超短半径水平井导向筛管结构优化设计

导向筛管是超短半径水平井柔性钻具的重要组成部分,其结构尺寸的合理性直接影响钻具的造斜能力。基于导向筛管与井眼曲率相匹配的条件,采用贝塞尔曲线拟合导向筛管运动轨迹方程,得到导向筛管单节最大长度。在满足强度和弯曲刚度条件基础上,对各结构参数进行了优化。采用有限单元法,考虑导向筛管的材料非线性及横缝之间的接触非线性,建立了导向筛管有限元模型,并给出了求解策略。对优化后的单节导向筛管进行力学分析,验证了导向筛管结构优化设计的合理性。研究成果为导向筛管开槽结构设计提供理论参考,为超短半径水平井的成功钻进提供必要的工具支持。

Structural Optimization Design of Ultra-short Radius Horizontal Well Guiding Screen Tube

The guiding screen tube is an important part of the ultra-short radius horizontal well flexible drilling tool, and the rationality of the structure size directly affects the drilling ability of the drilling tool. Based on the condition that the guiding screen tube matches the borehole curvature, the maximum length of a single section of the guiding screen tube was obtained by fitting the motion trajectory equation of the guide screen tube with Bezier curve. The structural parameters were optimized based on the strength and bending stiffness conditions. The finite element model of the guiding screen tube was established by using the finite element method and considering the material nonlinearity of the guiding screen tube and the contact nonlinearity between the transverse joints, and the solving strategy of finite element model was given. The rationality of the structure optimization design of guiding screen tube was verified through the mechanical analysis of the optimized single section guiding screen tube. The research results provide reference for the design of slotted structure of guiding screen tube.