Characterization of Wear and Dynamic Performance of Interstage Seals for Electric Submersible Pumps
Abstract
Electric Submersible Pumps (ESPs) increase head of process fluid in oil production from within the well. An ESP comprises of a pump, seal, and motor section oriented vertically. The pump section includes multiple centrifugal pump stages guided radially by interstage seals. ESP mechanical failure most commonly results from severe vibrations in the pump section that increase in magnitude as interstage seal clearances increase. Interstage seals wear from the gas, liquid, and abrasives pumped through them.
This project studies wear, dynamic performance, and leakage of interstage seals for ESPs using a component-level test rig. Silicon carbide, tungsten carbide, and reinforced thermoplastic seals with and without axial grooves are tested. Tests evaluate the impact of different gas concentrations, clearances, and sand concentrations under water lubrication. Results show axial grooves do not significantly impact wear rate, but do significantly increase leakage. Increasing gas volume fraction modestly increases wear rate and induces low frequency vibration orbit variability. Carbide seals have superior wear resistance compared to that of reinforced thermoplastic seals. Radial clearance and sand concentration does not significantly impact wear rate for carbide seals in the range of tested sand concentrations, suggesting sliding wear is the dominant mechanism. Results suggest plain carbide seals should be used in ESPs. Future work should focus on protecting carbide seals from fracture failure, which remains a concern for the integrity of seals.
Subject
SealsElectric Submersible Pumps
wear
three-body abrasion
tungsten carbide
silicon carbide
reinforced thermoplastic
Citation
Hure, Robert Byrd (2019). Characterization of Wear and Dynamic Performance of Interstage Seals for Electric Submersible Pumps. Master's thesis, Texas A&M University. Available electronically from https : / /hdl .handle .net /1969 .1 /200693.