Detailed Inspection of the Pack Downstream Check-Valve Flappers

TASK 21-52-00-200-013-A
Detailed Inspection of the Pack Downstream Check-Valve Flappers

FIN: 15HM
FIN: 16HM

1. Reason for the Job
Referenced from AMM
2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
TASK 21-52-43-000-001-A	Removal of the Pack Downstream Check-Valves
TASK 21-52-43-400-001-A	Installation of the Pack Downstream Check-Valves

3. Job Set-up
Subtask 21-52-00-010-072-A

A. Remove the pack downstream check-valves as necessary (Ref. AMM TASK 21-52-43-000-001).

4. Procedure
Subtask 21-52-00-210-061-A

A. Detailed Inspection of the Pack Downstream Check-Valve Flappers for Condition and Operation.
(1) Make sure that the check valve is clean.
(2) Do a detailed visual inspection for signs of cracks, dents, marks or corrosion of:

the valve flap and its seat,
the hinge pin and,
the spring of the valve flap.

(3) Move the valve flap with your hand to make sure that it operates smoothly on its hinge pin.
(4) Make sure that:

the valve flap touches its seat correctly and,
there are no gaps between the valve flap and the seat.

(5) If necessary replace the pack downstream check-valve.

5. Close-up
Subtask 21-52-00-410-070-A

A. Install the pack downstream check-valves as necessary (Ref. AMM TASK 21-52-43-400-001).

[Rev.10 from 2021] 2026.04.02 06:48:36 UTC