Stick-slip vibration suppression method and device, equipment, storage medium and program product

Abstract

The invention discloses a stick-slip vibration suppression method, device and equipment, a storage medium and a program product, and relates to the technical field of oil and gas resource exploration and development. The method comprises the steps that on the basis of engineering parameters of a target well, angular displacement of each mass block of the target well at multiple moments is calculated through a horizontal well drill string stick-slip vibration analysis model, and the target well is a long horizontal well to be drilled; performing stick-slip vibration grade evaluation on each mass block of the target well based on the angular displacement to obtain a stick-slip vibration grade of each mass block of the target well; and on the basis of a stick-slip vibration suppression strategy corresponding to the stick-slip vibration rating, tubular column stick-slip vibration of each mass block of the target well is suppressed. By means of the method and device, the technical problem that stick-slip vibration of a drill string system in the long horizontal drilling process cannot be effectively relieved or restrained in the related technology is solved.

Description

Technical Field

[0001] This invention relates to the field of oil and gas resource exploration and development technology, and in particular to a method, apparatus, equipment, storage medium and program product for suppressing stick-slip vibration. Background Technology

[0002] With advancements in deep well drilling technology, drilling depths are increasing, and the stick-slip phenomenon in the drill string is becoming more prominent, gradually becoming a significant factor restricting drilling efficiency and quality. Accidents caused by stick-slip vibration, such as accelerated failure of the drill bit and bottom hole tools, and drill pipe wear and breakage, seriously affect drilling efficiency, drilling safety, and drilling costs. Therefore, mitigating or suppressing stick-slip vibration in the drill string system is a pressing technical problem that needs to be solved. Summary of the Invention

[0003] This invention provides a method, apparatus, equipment, storage medium, and program product for suppressing stick-slip vibration, which can solve the technical problem in the prior art that it is impossible to effectively reduce or suppress stick-slip vibration of the drill string system during long horizontal drilling.

[0004] To achieve the above objectives, the present invention provides the following technical solution:

[0005] In a first aspect, embodiments of the present invention provide a method for suppressing stick-slip vibration, the method comprising:

[0006] Based on the engineering parameters of the target well, the angular displacement of each mass block of the target well at multiple times is calculated using the stick-slip vibration analysis model of the horizontal well drill string. The target well is a long horizontal well to be drilled.

[0007] Based on the angular displacement, the stick-slip vibration level of each mass block of the target well is evaluated to obtain the stick-slip vibration rating of each mass block of the target well.

[0008] Based on the stick-slip vibration suppression strategy corresponding to the stick-slip vibration rating, the stick-slip vibration of the tubing in each mass block of the target well is suppressed.

[0009] Secondly, embodiments of the present invention provide a stick-slip vibration suppression device, the device comprising:

[0010] The calculation module is configured to calculate the angular displacement of each mass block of the target well at multiple times based on the engineering parameters of the target well and through the stick-slip vibration analysis model of the horizontal well drill string. The target well is a long horizontal well to be drilled.

[0011] The rating module is configured to evaluate the stick-slip vibration level of each mass block of the target well based on the angular displacement, and obtain the stick-slip vibration rating of each mass block of the target well.

[0012] The parameter adjustment module is configured to suppress the stick-slip vibration of the tubing in each mass block of the target well based on the stick-slip vibration suppression strategy corresponding to the stick-slip vibration rating.

[0013] Thirdly, embodiments of the present invention also provide an electronic device, including: a memory and a processor; the processor is configured to read and execute a computer program stored in the memory to implement the steps of the aforementioned stick-slip vibration suppression method.

[0014] Fourthly, embodiments of the present invention also provide a computer storage medium storing computer-executable instructions, which, when executed, implement the steps of the aforementioned stick-slip vibration suppression method.

[0015] Fifthly, embodiments of the present invention also provide a computer program product, including a computer program / instruction, which, when executed by a processor, implements the steps of the aforementioned stick-slip vibration suppression method.

