Horizontal well can be considered as a special case of directional wells, but the target window of a horizontal well is not included in the target area of the directional well. In fact, the target window of the horizontal well is in conflict with the target area of the directional well using the current well-design method. The basis for the unitization of the target area and the target widow is the redefinition of the relationship between the directional-horizontal well borehole axis and the target plane, namely the target plane should always be vertical to the borehole axis, and the target area in the target plane should vary with the increase of the inclination angle, gradually changing from a circular shape for a vertical well to a rectangle or oval shape for a horizontal well. In this paper, mathematical models of the target area with oval and rounded rectangle shapes were es-tablished respectively, and calculation software was formulated for mapping the safe boundary of the elliptic cone and rounded corner pyramid in the target area. The results show that the target plane should be perpendicular to the borehole axis, and the transition of the vertical well target area to the horizontal well target window along with the inclination angle is one of the ef-fective methods to resolve the conflict.%作为定向井特例的水平井的靶窗不包含在定向井的靶区范围内,定向井的靶区与水平井的靶窗相冲突.分析定向井的靶区与水平井的靶窗的特征,认为统一靶区的基础是重新确立定向井与水平井的井眼轴线与靶区平面的关系,即靶区平面应该始终与井眼轴线垂直;平面内的靶区应该随井斜角的增加逐渐由直井的圆面变成水平井的矩形或椭圆形.分别建立椭圆形和圆角矩形靶区渐变的数学模型,编写计算软件,绘制安全椭圆锥和圆角棱锥.结果表明,靶区平面应该为与井眼轴线垂直的平面,直井靶区随井斜角过渡到水平井靶窗是解决这一冲突的有效方法.
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