The Application And Research Of Dynamometer Card In The Oilfield Single Well Metering System

Production of the oil well liquid volume measurement is the basis of oilfield enterprises production management to improve crude oil liquid producing capacity, reduce investment, saving cost. It has an important significance. Power diagram method oil measurement technology although without laying of pipelines and equipment low cost of engineering investment, easy maintenance, in many aspects have its unique advantages, however precision oil of this measurement method fails to meet the needs of oilfield actual needs on the ground. This paper to Hua Qing oilfield with low permeability and extra low permeability oil production situation as the background?for oil and gas oil ratio?not continuous oil, oil production fluctuation problem, of merit chart measurement of oil well liquid producing capacity were analyzed and studied. Main work is as follows:Rod pumping system as the research object, established vibration model and wave equation and of model and wave equation were analysis?according to the surface dynamometer card prediction of downhole pump dynamometer card. Then, the five point average curvature method, the pump dynamometer card was normalized, determine the valve opening and closing position?calculate the plunger effective stroke.Tubing in the mixture is compressibility?calculated according to the effective stroke of the piston theory of underground fluid production rate is not equal to wellhead actual liquid production, through the analysis of the property parameters of the downhole mixture, calculation of discharge pressure under the condition of mixture volume coefficient and converted into a wellhead actual liquid producing capacity.Using Visual Basic programming language to develop a set of indicator diagram of oil quantity software, and in Huaqing oilfield of 6 wells, for example, indicator diagram measurement results and actual measured results were compared with that of the test. The test results show that: normal diagram of oil wells, the diagram of the gauge error is small, achieve ABSTRACT oilfield single well metering. For special types of diagram?yield error is bigger, need to diagram yield was modified, and will be able to meet the Huaqing low permeability oilfield single well metering accuracy.