High-speed bearings are generally Angular contact ball bearings or deep groove ball bearings. As the ball rolling contact point as a small, relatively light rolling can achieve high performance, speed plot in diameter up to 1 million or more, suitable for high-speed dental drill and high-speed grinding spindle bearings. In these areas the use of bearing cage material with polyimide tube material, and then by mechanical processing methods to obtain the required shape and size. Now commonly used in smaller dental drill bearing, bearing size￠8×￠3×4, the cage is small, there are seven internal￠1 of the ball. Speed ??to reach 350,000rev/min or more to play its performance, it is used in the air turbine dental drill shaft support at the high-pressure air driven turbine high-speed rotation, the head of the dental drill repair teeth. The parts of the bearing working conditions are harsh, the first high-speed series of problems caused due to the high speed, if the cage strong enough, can easily lead to bearing failure resulting fracture.

Bearing lubrication is also more difficult to solve, according to conventional methods, such a high speed bearings should be lubricated with oil and gas installations, atomized by compressed air lubrication oil to the bearings, but because it is used for oral treatment, this method is not allowed, only in the way of working space by adding trace the use of drip oil, the oil bearing part of the vast majority of start-up phase which was thrown face, so very poor bearing lubrication.

Fortunately, bearing continuous working time is not long, compressed air away heat. This bearing should bear 130℃ high temperature of about four hours of continuous disinfection, general engineering plastics are quickly aging, so overall performance is very good use of polyimide, which is polyimide bearings in China industrial application start.

Trial work since 1978, when the method is the use of molding the tubes will be made of polyimide, and then machined to the required size and precision of the cage. Its application is successful, you can make the bearing speed and stability at 350,000 rev / min or more. Noise and bearing the same kind of life to achieve the level of foreign countries. As the process more inefficient, this process cage made of high cost, mass production is not suitable for the needs of modern society, now is the injection molding process using a one-time injection cage method, injection molding process and technology, injection molding materials properties are under study.

In addition to high-speed bearing cage can also be made by the polyimide material. Now the higher price of polyimide, forming more complex process is to limit the promotion of its large number of important reasons. With increasingly sophisticated synthesis technology and increase production, reduce the price of polyimide, development of new materials suitable for injection molding and process methods are the kinds of materials can be used widely in the bearing industry, a necessary condition. It can replace the widely used Bakelite material for high-speed bearings, bearings to improve productivity and performance.