Innovative Practices for Electrical Submersible Pump (ESP) Efficiency: New Gas Lift Mandrel (GLM) Deployment Techniques

Abstract

Gas lock is one of the key challenges that Electrical Submersible Pumps (ESPs) faces in oil wells with high Gas Oil Ratio (GOR). For wells with ESP packer or wells with no continuous gas bleed-off through the annulus, gas accumulates below the packer until it reaches the pump intake, creating what is known as gas lock. As a result, ESP motor temperature increases (due to no cooling fluid), causing ESPs to trip. As a mitigation for this challenge, the innovative idea of ​​installing Gas Lift Mandrel (GLM) below the ESP packer deployed to enable continuous gas bleed-off from the annulus to tubing above the ESP. As a results, oil deferent reduced, ESP run life extended and intervention cost avoided. Oil wells with gas lock issues or gas lock potential were selected using ESP historical running parameters and production testing data. Selected wells were attended by a well pulling hoist (WPH) where GLMs were installed. Side pocket mandrels with dummy valves were installed by WPH below the ESP packer and slick line later replaced the dummy valves with gas lift valves (GLV). these valves are set to open at the minimum differential pressure between annulus and tubing where gas will be bled off automatically before reaching the ESP intake. Hence, preventing gas lock phenomena. The idea has already been implemented in more than 25 ESP wells in more than seven different fields. Better ESP efficiency, reduction in oil deferment and extended ESP run life was evident. The opening and closing of the valve were noticed in the ESP trend where it was seen as spikes in pump discharge, electrical current, and THP. To confirm the opening and closing of the valves, two memory density gauges were installed, above and below the GLM. The opening of the valve was confirmed by a sharp drop in density at the above valve only (indicating gas flow from annulus to tubing above the ESP, though the GLM). Installing GLM in ESP wells to prevent the gas lock issue is a new novel approach that combines both low cost and highly efficient practices. The cost of GLM is low, the installation has no complexity when compared to some other existing solutions that are designed to bleed the gas from below the packer. It also serves as an SSD where the GLV can be retrieved by slick line if needed for any reason.