Torsional Vibrations and Nonlinear Dynamic Characteristics of Drill Strings and Stick-Slip Reduction Mechanism

Torsional stick–slip vibrations easily occur when the drill bit encounters a hard or a hard-soft staggered formation during drilling process. Moreover, serious stick–slip vibrations of the drill string is the main factor leading to low drilling efficiency or even causing the downhole tools failure. Therefore, establishing the stick–slip theoretical model, which is more consistent with the actual field conditions, is the key point for new drilling technology. Based on this, a new torsional vibration tool is proposed in this paper, then the multidegree-of-freedom torsional vibrations model and nonlinear dynamic model of the drill string are established. Combined with the actual working conditions in the drilling process, the stick–slip reduction mechanism of the drill string is studied. The research results show that the higher rotational speed of the top drive, smaller viscous damping of the drill bit, and smaller WOB (weight on bit) will prevent the stick–slip vibration to happen. Moreover, the new torsional vibration tool has excellent stick–slip reduction effect. The research results and the model established in this paper can provide important references for reducing the stick–slip vibrations of the drill string and improving the rock-breaking efficiency.

[1]  Changfu Yuan,et al.  The wear analysis model and rock-breaking mechanism of a new embedded polycrystalline diamond compact , 2017 .

[2]  Zhi Yang,et al.  Vibration analysis of new drill string system with hydro-oscillator in horizontal well , 2016 .

[3]  K. Bybee.  A Stick/Slip Analysis Based on Rock/Bit Interaction , 2000 .

[4]  Jialin Tian,et al.  Mathematical Modeling and Analysis of Drill String Longitudinal Vibration with Lateral Inertia Effect , 2016 .

[5]  Guang Meng,et al.  Multiple regenerative effects in cutting process and nonlinear oscillations , 2014 .

[6]  Liu Gang,et al.  The vibration analysis model of pipeline under the action of gas pressure pulsation coupling , 2016 .

[7]  Robin Tucker,et al.  On the modelling of Coulomb friction , 1999 .

[8]  Lin Yang,et al.  Vibration characteristics analysis and experimental study of horizontal drill string with wellbore random friction force , 2017 .

[9]  D. A. Castello,et al.  Stochastic analysis of torsional drill-string vibrations considering the passage from a soft to a harder rock layer , 2017 .

[10]  Lin Yang,et al.  Vibration characteristics analysis and experimental study of new drilling oscillator , 2016 .

[11]  B. Balachandran,et al.  A Mechanics Based Model for Study of Dynamics of Milling Operations , 2000 .

[12]  B. Balachandran,et al.  State-Dependent Delay Influenced Drill-String Oscillations and Stability Analysis , 2014 .

[13]  Emmanuel M Detournay,et al.  A simplified model to explore the root cause of stick–slip vibrations in drilling systems with drag bits , 2007 .

[14]  Lin Yang,et al.  Working mechanism and rock-breaking characteristics of coring drill bit , 2018 .

[15]  Liming Dai,et al.  Kinetic characteristics analysis of a new torsional oscillator based on impulse response , 2018 .

[16]  Lin Yang,et al.  Dynamic characteristics and test analysis of a new drilling downhole tool with anti-stick-slip features , 2018 .

[17]  N. Challamel,et al.  A Stick-slip Analysis Based on Rock/Bit Interaction: Theoretical and Experimental Contribution , 2000 .

[18]  Zhi Yang,et al.  Bottomhole Model and Rock-Breaking Features Study of New Drill Bit with Swirling-Cutting Motion , 2016 .

[19]  Arifin Purwanto,et al.  Active vibration damper improves performance and reduces drilling costs , 2008 .

[20]  Lin Yang,et al.  Rock-breaking analysis model of new drill bit with tornado-like bottomhole model , 2015 .

[21]  E.M. Navarro-Lopez,et al.  Sliding-mode control of a multi-DOF oilwell drillstring with stick-slip oscillations , 2007, 2007 American Control Conference.

[22]  L. Fradet,et al.  Geometrical variations in white and gray matter affect the biomechanics of spinal cord injuries more than the arachnoid space , 2016 .

[23]  Balakumar Balachandran,et al.  Drill-String Dynamics: Reduced-Order Models and Experimental Studies , 2011 .

[24]  Marian Wiercigroch,et al.  Experimental studies of forward and backward whirls of drill-string , 2018 .

[25]  Guang Meng,et al.  Coupled axial-torsional dynamics in rotary drilling with state-dependent delay: stability and control , 2014 .

[26]  Krishnan Nandakumar,et al.  Stability analysis of a state dependent delayed, coupled two DOF model of drill-stringvibration , 2013 .

[27]  A. Kyllingstad,et al.  A study of slip/stick motion of the bit , 1988 .

[28]  D. R. Pavone,et al.  Application of High Sampling Rate Downhole Measurements for Analysis and Cure of Stick-Slip in Drilling , 1994 .

[29]  Lin Yang,et al.  The Wear Analysis Model of Drill Bit Cutting Element with Torsion Vibration , 2015 .

[30]  Yehia A. Khulief,et al.  Vibration analysis of drillstrings with self-excited stick–slip oscillations , 2007 .

[31]  Jan Dirk Jansen,et al.  Active damping of self-excited torsional vibrations in oil well drillstrings , 1995 .