Research on the operation of a device for influencing the bottomhole zone of wells in depleted fields

The development of wells in the late stages of oil and gas field development is complicated by contamination of the bottomhole zone with process fluids due to a significant decrease in reservoir pressure. Existing methods of cleaning tubing or drill pipes to restore permeability are often ineffective due to the small volume of these pipes, the lack of measurements of the pressure drops generated, and the use of special equipment and maintenance services. Therefore, the aim was to study a device for influencing the bottomhole zone of the formation, which involves conducting suction not through tubing, but through a production string, measuring the magnitude of depressions-repressions, as well as the possibility of performing these works directly by the drilling crew. Theoretical, experimental and industrial research made it possible to create a device, the advantage of which is that its use makes it possible to significantly increase the magnitude of the depressions created, measure the depressions created, and record the curve of reservoir pressure recovery during swabbing. In addition, no additional equipment (geophysical drawworks, packer, etc.) was used except for that available to the drilling crew or overhaul crew. Dynamic stimulation of the well was achieved by creating hydrodynamic cyclic loads (depressions, repressions) on the bottomhole zone of the formation in order to clean it from contamination. The possibilities of creating cycles of depression-repression, their magnitude, and the loads that arise during swabbing were investigated. The possibility of conducting hydrodynamic studies in unstable modes with the removal of the pressure recovery curve directly during the swabbing process was proven. In addition, during the well development process, the device design provided for hydrodynamic studies. The device was successfully implemented at two wells in the Carpathian Region