To date, one of the most urgent tasks of mechanized oil production is to increase the profitability of well operation, especially low-rate and complicated Fund. One of the promising ways to solve this problem is to improve traditional and develop alternative operating technologies, in particular, plunger pumps with downhole linear drive. The efficiency of plunger pumps is largely determined by the load acting on the plunger. A significant increase in cyclic variable loads on the plunger and drive is due to pressure oscillations in the lift pipes resulting from uneven pump flow during the pumping cycle.
The paper investigates the formation of flow velocity and pressure fields in lift pipes during the operation of wells by plunger pumps with downhole drive. The use of pneumatic compensators aimed at smoothing the flow rate and pressure in lift pipes as part of the pumping unit is proposed. A mathematical model of unsteady fluid flow in the lift pipes of a plunger installation with a system of pneumatic compensators, based on the laws of conservation of mass and momentum for the flow, is developed. The analytical dependence is obtained, which allows to calculate the pressure dynamics at the pump discharge for a given law of change in the pump supply and a given energy intensity of the pneumatic compensator system. Simulation of pumping high-viscosity fluid submersible plunger installation shows that the equipment of the well system of pneumatic compensators can significantly reduce the amplitude of oscillations of speed and pressure in the lift pipes. The maximum load on the pump plunger and drive, as well as the power consumed by the pump unit, is also reduced by reducing the amplitude of the pressure fluctuations at the pump outflow.
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