基于示功图的油井含水率实时计算模型

Real Time Calculation Model of Water Cut in Oil Well Based on Indicator Diagram

针对目前原油含水率测量主要为离线人工测量法,存在成本高、周期长、耗时费力、实时性差、无法实现智能化测量的问题,通过对示功图载荷斜率-时间关系曲线的变化规律进行分析,研究泵阀开闭点的提取方法,确定了示功图上下冲程载荷差,并结合井筒多相管流压力分布计算相关式,推导建立了基于示功图的油井含水率计算模型,并利用C#语言编制了油井含水率计算软件。以现场某油田的15口油井为实例进行模型应用检验,计算得出的含水率与实测含水率的平均相对误差为7.42%,在工程允许的误差范围内,表明该模型具备实用性,能够为现场提供理论与技术支持。同时,基于油田现场实时采集的示功图数据,可实现油井含水率的实时计算,提高了油田信息化与智能化管理水平,有利于油田降低生产管理成本,提高生产效率与效益。

At present, the measurement of water cut in crude oil is mainly off-line manual measurement, which has the problems of high cost, long cycle, time-consuming and poor real-time performance, and it is unable to realize real-time, economic, efficient and intelligent measurement. In this paper, by analyzing the change law of load slope and time relationship curve of indicator diagram, the extraction method of pump valve opening and closing points was studied, the load difference between the up and down stroke of indicator diagram was determined, and combined with the calculation formula of wellbore multiphase pipe flow pressure distribution, oil well water cut calculation model based on indicator diagram was deduced and established, and oil well water cut calculation software was compiled with C#. Taking 15 oil wells in an oil field as an example, the average relative error between the calculated water cut and the measured water cut was 7.42%, which showed that the model was practical and could provide theoretical and technical support for the field. At the same time, based on the indicator diagram data collected in real time, the real-time calculation of water cut in oil wells can be realized, and the informatization and intelligent management level of the oilfield can be improved, which is conducive to reducing the production management cost and improving the production efficiency and benefit.