Rolling bearings: effective protection against electroerosion

October 28. 2016

Rolling bearings: effective protection against electroerosion

Innovative lubricant design ensures better conductivity

The undesirable passage of an electric current and spontaneous discharge can cause severe damage in electric motor rolling bearings. It is with a view to these applications that Klüber Lubrication has developed the new, electroconductive Klüberlectric BQ 72-72. Due to an innovative lubricant design involving dissolved chemical additives, bearings run smoothly and the grease's conductivity is considerably increased to attain specific electrical resistance characteristics resembling those of semiconductors. Furthermore, Klüberlectric BQ 72-72 reliably protects bearings against wear, which contributes to longer maintenance intervals and service lives.


"It is in particular the increasing use of frequency converters for continuous drive speed adjustment that leads to parasitic high-frequency bearing currents, which may damage bearings and reduce their service life considerably," explains Karl Dieter Schuster, Manager Application Engineering at Klüber Lubrication. "Due to the electroconductive additives contained, Klüberlectric BQ 72-72 enables the removal of bearing currents at variable speeds and temperatures. This helps to extend bearing life."


In rolling bearings, currents passing through them can provoke considerable damage to the inner and outer ring as well as the rolling elements. Additionally, there is a risk that the lubricant might be damaged and its performance impaired by the energetic impact. The innovative lubricant additives used in Klüberlectric BQ 72-72 not only contribute to better conductivity, but they also protect the components against wear for a longer bearing life. This was proven by positive results of bench tests and subsequent tribological component and used lubricant analyses.