Influence of the Auto-Unloading System on the Rotor Axial Oscillations

Abstract

This paper examines the rotor of a centrifugal pump with an automatic unloading system, which has free axial movement within the end clearance of a hydraulic balancer. The relationship between axial and radial hydrodynamic forces arising in the throttling gaps of the balancing device is demonstrated. Frequency responses of balancing systems are constructed, and an inequality defining the stability limit is obtained. It is noted that automatic balancing systems for the axial forces of a multistage centrifugal pump rotor simultaneously function as a self-adjusting non-contact seal and a loaded angular hydrostatic bearing, significantly determining the vibration state of the rotor.