YORK INTERNATIONAL
48
at the factory. If it is necessary to purchase a bearing
locally, be sure it can be worked around in the housing
with a short shaft made of wood or other soft material
placed in the bearing.
Prior to installing the bearing on the shaft, it should be
worked around in the housing to make sure that self
alignment will be obtained where the bearing is installed.
After the shaft journal has been inspected for cleanli-
ness, metal chips or burrs, the bearing is slipped, not
forced, onto the shaft. Forcing the bearing onto the shaft
by the use of flange, pillow block, or outer ring will dam-
age the bearing internally. Force applied in this way
transmits the load to the inner race through the balls in
the bearing. Since the bearings are not designed for
axial loading, the sides of the races in which the balls
turn can be damaged. If the bearing cannot be made to
slip onto the shaft by pressing on the inner ring of the
bearing, check the shaft for burrs. Install the bearing so
the part of the inner race which receives the locking
collar or contains set screws is toward the outside of
the unit.
If the grease fitting must be changed on bearings which
utilize a locking pin under the fitting, it is important to
see that the locking pin is in place when the fitting is
replaced. If an adapter or grease fitting of improper
size and length is used, the locking pin may be either
too tight or loose and can affect the alignment and
relubrication of the bearing.
BEARING LOCKING DEVICES
Various types of locking devices are used to secure
bearing(s) to the fan shaft. Refer to the instructions
packed with bearings for special information. Figure 47
is a typical bearing with a setscrew type locking de-
vice. The various locking devices can be classified un-
der basic types: eccentric locking type, concentric lock-
ing type, and Skwezloc type.
Eccentric Type
An eccentric self-locking collar is turned and driven
with a punch in the direction of shaft rotation to lock
the bearing inner ring to the shaft. (See Figure 48)
When the eccentric collar is engaged to the cam on the
bearing inner ring and turned in direction of rotation, it
grips the shaft with a positive binding action. The collar
is then locked in place with the set screw provided in
the collar.
The self-locking collar is placed on the shaft with its
cam adjacent to the cam on the end of the bearing’s
wide inner ring. In this position, with collar and bearing
cams disengaged, the collar’s bore is concentric with
that of the bearing’s inner ring. The wide inner ring is
loose on the shaft. By turning the collar in the direction
of normal shaft rotation, the eccentric recessed cam
will drop over and engage with the corresponding cam
on the bearing inner, causing it to grip the shaft tightly
with a positive binding action. (See Figure 50) Make
sure the two cams engage smoothly and the locking
collar is down flat against the shoulder of the inner ring.
The wide inner ring is now locked to the shaft. Using a
punch or similar tool in the drilled hole of the collar, tap
the tool lightly to lock the collar in the direction of nor-
mal shaft rotation.
FIG. 47 –
BEARING WITH SETSCREW TYPE
LOCKING DEVICE
FIG. 48 –
BEARING WITH ECCENTRIC CAM
LD06357
00418VIP
Maintenance
