Schaeffler North America


Technical Product Information | 2011-04
Current-Insulating Bearings
Rolling bearings for prevention of damage due to current passage

Traction motor bearings

Deep groove ball bearings

Deep groove ball bearing with ceramic coating

Single-row deep groove ball bearings support radial and axial loads and they are also suitable for high speeds. Deep groove ball bearings cannot be dismantled.

Deep groove ball bearings with current insulation

Damage due to excessive voltage can occur in the bearing supports of electric motors under unfavorable conditions. Magnetic asymmetries, which cannot be completely avoided despite careful manufacturing processes, cause the voltage between the rotor and the stator to drop. The electric circuit is then closed via the bearing.

To prevent this from happening, we supply innovative current-insulated bearings, which also include hybrid bearings with ceramic rolling elements.

  • Inner or outer rings coated with oxide ceramics for breakdown voltages of up to 1000 V
  • Hybrid bearings with rolling elements made of current-insulated ceramic