The Devel Opment Of Screw Pump Well Metering Device In The Cyclic Process

In Daqing oilfield’s circular gathering and transferring process, the production of screw pumps can’t be measured, and screw pumps’working condition diagnosis are difficult.The measurement of the conventional screw pump well is influenced by the region, the time and the environment, and the measurement error is big, and can’t meet the need of oil field production. Aswell, we can’t accurately determine the downhole operation under the condition of the current screw pump well.And its operation is so complex that these screw pumps have many drawbacks in the production and safety.In view of the above problems, this paper presents a solution to the problem by the establishment of output measurement model, working condition diagnosis model and dimensionless control chart of screw pump well.The annulus surface of the screw pump changes by the production parameters of the ground, we analyzed the relationship between continued the annulus flow and single well production in the variable operation condition, and considered the effect of pump efficiency on the yield, and analyzed the relationship between the transmission efficiency of the drive device and the load, And then established the relationship between active power, torque and rotational speed.All above work forms the theory based on the electrical parameters of the measurement of the output of the screw pump.Based on the research of the screw pump’s condition diagnosis technology,the relationship between the rod torque, friction torque and liquid surface is established under the condition of parameter variation.By testing the data of different operating parameters, the active torque and the friction torque between the rod string and Production fluid can be calculated.Through the comparison of the two above values, the various operating conditions of the screw pump lifting system including sucker rod break off and string wax and pipe leakage can be reflected directly, in this way, Screw pump well working conditions can be directly and accurately diagnosed. This is a new production measurement device and working condition diagnosis method for screw pump wells in Daqing oilfield’s circular gathering and transferring process.There is a large error in the dynamic control chart of the screw pump well, So The relationship between the displacement efficiency and horizontal coordinates that the flow pressure of the screw pump well must be studied, and thenon-dimensional macro control chart whose ratio between the bottom hole flowing pressure and the optimum bottom hole flow pressure can be established. Next, the control chart software of macro-dynamic control chart is developed, which can help to judge the working condition of screw pump well and guide well workover.