057
(7)Nicks, dents, and scratches of stage 3 and stage 4 seal tip:
Maximum serviceable limit:
0.003 inch (0.07 mm) in depth, after the removal of high metal. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) .
Repair method:
Repair. Refer to TASK 72-31-43-300-802 (72-31-43, REPAIR 001).
Subtask 72-31-43-220-058
(8)Nicks, dents, and scratches of stage 3 and stage 4 seal teeth fillets:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the spool.
Subtask 72-31-43-220-018
I.Do an inspection of the dovetail for:
(1)Nicks, dents, and scratches on the pressure face:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth, after the removal of high metal on the pressure face.
Repair method:
Replace the spool.
Subtask 72-31-43-220-020
(2)Uniform wear on the concave and convex sides of stages 3-4:
Maximum serviceable limit:
Any amount, 0.003 inch (0.08 mm) in depth, if there is not a rough change in the profile. None permitted in the fillet.
Repair method:
Replace the spool.
Subtask 72-31-43-220-059
(3)Nicks, dents, and scratches on the top fillets:
Maximum serviceable limit:
Not serviceable.
Repair method:
Repair. Refer to TASK 72-31-43-300-802 (72-31-43, REPAIR 001).
Subtask 72-31-43-220-060
(4)Nicks, dents, and scratches on the bottom fillets:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the spool.
Subtask 72-31-43-220-076
(5)Constant fretting wear on the pressure faces of stages 3-4.
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth, if there is not a rough change in the contour. None permitted in the fillet.
Repair Method:
Repair. Refer to TASK 72-31-43-300-804 (72-31-43, REPAIR 004) .
Subtask 72-31-43-220-083
(6)Discoloration on the dovetail, including outer diameter and slot surfaces (Refer to Figure 802):
Maximum serviceable limit:
Any amount, if the discoloration is uniform and does not show local variation.
Repair method:
Replace the spool.
Subtask 72-31-43-220-021
J.Do an inspection of the boltholes for:
(1)Nicks, dents, and scratches on the inside diameter:
Maximum serviceable limit:
Any amount, 0.001 inch (0.02 mm) in depth 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 spool
Subtask 72-31-43-220-044
K.Do an inspection of diameter E for:
(1)Nicks and scratches:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth after removal of high metal. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) .
Repair method:
Repair. Refer to TASK 72-31-43-300-802 (72-31-43, REPAIR 001).
Subtask 72-31-43-220-046
(2)Dents:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth after removal of high metal. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) .
Repair method:
Repair. Refer to TASK 72-31-43-300-802 (72-31-43, REPAIR 001).
Subtask 72-31-43-220-045
L.Do an inspection of diameter F for:
(1)Nicks and scratches:
Maximum serviceable limit:
Any amount, 0.003 inch (0.07 mm) in depth after removal of high metal. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) .
Repair method:
Repair. Refer to TASK 72-31-43-300-802 (72-31-43, REPAIR 001).
Subtask 72-31-43-220-047
(2)Dents:
Maximum serviceable limit:
Any amount, 0.005 inch (0.12 mm) in depth after removal of high metal. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) .
Repair method:
Repair. Refer to TASK 72-31-43-300-802 (72-31-43, REPAIR 001).
Subtask 72-31-43-220-061
M.Do an inspection of the web-rim fillets:
(1)Nicks, dents, and scratches on stage 3 forward and stage 4 aft/forward web-rim fillets:
Maximum serviceable limit:
Not serviceable.
Repair method:
Repair. Refer to TASK 72-31-43-300-802 (72-31-43, REPAIR 001).
Subtask 72-31-43-220-062
(2)Nicks, dents, and scratches on stage 3 aft web-rim fillet:
Maximum serviceable limit:
Not serviceable.
Repair method:
Repair. Refer to TASK 72-31-43-300-802 (72-31-43, REPAIR 001).
Subtask 72-31-43-220-063
N.Do an inspection of flange scallops:
(1)Nicks, dents, and scratches on stage 3 flange scallop:
Maximum serviceable limit:
Any amount, 0.001 inch (0.02 mm) in depth after the removal of high metal. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) .
Repair method:
Repair. Refer to TASK 72-31-43-300-802 (72-31-43, REPAIR 001).
Subtask 72-31-43-220-064
(2)Nicks, dents, and scratches on stage 4 flange scallop:
Maximum serviceable limit:
Any amount, 0.001 inch (0.02 mm) in depth after the removal of high metal. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) .
Repair method:
Repair. Refer to TASK 72-31-43-300-802 (72-31-43, REPAIR 001).
Subtask 72-31-43-220-065
O.Do an inspection of surface K and surface T. Refer to Figure 801 and do as follows:
(1)Nicks, dents, and scratches:
Maximum serviceable limit:
Not serviceable.
