**4. Optimization of the spindle-bearing system in relation to temperature**

In addition to the bearing arrangements, the temperature properties of the bearing supporting node have an increasingly greater significance on the high-speed capability of the bearing. The main goal of this section is to show the SHS design under real operating conditions, taking into consideration the temperature-related behaviour of the spindle and bearing nodes.

The value of the changes in SHS temperature depends on the temperature gradient, the type of bearing arrangement (DB, DF, DT, …), the contact angle of the bearing, and the distance between the bearings arranged in the node.

The stiffness of the given example was analysed using the application software "*Spindle Headstock"* [3], developed in our department.

The analysis identified the optimal stiffness, which was then applied to the headstock of the DB 24 fy. Ex-Cell-O GmbH., Eislinger precision boring machine, Figure 11, [18]

The headstock used for analysis had the following parameters:


**Figure 11.** The Headstock of the precision boring machine DB 24 fy. Ex-Cell-O GmbH., Eislinger, [18]

**Figure 12.** Model of the spindle

**Figure 10.** Variation of stiffness with bearing arrangement parameters

**Figure 11.** The Headstock of the precision boring machine DB 24 fy. Ex-Cell-O GmbH., Eislinger, [18]

**Figure 12.** Model of the spindle


68 Performance Evaluation of Bearings

**Figure 10.** Variation of stiffness with bearing arrangement parameters

