KOHTECT BT-77
For instance, at the shock acceleration amplitude measuring of a well lubricated and
correctly installed bearing, the dB
m
is only slightly higher than dB
c
. But when one
measures shock acceleration amplitude of a bearing having faults, these faults are
detected by dB
m
maximum values, at that, the background dB
c
value depends on the
lubrication condition, and can grow increase substantially when there is insufficient
lubrication followed by frequent metal-to-metal contacts.
Increase of dB
c
background value may be caused by other reasons as well, e.g. at the
drive coupling misalignment. It is easy to distinguish between these cases – with the
coupling misalignment there will be the same picture for the bearings on the both sides
of the coupling.
Results of the shock acceleration amplitude measurement for drives bearings can be
influenced by shocks produced during the running in of a gear mesh, which can be
transferred onto the bearings. However, mostly the gear teeth hum is so low that does
not impede the measurement.
With the shocks, originated by the gear wheels defects, the dB
m
Max ��alue increases
sharply for the two bearings simultaneously (on both sides of gear).
The greatest effect from the technical state monitoring of bearings is reached when
measuring results are being put on graph against the time factor. At this, a forecast of
the technical state becomes possible. Example of the measurements results processing
is given in Table-1.0 .
1.4 Tachometer
The TI-7 tachometer operation is based on the measurement of frequency of infrared
ray return from the reflective tape (or another marker) fixed on the turning shaft. A white
marker pen is provides in the package so that user can mark the rotor to get good
5
Summary of Contents for BT-77
Page 1: ...BT 77 Bearing Tester with Non Contact Tacho Operating Instruction Manual...
Page 2: ......
Page 4: ...KOHTECT BT 77...
