TM 5-3810-300-24 & P2
H.
While in press under pressure, check bearing
preload torque. Wrap soft wire around cage and
pull on horizontal line with pound scale. If a press
is not available, the pinion nut may be tightened to
the correct torque and preload checked.
The correct pressures and torque for checking
pressure bearing preload are as follows:
NUT TORQUE
NUT TORQUE
REQUIRED (FOR
REQUIRED (FOR
FASTENERS NOT
PRESSURE
FASTENERS USING
USING LOCKWIRE
PINION
REQUIRED
LOCKWIRE OR
OR COTTER PINS)
SHAFT
TO OBTAIN
COTTER PINS) TO
TO OBTAIN
THREAD
CORRECT
OBTAIN CORRECT
CORRECT
SIZE
PRE-LOAD
PRE-LOAD
PRE-LOAD
7/8"-20
6 tons
175- 200 lb. ft.
200- 275 lb. ft.
7/8"-20
6 tons
200- 275 lb. ft.
---------
(elastic stop nut)
1" -20
6 tons
300- 400 lb.
ft.
300- 400 lb. ft.
1 1/4"-18
11 tons
700- 900 lb.
ft.
700- 900 lb. ft.
1 1/2"-12
14 tons
800-1100 lb.
ft.
1 1/2"-18
14 tons
800-1100 lb.
ft.
800-1100 lb. ft.
1 3/4"-12
14 tons
800-1100 lb.
ft
900-1200 lb. ft.
2" -12
14 tons
1000-1300 lb. ft.
Use rotating torque, not starting torque.
If rotating torque is not within 5 to 15 pound inches, use thinner spacer to increase or thicker spacer to decrease preload.
NOTE
ASSUMING PINION CAGE DIAMETER TO BE 6 INCHES, THE RADIUS WOULD BE 3 INCHES AND
WITH 5 POUNDS PULL WOULD EQUAL 15 POUND INCHES PRELOAD TORQUE.
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