Case Study
Fault Diagnosis for Dyring
Cylinder in Paper Machine
1. Abstract
2. Introduction
The Dryer Section indicated in Figure 1 is part of the paper machine installed at paper making plant with an annual capacity of 300,000 tonnes. Sensor nodes enabling fault diagnosis for this are mounted at the load zone of the spherical roller bearings supporting the rolls at either ends. These sensor nodes communicate to a cloud dashboard and provided comprehensive vibration signal analysis and fault diagnosis. The necessity for installing the system was the unusually high failure-rate among bearings on the dryer section of the plants Valmet paper-machine. Between 2017 and 2022 these sudden failures cost the company in the region of 21 million USD in terms of lost production alone. Inclusion of the costs incurred in overtime payment to the maintenance personnel, ancillary damage caused to the other components by a sudden bearing failure and financial losses due to inability to deliver on schedule would considerably increase the estimate of the losses given above.
Figure 1: Drying Cylinders
3. Background
3.1 Drying Cylinder
Construction
3.2 Sequence
of Events
Figure 2: shows the sequence of events from fault diagnosis to corrective action.
4. Solution
Advanced Fault Diagnosis in IDAP Platform
Figure 3: Increase in Axial Velocity
B. Bearing defects clearly indicated in the frequency plot for bearing 23048 CCK W33 C4
Figure 4: Spectrum plot showing bearing defects
5. Site Inspection and Findings
Figure 7: Severe damage can be observed on the raceways and rolling elements
6. Conclusion
