Bearings with suitable contact angles are selected for the two types of contact angle bearings with different properties and application fields (as shown in Table 1). Select bearings from the dimensions and materials of rolling elements. All spindle bearings in the model have B for large-sized spheres, and the rest are small spheres. Large ball bearings have a higher load capacity than small ball bearings and are therefore more suitable for high load applications. On the contrary, the high-speed adaptability of small ball bearings is better. Ceramic ball bearings have an additional advantage in speed (see FAG spindle bearing data sheet). X-life extra long life bearings consist of Cronidur30 rings and ceramic balls. Small ball X-life bearing designations start with XC, large ball bearings with XCB. The following comparison of spindle bearing specifications and performance parameters can help you choose the right bearing. The contact angle is divided into: 15 25 . Applicable performance options: radial stiffness, axial stiffness, radial system stiffness, radial bearing capacity, axial bearing capacity, radial and axial composite bearing capacity, higher rotational speed and temperature difference between inner and outer rings, T is larger and T is smaller. Selection of application fields: Grinding machine lathes Superfinishing machine tools milling machines Drilling machines with bearing arrangement on the drive side Machining centers Motorized spindles. Ball Size/Ball Material Load Speed u200bu200bLife Bearing Type Large/Steel Ball High Medium Good B Small/Steel Ball Medium High Good HS.. Large/Ceramic Ball Medium High Very Good HCB.. Small/Ceramic Ball Low Highest Best HC.. X-life super long life bearing optimal optimal optimal optimal XC.., XCB....