747-400 AMM 飞机维护手册 滑油 OIL(81)

曝光台 注意防骗 网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者

 1)  If there are five or more chips on a MCD probe, remove the engine from operation and do an analysis of the contamination.
 (d)  Flakes have irregular shape, but are usually flat and shiny on the two sides.
 NOTE: You must do an analysis of the flakes to know their
____ source. The flakes come from ball bearings, roller bearings, and gearteeth. The flakes from the ball bearings and the roller bearings are usually between 0.002-0.010 inch (0.051-0.254 mm) in thickness. They usually have an irregular, plate-like shape and have radial cracks. When you clean the flakes, it is more shiny than other types of contamination. The flakes from the gearteeth are shiny, long, thin, and can have an irregular shape. They are usually thicker and not as shiny as the flakes from the ball or roller bearing.
 1)  If there are five or more flakes on a MCD probe, remove the engine from operation and do an analysis of the contamination.
 S 216-019-N00
 (2)  If the contamination found was build debris, you can continue the engine in operation but you must obey the usual inspection limits for the MCD probe.
 NOTE: The usual inspection limits are the limits that the operator
____
 has made for his permitted maintenance program.

 S 116-020-N00
 (3)  
If magnetic fines were found on more than 50 percent of the tip circumference of the MCD probe or there ae less than five chips or flakes on the MCD probe, do the steps that follow:

 (a)  
Remove the main oil filter (AMM 79-21-05/401).

 1)  Keep the oil which you drain from the housing of the main oil filter.

 (b)  
Flush the main oil filter with the petroleum solvent.

 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 79-21-10
 ALL  ú ú N01 Page 608 ú Oct 18/99
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
(c)  
Put the petroleum solvent through a filter paper or a clean cloth. 1) Keep the contamination for the correct identification.

 (d)  
Install the new main oil filter (AMM 79-21-05/401).

 (e)  
Examine the main oil filter and the oil in the housing for metallic contamination. 1) If there is metallic contamination which is not build

 debris, and the quantity is sufficient to make a circle which has a minimum diameter of 0.50 inch (12.700 mm), do the steps that follow: a) Remove the engine from operation. b) Disassemble the engine and find the source of the
 contamination.
 2)  If there is metallic contamination which is not build debris, and the quantity is not sufficient to make a circle which has a minimum diameter of 0.50 inch (12.700 mm), do the steps that follow: a) Continue the engine in operation but examine the MCD
 probe each 25 hours of operation for the subsequent 200
 hours. b) Collect the contamination from the MCD probe. c) Do an analysis of the material in the subsequent 200
 hours of operation.
 1.  If there is contamination from the bearings or gear
_ material, do the steps that follow:
 a.  Remove the engine from operation.
_
 b.  Disassemble the engine and find the source of
_ the contamination.
 2.  If you do not find bearing or gear material, and if the quantity of the contamination decreases in each inspection during the 200 hours, put the engine back into operation.
 TASK 79-21-10-206-021-N00
 4.  Do a Functional Inspection of the Magnetic Chip Detector Probe
______________________________________________________________
 A.  References
 (1)  
AMM 79-21-10/401, Magnetic Chip Detectors

 B.  
Do a Functional Inspection of the MCD Probe

 S 246-022-N00
 (1)  Do a check of the magnetic strength of the MCD Probe with one of the steps that follow:
 CAUTION: DO NOT LET THE MAGNETS ON THE MCD PROBE TOUCH EACH OTHER.
_______ IF THE MAGNETS TOUCH EACH OTHER, THEY WILL BECOME DEMAGNETIZED AND MUST BE REPLACED.
 (a)  
Hang the MCD probe from a flat, ferrous surface. 1) The MCD probe must hang from the metal surface.

 (b)  
Make sure the MCD probe can hold a steel ball bearing with a diameter of 0.750 inch (19.050 mm).

 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
　
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：747-400 AMM 飞机维护手册 滑油 OIL(81)