Needle roller bearings are roller bearings with cylindrical rollers that are thin and long relative to their diameter. Such rollers are called needle rollers. Despite having a smaller 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 when the inner diameter and load capacity are the same as other types of bearings, the outer diameter is the smallest, especially suitable for the support structure with limited radial installation size. Depending on the application, a bearing without an inner ring or a needle roller and cage assembly can be selected. At this time, the surface of the journal and the surface of the housing hole matched with the bearing are directly used as the inner and outer rolling surfaces of the bearing. In order to ensure the load capacity and running performance As with 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 type of bearing can only bear radial loads.Generally speaking, 33.3% of needle roller bearing damages are due to fatigue damage, 33.3% are due to poor lubrication, and 33.3% are due to contaminants entering the bearing or improper disposal of equipment. Dust Clean the bearing and the surrounding environment. The fine dust invisible to the naked eye is a powerful killer of the bearing, which can increase the wear, vibration and noise of the bearing. Stamping When the equipment is used, a strong stamping is formed, which is very likely to cause damage to the needle bearing, or use a hammer to directly hit the bearing, and transmit pressure through the rolling body. The impact of non-professional tool installation Use suitable and accurate equipment and tools to use special tools as much as possible, and try to avoid the use of materials such as cloth and short fibers. Whether needle roller bearings are tested in the laboratory or in practical applications, it can be clearly seen that under the same operating conditions, the appearance of needle roller bearings is the same, but their actual service life is very different.