Electrically insulated bearings – properties and application

Electrically insulated bearings from Nine Star, are provided with an oxide ceramic insulation layer. An overview of the various design variants of the insulation layer is given in the table. Electrically insulated rolling bearings from Nine Star offer exactly the same outer dimensions and technical characteristics as the corresponding uninsulated types.

The most important advantages of these bearings are higher operating reliability, which is assured by optimal protection against electrical corrosion. Electrically insulated bearings are less expensive than, for example, applying insulation to housings or shafts. They are inter changeable with conventional bearings because they have the same key dimensions and technical characteristics. They also offer a reduced risk of damage and thus also longer operating life than conventional bearings when used in electrical machines. When electrically insulated bearings are handled properly, there is no risk of damage to the coating.

The main range of Electrically insulated bearings consists of cylindrical roller bearings and deep groove ball bearings, but all other bearing types can also be electrically isolated. Application areas include traction motors of railway vehicles, electric motors & generators, particularly in conjunction with fast-switching frequency converters.