Special Advantages of Air Bearings

When mentioning bearings, many of us may have some idea about them. We may have heard of some kinds of bearings such as ball bearings, needle bearings, pillow block bearing, etc. But few of us may have an idea about air bearings. I think that most people are new to the concept of them. Then this article may give you an insight into them.

First of all, we should know what the air bearing is. Generally, they have been employed in coordinate measuring machines for 20 years. Unlike contact roller bearings, they utilize a thin film of pressurized air to provide a ‘zero friction’ load bearing interface between surfaces that would otherwise be in contact with each other. They are capable of moving heavy loads of several hundred tons with the minimum of effort by using the air film technology.

As is known to all that common bearing products have many related problems such as friction, wear, and lubricant handling, etc. Being non-contact, air bearings can avoid the traditional bearing-related problems. Besides, they have many technical advantages such as high speed and high precision capabilities near zero friction and wear, and no oil lubrication requirements. All these advantages are distinct which enable these bearings to have special characteristics.

Friction has a direct effect on efficiency. It creates heat which is a bad factor to a bearing. In air bearings, it is a function of air shear from motion, so at zero velocity there would be zero friction making infinite motion resolution theoretically possible. Mechanical wear is another problem to these products. But it can be avoided with air bearings because of their non-contact nature. Speed, acceleration, and loading are not wear factors and they have no influence on the life of the air bearing. Besides, when compared to the rolling element bearings, the load capacity of air bearings is limited. But they can still carry the same load per unit area as traditional plain bearings for machine tools.

Because they are difficult to manufacture, they have not been commercially available before. In my opinion, it is due to their features that they will have a prosperous future. Because of their advantages over rolling element bearings, these products become more and more popular used components in places such as Coordinate Measuring Machines, precision machine tools, semiconductor wafer processing machines, and other clean room, high speed, and precision positioning environments.