ABMA 9:2015 (R2020) ✓ Most Recent

Following significant discussion and debate within the United States bearing industry and user base, revisions have been made to ANSI/ABMA 9:1990 - "Load Ratings And Fatigue Life For Ball Bearings" to make it more consistent with ISO 281 (Rolling bearings - Dynamic load ratings and fatigue life) and ISO 76 (Rolling bearings - Static load ratings). These revisions are also aligned with the recent revisions to ANSI/ABMA 11: 2014 - "Load Ratings and Fatigue Life for Roller Bearings". The ANSI/ABMA standards are now aligned with the rating calculations given in the ISO standards. However, the detail of the life adjustment for operating conditions has not been adopted due to concern among the different industry and user communities. In addition to updated rating calculations, the guidelines for the estimation of the required lubricant viscosity for the application and lubrication viscosity ratio have been included to assist the designer in lubricant viscosity selection.

Ball bearing performance is a function of many variables. These include the bearing design, the characteristics of the material from which the bearings are made, the way in which they are manufactured, as well as many variables associated with their application. The only sure way to establish the satisfactory operation of a bearing selected for a specific application is by actual performance in the application. As this is often impractical, another basis is required to estimate the suitability of a particular bearing for a given application. This is the purpose of this standard.

This standard specifies the method of calculating the basic dynamic load rating of rolling bearings within the size ranges shown in the relevant ANSI/ABMA standards, manufactured from contemporary, commonly used, good quality hardened bearing steel in accordance with good manufacturing practice and basically of conventional design as regards the shape of rolling contact surfaces.

This standard also specifies the method of calculating the basic rating life, which is the life associated with 90% reliability, with commonly used high quality material, good manufacturing quality and with conventional operating conditions. In addition, it specifies the method of calculating adjusted rating life, in which various reliabilities, special bearing properties and specific operating conditions are taken into account by means of life adjustment factors.

Furthermore, this standard specifies the method of calculating the basic static load rating and the static equivalent load for ball bearings within the size ranges shown in the relevant ANSI/ABMA Standards, manufactured from good quality hardened bearing steel, in accordance with good manufacturing practice and basically of conventional design as regards the shape of rolling contact surfaces. See more