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在水平钻井中，井身曲率较常规定向井井身曲率大。若用直梁单元来分析钻柱的受力变形值，为了确保计算精度，其单元划分势必不能过大，因而单元数必然增多、计算时间增长，影响解题效率和推广应用。根据有限元法的基本原理，研究了适合于水平井钻柱受力变形分析的圆弧曲梁单元及刚度矩阵＊＊，并编制了相应的计算机程序。经典型例题和水平井钻柱力学分析计算结果表明：对于同一结构，在计算精度不变的条件下，曲梁单元少于直梁单元，且计算时间缩短，这对于曲率较大的水平井钻柱进行非线性力学分析尤为重要。因此，对曲率较大的钻柱进行力学分析时，完全可以用曲梁单元取代直梁单元来降低计算时间。
In horizontal drilling, the curvature of the wellbore is larger than that of conventional directional wellbores. If the straight beam element is used to analyze the force and deformation value of the drill string, in order to ensure the accuracy of calculation, the unit division must not be too large, so the unit number will inevitably increase and the calculation time will increase, which will affect the problem solving efficiency and popularization and application. According to the basic principle of the finite element method, the circular curved beam element and stiffness matrix * * which is suitable for the analysis of stress and deformation of horizontal wellbore are studied, and the corresponding computer program is compiled. The classical example and the mechanics analysis results of the horizontal well drill string show that for the same structure, the curved beam unit is less than the straight beam unit and the calculation time is shortened under the condition of the same precision, Column for nonlinear mechanical analysis is particularly important. Therefore, the mechanical analysis of the larger curvature of the drill string, it is entirely possible to replace the straight beam unit bent beam unit to reduce the calculation time.