Page 196 of catalogue Super Precision Bearings of Schaeffler Technologies GmbH & Co. KG

Bearing arrangement design and application examples
Selection of suitable bearing contact angles · Selection of bearings in terms of ball size and materials

Selection of suitable bearing contact angles Both available contact angles have different preferences and application areas (see Table 1).

Contact Angle Preferences

15°

25°

Radial rigidity Radial load carrying capacity Higher speed with small ΔT Applications

Selection of bearings in terms of ball size and materials All Spindle bearings that have a “B” in their type description are filled with large balls and the rest have small balls. Bearings with large balls exhibit higher load carrying capacity and are thus better suited for higher loads than those with small balls. In contrast, the latter is preferred over this when high speeds are required. Bearings with ceramic rolling elements have an additional speed advantage over this (see section Bearing Tables, spindle bearings). X-life ultra bearings are always made with Cronidur 30 rings and ceramic balls. Small Ball bearings of this model type begin with an XC type description. Large ball bearings begin with type description XCB. The following comparison of the specifications and performance data of spindle bearings is helpful for proper bearing selection.

Axial rigidity Radial system rigidity Axial load carrying capacity Combined radial and axial load capacity High ΔT between IR and AR

Grinding Machines Turning machinery Super finishing machines Milling machines Belt side of bearing arrangement Drills Machining centres Motor spindles
1: Bearing contact angle selection criteria

Ball Size/ Ball material Bearing type Size/Steel B… Small/Steel HS.. Size/Ceramic HCB.. Small/Ceramic HC.. X-life ultra bearings XC.., XCB..

Load

Speeds

Service Life

High

Medium

Good

Middle

High

Better

Middle

High

Much better

Low

Highest

Best

Premium

Premium

Premium

2: Performance comparison of different ball size and material

195

Design