Kit, method and apparatus for monitoring operation of a bearing assembly, method for producing said apparatus and bearing assembly with a condition monitor


This invention relates in general to a method of monitoring bearing assemblies, and, in particular, to the accurate, non-invasive monitoring of bearing assemblies in use. Skidding is the principal cause of wear and can be an indicator of problems developing within the bearing. It is generally a high-speed phenomenon where the ratio between inner and outer race-bearing element change under different operating conditions, like change in lubricating oil flow, change in oil viscosity, loading, damage to roller elements or bearing surfaces etc. For example, increasing bearing applied load to the bearing can decrease skidding, but will tend to increase bearing fatigue, reducing bearing life, so a compromise must be reached. A technique for determining properties of a bearing assembly in use involves using an eddy current probe for detecting changes in material density within a raceway of the bearing assembly. It can be used in harsh conditions. It can withstand low and high temperatures, high pressure, withstand aggressive chemical and high volume lubricating oil environments.

Technology transfer

This technology is available for licensing. There is an opportunity for this invention to be developed for particular applications and for demonstration of the final product through a collaborative research project. The business opportunity may be referred to by its NRC ID: 11876

Market applications

There are various industrial applications in a number of sectors for the use of this patent from aerospace to manufacturing.

How it works

A field of detection of the eddy current probe enters the bearing raceway intermediate races that define the raceway, and as such the detection is of the bearing elements. There is no need to modify the housing that supports the outer race like other commercial products where the probe is directed through the bearing support wall which cause deflections in the raceway as a rolling element passes by, putting unneeded fatigue on the raceway that decreases overall bearing service life. A fixture mounting the probe in a stable position with the tip of the probe proximate to a raceway of the bearing assembly so that part of the spatial region enters the raceway at a position intermediate opposing races is all that is needed.


  • Does not require modification or removal of housing supporting the races
  • Can be applied in all settings: laboratory, controlled or in machine use (industrial and manufacturing)
  • May be tested in isolation, as a part of a machine, or as a whole machine
  • May be part of a diagnostic or prognostic investigation
  • Can be used in low/high temperature environments and is impervious to oil.
  • May be performed on a bearing assembly for constant monitoring, scheduled maintenance or suspected of approaching end of service life


NRC file 11876:


To inquire about this technology, please contact:

Matt Tobin, Business Advisor
Telephone: 613-990-0765

Express Licensing

NRC makes research & development licenses for this technology available under its Express Licensing program. To purchase such a license, please complete the Express Licensing order form.

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