1) Corrosion and stains are permitted if you can lightly polish the damaged area with a crocus cloth and remove the damage.
(d)
Do a pressure test on the tubes. 1) Pressurize the tubes to 1500 psi (10342.1 kPa). Refer to
the Standard Practices Manual.
2) If the tube has leaks, replace it.
S 216-059-N00
(7)
Examine each external tube of the air system.
(a)
Examine the tubes for nicks, worn areas, scratches, and pitting.
NOTE: Pitting is a concentration of corrosion at a location.
____
1) Damage that is no more than 0.003 inch (0.076 mm) in depth is permitted all along the tube length; this includes the tube bend area.
(b) Examine the tubes for dents.
1) Dents that are less than 0.250 inch (6.350 mm) from the ferrules are not permitted.
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No. 2 - Inlet, Exhaust, and Externals Inspection
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2) Tube dents without sharp edges are permitted if the inner diameter of the tube is decreased by less than 20 percent.
NOTE: To do this check, use a ball that has a diameter
____ that is 80 percent of the inner diameter of the tube. Try to put this ball through the tube. Tubes in which the ball gets caught are not permitted.
(c)
Examine the tubes for corrosion and stains.
1) Corrosion and stains are permitted if you can lightly polish the damaged area with a crocus cloth and remove the damage.
(d)
Do a pressure test of the tubes. 1) Pressurize the tubes to 200 psi (1379.0 kPa). Refer to the
Standard Practices Manual.
2) If the tube has leaks, replace it.
S 216-180-N00
(8)
Examine the variable vane arms.
(a)
Examine the Inlet Guide Vanes (IGV), and the 5th- thru 7th-stage vanes for correct installation, and for loose or disengaged vane arms. 1) If you find a loose vane arm, replace the synchronizing
unison ring for that stage. 2) If you find a disengaged vane arm (the rivet pin is missing), remove the engine (AMM 71-00-02/401).
NOTE: A disengaged vane arm is a loss of a rivet pin
____ attachment to the synchronizing unison ring, an incorrect assembly of the vane trunnion, or a separation from the vane trunnion. Refer to PW Alert SB A72-419.
a) Refer to the PWA Engine CIR Manual for the applicable inspections.
S 216-181-N00
(9)
Examine the VSV (variable stator vane) actuating system for continue-in-service limits for worn or loose areas.
(a)
If the damage you find is more than the continue-in-service limits, replace or repair the area in 250 hours or less.
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~............................................................................... | CONTINUE-IN-SERVICE LIMITS FOR THE VARIABLE STATOR VANE ACTUATING SYSTEM | ................................................................................. | Examine | Continue-in-Service Limits | ................................................................................. | Clevis Attachments: Examine the lever | | | set connecting rod to the VSV unison | Loose connections are not permitted. | | ring for IGV, 5th-, 6th- and 7th-| | | stages for loose connections. | | .................................................................................
| Upper Mounting Attachments of the | A Maximum play of 0.040 inch |
| Actuator Support Bracket: Examine | (1.016 mm) is permitted. |
| the attachments for radial play. | |
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