Needle bearings are roller bearings with cylindrical rollers, which are thin and long relative to their diameter. This kind of roller is called a needle roller. Despite having a small cross-section, the bearing still has a high load bearing capacity, needle roller bearings are equipped with thin and long rollers (roller diameter D≤5mm, L/D≥2.5, L is the length of the roller), so The radial structure is compact, and its inner diameter and load capacity are the same as other types of bearings, and the outer diameter is the smallest. It is especially suitable for supporting structures with restricted radial installation dimensions.
According to different applications, bearings without inner ring or needle roller and cage components can be selected. At this time, the journal surface and shell hole surface matching the bearing directly serve as the inner and outer rolling surfaces of the bearing to ensure load capacity and running performance Same as 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.