(b)
Make sure the actuator for the push-pull cam is extended and that the cam rollers touch the cam.
(c)
Hold the control switches in the open position for 5 to 10 seconds and release them.
(d)
Open this circuit breaker and attach the DO-NOT-CLOSE tag:
1) On the Nose Cargo Door Power panel H122: a) PULL UP CAM
(e)
Hold the control switches in the closed position until the drive unit motor stops.
CAUTION: DO NOT OPERATE THE NOSE CARGO DOOR BEFORE THE LINEAR
_______ ACTUATORS ARE ADJUSTED. THE DRIVE SYSTEM CAN BE DAMAGED IF YOU OPERATE THE DOOR BEFORE THE LINEAR ACTUATORS ARE ADJUSTED.
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(f)
Manually adjust the length of the linear actuators until rig pin ND-2 fits freely in the rig pin hole in the aft end of the actuator shafts (AMM 52-31-00/501).
(g)
Connect the flexible drive shafts on the linear actuators.
(h)
Remove the DO-NOT-CLOSE tags and close this circuit breaker:
1) On the Nose Cargo Door Power panel H122: a) PULL UP CAM
(i)
Hold the control switches to fully close the nose cargo door.
S 412-036
(5)
If the drive system is not operational, do these steps to close the door:
(a)
Use a 3/8-inch drive speed handle in the manual drive of the actuator on the push-pull cam to close the door.
NOTE: Approximately 200 turns of the speed handle are
____
necessary to close the door.
CAUTION: DO NOT EXCEED 8 POUND-FEET OF TORQUE WHEN YOU TURN THE LATCH ACTUATOR. YOU CAN DAMAGE THE LATCH ACTUATOR IF YOU EXCEED 8 POUND-FEET.
(b) Use a speed handle in each of the 16 latch actuators and turn them to the latched position (approximately 150 turns).
CAUTION: DO NOT OPERATE THE DOOR BEFORE THE LINEAR ACTUATORS ARE
_______ ADJUSTED. THE DRIVE SYSTEM CAN BE DAMAGED IF YOU OPERATE THE DOOR BEFORE THE LINEAR ACTUATORS ARE ADJUSTED.
(c) At the first opportunity, rig the linear actuators and the drive system as follows: 1) Close these circuit breakers:
a) ON THE P715 PANEL; NOSE CARGO DOOR (115V AC) b) ON THE P415 PANEL; NOSE CARGO DOOR CONT (28V DC)
c) ON THE H122 PANEL;
LATCHES 1-4 LEFT
LATCHES 1-4 RIGHT
LATCHES 5-8 LEFT
LATCHES 5-8 RIGHT
PULL UP CAM
DOOR LIFT
2) Hold the door control switches in the open position to move the actuator for the push-pull cam until the cam rollers touch the cam.
3) Hold the door control switches for 5 to 10 more seconds. 4) Open this circuit breaker on the H122 panel: a) PULL UP CAM
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5) Hold the door control switches in the closed position until the motor for the drive system stops.
6) Manually adjust the length of the linear actuators until rig pin ND-2 fits freely in the rig pin hole in the aft end of the actuator shafts (AMM 52-31-00/501).
7) Connect the flexible drive shafts to the linear actuators. 8) Close this circuit breaker on the H122 panel: a) PULL UP CAM 9) Hold the control switches to fully close the door.
G. Put the Airplane Back To Its Ususal Condition.
S 212-016
(1)
Make sure the door is fully closed, latched and locked.
S 082-017
(2)
Remove the electrical power, if it is not necessary.
S 092-018
(3)
Remove the safety barrier across the door opening.
TASK 52-31-00-912-019
4. Nose Cargo Door Opening with Totally Inoperative Latch Actuator
_______________________________________________________________
A. General
(1)
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本文链接地址：747-400 AMM 飞机维护手册 舱门 DOORS 2(5)
