Numerical Simulation Analysis And Experimental Research Of The Pumping Wells System Efficiency

Pumping unit and pump equipment is widely used with its shaky and durable characteristics,80% domestic wells use this equipment to exploit oil. But the problem of pumping wells system's low efficiency has not been solved well which is also seriously affect overall economic efficiency. According to statistics, the average system efficiency of pumping wells abroad is 32%, while only 25.96% of domestic. Therefore, how to greatly improve the system efficiency of pumping wells is urgent for major oil fields to ensure the development of crude oil production and improve the economic efficiency of oilfield development. Method to improve the system efficiency of pumping wells is built on the basis of a single factor analysis which can't comprehensively propose effective improvement measures. Especially the adjustment of oil solution, oil condition and distribution of pumping efficiency changed with the further development of oil fields. Therefore, from the system point of view, the study of the distribution of the efficiency of various parts from the ground to the underground and sensitive factors is the key to improve the efficiency of the pumping wells system, it also provide a theoretical basis for improving the efficiency of the pumping wells system, it is important for energy saving of oilfield.Pumping well system's energy transfer process is complex, it involved solid Mechanics, hydromechanics and production engineering and other disciplines which is a multi-physics coupling problem, so broken it down into the ground transmission system and the underground system to study. Established mathematical model of belt drive mechanism's efficiency calculation, mechanical model and finite element model of gear transmission, four-bar linkage, underground rod system, and pump through mechanical analysis. Formed numerical simulation method of subsystem of pumping wells and obtained the operating efficiency of the subsystems.Installed in the tester on motor output shaft, gear box input shaft, gear box output shaft and head hanging point of test well pumping unit which achieved admission sync of ground power transmission parameters of each node. Installed dynamometer on sucker of underground pump plunger's top and got pump dynamometer. Got variation of friction of wellhead packing boxes through test measurement and analysis which apply basis for quantitative calculation of the efficiency of rod. Got efficient distribution of ground drive subsystems and underground subsystems. Compared efficiency of the subsystems from test results and theoretical calculations and the deviation are all less than 10%, it have a good degree of agreement,so it proved that theoretical analysis is right and possible.Analyzed main factors of efficiency of the subsystems (stroke, strokes, load, balance, dynamic surface, pump diameter and gas content) based on the formed numerical simulation of efficiency calculation of each pumping wells' subsystem. Analyzed sensitivity of every factor affects the efficiency of each subsystem. Proposed key link and main measures to improve the efficiency of pumping wells system which provides a new way to improve the efficiency of the system.Obtained the distribution and variation of system efficiency by theoretical calculations and experimental research. Proposed critical path and the main parameters to improve efficiency for the lower efficiency of the system. The proposed improvements will enlighten to increase crude oil production and reduce production costs, and it has a certain relevance and practical value to improve the technological level of oilfield development and economic benefits.