Damage History; Three Stages To Evaluate A Roller Bearing State - WAGO 750-645 Manual

16 • Condition Monitoring
Machine Condition Monitoring with VIB-I/O Modules
Fig. 2.2.3-4: Shock impulses at bearing damage

2.2.4 Damage History

2.2.4.1 Three Stages to Evaluate a Roller Bearing State

By performing continuous shock impulse measurements, changes in the
bearing condition can be easily detected. The operating time starts at 0 % with
the installation of the bearing and ends with the bearing damage at 100 %. The
diagram below shows the shock impulse values (only peak values) of a normal
roller bearing. 'Normal' means here that the installation and lubrication are
proper and that the bearing is under constantly distributed load. The
continuous increase of the shock impulse values can be traced to material
fatigue and consequential bearing damage.
dB
60
40
20
0
Fig. 2.2.4-1: Lifespan curve
Low deviations of the measured values are quite normal. They can be caused
by temperature changes, changes in bearing load, the time passed since the last
lubrication and other influences during operation.
N
50%
dB
N
60
40
20
0
poor
limited
good
100%
poor
limited
good
Time
g064520e
g064510e
WAGO-I/O-SYSTEM 750
I/O-Modules