are a type of roller bearing comprised of an inner and outer ring, and a number of rows of cylindrical rollers in linear contact with the raceways. These bearings
have a relatively high radial load capacity, making them suitable for high-speed applications. The open flange design and large surface area of the rollers promotes the formation of a lubricant film, which reduces friction, allowing for improved load capacity and speed capabilities. Additionally, the contact surface finish makes these bearings highly reliable and elongates operating life by reducing sensitivity to shaft deflection and misalignment. They are available as single row, double row, or multiple row bearings; each type specializes in different applications. Double row cylindrical bearings are more rigid offering higher radial capacity, and are commonly used for precision machine tools
. Four row cylindrical bearings withstand high amounts of strenuous operation and extreme environmental conditions. In addition to number of rows, variations and improvements will affect the performance level of the bearing. Cylindrical roller bearings are separable and interchangeable, facilitating ease of mounting, dismounting, and maintenance. Some have no ribs on the inner or outer rings, allowing the rings to move axially; this allows the bearing to be used as a free-end bearing. Brass, steel or polyamide cages are often used, however these bearings are also available with no cage, and a full complement of rollers instead, allowing for increased load capacity at the expense of speed.