FAG tapered roller bearings comprise solid inner and outer rings with tapered raceways and tapered rollers in a window cage.
The classification and designation of tapered roller bearings in metric sizes is based on: DIN 720:2008; ISO 355:2007; ANSI/ABMA 19.1:2011 (prefix KJ)
The classification and designation of tapered roller bearings in inch sizes is based on: ANSI/ABMA 19.2:2013 (prefix K).
FAG tapered roller bearings in matched pairs are of an open design and are not self-retaining. As a result, the inner ring with the rollers and the cage can be mounted separately from the outer ring. Tapered roller bearings in matched pairs are also available in the X-life design.
Metric and inch size FAG bearings are available. Furthermore, tapered roller bearings are also available by agreement in many other designs and sizes as well as for special applications.
Radial and axial load carrying capacity
Single row tapered roller bearings can support axial forces in one direction and high radial forces. If the load carrying capacity of one bearing is not sufficient or the shaft is to be guided with a certain axial clearance in both directions, ready-to-fit matched bearing sets are available.
In principle, there are three arrangements of matched FAG tapered roller bearings, namely the X, O and tandem arrangement.
Contact angle
The contact lines extending from the outer ring at less than 90° form a cone that determines the arrangement of the bearing sets, Figure 1. The contact lines of the rolling element forces intersect at the contact cone apexes, so the spacing between the contact cone apexes of two tapered roller bearings is the support base of the bearing arrangement.
Figure 1: Arrangement of tapered roller bearings
1, X arrangement
2, O arrangement
3, Tandem arrangement
4, Gauge ring
In the case of matched pairs of bearings, two identical bearings are matched by means of an intermediate ring to form bearing sets.
X arrangement
In the case of bearing sets in an X arrangement, the contact lines converge relative to the bearing axis, Figure 1. While axial forces can be supported from both directions, this is only ever by means of one bearing. The construction of the X arrangement is simple and is the most frequently used arrangement of tapered roller bearings in a matched pair.
O arrangement
In the case of bearing sets in an O arrangement, the contact lines diverge relative to the bearing axis, Figure 1. While axial forces can be supported from both directions, this is only ever by means of one bearing. The support base of the O arrangement is at its largest, which is beneficial if the component with small bearing spacing must be guided with the smallest possible tilting clearance or tilting forces must be supported. Bearing arrangements in an O arrangement are relatively rigid and can also support loads resulting from tilting moments.
Tandem arrangement
In the case of bearing sets of a tandem arrangement, the contact lines run parallel to each other. In contrast to an X and O arrangement, the tandem arrangement can only support axial forces in one direction. In general, this bearing pair is adjusted against another tapered roller bearing, which supports axial forces in the opposite direction.