Repair method:
Replace the spool.
Subtask 72-31-43-220-066
P.Do an inspection of the disk bores and bore faces:
(1)Nicks and dents:
Maximum serviceable limit:
Any amount, 0.001 inch (0.02 mm) in depth after removal of high metal. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) .
Repair method:
Repair. Refer to TASK 72-31-43-300-802 (72-31-43, REPAIR 001).
Subtask 72-31-43-220-067
(2)Scratches:
Maximum serviceable limit:
Not serviceable.
Repair method:
Repair. Refer to TASK 72-31-43-300-802 (72-31-43, REPAIR 001).
Subtask 72-31-43-220-024
Q.Do an inspection of all other surfaces for:
(1)Nicks and dents:
Maximum serviceable limit:
Any amount, 0.001 inch (0.02 mm) in depth after removal of high metal. Refer to TASK 70-42-00-350-002 (BLENDING AND REMOVAL OF HIGH METAL PROCEDURES) .
Repair method:
Repair. Refer to TASK 72-31-43-300-802 (72-31-43, REPAIR 001).
Subtask 72-31-43-220-068
(2)Scratches:
Maximum serviceable limit:
Not serviceable.
Repair method:
Repair. Refer to TASK 72-31-43-300-802 (72-31-43, REPAIR 001).
5 . Application of Coatings
Subtask 72-31-43-200-001
A.Apply coating to the spool. Repair. Refer to TASK 72-31-43-300-801 (72-31-43, REPAIR 003).
6 . Special Dimensional Inspection.
Refer to Figure 801.
NOTE:
Do a dimensional inspection only if a visual inspection shows or other defect conditions are found that make a dimensional inspection necessary.
Subtask 72-31-43-220-025
A.Make a reference axis with diameter R and surface P.
Subtask 72-31-43-220-026
B.Measure the runout of the seal teeth diameters in relation to diameter R and surface P. The runout must not be more than 0.005 inch (0.13 mm) FIR.
Subtask 72-31-43-220-027
C.Measure each diameter at eight equally spaced locations. Calculate the average diameter dimension. Compare the average diameter to the dimensions given in the dimensional inspection.
Subtask 72-31-43-220-028
D.Measure the diameters as follows:
(1)Diameter R:
Minimum serviceable limit:
15.4100 inches (391.414 mm).
Maximum serviceable limit:
15.4140 inches (391.516 mm).
Repair method:
Repair. Refer to TASK 72-31-43-300-803 (72-31-43, REPAIR 002).
Subtask 72-31-43-220-029
(2)Diameter B:
Minimum serviceable limit:
21.0400 inches (534.416 mm).
Maximum serviceable limit:
21.0440 inches (534.517 mm).
Repair method:
Repair. Refer to TASK 72-31-43-300-803 (72-31-43, REPAIR 002).
Subtask 72-31-43-220-030
(3)Runout of diameter B in relation to diameter R and surface P:
Maximum serviceable limit:
0.0020 inch (0.051 mm).
Repair method:
Repair. Refer to TASK 72-31-43-300-803 (72-31-43, REPAIR 002).
Subtask 72-31-43-220-031
E.Measure the interstage air seal teeth diameters for:
(1)Diameter PP:
Minimum serviceable limit:
17.631 inches (447.83 mm).
Maximum serviceable limit:
17.641 inches (448.08 mm).
Repair method:
Replace the spool.
Subtask 72-31-43-220-032
(2)Diameter QQ:
Minimum serviceable limit:
18.143 inches (460.83 mm).
Maximum serviceable limit:
18.153 inches (461.09 mm).
Repair method:
Replace the spool.
Subtask 72-31-43-220-033
(3)Diameter RR:
Minimum serviceable limit:
18.655 inches (473.84 mm).
Maximum serviceable limit:
18.665 inches (474.09 mm).
Repair method:
Replace the spool.
Subtask 72-31-43-220-034
(4)Diameter SS:
NOTE:
Seal teeth dimensions apply before the coating is re-applied.
Minimum serviceable limit:
20.023 inches (508.59 mm).
Maximum serviceable limit:
20.045 inches (509.14 mm).
Repair method:
Repair. Refer to TASK 72-31-43-300-801 (72-31-43, REPAIR 003).
Subtask 72-31-43-220-035
(5)Diameter TT:
NOTE:
Seal teeth dimensions apply before the coating is re-applied.
Minimum serviceable limit:
21.197 inches (538.41 mm).
Maximum serviceable limit:
21.219 inches (538.96 mm).
Repair method:
Repair. Refer to TASK 72-31-43-300-801 (72-31-43, REPAIR 003).
* * * FOR ALL
Figure 802   Examples of Acceptable Discoloration on 3-4 Spool Dovetail Surfaces