Optimization Design Of Ground Drive Progressive Cavity Pump Oil Recovery System

The Ground Driving Progressive Cavity Pump oil production is one kind of mechanic oil production technologies, which was developed in1980s.The Progressive Cavity Pump has high Volumetric Efficiency and stable flowing characterizing the centrifugal pump,and it needs less investment and driving energy compared with other technologies. Due to these advantages, the technology of Ground driving Progressive Cavity Pump oil production has being widely used in the oil fields at home or abroad. Because the time of application is not long enough, GDPCP’s theoretical research falls behind the field application. Usually,the choosed pump doesn’t match the working parameters such as Rotational speed, Pump setting depth, and Liquid Rate, making a waste of resources and inhibiting the ability of equipments and layers. This paper proposed that taking the maximized System Efficiency as the target of optimization design for the whole production system.In this research, the model simulating the three kinds of rod string vibration and the model used for Finite element analyzing were developed respectly when considering the rod string’s stress statement and supposed Paritial abrasion. Thus, the position of Guides would be calculated out.PCP’s performance property is the guideline of field application and inproving the efficiency of oil and gas lift.The researchers of Russial Hydraulic Machinary institute established the formulas setting the differential pressure、rotational speed and liquid viscosity as the function of volumetric efficiency and machinary efficiency on the base of indoor experiments results. According to these formulas, the paper has calculated the extent of which those variables can affect the volumetric effciency by means of orthogonal calculation.By the help of other researcher’s formula, the paper has conducted the numerical simulation of PCP’s performance property.This paper, objecting to one oil well, proposed4situations of conducting the optimization of the working parameters. All these ways have repeatly calculated the System efficiencies under different assumptions.And the following work is to find the assumption corresponding to the maximized the value of System efficiencies. In the course of calculating the System efficiencies, the research used nodal analysis method to obtain the pressure profile, setting the node at the pump seting depth. Then, the differential pressure between the pump intake and pump discharge can be calculated out though Multiphase flow method. According to the differential pressure and the patten of the choosed pump, the System efficiencies would be obtained.When the GDPCP was running, Its rod string will undergo Longitude vibration、 Torsional vibration and lateral vibration.This paper developed models simulating these3vibrations and then solved it by numerical methods and Analytical methods.Compared with the vertical well, the stress statement of rod string in the slant well is more complex. The rod strings are liable to collide with the tubes, so this research begins the Finite element analysing of rod string.