中文摘要：

井眼轨迹控制工具是随钻实时完成导向功能的一种导向式钻井工具.在复杂工况下，主轴承受钻压、扭矩和偏置机构作用力等，十分复杂.在课题组前期研究的基础上，对样机主轴的力学行为开展了进一步的研究，在建立主轴静力学模型的基础上，分析了工具外壳刚度、偏置机构安装位置等因素对主轴力学行为与造斜能力的影响规律.研究发现，主轴下端偏转角、偏心机构作用力和最大截面弯矩会随着偏心位移增加呈线性增加；随着外壳刚度的增加和偏置机构安装的位置与上支撑轴承之间距离的增加，工具造斜能力也会增强；通过分析偏置机构安装位置和外壳刚度对主轴力学行为的影响规律发现，随着外壳刚度的增大和偏置机构安装位置与上支撑轴承之间距离的增大，主轴最大截面弯矩也会增大.最后，给出了最佳的外壳刚度与偏置机构安装位置建议.

英文摘要：

The wellbore trajectory control tool is a sort of guiding drilling tool to achieve the orientation function while drilling.Under complex conditions,the spindle is under the actions of the bit pressure,the torque,the force of biasing mechanism and so on.This paper studies the mechanical behavior of the prototype spindle.A spindle mechanical model is established.With the model,the in fluences of the housing stffness and the position of the eccentric mechanism of the spindle on the mechanical behavior and the deflecting capacity are analyzed.The data analysis shows that the deflection angle of the lower end of the principal axis,theforce of the biasing mechanism and the maximum bending moment will increase linearly with the eccentric displacement of the eccentric ring.With the increase of the housing stiffness and the axial bearing distancefrom the mounting position of the biasing mechanism,the tool deflecting capacity will be enhanced and themaximum bending moment of the spindle will increase.It is shown that,we have selected the most suitable house stiffness and the mounting position of the biasing mechanism,which would serve as a reference for the spindle design and the improvement of the deflecting capacity of the wellbore trajectory control tool.