[0016] The beneficial effects of the technical solutions provided by the embodiments of the present invention include:

[0017] This invention enables precise determination of the stick-slip vibration of the drill string under oil-based drilling fluid conditions, as different stick-slip vibration ratings exhibit different color distributions. It also allows for the determination of the parameter range corresponding to a stick-slip vibration rating less than or equal to the intermediate level. This enables targeted optimization of engineering parameters and drill string assembly for the target well, thereby suppressing stick-slip vibration of the drill string. This invention solves the technical problem in related technologies that cannot effectively mitigate or suppress stick-slip vibration of the drill string system during long horizontal drilling. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic flowchart of an embodiment of the stick-slip vibration suppression method of the present invention;

[0020] Figure 2 This is a schematic diagram of the target wellbore structure of the present invention;

[0021] Figure 3 This is a schematic diagram showing the angular displacement, angular velocity, angular acceleration, and drill torque of the drill bit at multiple moments under different rotary table speeds;

[0022] Figure 4This is a schematic diagram showing the angular displacement, angular velocity, angular acceleration, and drill bit torque at multiple moments under different drilling pressures.

[0023] Figure 5 This is a schematic diagram of the stick-slip vibration analysis model for horizontal well drill strings according to the present invention;

[0024] Figure 6a This is a schematic diagram of the angular displacement of the drill bit at multiple moments;

[0025] Figure 6b This is a schematic diagram showing the angular velocity of the drill bit at multiple moments.

[0026] Figure 6c This is a schematic diagram of the angular acceleration of the drill bit at multiple moments;

[0027] Figure 6d This is a schematic diagram of the drill bit torque at multiple moments.

[0028] Figure 7a A schematic diagram showing the influence of turntable rotation speed on the evaluation index value of stick-slip vibration.

[0029] Figure 7b This is a schematic diagram illustrating the impact of drill pressure on the evaluation index values ​​of stick-slip vibration.

[0030] Figure 7c A schematic diagram illustrating the influence of horizontal segment length on the evaluation index value of stick-slip vibration.

[0031] Figure 7d This is a schematic diagram illustrating the influence of drill collar length on the evaluation index value of stick-slip vibration.

[0032] Figure 8 This is a schematic diagram of the stick-slip vibration level diagram of the first embodiment;

[0033] Figure 9 This is a schematic diagram of the stick-slip vibration level diagram of the second embodiment;

[0034] Figure 10 for Figure 1 A detailed flowchart of step S10;

[0035] Figure 11 for Figure 1 A detailed flowchart of step S20;

[0036] Figure 12 This is a schematic diagram of the functional modules of an embodiment of the stick-slip vibration suppression device of the present invention;

[0037] Figure 13 This is a schematic diagram of the structure of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0040] In a first aspect, embodiments of the present invention provide a method for suppressing stick-slip vibration.

[0041] In one embodiment, reference is made to Figure 1 , Figure 1 This is a schematic flowchart of an embodiment of the stick-slip vibration suppression method of the present invention. Figure 1 As shown, the stick-slip vibration suppression method includes:

[0042] Step S10: Based on the engineering parameters of the target well, the angular displacement of each mass block of the target well at multiple times is calculated using the horizontal well drill string stick-slip vibration analysis model. The target well is a long horizontal well to be drilled.

[0043] In some specific embodiments, reference is made to Figure 10 , Figure 10 for Figure 1 A detailed flowchart of step S10. (See attached diagram.) Figure 10 As shown, step S10 includes:

[0044] Step S101: For any mass block of the target well, calculate the frictional torque and non-Newtonian rheological damping of the mass block at the current moment based on the engineering parameters and the initial angular displacement of the mass block at the current moment.

[0045] In some specific embodiments, step S101 includes:

[0046] Substituting the engineering parameters and the initial angular displacement of the mass block at the current moment into the first preset formula, the non-Newtonian rheological damping of the mass block at the current moment is calculated;

[0047] Substituting the non-Newtonian rheological damping, the engineering parameters, and the initial angular displacement of the mass block at the current moment into the second preset formula, the frictional torque of the mass block at the current moment is calculated.

