全旋转内置式可控弯接头运动特性

为准确了解钻井过程中导向钻井工具可控弯接头的井下运动规律,根据空间机构理论,建立了全旋转内置式可控弯接头的运动模型,采用Matlab进行模拟仿真,分析了不同工具角、不同工具面角以及不同工作状态下系统的运动规律,并通过Solidworks三维仿真验证模型的正确性。通过仿真得出了关键部件内偏心环、外偏心环、钻头的角速度和位移等运动学基本参数,揭示了可控弯接头的运动特征,研究了转速、偏心距与钻头运动轨迹的关系,求得了系统中各参数随时间变化的规律。研究结果表明,随着两个伺服电机转动角速度的变化,工具角调节速度和调节加速度呈余弦规律连续变化。研究结果为全旋转内置式可控弯接头的井眼轨迹控制提供了理论依据。

The kinematical characteristics of the full rotary built-in variable angle bent sub

In order to accurately understand the downhole motion laws of the variable angel bent sub of steering drilling tool in the process of drilling, the kinematics model of the full rotary built-in variable angle bent sub was established according to the theory of spatial mechanism, and its accuracy was verified by means of the Solidworks 3D simulation. Then, motion laws of the system under different tool angles, tool face angles and working states were analyzed. In this model, the Matlab is used for simulation. The basic kinematical parameters of key parts are obtained, e.g. inner eccentric ring, outer eccentric ring and bit’s angular velocity and displacement. The kinematical characteristics of variable angle bent sub is revealed, the relationships between rotation speed and excentricity and bit’s motion trajectory, and the change laws of system parameters over the time are concluded, so as to provide the theoretical basis for the borehole trajectory control of full rotary built-in variable angle bent sub.