(b)
With the handle of the torque wrench parallel to the surface of the pressure relief vent, turn the handle down smoothly.
(c)
As you turn the handle down, make a record of the torque when the latch on the pressure relief vent opens.
(d)
The latch is serviceable if the torque used to open it is 100-130 pound-inches (11.3-14.7 newton-meters).
NOTE: The force necessary to open the latch is 50-65 pounds.
____ (22.7-29.5 kilograms) But, the arm of the pivot support assembly which pulls up on the latch decreases the applied force by a factor of two. This makes it necessary to increase the force you apply by a factor of two. Thus, the latch must unlock when the torque wrench shows 100-130 pound-inches (11.3-14.7 newton-meters).
S 025-017-N00
(6)
If the force to release the latch (1) is not in the specified limits, replace the latch.
S 085-018-N00
(7)
Remove the load-test-adapter-tool from the pressure relief vent.
(a)
Remove the pivot support assembly (5) from the pressure relief vent.
(b)
Remove the adapter assembly (2) from the pressure relief vent.
(c)
Install the mounting bolts, washers and nuts (3) on the latch, and tighten the nuts (3).
S 725-019-N00
(8)
Do these steps again to do a test of the other latch on the pressure relief vent.
S 415-020-N00
(9)
When you have completed the tests for the two latches on the pressure relief vent, do these steps:
(a)
Put the blade of a straight-slot screwdriver into the slot of one of the latches (1) on the pressure relief vent.
(b)
Move the screwdriver handle until the latch (1) is in the fully open position, and close the pressure relief vent.
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////////////////////////A / PW4000 SERIES /747-400 / ENGINES/MAINTENANCE MANUAL ////////////////////////
(c)
Move the screwdriver in the opposite direction to lock the latch (1).
(d)
Do these steps again to close the opposite latch (1) on the pressure relief vent.
TASK 71-11-03-825-006-N00
3. Aerodynamic Smoothness Adjustment for the Inlet Cowl Pressure Relief Vent
_________________________________________________________________________
A. Consumable Materials
(1)
C00259 Primer - BMS 10-11, Type 1
B.
Access
(1)
Location Zone
411 Engine 1 - Inlet Cowl
421 Engine 2 - Inlet Cowl
431 Engine 3 - Inlet Cowl
441 Engine 4 - Inlet Cowl
C.
Procedure (Fig. 502)
S 825-007-N00
(1) Examine the side clearance and smoothness of the pressure relief vent.
(a)
Make sure the vent left/right side clearance is 0.03-0.04 inch (0.8-1.0 mm). 1) If the clearance is not satisfactory, add or remove the
washers installed between the hinge assemblies and bushings.
(b)
Make sure the vent forward/aft side clearance is 0.03-0.04 inch (0.8-1.0 mm). 1) If the clearance is not satisfactory, do the steps that
follow: a) With a drift punch, remove the roll pins from the hinge assemblies. b) Loosen the bolts which attach the vent to the hinge assemblies. c) Adjust the vent until it is in the tolerances for the aerodynamic smoothness.
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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
1 Tighten the bolts.
_ d) Find the two spare holes in the hinge fitting opposite to the holes which were used for the roll pins. e) Drill the two spare holes on the opposite side of the bolts with a 1/8 inch (3.2 mm) diameter bit.
f) Use a drift punch to install the roll pins in the spare holes until they are smooth with the external surface of the vent.
(c) Make sure the vent is smooth with the outer surface of the inlet cowl [+0.025/-0.035 inch (+0.64/-0.89 mm)]. 1) If the vent is not smooth, do the steps that follow:
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本文链接地址：747-400 AMM 飞机维护手册 动力装置 POWER PLANT 2(68)
