Tribodynamic aspects of the resource of electric submersible vane pumps for oil production

Abstract

The operation of electric submersible vane pumps for oil production is accompanied by the presence of solid particles, corrosive substances, asphalt-resin-paraffin deposits in the reservoir fluid, leading to changes in performance characteristics and equipment failures. The reduction of the resource as a result of this is accompanied by an increase in the costs of repair and replacement of equipment. The main processes that negatively affect the failure are the wear of the seals of the working stages, the pump plain bearings and vibration, the level of which can significantly exceed the initial level. A test bench and methodology for testing pump sections for wear in water with an abrasive and simultaneous registration of vibration characteristics have been developed. Two main forms of wear of radial seals have been identified – one-sided and equal-dimensional. The one-sided form of sleeve wear is caused by synchronous shaft precession, whereas the equal-dimensional one is an asynchronous precession, and the vibration level increases with increasing wear. The wear distribution of radial seals along the length of the pump correlates with the shape of the elastic shaft line. The wear of the axial seals does not significantly increase the vibration level. During wear the frequency spectrum of vibrations changes; there occurs a frequency that can serve as a diagnostic sign of ultimate wear of the pump. The calculated dependence of the vibration velocity on the wear of the radial seals of the working stages is obtained, which makes it possible to predict the onset of a failure of functioning.

Keywords

• electric submersible vane pumps
• wear
• vibration
• tribology
• dynamics of the rotor system