The figure below shows a screenshot of the bearing damage on a free-running cylinder in a paper mill. The sampling frequency was intentionally lowered, and the number of samples raised to acquire a measurement of 5 seconds.
In the figure above the “haystack” which is characteristic of a stage 7 or stage 8 bearing fault, is clearly visible including the already created broadband noise. The following figure shows the various stages of bearing damage.
The temperature monitoring on the bearing shows an upward trend over the last month (see figure below). The RMS values (in velocity) however remain stable on all axes during the past month.
Based on these data the decision was made to postpone the maintenance to the next planned maintenance stop.