大多数的轴承为了保证轴承工作平稳、可靠，大都添加了润滑油进行润滑，目的是减少轴承内部摩擦及磨损，防止烧粘：延长轴承的疲劳寿命；排出摩擦热、或由外部传来的热；同时油膜还具有一定的吸振能力。
In order to ensure the smooth and reliable operation of most bearings, lubricating oil is mostly added to reduce internal friction and wear of bearings and prevent burning and sticking: prolong the fatigue life of bearings; discharge friction heat, or heat transmitted from outside; at the same time, oil film has a certain vibration absorption capacity.
但是，添加了润滑油一个最大的缺点是需要良好的密封性能，否则会产生泄漏，而有些有特殊要求设备不允许有润滑油的泄漏，于是人们用其他的润滑材料来替代润滑油，发明了无油轴承，使其不仅具有含润滑油轴承的优点，同时杜绝了因泄漏而引起的环境污染。
However, the greatest disadvantage of adding lubricating oil is the need for good sealing performance, otherwise leaks will occur, and some equipment with special requirements do not allow the leakage of lubricating oil, so people use other lubricating materials to replace lubricating oil, invented oil-free bearings, which not only has the advantages of bearing containing lubricating oil, At the same time, the environmental pollution caused by leakage is eliminated.