Sealing performance of oil-free bearings
Oil-free bearing is a novel smooth bearing that combines the characteristics of metal bearing and oil-free smooth bearing. The metal matrix receives the load, and the specially formulated solid smooth material plays a smooth role. It has the characteristics of high bearing capacity, impact resistance, high temperature resistance, and strong self-smoothing ability. It is especially suitable for heavy loads, low speeds, reciprocating or swinging places that are difficult to smooth and form an oil film, and are not afraid of water washing and other acid erosion And scour.
Bearing is a component that fixes and reduces the friction coefficient of load during mechanical transmission. Its main function is to support the mechanical rotating body to reduce the friction coefficient of the mechanical load during the transmission of the equipment. According to the different friction properties of moving elements, bearings can be divided into rolling bearings and sliding bearings.
In order to ensure that the bearing works smoothly and reliably, most of the bearings add lubricating oil to stop the smoothness, the purpose is to reduce the internal friction and wear of the bearing, and avoid sticking: prolong the fatigue life of the bearing; dissipate the friction heat or the heat transferred from the outside ; At the same time the oil film also has a certain ability to absorb vibration.
However, a major drawback of adding lubricating oil is that it requires good sealing performance, otherwise leakage will occur. Some equipment with special requirements does not allow the leakage of lubricating oil, so people use other lubricating materials to replace lubricating oil, creating Oil-free bearings not only have the advantages of smooth oil bearings, but also eliminate environmental pollution caused by leakage. Oil-free bearings mainly include gas smooth bearings, composite material smooth bearings, and water smooth bearings.
Gas smooth bearing is a sliding bearing that uses gas as a smoothing agent. The commonly used gas smoothing agent is air, and nitrogen, argon, hydrogen, helium, oil-free bearings, or carbon dioxide can also be used as required. The mechanism of the gas-smooth bearing forming the bearing gas film is the same as that of the liquid-smooth bearing. Gas-smooth bearings use gas transmission f diffusivity, viscosity and thermal conductivity, adsorption and shrinkability.