Bearings; Balancing - Siemens SIMOTICS SD Operating Instructions Manual

Surface cooling by relative movement of cooling air: Type of cooling IC 418 in accordance with
EN / IEC 60034-6
Figure 3-3
3.3.4

Bearings

In order to support the machine shaft and maintain its position in the non-moving part of the
machine, only 2 rolling-contact bearings are used. One roller bearing performs the function
of a location bearing that transfers axial and radial forces from the rotating machine shaft to
the non-moving part of the machine. The second roller bearing is implemented as floating
and support bearing in order to allow thermal expansion inside the machine and transfer
radial forces.
The nominal (calculated) useful life of the bearings according to ISO 281 is at least 20,000
hours with utilization of the permissible radial/axial forces. However, the achievable useful
life of the bearings can be significantly longer in the case of lower forces (e.g. operation with
self-aligning couplings).
Avoid rigid couplings.
Roller bearings with permanent lubrication are maintenance-free. For bearings that can be
relubricated, observe the data on the rating plate or lubricant plate.
3.3.5

Balancing

As standard, the motor is balanced dynamically with a half featherkey (code "H") in
accordance with ISO 8821.
The balance quality corresponds to vibration level "A". Vibration level "B" is optional or
possible on request.
Low-voltage motors
Operating Instructions, 05/2014, 5 610 00000 02 000
IC418
Description
3.3 Installation
21