Radial Force (Transverse Force) - Siemens SINAMICS S120 Configuration Manual

Mechanical properties of the motors

3.4 Radial force (transverse force)

3.4 Radial force (transverse force)
Specific radial forces may not be exceeded in order to guarantee perfect operation. The
radial force must not drop below a minimum value on certain shaft heights. This is indicated
in the radial force diagrams.
The radial force diagrams show the radial force F
● at various operating speeds
● as a function of the bearing lifetime
The force diagrams and tables only apply to standard drive shaft ends. If smaller shaft
diameters are used, only reduced radial forces may be transmitted or none at all. With forces
in excess of these values, please contact your local Siemens office.
NOTICE
Motors with option L37 (increased speed) are suitable only for operation without radial
force.
When using elements which increase the force/torque (e.g. gearboxes, brakes), it must be
ensured that the higher forces are not absorbed through the motor.
When using mechanical transmission elements which subject the shaft end to a radial
force, it must be ensured that the maximum limit values specified in the radial force
diagrams are not exceeded.
For applications with an extremely low radial force load, it must be ensured that the motor
shaft is subject to the minimum radial force specified in the diagrams. Low radial forces can
cause the cylindrical-roller bearing to roll in an undefined manner, thereby reducing the
service life of the bearing. For these applications, a single bearing should be selected.
Dimensioning and calculation of the radial force F
Note
The radial forces at the shaft end must be precisely dimensioned according to the guidelines
specified by the belt manufacturer. The belt tension is set by means of appropriate
measuring instruments.
If the belt manufacturer has not provided accurate radial force data, then this can be
appropriately determined using the following formula:
F
R
46
= c • F F
U
R
for a belt output
R
= 2 • 10 • P / (n • D)
7
U
Configuration Manual, (APH4S), 08/2008, 6SN1197-0AD64-0BP1
1PH4 Induction Motors