GMN >> Ball bearings > Products > Special bearings / bearing units > Touchdown bearings > Product information

Touchdown bearings

The use of magnetic bearings gets more and more important for CO₂ laser systems, liquid pumps as well in the optical industry. GMN has successfully been pushing the development and production of touchdown bearings since the mid-nineties.

Optimized engineering

The design of the touchdown bearing arrangement has a major influence on the dynamic behaviour of the shaft during emergency operation.

Important performance criteria are:

• Arrangement of the bearings (rigid, radial and/or axial spring loaded)
  
• Bearing friction
• Acceleration of touch-down bearing masses
• Friction between shaft and bore
• Lubrication

Challenge against touchdown bearings:

• Extremely high acceleration from zero to nominal speed
  (n · dm bis 3,5 · 106 mm/min)
  
• High-impulse radial and axial forces
  
• High frequency of touchdowns
• Limited dimensions
• Poor lubrication
• Low-cost systems
• Aggressive environment applications