定向井斜向器座放方位最优化设计

OPTIMIZATION DESIGN OF MULESHOE ORIENTATION ANGLE IN DIRECTIONAL WELL

利用斜向器开窗侧钻是最主要的侧钻方式之一。现场施工中常用三种方法：①斜向器座放在窗口和靶点的设计方位线方向；②根据设计井眼轨迹的井斜方位变化趋势和斜向器对井斜方位的影响关系，确定斜向器应座放在哪一象限内；③斜向器始终座放在井眼高边，若设计轨迹为降方位趋势，则座放在高边的左边，否则，座放在高边的右边。研究证明，这三种方法都不能准确地确定出斜向器应当座放在一个准确具体的角度，和施工者的经验有关，不是最优方法。文章把非线性最优化理论引入到定向井斜向器座放方位的最优化计算中，建立了非线性规划方程组，并应用序列无约束极小化混合法（ＳＵＭＴ混合法）求解，解决了定向井斜向器开窗侧钻问题。该方法已经利用 Ｖｉｓｕａｌ Ｂａｓｉｃ语言编制成为一个用户界面非常友好的软件 ＷＳＳ，操作简单，使用方便。

Sidetracking by the aid of a muleshoe is one of the most important sidetracking ways. There are three operation methods on the spot, i. e. (1) the muleshoe is set on the designed orientation line from kickoff point to target point; (2) which quadrant should be located in by the muleshoe is dependent upon the change trend of inclination orientation of the designed hole track and the effect of the muleshoe on the inclination orientation; and (3) the muleshoe is always set on the high side of borehole; if the inclination orientation of the designed hole track is on a decreasing trend, the muleshoe is set on the left of the high side; otherwise, on the right of the high side. Through research it is proved that the three methods aren't the optimization ones, by which an exact muleshoe setting angle can not be obtained and its being obtained is related to the experience of the operators. In the paper, the non-linear optimization theory is introduced into the optimal calculation of the muleshoe orientation angle in directional well; and the non-linear programming equations are founded and solved by SUMT method, thus settling the question of the sidetracking by the muleshoe in directional well. The WSS software with a good user interface has been programmed for these method by use of Visual Basic and it is very easy to be operated and used.