Experimental Study of Sand Erosion in Multistage Electrical Submersible Pump ESP: Performance Degradation, Wear and Vibration

Zhu, Haiwen (University of Tulsa) | Zhu, Jianjun (University of Tulsa) | Zhou, Zulin (University of Tulsa) | Rutter, Risa (Baker Hughes, a GE company) | Forsberg, Michael (Baker Hughes, a GE company) | Gunter, Shawn (Baker Hughes, a GE company) | Zhang, Hong-Quan (University of Tulsa)

OnePetro 

Abstract

As one of the most widely used artificial lift methods, electrical submersible pumps (ESPs) have been improved gradually since the 1910s. However, its performance and run life are affected by many problems such as gas lock, high viscosity fluid, corrosion, and erosion. With the development of horizontal well drilling and multistage hydraulic fracturing, sand production from unconsolidated sandstone and proppant backflow often cause severe damage to ESPs resulting in reduced operating lifespan. Measuring wear in an ESP pump and monitoring performance degradation is not only very difficult in field cases, but also in experimental studies. The results are precious for understanding the wear mechanism inside an ESP as well as guiding the ESP design and simulation. At the same time, vibration and performance data can provide significant guidance to ESP failure diagnosis, which can potentially reduce the time and cost of well service and extend ESP run life.

Wear processes inside an ESP can be classified by different modes of mechanisms. Erosive wear can be observed in the primary flow channel of the impeller (rotor) and diffuser (stator). Particle strike shroud surfaces and the scratched material is flushed away by fluids. Various semi-mechanistic erosion equations are available to be coupled with Computational Fluid Dynamics (CFD) to predict the erosion in ESPs. In the secondary flow region, balance chamber and sealing rings, particles are presented between the stator and the rotating rotor. Therefore, abrasive wear is believed to dominate the wearing process. Unlike erosion, abrasion is more complicated and abrasion equations are highly depended on geometries, physical mechanism and load between particle and target surface. In this study, a sand wear test flow-loop is designed and constructed to investigate wear in ESPs. Performance degradation, Erosion pattern, abrasion rate, and stage vibration of an ESP were recorded in a 64-hour sandy flow test.