Cylindrical Roller Bearings are bearing in which cylinders are used as the rolling elements as opposed to balls in ball bearings. As such, the rollers have a greater (linear) contact area with the outer ring and are distribute loads across a broader surface. Subsequently, they have a relatively high radial load capacity and are suitable for high speeds. Double-row cylindrical roller bearings have high radial rigidity and are used primarily for precision machine tools.
Depending on the series as defined below a number of cylindrical roller bearings have no ribs on either the inner or outer ring, so the rings can move axially relative to each other which can be used as free-end bearings.
Pressed steel (with or without tins or fins) or machined brass cages are generally used, but sometimes molded polyamide cages are also available depending on the application. Cylindrical Roller Bearings are also available without cages with a full complement of rollers. This allows even higher loads but at the expense of speed.
Single row cylindrical roller bearings are also manufactured with snap ring grooves on the outer rings. This design simplifies the bearing joint as the bearings are located into the housing by means of the snap rings. The snap ring groove and snap rings are in accordance with IS0 464.
There are different types designated NU, NJ, NUP, N, NF for single-row bearings, and NNU, NN for double-row bearings depending on the design or absence of side ribs.