Bearings of the TDO configuration
Bearings of the TDO configuration have one double row outer ring, or cup, and two inner rings with roller and cage assembly, or cones (fig 1). Normally these bearings have an intermediate ring between the two cones. They are thus ready-to-mount units as adjustment of the axial clearance or preload has already been made at the production stage. In these bearings the cones are arranged back-to-back so that the load lines diverge towards the bearing axis. By virtue of this the bearings enable relatively stiff arrangements to be made which can accommodate considerable tilting moments.
These arrangements may be either locating or non-locating. For non-locating arrangements the axial displacement must take place between the outer ring and the housing bore. Those bearings having a blind hole or locating slots in the outer ring are particularly suitable for mounting with a loose fit in the housing as a cylindrical pin which engages the hole or slot can be used to prevent the outer ring from turning in its seat. To enable axial displacement of these bearings in the housing it is recommended that the pin should have a smaller diameter than the hole.
SKF double row tapered roller bearings of the TDO configuration are generally produced in the designs described in the following. Basically these designs differ in cage design or whether provision is made for relubrication or an intermediate ring is positioned between the inner rings.