实施垂直钻井中的主动纠斜需要解决诸如井斜动态测量、纠斜机构动力的获取和可靠控制等问题。通过滤除迭加在重力加速度计上的振动信号,以及对由于加速度计随钻杆转动产生的离心力带来的信号失真进行补偿,可有效解决井斜实时控制中的井斜测量问题;通过对液控导向机构的理论建模和动力学仿真,确定了可适用于井下恶劣工况的导向纠斜装置的动力机构,并且井下超常环境压力还可使这种机构具有更好的响应性能;返程泥浆对旋转中的导向活套的冲击将会产生阻碍活套随钻杆转动的反向扭拒,从而可使活套与钻杆之间产生转差,便于导向机构从钻杆的转动中获得足够的动力,用计算流体力学软件给出具体的结果。
For active anti-deviation in vertical drilling, such problems as dynamic measurement of well inclination, obtainment and reliable control of power of steerable anti-deviation mechanism need to be resolved first. By filtering vibration signals added to gravity accelerometer and compensating signal distortion due to centrifugal force generated when accelerometer rotates following drill stem can the inclination measurement problem be resolved effectively in real-time control of vertical drilling. Through theoretical modelling and dynamic simulation of hydraulic controlled steerable mechanism, the power mechanism of anti-deviation device that works well in worse conditions is determined, and supernormal environmental pressure down in the well can lead to good response of the mechanism. Shock from backward mud on rotating sleeve can generate opposite torque which hinders the sleeve rotation following the drill stem. Consequently rotary difference can be generated between sleeve and drill stem, which creates conditions for steerable mechanism to gain enough power from the rotation of drill stem. Concrete results are produced by means of fluid dynamics calculation software.