[0048] The first preset formula is as follows:

[0049]

[0050] In the formula, CHb A represents the non-Newtonian rheological damping between mass block b and the drilling fluid. f τ represents the contact area between the fluid and the drill string. Hy This represents the yield stress in a non-Newtonian fluid model. denoted by angular displacement of mass block b, k represents fluid consistency coefficient, n represents flowability index, V represents rotary table speed, and Δ represents mud thickness.

[0051] The second preset formula is as follows:

[0052]

[0053] In the formula, T hb T represents the frictional torque between mass block b and the formation; r This represents the torque transmitted from the drill string to the mass block b. Let T represent the angular velocity of mass b, Δv represent the threshold of the zero velocity interval, and T represent the angular velocity of mass b. sb T represents the maximum static friction torque. sb =μ sb *WOB*R b μ sb R represents the maximum static friction coefficient, WOB represents the drilling pressure, and R represents the drilling pressure. b T represents the radius of mass block b; cb T represents the sliding friction torque. cb =μ cb *WOB*R b μ cb ξ represents the coefficient of sliding friction; ξ∈[0,1] is an empirical constant and defines the rate of decrease of frictional torque.

[0054] In this embodiment, the engineering parameters include: shear modulus of steel, drill string outer diameter, drill string inner diameter, drill string length, drill string damping coefficient per unit length, steel density, rotary table speed, static friction coefficient, sliding friction coefficient, drilling pressure, radius of each mass block, yield stress, flowability index, fluid consistency coefficient, mud thickness, contact area between fluid and drill string, and rotary table speed.

[0055] The mass blocks of the target well include: non-horizontal drill pipe, horizontal drill pipe, weighted drill pipe, drill collars, and drill bit.

[0056] The target well is a long horizontal well to be drilled. For example, the wellbore structure of the target well is as follows: Figure 2 As shown, Figure 2 In the second section, the artificial bottom of the target well is 4536m; in the third section, the artificial bottom is 6011.37m.

[0057] The target well drilling tool assembly is shown in Table 1.

[0058] Table 1

[0059]

[0060] The engineering parameters of the target well are shown in Table 2.

[0061] Table 2

[0062]

[0063] For the drill bit of the target well, the engineering parameters and the initial angular displacement of the drill bit at the current moment are substituted into the first preset formula. The non-Newtonian rheological damping of the drill bit at the current moment is calculated. The non-Newtonian rheological damping of the drill bit is the non-Newtonian rheological damping between the drill bit and the drilling fluid. Wherein, τ Hy =0.511θ3, n = 3.26lg[(θ 200 -θ3) / (θ 100 -θ3)],k=0.511(θ 100 -θ3) / 170.2 n In the formula, θ3 and θ 100 and θ 200 The readings are for the Fann35A viscometer at 3 r / min, 100 r / min, and 200 r / min, respectively.

[0064] Taking the target well drill string assembly as drill pipe × S135s as an example, we can obtain the following from Tables 1 and 2:

[0065] τ Hy =0.511θ3=0.511×7=3.577(Pa);

[0066]

[0067] Substituting the non-Newtonian rheological damping, engineering parameters, and initial angular displacement of the drill bit at the current moment into the second preset formula, the frictional torque of the mass block at the current moment is calculated.

[0068] It should be noted that the calculation methods for the friction torque and non-Newtonian rheological damping of other mass blocks in the target well are the same as those for the friction torque and non-Newtonian rheological damping of the drill bit in the target well, and will not be repeated here.

[0069] Step S102: Substitute the current rotary table speed, the current moment of inertia of the mass block, the current spring stiffness between the mass blocks, the current spring damping between the mass blocks, the current frictional torque of the mass block, and the non-Newtonian rheological damping into the dynamic differential equation of the drill string system in the horizontal well drill string stick-slip vibration analysis model to calculate the angular displacement of the mass block at the next moment.

