Schaeffler North America


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

Traction motor bearings

Cylindrical roller bearings

Cylindrical roller bearing with a one-piece solid brass cage
Current-insulated bearings

For decades, cylindrical roller bearings have stood the test in traction motor bearing supports of all types in main line and light rail vehicles. Successive further development has ensured that their efficiency has been optimized to meet the requirements of modern railway vehicles.

Single-row cylindrical roller bearings offer an advantage over other conventional bearing designs because of how easy they are to dismantle in the inner and outer rings with a roller and cage assembly. This means that the user is offered practical benefits with regards to assembly, dismantling, maintenance and inspection. FAG cylindrical roller bearings have a modified linear contact between the rollers and the raceway to prevent edge stresses.

Cylindrical roller 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