Sealing performance of oil-free bearings
The oil-free bearing is a new type of smooth bearing that combines the characteristics of metal bearings and oil-free smooth bearings. The metal matrix receives the load, and the specially formulated solid smooth material plays a smooth role. It has the characteristics of high load capacity, impact resistance, high temperature resistance, and strong self-smoothness. It is especially suitable for heavy load, low speed, reciprocating or swinging places where it is difficult to smooth and form an oil film, and it is not afraid of water erosion and other acid erosion And scouring.
The bearing is a component that fixes and reduces the friction coefficient of the load during the mechanical transmission process. Its main function is to support the mechanical rotating body to reduce the mechanical load friction coefficient of the equipment during transmission. According to the different frictional properties of moving elements, bearings can be divided into rolling bearings and sliding bearings.
In order to ensure the smooth and reliable operation of most bearings, most of the bearings are added with smooth oil to stop smoothing. The purpose is to reduce friction and wear inside the bearing and avoid burning sticking: extend the fatigue life of the bearing; discharge friction heat or heat from the outside ; At the same time, the oil film also has a certain ability to absorb vibration.
However, a major drawback of adding smooth oil is that good sealing performance is required, otherwise leakage will occur, and some devices with special requests do not allow leakage of smooth oil, so people use other smooth materials to replace smooth oil, creating Oil-free bearings not only have the advantages of smooth oil-bearing bearings, but also eradicate the environmental pollution caused by leakage. Oil-free bearings mainly include gas smooth bearings, composite data smooth bearings, and water smooth bearings.
Gas smooth bearings are sliding bearings that use gas as a smoothing agent. The commonly used gas smoothing agent is air, and depending on requirements, nitrogen-free, argon-hydrogen, helium oil-free bearings, oil-free bearings, or carbon dioxide can also be used. The mechanism of the gas smooth bearing forming the gas bearing bearing is the same as that of the liquid smooth bearing. Gas smooth bearings use gas transmission f diffusivity, viscosity and thermal conductivity, adsorption and compressibility.