Inspection of the Front Blade Retaining Ring Assembly [IAE]

TASK 72-31-13-200-010-B
Inspection of the Front Blade Retaining Ring Assembly

1. Reason for the Job
This task gives the procedure for the inspection of the LP compressor front blade retaining ring assembly.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	ACCESS PLATFORM 1M(3 FT)
No specific	AR	MAT - WORK
No specific	AR	WARNING NOTICE(S)

B. Referenced Information

REFERENCE	DESIGNATION
TASK 72-31-13-300-010-B	Repair of the LP Compressor Front Blade Retaining Ring - VRS1810
TASK 72-31-13-300-012-A	Replace the Shank Nuts of the Front Blade Retaining Ring - VRS1175
LP Compressor Front Blade Retaining Ring

3. Job Set-up
Subtask 72-31-13-941-054-A ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) On the center pedestal, on the ENG panel 115VU:
(a) Put a WARNING NOTICE(S) to tell persons not to start the engine.
(2) Make sure that the engine 1(2) shutdown occurred not less than 5 minutes before you do this procedure.
(3) On the overhead maintenance panel 50VU:
(a) Make sure that the ON legend of the ENG/FADEC GND PWR/1(2) pushbutton switch is off.
(b) Put a WARNING NOTICE(S) to tell persons not to energize the FADEC 1(2).

Subtask 72-31-13-941-055-A ** ON A/C NOT FOR ALL

B. Put the ground support equipment in to position.
(1) Put the ACCESS PLATFORM 1M(3 FT) in position to give access to the engine.
(2) Put the MAT - WORK in the air intake cowl.

NOTE: Make sure that the red warning pennants of the workmat can be seen external of the aircraft.

NOTE: Make sure the workmat has sufficient dimensions to give full protection to the lower half of the intake cowl surface.

4. Procedure
Subtask 72-31-13-210-051-A ** ON A/C NOT FOR ALL

A. Examine the fan front blade retaining ring.

LP Compressor Front Blade Retaining Ring ** ON A/C NOT FOR ALL

(1) Examine the abutment face of the front blade retaining ring assembly for gall, at locations 1, 2, 3, 4 and 5.
(a) If it has any gall, repair it (Ref. AMM TASK 72-31-13-300-010).
(2) Examine the bolt holes of the front blade retaining ring assembly for burrs at locations 6, 7 and 13.
(a) If the edges are burred, repair it (Ref. AMM TASK 72-31-13-300-010).
(3) Examine the snap diameter of the front blade retaining ring assembly for scores at locations 8 and 9.
(a) If it has scores, repair it (Ref. AMM TASK 72-31-13-300-010).
(4) Examine the outside diameter of the front blade retaining ring assembly for nicks, scratches and dents at location 10.
(a) If it has nicks, scratches or dents, repair it (Ref. AMM TASK 72-31-13-300-010).
(5) Examine the pin holes of the front blade retaining ring assembly for scores and burrs, at locations 11 and 12.
(a) If they have scores, repair them (Ref. AMM TASK 72-31-13-300-010).
(b) If they have burrs, repair them (Ref. AMM TASK 72-31-13-300-010).
(6) Examine the shank nuts of the front blade retaining ring assembly for damage at location 14.
(a) If they show signs of being loose or damaged, repair them (Ref. AMM TASK 72-31-13-300-012).
(b) If the locking torque is greater than 60 lbf.in (0.68 m.daN) or less than 6.5 lbf.in (0.07 m.daN), repair them (Ref. AMM TASK 72-31-13-300-012).
(7) Examine the spacers of the front blade retaining ring assembly for damage at location 15.
(a) If they are loose or missing, reject the ring.
(8) Examine the front blade retaining ring for arc-burns.

NOTE: An arc-burn is evident by a small circular or semi-circular heat-affected area on the front blade retaining ring surface that can contain pitting, melting or cracking. Visually a dark blue oxide discoloration can be associated with the heat-affected area.

(a) If it shows signs of arc-burns on the surface, reject them.

5. Close-up
Subtask 72-31-13-942-053-A ** ON A/C NOT FOR ALL

A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Remove the workmat from the air intake cowl.
(3) Remove the access platform(s).
(4) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 13:00:59 UTC