PROGRESSIVE 2013

Miniaturization means: The more that small and micro-systems shrink, the greater the importance of cleanliness. GRW bearings are used in applications where very high purity is vital.

The prerequisite for purity: Production facilities and units are flooded again after evacuation - using turbomulecular pumps. GRW ball bearings and special bearings operate inside these high-performance pumps. When the pumps are started up, these bearings accelerate - in a few fractions of a second - from 0 to 60,000 rpm and more.

Special geometries
Bearings made according to customer specifications and with special geometries are used in the areas such as the following:

• As magnetic bearings to support so-called "safety bearings",

• For pumps in the fore-vacuum ranges of approximately 10-4 mbar.

• For high vacuum applications.

Here, GRW uses ceramic balls and cage materials with low outgassing rates. The desired lubrication is provided by greases and oils specifically chosen for the application.

Special lubrication
Conventional lubricants reach their limits when it is extremely hot or cold, or if an ultra high vacuum is reached. But not only extreme environmental conditions call for special lubrication: it may also be necessary near optical systems.

In these cases, GRW uses coatings of gold, silver, MoS2, Teflon (PTFE) or hard material coatings. These layers work as a dry lubricant or as a separating layer. Depending on the material and application, the coatings are applied by electroplating, hammered into the surface, sprayed on, or applied to the surface in vacuum chambers.

The result:
GRW bearings are used successfully at temperatures from 270 ° C to + 450°C and in high vacuum ranges.