subject: Knowledge about Applications and Types of Air Bearings [print this page] Air bearings are quite new to most peopleAir bearings are quite new to most people. Although they are not as popular as some other kinds of bearings, they are still very important in many aspects. Due to their importance, I think it is rather necessary for us to learn something about them.
Aerodynamic bearings and aerostatic bearings are two basic types of precision air bearings. Compared to bearing types such as ball bearings and needle bearings, these two kinds seem like rather complicated. Let us look at the first type: aerodynamic bearings. They depend on relative motion between the bearing surfaces and usually some type of spiral grooves to draw the air between the bearing lands. This kind of bearings are often referred to as foil bearings or self-acting bearings. There are many examples about them like thrust bearings for electrical generator turbines.
Then it's time to study about the second category: aerostatic bearings. This type of bearings require an external pressurized air source which is introduced between bearing surfaces by precision holes, grooves, steps or porous compensation techniques. It is due the air source that these bearings can maintain an air gap in the absence of relative motion between the bearing surfaces.
Air bearings have a wide range of applications. They can be applied in testing equipments, high speed equipments, and accurate machine tools, etc. Air bearings have may special advantages. For example, they have high speed and high precision capabilities near zero friction and wear, and no oil lubrication requirements. Because of their advantages, many testing machines use air bearings to eliminate mechanical contact friction. The elimination of friction dramatically increases resolution of the instrument. Additionally, air bearing also plays a very important role in the high speed equipments. Because it is not reasonable to try to do accelerated life testing on such machines, the changing of bearing technology becomes a choice. When using this kind of bearings, the speed or distance the bearing travels does not affect wear. Beside, the mode of wear is erosion. Therefore, air bearings enable these equipments to perform well and have longer service life.
All in all, air bearings have so many advantages that they can have many special functions in various applications. Thus, the appropriate use of them may bring you some unexpected results.
Knowledge about Applications and Types of Air Bearings
