防碰分离系数算法优选与邻井相对位置测量误差计算

Optimization of Anti-collision Separation Factor Algorithm and Calculation of Adjacent Well Relative Position Measurement Error

在丛式井和加密井的定向钻井工程中,科学地评估正钻井与相邻已钻井的井眼碰撞风险具有十分重要的意义。目前,常用于评估井眼碰撞风险的分离系数具有多种计算方法。在分析分离系数常用计算方法局限性基础上,通过协方差矩阵的合成,建立了考虑井径影响的邻井相对位置测量误差计算模型,提出了基于邻井相对位置测量误差计算的分离系数算法优选方法;通过实例计算,分析了相同条件下常用分离系数(垂足分离系数和定向分离系数)计算结果的差异。同时实例计算结果表明,文章提出的分离系数算法优选方法可以优选出符合实际情况的分离系数,为定向井工程实施防碰作业提供更为科学的依据具有重要的应用价值。

In the directional drilling engineering of cluster wells and infill wells,it is of great significance to scientifically evaluate the collision risk between a wellbore being drilled and an adjacent existing wellbore. At present,there are multiple methods for calculating the separation factor commonly used to evaluate the risk of borehole collision. This paper introduces the principle of the calculation methods of separation factor and analyzes the limitation of these methods. By combining the covariance matrix and considering the influence of borehole diameter,the measurement error calculation model of adjacent well relative position is established,and the optimized method of separation factor algorithm based on the calculation and visualization of adjacent well relative position measurement error is proposed. The difference of the calculation results of the common separation factors( Pedal Separation Factor and Oriented Separation Factor) under the same condition is analyzed through the example calculation. At the same time,the calculation results of the example show that the separation factor in line with the actual situation can be optimized through the optimized method proposed in this paper,which provides a more scientific basis for the implementation of anti-collision operation in directional drilling and has important application value.