[0070] In this embodiment, the assumptions included in the constructed horizontal well drill string stick-slip vibration analysis model are as follows:

[0071] (1) Neglect the effect of transverse vibration on torsional vibration;

[0072] (2) The effect of oil-based drilling fluid on the drill string is equivalent to a non-Newtonian rheological damping force;

[0073] (3) The drill bit, drill collar, weighted drill pipe, horizontal section drill pipe and non-horizontal section drill pipe are regarded as multiple mass blocks with concentrated inertia, and the mass blocks are connected by springs and dampers;

[0074] (4) The frictional effect between the drill bit and the rock (formation) is represented by concentrated frictional torque.

[0075] Based on the above assumptions, the constructed horizontal well drill string stick-slip vibration analysis model is as follows: Figure 5 As shown. The initial conditions for the stick-slip vibration analysis model of the horizontal well drill string are: at the initial moment, the top drive rotary table rotates at a speed of V.

[0076] The boundary conditions for the horizontal well drill string stick-slip vibration analysis model are as follows:

[0077] (1) The top drive rotary table speed V and the drilling pressure WOB are constant;

[0078] (2) The torque T transmitted from the drill string to the drill bit r For nonlinear torque T hb With the drill bit inertial torque T b sum.

[0079]

[0080] In the formula, K cb This represents the spring stiffness between mass block b and mass block c. This represents the angular displacement of mass block c. C represents the angular displacement of mass block b. cb This represents the spring damping between mass block b and mass block c. This represents the angular velocity of mass c. C represents the angular velocity of mass b. Hb T represents the non-Newtonian rheological damping between mass block b and the drilling fluid. hb T represents nonlinear torque. b J represents the inertial torque of mass b. b Let represent the moment of inertia of mass block b. This represents the angular acceleration of mass block b.

[0081] Through force analysis, the dynamic differential equations of each mass block in the stick-slip vibration analysis model of the horizontal well drill string are obtained as follows:

[0082] The dynamic differential equation of the non-horizontal section of the drill pipe:

[0083]

[0084] In the formula, J p The moment of inertia of mass p is expressed in kg·m². This represents the angular acceleration of mass p, in rad / s², K. p The spring stiffness between the mass p and the turntable is expressed in N·m / rad; V represents the turntable rotational speed in rad / s; and t represents time. This represents the angular displacement of mass p, in rad and centimeters. p This represents the spring damping between the mass block p and the turntable, with units of N·m·s / rad. This represents the angular velocity of mass p, in rad / s and K. hp This represents the spring stiffness between mass block hp and mass block p. C represents the angular displacement of the mass block hp. hp This represents the spring damping between mass block hp and mass block p. C represents the angular velocity of the mass block hp. Hp This represents the non-Newtonian rheological damping between the mass block p and the drilling fluid, in N·m·s / rad.

[0085] The dynamic differential equation of the horizontal section of the drill pipe:

[0086]

[0087] In the formula, J hp This represents the moment of inertia of the mass block hp. K represents the angular acceleration of the mass block hp. hp This represents the spring stiffness between mass block hp and mass block p. C represents the angular displacement of the mass block hp. hp This represents the spring damping between mass block hp and mass block p. K represents the angular velocity of the mass block hp. pw This represents the spring stiffness between mass blocks pw and hp. C represents the angular displacement of the mass block pw. pw This represents the spring damping between mass blocks pw and hp. C represents the angular velocity of the mass block pw. Hhp T represents the non-Newtonian rheological damping between the mass block hp and the drilling fluid. hhp This represents the frictional torque between the mass block hp and the formation, in N·m.

