Tapered roller bearings are designed so the tapered vertex of the raceway surfaces of the inner and outer rings and rollers converge at one point on the certerline of the bearing. Due to this design feature,rollers move along the center of theraceway surfaces. The tapered rollers are guided by the compound force of the inner and oter raceway surfaces which keep them pressed up against the large rib on the raceway surfaces which keep them pressed up against the large rib on the inner ring.A large variety of these bearings,including single,double,and four row arrangements,are in use both in  metric and inch series.