Aerostatic bearing for large rotor

In cardboard and paper manufacturing, the paper web is handled with large scale rolls. From the machine design point of view, those rolls are large rotors with high stiffness, accuracy and balance requirements. In paper machines, the rotors not only guide the web but also are used to perform different treatments for the manufactured product.
In the cases where highest load and straightness is required, deflection compensated rolls are applied. Commonly, deflection compensated paper machine rolls consist of stationary axle in the middle of the roll and hydrostatically supported rotating shell. Main downside of the traditional deflection compensated roll is high energy consumption. High friction occurs in the hydrostatic system supporting the rotating shell.
In this research, test device was built to perform conceptual investigation of suitability of aerostatic bearings to be applied in the deflection compensated rolls. Porous material aerostatic bearing was built in concave shape to interact with the shell of a roll. The bearing design was a combination of a bearing and a sealed chamber restricted with the bearing itself from the ambient. Air consumption, load and drive motor current were measured at various rotating speeds.
The results of the research show the performance of the investigated bearing at various operating parameters, from which the point of highest performance can be determined. The results suggest that the porous material based aerostatic bearings as a technology is feasible to be applied in the deflection compensation systems. The validation of the feasibility of the concept of the aerostatic deflection compensation enables further investigations into optimizing the performance of the system for widespread utilisation.