[0088] The dynamic differential equation of the weighted drill pipe:

[0089]

[0090] In the formula, J pw This represents the moment of inertia of the mass block pw. K represents the angular acceleration of the mass block pw. pw This represents the spring stiffness between mass blocks pw and hp. C represents the angular displacement of the mass block hp. pw This represents the spring damping between mass blocks pw and hp. K represents the angular velocity of the mass block hp. pc This represents the spring stiffness between mass block pc and mass block pw. This represents the angular displacement of the mass block pw. C represents the angular displacement of the mass block pc. pc This represents the spring damping between mass block pc and mass block pw. This represents the angular velocity of the mass block pw. C represents the angular velocity of the mass block pc. Hpw T represents the non-Newtonian rheological damping between the mass block pw and the drilling fluid. hpw The frictional torque between the mass block pw and the formation is expressed in N·m.

[0091] The dynamic differential equation of the drill collar:

[0092]

[0093] In the formula, J pc This represents the moment of inertia of the mass block pc. K represents the angular acceleration of the mass block pc. pc This represents the spring stiffness between mass block pc and mass block pw. C represents the angular displacement of the mass block pw. pc This represents the spring damping between mass block pc and mass block pw. K represents the angular velocity of the mass block pw. pc-b This represents the spring stiffness between mass block pc and mass block b. This represents the angular displacement of mass block b. C represents the angular displacement of the mass block pc. pc-b This represents the spring damping between mass block pc and mass block b. This represents the angular velocity of mass block b. C represents the angular velocity of the mass block pc. Hpc T represents the non-Newtonian rheological damping between the mass block pc and the drilling fluid. hpcThe frictional torque between the mass block pc and the formation is expressed in N·m.

[0094] The dynamic differential equation of the drill bit:

[0095]

[0096] In the formula, J b Let represent the moment of inertia of mass block b. K represents the angular acceleration of mass b. pc-b This represents the spring stiffness between mass block pc and mass block b. This represents the angular displacement of the mass block pc. C represents the angular displacement of mass block b. pc-b This represents the spring damping between mass block pc and mass block b. This represents the angular velocity of the mass block pc. C represents the angular velocity of mass b. Hb T represents the non-Newtonian rheological damping between mass block b and the drilling fluid. hb The frictional torque between mass block b and the formation is expressed in N·m.

[0097] In this embodiment, mass block p represents the non-horizontal section of the drill pipe, mass block hp represents the horizontal section of the drill pipe, mass block pw represents the weighted drill pipe, mass block pc represents the drill collar, and mass block b represents the drill bit.

[0098] By substituting the current rotary table speed, the current moment of inertia of the drill bit, the current spring stiffness between the mass blocks, the current spring damping between the mass blocks, the current frictional torque of the drill bit, and the non-Newtonian rheological damping into the dynamic differential equations of the drill string system in the horizontal well drill string stick-slip vibration analysis model, the angular displacement of the drill bit at the next moment can be calculated. Here, angular velocity and angular acceleration are the first and second derivatives of the angular displacement, respectively.

[0099] It should be noted that the calculation method for the angular displacement of other mass blocks in the target well at the next moment is the same as the calculation method for the angular displacement of the drill bit in the target well at the next moment, and will not be repeated here.

[0100] The dynamic differential equations of each mass block in the stick-slip vibration analysis model of the horizontal well drill string are simplified to obtain the formula.

[0101] Among them, spring stiffness Spring damping Moment of inertia In the formula, G represents the shear modulus of steel, and d o d represents the outer diameter of the drill string. i The inner diameter of the drill string is represented by L, the length of the drill string is represented by c. lC represents the damping coefficient per unit length of the drill string. Generally, C = 0.008K, and ρ represents the density of the steel.

[0102] For example, taking the target well drill string assembly as drill pipe × S135s as an example, we can obtain the following from Tables 1 and 2:

[0103] Non-horizontal section drill pipe length: L v =4536(m);

[0104] Non-horizontal section drill pipe spring stiffness:

[0105]

[0106] Non-horizontal section drill pipe spring damping:

[0107]

[0108] Moment of inertia of the non-horizontal section of the drill pipe:

[0109]

[0110] The calculation methods for the stiffness, damping coefficient, and moment of inertia of other mass blocks in the target well are similar.

