D.  
Procedure

 S 216-003-N00
 (1)  Look forward through the turbine exhaust area and between 6th-stage LPT blades to see the 6th-stage LPT vanes.
 NOTE: You can only see one airfoil side, one shroud, and the
____
 leading edge of the vane.

 S 216-002-N00
 (2)  With a fluorescent light, examine the areas you can see of the vane trailing edge, shrouds, and airfoil for damage.
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 72-53-02
 ALL  ú ú N01 Page 601 ú Jun 18/00
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
////////////////////////A / PW4000 SERIES /747-400 / ENGINES /MAINTENANCE MANUAL ////////////////////////

L-A0609 6th-Stage LPT Vane Inspection Figure 601

EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 72-53-02
 ALL  ú ú N01 Page 602 ú Jun 10/88
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
S 226-004-N00
 (3)  If you can see damage on the vane, do a full inspection of the vane.
 NOTE: Do this with a borescope, mirrors, or other tools necessary
____
 to examine the leading edge.

 (a)  
Area A
 1) Damage or cracks are not permitted.

 (b)  
Area B 1) Nicks, which are not blend repaired, are permitted if they are no more than 0.015 inch (0.381 mm) in depth. 2) High metal, which is caused by nicks, is permitted if it is

 lifted no more than 0.030 inch (0.762 mm). 3) Cracks are not permitted.

 (c)  
Area C
 1) Damage or cracks are not permitted.

 (d)  
Area D 1) You can permit nicks and dents that are not blend repaired,

 if they are no more than 0.020 inch (0.508 mm) in depth. 2) Cracks are not permitted.
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 72-53-02
 ALL  ú ú N01 Page 603 ú Oct 18/99
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
6TH-STAGE LPT (OUTER) AIRSEALING RING SEGMENT - INSPECTION/CHECK
________________________________________________________________
 1.  General
_______
 A.  This procedure gives the steps for the inspection of the outer airsealing ring segment of the 6th-stage low pressure turbine (LPT). This outer airsealing ring segment of the 6th-stage LPT will be referred to as the outer airsealing ring segment.
 B.  This outer airsealing ring segment is made of abradable honeycomb and is aligned with the knife-edges of the 6th-stage LPT blades.
 C.  You can remove the turbine exhaust sleeve and plug to get access to the outer airsealing ring segment.
 TASK 72-53-03-206-001-N00
 2.  Examine 6th-Stage LPT (Outer) Airsealing Ring Segment (Fig. 601)
_____________________________________________________
 A.  References
 (1)  
AMM 78-11-02/401, Turbine Exhaust Plug

 B.  
Access

 (1)  
Location Zone
 412 Engine 1 - LPT
 422 Engine 2 - LPT
 432 Engine 3 - LPT
 442 Engine 4 - LPT

 C.  
Procedure

 S 016-002-N00
 (1)  
Remove the turbine exhaust plug (AMM 78-11-02/401).

 S 226-003-N00

 (2)
Inspect the Stage 6 LPT (Outer) Airsealing Ring Segment Assembly.

 (a)  
Damage that is next to the wear groove and is more than 3.0 inches (76.2 mm) in length in each segment, unlimited segments, is not permitted.

 NOTE: Look forward through the turbine exhaust case to examine
____ the Stage 6 LPT (Outer) Airsealing Ring Segment Assembly.
 An increase in segment damage will show a decrease in performance.
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
　
中國航空網(wǎng) m.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：747-400 AMM 飛機(jī)維護(hù)手冊(cè) 發(fā)動(dòng)機(jī) ENGINE 2(101)