Optimization Of Technical Design And Performance Diagnostic For Screw Pump

On the premise of ensuring oil production rate, optimization of technical design forscrew pump is to reduce energy consumption of screw pump oil production system,improvethe system efficiency of screw pump wells, extend the average pump inspection period, makethe system performance more reasonable by rational matching downhole pump, rod and tube,surface equipments; Performance diagnostic is to compare and analyze the theoretical valueduring normal working condition with measured electric current, polished rod torque, rotatespeed, motor power, produced liquid rate, dynamic liquid level and other data, thus somecommon problems,such as breakage and disengage of rod and tube in oil wells,loss,pumpfailure, sand and wax block, can be diagnosed.In the paper, by testing and statistical analyzing the related parameters of oil productionwells for screw pump, combined theory with practice, physical model and mathematicalalgorithm to compute the related parameters of oil production wells for screw pump isestablished. Design and management system software for screw pump has been developed;the software has some functions such as oil wells data management, performance analysisand diagnostic, productivity analysis, parameter optimization and design, equipment datamanagement and so on. Node analysis and calculation method for energy consumption andefficiency is firstly established, three kinds of first degrees,such as management first,efficiency first and oil production rate first, has been proposed to design the paramenters.Thesoftware is used to test and diagnose the screw pump wells, optimize and design theunreasonable parameters of some wells. The software has been revised and improved on thebasis of the field application condition.106wells are diagnosed with the software; totalcoincidence rate is up to93.4%.16wells have been optimized, average system efficiencybefore and after optimization is24.1%and29.7%, respectively, the system efficiency of5.6%is improved, thus the goal of energy-saving and extending the pump inspection period isreached.