Needle roller bearing

Needle Roller Bearings - Inch and Metric

Needle roller bearings are essentially cylindrical roller bearings except that their cylindrical rollers have a length 3 to 10 times their diameter (versus a length less than 3 times their diameter). Needle bearings are also essentially bearings that utilize small & cylindric rollers. Therefore, the ratio of the bearing outside diameter to the inscribed circle diameter is small, and they have a rather high radial load capacity. Even though they have a low cross section, needle roller bearings have a high radial load capacity and are exceptionally apt for bearing applications where radial space is limited.

There are numerous types available, and many have no inner rings

There are numerous types available, and many have no inner rings. The drawn-cup type has a pressed steel outer ring and the precision (solid) type has a machined outer ring. There are also cage-and-roller assemblies without rings. Most bearings have pressed steel cages, but some are without cages.

Drawn cup needle roller bearings have a drawn outer shell serving as a raceway for the rollers and are installed with a press fit in the housing. They are ideal for many of the following applications: transmissions, transfer cases, engines, valve trains, steering and braking systems, axle supports, outboard engines, textile industry, power tools, copiers, fax machines, paper-moving equipment, and appliances.