An application incorporating a CARB® toroidal roller bearing provides the following:
The self-aligning capability of the bearing is particularly important in applications where there is misalignment as a result of manufacturing or mounting errors or shaft deflections. To compensate for these conditions, the bearing can accommodate misalignment up to 0.5 degrees between the bearing rings without any detrimental effects on the bearing or bearing service life
Previously, only cylindrical and needle roller bearings could accommodate thermal expansion of the shaft within the bearing. Now the toroidal roller bearing can be added to that list.
The inner and outer rings of the bearing can be displaced, with respect to each other, up to 10% of the bearing width. By installing the bearing so that one ring is initially displaced with respect to the other one, it is possible to extend the permissible axial displacement in one direction. In contrast to cylindrical and needle roller bearings that require accurate shaft alignment, this is not needed for toroidal roller bearings, which can also cope with shaft deflection under load. This provides a solution to many problem cases.
Long system life
The ability to accommodate misalignment plus axial displacement with virtually no friction enables this type of bearing to provide benefits to the bearing arrangement and its associated components
• Internal axial displacement is virtually without friction; there are no internally, induced axial forces, thus operating conditions are considerably improved.
• The non-locating bearing as well as the locating bearing only need to support external loads.
• The bearings run cooler, the lubricant lasts longer and maintenance intervals can be appreciably extended.
High load carrying capacity
It is claimed that this toroidal roller bearing can accommodate very high radial loads. This is due to the optimized design of the rings combined with the design and number of rollers. It is also claimed that the large number of long rollers make CARB® bearings the strongest of all aligning roller bearings.
Also, these bearings can cope with small deformations and machining errors of the bearing seating. The rings can accommodate these small imperfections without the danger of edge stresses. The high load carrying capacity plus the ability to compensate for small manufacturing or installation errors provide opportunities to increase machine productivity and uptime.
Increased performance or downsizing
For bearing arrangements incorporating this toroidal roller bearing as a non-locating bearing, internally-induced axial forces are prevented. Together with high load carrying capacity it is also claimed that:
• for the same bearing size in the arrangement, performance can be increased or the service life extended, or
• new machine designs can be made more compact to provide the same, or even higher performance.
Self-aligning ball or spherical roller bearings in the non-locating position need to be able to slide within the housing seating. This sliding, however, causes axial vibrations which can reduce bearing service life considerably. Bearing arrangements that use CARB® toroidal roller bearings as the non-locating bearing are stiff because the bearing can be radially and axially located in the housing and on the shaft. This is possible because thermal expansion of the shaft is accommodated within the bearing. The stiffness of the bearing arrangement, combined with the ability of the bearing to accommodate axial movement, substantially reduces vibrations within the application to increase service life of the bearing arrangement and related components.
Full dimensional interchangeability
C b a ‘f OPeratin9 hours
102 2 3 4 5 678910s 2 3 4 6 678910* 2
The boundary dimensions of these toroidal roller bearings are in accordance with ISO 15:1998. This provides dimensional interchangeability with self-aligning ball bearings, cylindrical roller and spherical roller bearings in the same dimension series. The range also covers wide bearings with low cross-sections normally associated with needle roller bearings.
 Kinematic similarity in which the dimension of time is added to length and all peripheral flow velocities at any point within a machine are in a constant ratio to the velocities at corresponding points of the similar unit.
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