Electric current passage in a gearbox bearing

This case study deals with a gearbox bearing failure in a tire manufacturing plant. It involves RPM measurement troubleshooting and also demonstrates atypical differences in prewarning times between the measuring techniques used.


The plant has been using equipment and monitoring systems from SPM since 2011 to optimize production and prevent downtime. In this case study, an incorrect assembly of the coupling and grounding caused a gearbox bearing failure due to the passage of electric current. The issue was resolved by adequately mounting the coupling and grounding, and the gearbox is now running normally again. The gearboxes in the mixing line are a demanding application for condition monitoring due to their fast-changing output speed and the challenging environment in which they operate.