Method of Automatic Sizing and Selection of Tapered Electrical Submersible Pump System Based on Multiple Operating Cases

A tapered Electrical Submersible Pump (ESP) is frequently utilized for dewatering flooded gas wells, where each production stage exhibits significant variation. However, conventional ESP sizing procedures typically focus on a single operating case and a singular pump model. As such, the sizing and selection of a tapered ESP necessitates the designer to adeptly coordinate pump models, stage numbers, and operating frequencies for each distinct operating case, often relying heavily on experience. To address this challenge, a procedure for automatically sizing and selecting tapered ESPs based on multiple operating cases is introduced. The analysis focuses on key nodes including the pump intake (or gas separator), discharge, and the connecting point between the two pumps. Parameters for each node are computed for each case, encompassing variables such as pressure, Gas Volume Fraction (GVF), density, and more. Pumps are then sized and selected in a bottom-up manner based on node data. Additionally, once a bottom pump is selected, the node data is updated to facilitate the design of the top pump. This procedure enables the calculation of node parameters across multiple operating cases, determination of the requisite tapered ESP models from the ESP database, computation of stage numbers for each pump, and establishment of appropriate operating frequencies for each case. Subsequently, the selected pumps undergo verification to ensure normal operation within the Recommended Operation Range (ROR) for every operating case. The feasibility of this method is demonstrated through an illustrative example. Results indicate that the selected pumps consistently operate within their RORs across all operating conditions, thereby ensuring normal operation without accelerated wear and extending the pump inspection cycle.