Winder Vibration

Winders are complex rotating machines with a number of rotating components. The speeds of these components are related to their respective diameters and the paper speed. With the paper speed accelerating during the start of the set, decelerating at the end of the set and the possibility of speed changes during the set, the paper speed is a critical component to monitor. While the winder speed changes, the parent reel diameter and the set diameter constantly change. Even when the winder is operating at constant speed, the speeds of these components change.
 

For this reason the vibration of the winder must be related to the paper speed, the set rotational speed and sometimes to the parent reel rotational speed. These speeds are obtained with tachometers. Advanced transient analysis techniques, such at the time varying discrete Fourier transform (TVDFT) have been imlemented by Spectrum Technologies for this analysis.
 

The vibration will point to the component of the winder from which the vibration is originating. It may not directly point to the root cause of the problem but knowing the component from which the vibration is originating, and looking at the spectra shape, the most likely causes can often be determined. In some cases models of potential problems have been developed to determine if the resulting vibration is similar to the measured vibration. This has greatly aided in resolving problems.
 

Dynamics of winders is a complex problem, and constitutes an area for which there is not a great deal of published literature. Spectrum Technologies has been involved in resolving a number of these problems over the years. Our work has covered many winders, making a variety of grades of paper, hence a range of problems have been encountered and solved. In some instances the vibration testing has been repeated to determine the effect of remedial work.