During the operation of unidirectional needle roller bearings, it is necessary to regularly coat the surface with lubricating oil, which has many advantages. On the one hand, it can reduce friction and wear inside the bearings and prevent burning and sticking. In this case, the main parts of lubricating oil are the contact parts of the rings, rolling bodies and retainers of the bearings.

For unidirectional needle roller bearings, its fatigue life is also related to lubrication. If the rolling contact surface is lubricated well in the process of bearing rotation, its fatigue life will be prolonged. On the contrary, the fatigue life of needle roller bearings will be shortened if the oil viscosity is low and the lubrication film thickness is not good.

On the other hand, regular application of lubricating oil on one-way needle roller bearings can also discharge heat from friction or heat from outside, play a cooling role, prevent overheating of bearings and aging of lubricating oil itself, etc., and play a positive role in prolonging the service life of components.

In addition, the one-way needle roller bearing surface lubricating oil also has the effect of preventing foreign bodies from intruding into the bearing interior, or preventing rust and corrosion. In addition to applying lubricating oil regularly, we should also master the correct lubrication method. In order to make the bearing function well, first of all, we should choose the suitable lubrication method for use conditions and purposes.

If only considered from the point of view of lubrication, the lubrication of oil lubrication is dominant; however, grease lubrication has the advantage of simplifying the structure around the bearing, so it is necessary to compare the advantages and disadvantages of grease lubrication and oil lubrication, and combine with the actual operating conditions of one-way needle roller bearings.