Roller bearing types

Tapered Rollers

Cylindrical Rollers

Needle Rollers

There are two styles of roller bearings: those with ¡°non-tapered¡± rollers (cylindrical and needle) and those with ¡°tapered¡± rollers.

The most apparent difference between the two types is the shape of the rollers and the curvature of the races. In a non-tapered roller bearing, the centers of each part run parallel to one another . In the tapered roller, if the imaginary lines were run through the outer race and inner race, they would taper off and eventually coincide at a point even on a line extended through the bearing¡¯s center .

Other differences between non-tapered and tapered rollers, such as operating conditions, load capacity and shaft direction, will be explained in this chapter. 

Tapered roller bearing

In profile, the tapered roller bearing resembles the wide edge of a cone rather than a circle. There are two major benefits to this design. First, true rolling motion is obtained. Secondly and more importantly, the bearing can handle all loads ¨C radial, thrust or both ¨C in any combination. 

Benefits/advantages

g The first benefit of the tapered roller bearing is its cone shaped design. Each roller in the bearing can align itself perfectly between the tapered faces of the cup and cone, without guidance by the cage. That is a major development in bearing design and operation. The large end of each roller has been ground so that it is square against the rib along the back of the inner race . Without the ¡°rib,¡± rollers would be forced from the cage . As each roller revolves about the cone, a wide area of contact is made between the large end of the roller and the rib. This wide area of contact compels each roller to maintain accurate alignment. With each roller perfectly aligned between the two races, the bearing works to maximum productivity. Each roller has an equal share in the total workload. 

The separator, also called the cage, is constructed with an open space over each roller. There are grooves cut in the sides of the roller pockets that correspond to the curvature of the roller when it is in the cage. This permits the rollers to turn evenly, unhampered by cage interference.