SKF - Rolling Bearings

7 Tapered roller bearings
Designs and variants
Tapered roller bearings have tapered inner
and outer ring raceways and tapered rollers.
They are designed to accommodate combined
loads, i.e. simultaneously acting radial and
axial loads. The projection lines of the raceways
meet at a common point on the bearing
axis († fig. 1) to provide true rolling and low
friction. The axial load carrying capacity of
tapered roller bearings increases with
increasing contact angle a. The size of the
angle is related to the calculation factor e (†
product tables): the larger the value of e, the
larger the contact angle. A single row tapered
roller bearing is typically adjusted against a
second tapered roller bearing.
Single row tapered roller bearings are separ
able († fig. 2), i.e. the inner ring with roller
and cage assembly (cone) can be mounted
separately from the outer ring (cup).
The factors that influence SKF bearing performance
and service life include but are not
limited to the following:
More information
Bearing life and load ratings ...... 63
Design considerations ........... 159
Bearing systems ................. 160
Recommended fits ............... 169
Abutment and fillet dimensions ..... 208
Lubrication .................... 239
Mounting, dismounting and
bearing care ................... 271
Mounting instructions for individual
bearings .............† skf.com/mount
SKF bearing maintenance handbook
. . . . . . . . . . . . (ISBN 978-91-978966-4-1)
• roller end / flange contact area
The geometry and surface finish of the roller
ends and the area on the flange that makes
contact with the roller ends († fig. 3) have
been optimized to promote and maintain the
formation of a lubricant film. This reduces
friction and frictional heat as well as flange
wear. The bearings can better maintain
preload and run at reduced noise levels.
• raceway profiles
To extend service life under misalignment or
heavy load conditions, SKF tapered roller
bearings have either crowned raceways or a
logarithmic profile to prevent stress peaks
at the roller ends. The logarithmic profile is
designed to optimize load distribution along
the rollers.
• consistency of profiles and roller size
The rollers used in SKF tapered roller bearings
are made to such close tolerances that
they are virtually identical. These extremely
close tolerances, together with the precision
of the raceway profiles, provide optimal load
distribution over the rollers to reduce noise
and vibration levels and enable preload to
be set more accurately.
a
a
Fig. 1
798