ДИНАМИКА СКОРОСТИ ПОТОКА И ДАВЛЕНИЯ В ЛИФТОВЫХ ТРУБАХ УСТАНОВОК ПЛУНЖЕРНЫХ НАСОСОВ С ПОГРУЖНЫМ ПРИВОДОМ

Abstract

Background Significant progress has been achieved in improving the design of sucker rod pump units (SRPU), which have the highest efficiency in comparison with alternative methods of mechanized production during the operation of low flow rate production wells. Successful development of scientifically-based methods for selecting and optimizing the operation mode of sucker rod wells is being carried out, thanks to which efficient SRPU production of oil is achieved over a wide range of changes in production parameters. However, it should be noted that when operating wells with rod installations, there are significant limitations associated with the presence in the system of the pumping unit and the string of pump rods. Aims and Objectives Mathematical modeling of hydrodynamic processes in lift pipes and wells flow lines with the aim of calculating the pneumocompensators optimal geometric dimensions and technological parameters, predicting changes in their characteristics when changing the well operating mode. Results The mechanisms and features of the flow velocity and pressure in the lift pipes and flow lines of the wells equipped with plunger pump units with a linear drive are investigated. A mathematical model of the unsteady flow of a gas-liquid mixture is proposed. The analysis of the formation of the pressure field and the flow velocity in the cavity of the lift pipes during pumping of the produced products is presented. Simulation of the pumping out of high-viscosity oil and water-oil emulsion by the plunger pumps with a linear drive showed that with an increase in the viscosity of the fluid, the oscillation amplitude at the pump tip increases. At the mouth, with an increase in viscosity to 0.1 Paˑs, the amplitude of pressure fluctuations decreases, and with a further increase to 0.2 Paˑs, it increases. Calculations show that with an increase in the gas content of oil, the amplitude of the pressure fluctuations at the pump cradle and at the mouth decreases, which is associated with the damping properties of the gas due to its high compressibility, as well as a decrease in the viscosity of the gas-liquid mixture with increasing volume gas shares in well production. By modeling the pumping out of highly watered oil, it was shown that the pressure fluctuations formed during its flow are insignificant. In accordance with the simulation results, it was concluded that when pumping out highly viscous products (viscosity more than 0.05 Paˑs), the greatest effect due to equalization of the fluid flow rate in the pipes can be obtained when the well is equipped with deep pneumatic compensators, for example, placement of pneumatic compensators on the pump side and higher in depth.