Gas-driven downhole pumping unit for oil production from directional and horizontal wells

The design of a gas-driven downhole pumping unit for oil production from directional and horizontal wells has been developed. The unit has no rod string, the slide and pneumatic jack are located in the tubing string. Using these units with a compressed associated gas as a working fluid will allow, unlike the hydraulic pumps, avoiding complex surface equipment for preparing the working fluid, maintenance of which is rather labour-consuming, and increasing the reliable operation of slides and downhole pumping units as a whole. In the course of experimental study of the parameters of the proposed installation it was shown on a laboratory bench showed that the fluid feed increases in direct proportion to the rate from 0.6 to 3.6 m/min. There has been obtained an empirical dependence to determine the flow of a borehole pump depending on its geometric parameters, plunger stroke length, stroke speed and gas content in the produced oil. According to the estimated parameters of the developed gas-driven unit, the supply can reach 386 m3/day, which is comparable to the supply of hydraulic units in use.