An intelligent separated zone oil production technology based on electromagnetic coupling principle

Abstract

To address the challenges associated with existing separated zone oil production technologies, such as incompatibility with pump inspection operations, short effective working life, and poor communication reliability, an innovative electromagnetic coupling intelligent zonal oil production technology has been proposed. The core and accessory tools have been developed and applied in field tests. This technology employs a pipe string structure incorporation a release sub, which separates the production and allocation pipe strings. When the two strings are docked downhole, electromagnetic coupling enables close-range wireless transmission of electrical power and signals between the strings, powering multiple downhole intelligent production allocators (IPAs) and enabling two-way communication. Core tools adapted to the complex working conditions downhole were developed, including downhole electricity & signal transmission equipment based on electromagnetic coupling (EST), IPAs, and ground communication controllers (GCCs). Accessory tools, including large-diameter release sub anchor and cable-crossing packers, have also been technically finalized. Field tests conducted on ten wells in Daqing Oilfield demonstrated that the downhole docking of the two strings was convenient and reliable, and the EST worked stably. Real-time monitoring of flow rate, pressure and temperature in separate layers and regulation of zonal fluid production were also achieved. This technology has enhanced reservoir understanding and achieved practical production results of increased oil output with reduced water cut.