Converting Traditional Rod Pumps to New Linear Permanent Magnet Motor Pumps Enhances Economics While Maintaining Productivity

Abstract Conventional lift systems are the primary artificial lift method in oil fields world-wide but, when located near residential areas, can be aesthetically and environmentally undesirable. Replacement of these with new Electric Submersible Plunger Pump system (ESPP) with Linear Permanent Magnet Motor (LPMM) systems is proposed based on successful trials with over 365 days in operation. ESPP's powered by LPMM have been running in Buena Vista Hills field – San Joaquin Valley low-rate wells with reduced downtime compared to wells previously utilizing conventional rod lift systems. The conversion of conventional rod lift systems to the new LPMM does require some surface modifications, but these changes are to the benefit of surrounding communities. The LPMM system has contributed to achieving higher accumulated production due to fewer interventions during the evaluation periods stipulated in our assessment. Substantial savings have been generated from the successful implementation of this new artificial lift solution, including reductions in tubing inspection costs, extra components needed to control tubing wall wear, and costly co-rod units required for installation and removal of the co-rod string in these deviated wells. A special algorithm controls the linear motor speed and assists with challenging operational conditions, such as sand or gas interference. Additionally, monitoring templates have been developed in conjunction with the production engineering team to assist with system surveillance tasks. The variable speed drive (VSD) is adapted from a conventional electric submersible pump controller. The noise reduction of LPMM compared to rod pumps has been measured, showing a reduction in the decibel level generated from the artificial lift equipment. Lost methane from leaking packoff is not easily measured since it is an intermittent phenomenon, but the new system does improve on that issue. Total production increases as a result of the reduced deferred production on frequent rod pump change outs. The power consumption is lower than conventional rod lift systems while maintaining similar production conditions (pump off). These power measurements indicate a reduction in power usage of over 45% compared to conventional rod lift systems. This technology maintains high energy efficiency while eliminating potential leaks from the wellhead stuffing box associated with a rod string. It produces no methane emissions, generates very low noise, and creates minimal surface visual clutter during production activity. Lower cost is derived from the reduction in the number of workover interventions compared to other conventional and unconventional pumping systems. Wholesale conversion to the new LPMM would require time but can be justified with the aforementioned benefits and can be done as workovers are required on existing rod pump wells. The low rate systems that have been successfully trialed will soon have upgrades to higher rate LPMM options that can also run in deeper settings.