SDT was tasked with measuring the press washers at a major paper processing plant in Europe.
|||First Press Wash||dBuV
|Second Press Wash||dBuV|
|Opposite Side Hydraulic Motor||bearing 1||-2.4||23||Bearing 1||-7||16.8|
|||bearing 2||4||31.3||Bearing 2||-6.8||18.5|
|Engine Side Hydraulic Motor||bearing 3||18.1||42.6||Bearing 3||17.7||43.1|
|||bearing 4||18.9||42.6||Bearing 4||3.6||31.2|
Ultrasound measurements were taken on 2 press washers, the first rotated at 6 rpm and the second rotated at 7 rpm.
The first press washer had a recorded value if -6.8dBuV, while the second press washer's recorded value was 4 dBuV. The difference between the two press washers is 10.8 dBuV, which show signs of early bearing degradation in the second press washer. It is important to keep a close eye on this bearing and plan for its inevitable replacement.
The time wav forms of the two wash presses are shown below.
The difference in signals can be viewed on the time wave spectrum. On the 7 rpm press washer you can see a solid blue area which is the ultrasonic signature of the rolling and the blue lines are the impacts of the hydraulic motor.
The spectrum for the 6 revs/min press represents a bearing that is degrading.
This events showed anomalies on the rolling bearings of the two press washers. The washer that rotated at 6 revs/min had a measurement of 10.8 dBuV higher than the other washer indicating degredation. It is important to monitor this bearing closely.