Understanding Vertical Motor Bearing Systems and Minimizing their Failures

The number one reason for the removal of vertical motors from service is the failure of the bearing system. These systems can be much more complicated than those used in horizontal motors.The purpose of this paper is to present the various bearing systems used on vertical motors and the reasons why these systems can fail prematurely. Suggestions will be given for extending the bearing life including how to specify these bearings and their accessories correctly. The scope of this paper includes motors up to 5000 hp, all speeds and enclosures.