Bearing Service Life - Bosch rexroth IndraDrive Mi KCU02 Project Planning Manual

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Notes on project planning

Bearing service life

Mechanical bearing service life at
increased radial force
Bosch Rexroth AG R911335703_Edition 04
n Average speed for phase t
1m
n Average speed for phase t
2m
n ; n Processing speed
1 2
t ; t Run-up time
H1 H2
t ; t Processing time
1 2
t ; t Braking time
B1 B2
t ; t Standstill time
11 22
Fig. 7-27: Average speed
A complete processing cycle can consist of several phases with different
speeds. In this case, the average is to be generated from all phases.
The nominal service life of the bearings is L10h > 30,000 h (according to
DIN ISO 281, ed. 1990), if the permissible radial and axial forces are not
exceeded.
NOTICE
Possible consequences of inadmissible loads: Premature failure of the
bearings due to increased wear or mechanical damage.
Avoid exceeding the load limits.
Otherwise, the bearing service life is reduced as follows:
L Bearing service life (according to ISO 281, ed. 12/1990)
10h
F Determined allowed radial force in N (newton)
radial
F Actually acting radial force in N (newton)
radial_ist
Fig. 7-28: Calculating the bearing service life L10h if the allowed radial force
F is exceeded
radial
Under no circumstances may the actually acting radial force
F be higher than the maximum allowed radial force
radial_act
F .
radial_max
IndraDrive Mi Drive Systems with KCU02, KSM02,
KMS02/03, KMV03, KNK03, KLC03
+ t + t + t
H1 1 B1 11
+ t + t + t
H2 2 B2 22
Risk of damage by inadmissible loads!