SKF - Rolling Bearings

Basic selection criteria
Axial displacement
Shafts, or other rotating machine com ponents,
are generally supported by a locating and
a non-locating bearing († Bearing systems,
page 160).
The bearing in the locating position must be
able to locate the shaft axially in both directions.
The most suitable bearings for the
locating position are those bearings that can
accommodate combined loads, or can provide
axial guidance in combination with a second
bearing.
Non-locating bearings must accommodate
axial movement of the shaft, to avoid induced
axial loads when, for example, thermal elong a­
tion of the shaft occurs. Bearings suitable for
the non-locating position include needle roller
bearings and NU and N design cylindrical roller
bearings († fig. 33). NJ design cylindrical
roller bearings and some full complement
design cylindrical roller bearings can also be
used.
In applications where the required axial displacement
is relatively large and misalignment
may also occur, a CARB toroidal roller bearing
is an excellent choice as the non-locating
bearing († fig. 34).
All of these bearings accommodate axial
displacement between the shaft and the housing,
within the bearing. Values for the permissible
axial displacement within the bearing are
listed in the relevant product tables.
If non-separable bearings, e.g. deep groove
ball bearings or spherical roller bearings
(† fig. 35) are used as non-locating bearings,
one of the bearing rings must have a loose fit
(† Radial location of bearings, page 165).
Fig. 33
Fig. 34
Fig. 35
A
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