The advantages and disadvantages of gas lubricated bearing and its application

The advantages of gas lubrication bearings: ( 1) The smallest viscosity and friction. According to the fluid mechanics, the viscosity of the gas only one over one thousand of the lubricating oil, so the friction force increases, the lower, generally in the engineering application of the friction force and the heating and temperature rise is often neglected. At the same time it can be used in the low speed movement and does not produce the crawling phenomenon. ( 2) High precision and good accuracy stable. The lubricating oil gas compressibility, the compensation on the surface of the parts machining error of the uniform, make the gas bearing or guide the work of the error is only about a quarter of the machining error. ( 3) Good adaptability to work environment. Because of the influence of temperature on the viscosity of the gas is small, so the gas lubricated bearing a plain bearing operating temperature range is much wider, it can be said that the task of gas lubricated bearing temperature range depends on the bearing can withstand the temperature of the material. Gas lubricated bearing lubrication of the medium for gas, in use process will not damage to the equipment and working environment, particularly important in nuclear reaction auxiliary equipment and medical equipment. ( 4) Working stability is good. Gas lubricated bearing in the use of basic no wear or minimal wear and tear, so reduces the maintenance work. A - is the stability of the whole system To help. Gas lubricated bearing faults: ( 1) Low bearing capacity, stiffness. However, with the development of research work, the bearing capacity and stiffness has been changed. Developed by the radial stiffness of air bearing has reached to 876 n/um, thrust bearing stiffness has amounted to 2630 n/um. It is enough to meet the superfinishing. ( 2) Higher requirements for air quality. Before the gas supply to gas filtering impurities, drying, etc, to prevent clogging gap. ( 3) Surface of the bearing surface quality and higher tolerance requirement. For example, its roughness to less than 100 & mu; m。 ( 4) Self-excitation generating vortex. The application of gas lubrication bearings: ( 1) Applied in high precision measuring instruments. With the development of ultra-precision and, at the same time, development and measuring instruments to meet the measurement requirement of precision parts. The working precision of measuring instruments largely depends on the movement precision of the moving parts. The application of gas bearing in inertial navigation, officially opened the gas lubrication bearings in the application of precision measuring instruments. Three coordinates of the spindle and the guide rail, roundness instrument friction torque meter main shaft and the guide rail, with gas lubricated bearing support from the end of the 60 s, the accuracy of 1 ~ 2 orders of magnitude. Germany FAG bearing the company's large-scale measurement instruments and workbench series by gas bearing and guide rail. ( 2) Used in precision machining. High machining precision depends on the work of high precision machine tools. A machine tool machining accuracy depends on the high rotation precision and high speed spindle, high and straightness without crawling guide rail and micro feed mechanism. Y - from the United States Factory produced Duqont1 #, 12 # Duqont2 superfinishing machine used graphite air bearing up gas lubrication bearing is widely used in the ultra precision machinery. ( 3) The application of other industries. In the computer industry in the manufacturing of large scale integrated circuit workbench USES air bearing; In the medical devices used in the high-speed drill, at the same time in the textile machinery and food machinery industry has even applied, it serves to show the gas lubrication bearing is widely used.