基于斜面圆弧法的三维绕障轨道设计方法

Three-dimensional detouring well design method study based on inclined plane circular arc method

在复杂的钻井工况下,需要绕过一定障碍钻达目标点,要求设计的井眼轨道既有井斜角的变化,又有方位角的变化。运用传统的圆柱螺线法设计三维绕障井时,先设计水平面上的投影,再设计垂直剖面图,设计步骤繁琐,空间曲线复杂。将用于纠斜设计的斜面圆弧法运用于三维绕障井设计,且使井眼轨道上任一点在水平面上的投影距绕障中心的距离大于绕障半径,从而使斜面圆弧法设计绕障井成为可能。由于设计的井眼轨道仅为斜平面上的圆弧和直线,轨道形状简单,设计方便。施工中运用单一的造斜率进行钻进,不用频繁地调整造斜率或更换造斜工具,施工方便。

Under complicated drilling circumstances, detouring well is designed to detoure obstacles between wellhead and target, both deviation angle and azimuth angle are required to change to fulfill this kind of well design detouring well is desinged to detoure obstacles between wellhead and target, both deviation angle and azimuth angle are regaired to change to fulfill this kind of well design. On designing 3-D detouring well by using traditional cylinder helix method, projection on the horizon is designed first, then the vertical profile, the procedures of this method are complex and space curves are complicated. Three-dimensional Detouring well design based on the inclined plane circular arc method is discussed in this passage： by adding a constraint, that is, by making the distance between the detouring center and the horizontal projection point larger than the detouring radius, detouring well design based on inclined plane circular arc method becomes possible. As the designed well tracks are just arcs and straight lines, space curves of well track are simpli- fied and design becomes convenient. By using single build-up rate in the operation, build-up rate of tools no longer needs to be adjusted or deflecting tools no longer need to be replaced frequently, which greatly facilitate the operation. The method discussed in this passage enriches three-dimensional detouring well track design methods.