Techbits: Status of Artificial Lift: Technology and Applications

Abstract

Because water injection is extensively used as a secondary-recovery mechanism in mature fields in Argentina, the Applied Technology Workshop (ATW) on Electrical Submersible Pumps (ESPs) and Progressing Cavity Pumps (PCPs) held in Río Negro, Argentina, garnered intense interest. Because high water cuts are either prevalent or expected to occur in many of these fields, 90 attendees convened in San Carlos de Bariloche to enhance their knowledge of artificial systems through discussion of well-optimization issues, various approaches to resolving these issues, and sharing field-application experiences. Fruitful discussion centered on a variety of topics from PCP elastomer problems to candidate-well selection and from the advantages of automation to mechanical failures in ESPs. Discussion on high-temperature issues, paraffin deposition, effects of corrosion, and practices for cost reduction was combined with multiple case studies to further the learning experience. Building Careers Keynote speaker Atilio Massa, Weatherford Vice President–Latin America Operations, posed this question: “What does the oil and gas industry require from artificial lift systems production and products technical personnel?” In the context of service/producer alignment, Massa emphasized applying an iterative methodology for continuous improvements, going deeply into the fully automated cycle of field operations, and building careers to handle that process (i.e., promoting qualification of employees in the use of new technologies, motivating them to receive continuous training, and ensuring that quality, health, safety, and environment standards are followed). A segment of the meeting was devoted to new artificial lift technologies such as the use of hollow rods. Those have been successfully applied in a variety of conditions in conjunction with the use of PCP technology, but a range of questions remain to be answered, including weight reduction and protection against sensitivity to corrosion. Another technical presentation covered sensors. Not yet a common practice in Argentinean fields, use of downhole pressure and temperature sensors was examined from different viewpoints. It was pointed out that new insights on reservoir behavior, and consequently on production, could be gained. And if components of the ESP supply chain could be supplied from different manufacturers (particularly in the field of sensors), the best interpretation could be had (i.e., pump manufacturers understand pumps, and sensor manufacturers know the most about sensors). Performance having been tested in Brazil’s Campos basin, failures and improvements on the ESP downhole subsurface electric round cable were also discussed, along with continuous-rod systems. It was noted that the advantage of continuous-rod systems is the lack of couplings, the main cause of failure in conventional sucker-rod strings. Presenters entertained questions regarding the logistics required to place the equipment in the well and rod life when submitted to flexion stresses. Reduced operating time and cost-reducing effect of rigless completions formed another segment of the agenda. Such a completion requires a rig to run only the bottomhole assembly (ESP, rod pump, and selective injection equipment). Good planning and daily coordination are essential to good results. Suggestions included the use of coiled tubing for the completion and the addition of memory sensors on the mechanical packers.