Root Cause Hypotheses and How to Prevent Failures
The failure of bearings due to the development of white-etching cracks (WEC) in the inner ring of the bearing has become a leading cause of wind turbine gearbox unreliability. The failures are not confined to any single gearbox or bearing manufacturer, but are systemic throughout the industry. The root cause of the failures is not known, although many theories have been proposed and are currently under investigation. Even though the cause of failures is not well understood, risk factors that make a bearing more prone to experience WEC failures are known, as are factors that make a bearing less prone to these failures. By following some simple best practice guidelines in the selection of bearings, WEC bearing failures can be minimised or prevented altogether.
By Rob Budny, President, RBB Engineering, USA
