油井多层开采自动换层器设计分析

Design of Automatic Flow Control Valve for Commingled Production Well

为了克服油井多层合采时由于层间渗透率和压力差异而导致的层间相互制约与干扰问题,设计了油井多层开采自动换层器。该换层器设有2组独立的油流通道,根据相邻油层作用在活塞杆上的压力差异自动建立高压层产液通道并封闭低压层产液通道,实现高压层单层生产。换层器设定了换层压差阈值,根据活塞杆受力平衡原理,对换层压差阈值进行了设计分析与试验验证,设计值与试验值的误差小于0.10 MPa。设计分析与试验均指出:换层器能自动变换油流通道,可以实现高压层单层生产与多层轮换开采功能;换层压差阈值理论计算模型具有一定的合理性与正确性。该换层器可为解决油层合采时各层产液及含水率无法区分与计量的难题,以及不同油层间产能规律不同导致的油层间相互干扰问题提供技术手段。

In order to solve interlayer interaction and interference due to interlayer permeability and pressure difference in the commingled production well, an automatic flow control valve is designed. The flow control valve has two groups of independent oil flow channels, and it can automatically build a high-pressure layer fluid production channel based on pressure difference of adjacent oil reservoirs on the piston rod to achieve single-layer production under high pressure. A pressure differential threshold is set for the automatic flow control valve. Design analysis and test verification are conducted for the pressure differential threshold, and the error of design value and test value is lower than 0. 10 MPa . Design analysis and test results indicate that the automatic flow control valve can auto-matically change the oil flow channel to achieve single-layer production and multi-layer production under high pres-sure; the theoretical calculation model of pressure differential value has certain rationality and correctness. T he automatic flow control valve provides an effective technique to address the difficulty in differentiation and measurement of production fluid and water cut in reservoirs of the commingled production well and the interlayer interference arising from difference of production capacity between oil reservoirs.