Research On Rotation Steady Inclined Drilling System For Horizontal Extended Reach Wells

Large displacement horizontal well section can make the wellbore contact with more of the reservoir,improve the flow character of the reservoir and get larger drainage area,so as to improve the comprehensive recovery efficiency of single well of oil and gas.Sliding composite drilling technique was usually adopted in domestic,for the reason of the hole friction is big in the process of drilling,the extension of the horizontal section length is limited.Research on rotation steady inclined drilling system for large displacement horizontal well section is the only way.Based on the existing Modulation Rotary Steering drilling Tool(MRST)as the foundation,focus on the special working conditions of the large displacement horizontal well section drilling,qualitative and quantitative research for rotation steady inclined drilling system for large displacement horizontal well section.The control function is refined;three mud slurry flow distribution plate valves are designed in this system,and three-dimensional modeling software Solid Works is used to complete three valve designing.MATLAB is used to analysis the relationship between three disc valve opening size and rotation Angle with steady inclined tool actuator force,and three disc valve structure are further optimization designed.Stepper motor is designed to drive control valve,control rotational stability tools adjust deviation and azimuth in horizontal well section.Design different stepper motor operation curves and carries on the analysis comparison,respectively,Simulink is used to complete simulation,the most suitable control method of operation curve is analysis and determined.Natural gravity eccentric stabilized platform is designed to control central disc valve,provide the location torque to the control system,measurement,storage,control,transfer function and hardware are integrated in the stabilized platform.Through mechanical analysis,mechanics model is set up,Simulink is used to analysis eccentric gravity type natural stabilized platform under different working loading conditions,and the orthogonal experiment is used to complete the optimal design of stabilized platform.The internal structure of overall drilling system is concise,either realized the stabilization in the process of drilling in large displacement horizontal well section or also can realize the adjustment of the hole deviation and azimuth.This paper established the foundation to rotation steady inclined drilling system for large displacement horizontal well section.