Matched set super precision bearings: Factors to consider
There are many reasons for the use of precision grade bearings. The selection of type and size are specific to the application. Some of the determining factors are load ratings, both radial and axial, operating speeds, temperature and the degree of accuracy during operation. Bearings are made to exacting tolerances and are rated in various levels of accuracy. These standards were established by the Annular Bearing Engineers' Committee (ABEC) for the American Bearing Manufacturers Association which has been the benchmark in the industry since the early 1900s. The ABEC scale classifies different accuracy and tolerance ranges into classifications 1, 3, 5, 7 and 9. These classifications or grades are issued to a bearing after a series of vigorous measuring and testing procedures have been completed. With higher ABEC grades, an increase in running accuracy, speed and performance can be achieved.