Not All Thin-Section Bearings Are Created Equal - February 2011
Robert Roos and Scott Hansen
The article "Not All Thin-Section Bearings Are Created Equal" appeared in the February 2011 issue of Power Transmission Engineering.
American Bearing Manufacturers Association (ABMA) Standard 9 and ISO 281 give equations for calculating the basic dynamic radial load rating for ball bearings. These equations are based on a number of assumptions, many of which are not valid for thin-section bearings. (Thin-section bearings are described in ABMA standard 26.2.) Nevertheless, many thin-section bearing catalogs report load ratings based on these equations. Kaydon has developed a new method for calculating the dynamic radial load rating for thin-section ball bearings. The new method uses the contact stress and the number of stress-cycles-per-revolution to calculate the capacity. The new numbers are based on five years of actual test results. These equations can also be used to calculate the dynamic radial load rating for four-point contact ball bearings, which are not covered in ABMA standard 9 or ISO 281.
The article "Not All Thin-Section Bearings Are Created Equal" should appear in the box below, but if you do not see it, you can download it here.