ABSTRACT:Spatial arc , as a typical model to plan a 3Dwell path ,is widely applied in planning the path of multiple tar2gets well ,branch well ,sidetrack well and in rectifying the path ofdirectional well , horizontal well and extended2reach well. The
problem becomes even more complicated for two reasons :A 3Dwell path is usually planned and calculated in the vertical plotand the horizontal plot ;on the other hand the spatial arc is not asimple curve as arcs in these two plots. As a result ,approximationformulae have been used to calculate a spatial arc. According to
the plan demand of well path and the feature of spatial arc ,a se2ries of formulae ,including coordinate ,inclination ,azimuth ,rate ofinclination change ,rate of azimuth change and tool face angle ,a represented in this paper for spatial arc model. All of these formu2 lae ,testified by many examples ,provided such exact solutions ab2 stractly that they lay a foundation for the further application of spatial arc model and the path plan improvement of 3D wells.
空间圆弧作为一种典型的井眼轨道模型 ,广泛应用于多目标井、分支井、侧钻井等三维井眼轨道设计 ,以及定向井、水平井和大位移井的调整轨道设计。由于三维井眼轨道的设计与计算通常都是在垂直剖面图和水平投影图上进行的 ,而空间圆弧在这两个平面上又都不是像圆弧那样的简单的曲线形式 ,所以增加了问题的复杂性。由于这种原因 ,目前对空间圆弧轨道的计算多采用近似公式。文章结合井眼轨道的设计要求和空间圆弧的特点 ,提出了空间圆弧轨道上的坐标、井斜角、方位角、井斜变化率、方位变化率和装置角的计算公式。这些计算公式在理论上是精确解 ,具有普遍适用性 ,从而为空间圆弧轨道模型的进一步应用和三维井眼轨道设计奠定了基础。所有公式都通过算例进行了验证。
[ 此贴被笑韵在2008-01-08 16:41重新编辑 ]
