Research On The Working Mechanism And Viscosity Reduction Characteristics Of A New Type Of Rotary Vibration Tool

With the development of oil and gas fields gradually to the deep strata and deep sea and other complex hard stratum development,the stick-slip vibration phenomenon of bit seriously affects the drilling rate and drilling tool life.A large number of field experience have revealed the validity of torque impactor which can control the stick-slip oscillate.Based on the previous research,to more effectively inhibit or reduce the stick-slip vibration of PDC bit,a new type of rotary vibration tool is designed.Through the research of kinematics and dynamics of the tool,the working mechanism and the stick-slip reduction characteristic of the tool are studied by theoretical derivation,numerical simulation,dynamic simulation and so on.The main contents and achievements of this paper include:(1)This paper analyzes the design principle and research status of the internal and external torsional impactor structure and analyzes its working performance in depth,investigates the present situation of the stick-slip vibration of the drill string,analyzes the existing stick-slip vibration suppression method.Based on the design concept of downhole tool in rotary drilling,a new type of rotary vibration tool is designed,and the working principle of the tool and the design basis of the important structure of the study is analyzed.(2)Researches on the working mechanism of the new rotary vibration tool are taken into account.Through the theoretical derivation,the flow distribution model of the new rotary vibration tool inlet is studied and the important contour curve equation of eccentric annular anvil and drive shaft is studied.The angular displacement and angular velocity analysis model of the eccentric annular anvil and the drive shaft are established,and creates a dynamic calculation model of the impact torque of the torsion impact.Based on the above research,the impact torque of the new rotary vibration tool and the angular velocity and the angular displacement curve of the torsion impact subassembly are proposed under different flow rates.(3)The kinematic simulation of the new rotary vibration tool was carried out by ADAMS software.The angular velocity curve and the impulse response curve of the drive shaft and the eccentric annular anvil were obtained.(4)The vibration model of the tool is established,and the vibration characteristics of the vibration tool are analyzed.Based on the mechanism of single-degree-of-freedom stick-slip vibration and combined with Karnopp friction model,the rock breaking model of the new rotary vibration drilling tool is established,and the effect of reducing stick-slip of the tool is studied.Using the numerical simulation method to obtain the stick-slip reduction curve of the new rotary vibration tool under different flow rates,different drilling depths,different WOB different upper driving torque under normal drilling tools,the vibration characteristics of the rotating tool stick-slip reduction curve,as well as the same conditions under the new rotary vibration tool and PID control stick-slip reduction curve.Through the research on the working mechanism and stick-slip reduction of the new rotary vibration tool,it has certain reference value for suppressing or reducing the stick-slip vibration of the PDC bit and the research and use of the stick-slip reduction tool.