Characteristics and application of needle roller bearings

Needle roller bearings are equipped with thin and long rollers (the roller length is longer of 3-10 times than the diameter, and the diameter is generally not greater than 5mm), so the radial structure is compact, and its inner diameter and load capacity are the same as other types of bearings. For it’s the smallest diameter, it is especially suitable for supporting structures with limited radial installation dimensions.

According to different applications, bearings without inner ring or bearings with needle roller and cage assembly can be selected. At this time, the journal surface and shell hole surface that match the bearing directly serve as the inner and outer rolling surfaces of the bearing to ensure the load capacity and the running performance is the same as that of the bearing with ring. The hardness, machining accuracy and surface quality of the raceway surface of the shaft or housing hole should be similar to the raceway of the bearing ring. This kind of bearing can only bear radial load.