Needle roller bearings are roller bearings with cylindrical rollers, relative to its diameter, rollers are thin and long. This roller is called a needle roller. Although has a small cross-section, bearing still has high load capacity, needle bearing with fine and long roller (roller diameter D 5 mm or less, acuity 2.5 L/D, L) for the roller length, so the radial structure is compact, its diameter and load capacity at the same time, with other types of bearing outside diameter to a minimum, especially suitable for the limited size of the radial installation supporting structure.

 According to the use of different occasions, can be used without inner ring of the bearing or needle roller and cage components, at this time to suit the bearing surface of the surface of the shaft and the shell hole directly as inner and outer rolling bearing surface, in order to ensure the load capacity and operation performance and you have the same ring bearing, axis or shell hole hardness on the surface of the raceway, machining accuracy and surface quality should be as a bearing ring raceway. This kind of bearing can bear radial load only.