Roller Bearings are similar to Ball Bearings except that the Rolling Element is a Roller instead of a Ball. The Roller can be Cylindrical, Spherical or Tapered in shape with matching Raceway profiles on the Rings or the Washers.
Since the contact area between a roller and its corresponding raceway is more than the contact area between a ball and its corresponding raceway, the Load Carrying Capacity of a Rolling Bearing is generally much higher than that of a Ball Bearing.
Depending on the Roller Shape and Dimensions, Roller Bearings are classified into Cylindrical Roller Bearings, Spherical Roller Bearings, Tapered Roller Bearings and Needle Roller Bearings. Roller Bearings are further classified into Radial and Thrust Bearings based on their Primary Load Carrying Direction.