[0111] Substituting the drill bit stiffness, damping coefficient, and moment of inertia into the horizontal well drill string stick-slip vibration analysis model, the stick-slip vibration characteristics of the drill bit are obtained. These characteristics include the drill bit's angular displacement, angular velocity, angular acceleration, and torque.

[0112] The angular displacement, angular velocity, angular acceleration, and drill bit torque at multiple moments under different rotary table speeds (64 rad / min, 84 rad / min, 104 rad / min, 124 rad / min, and 144 rad / min) are as follows: Figure 3 As shown.

[0113] The angular displacement, angular velocity, angular acceleration, and drill bit torque at multiple moments under different drilling pressures (60KN, 90KN, 120KN, and 150KN) are as follows: Figure 4 As shown.

[0114] from Figure 3 As can be seen, the drill bit does not rotate immediately at a constant rotary table speed; there is a certain delay in the transmission of rotary table torque downwards. During the rotation of the drill string and drill bit in the horizontal section, they are subject to friction from the formation. When the torque transmitted from the upper drill string is insufficient to overcome the frictional torque, torque accumulation is required, resulting in stick-slip. In the case study, the drill bit exhibited significant stick-slip vibration at a depth of 5820m. Figure 3 As can be seen, with the increase of the rotary table speed, the fluctuations of angular displacement and angular acceleration at the drill bit gradually decrease, which indicates that increasing the rotary table speed can reduce the stick-slip effect at the drill bit.

[0115] from Figure 4 It can be seen that as the drilling pressure increases, the fluctuations in angular displacement and angular acceleration at the drill bit gradually increase, indicating that increasing the drilling pressure will increase the stick-slip effect at the drill bit.

[0116] Step S103: Using the angular displacement of the mass block at the next moment as the initial angular displacement of the mass block at the current moment, return to the step of calculating the frictional torque and non-Newtonian rheological damping of the mass block at the current moment based on the engineering parameters and the initial angular displacement of the mass block at the current moment.

[0117] Step S104: Continue until the next moment is greater than or equal to the preset moment, then end the loop and obtain the angular displacement of the mass block at multiple moments.

[0118] Step S105, and so on, to obtain the angular displacement of each mass block of the target well at multiple times.

[0119] In this embodiment, after obtaining the angular displacement of the mass block at the next moment, the angular displacement of the mass block at the next moment is used as the initial angular displacement of the mass block at the current moment. The process returns to the step of calculating the frictional torque and non-Newtonian rheological damping of the mass block at the current moment based on the engineering parameters and the initial angular displacement of the mass block at the current moment. That is, the angular displacement of the mass block at the next moment is recalculated until the next moment is greater than or equal to a preset moment, that is, the total duration is greater than or equal to a preset total duration. Then the loop ends, and the angular displacement of the mass block at multiple moments is obtained. By analogy, the angular displacement of each mass block of the target well at multiple moments can be obtained.

[0120] For example, the total simulation duration is 100s, the time step is 0.001s, and the angular displacement of the drill bit at multiple moments is as follows: Figure 6a As shown. Further, by taking the first derivative of the angular displacement of the drill bit at multiple moments, the angular velocities of the drill bit at multiple moments are obtained, as shown in the figure. Figure 6b As shown. Further, by taking the second derivative of the angular displacement of the drill bit at multiple moments, the angular acceleration of the drill bit at multiple moments is obtained, as shown in the figure. Figure 6c As shown. Furthermore, based on the angular displacement, angular velocity, and angular acceleration of the drill bit at multiple moments, using the formula... The drill bit torque transmitted from the drill string to the drill bit at multiple moments is calculated. The drill bit torque transmitted from the drill string to the drill bit at multiple moments is as follows: Figure 6d As shown.

[0121] from Figures 6a to 6dAs can be seen, the drill bit did not start immediately under a constant rotary table speed, but only began to rotate after 8.8 seconds. After a period of slight fluctuation, it entered a stable stick-slip vibration with a stickiness duration of about 2.8 seconds and a peak vibration rate of about 17 rad / s, which is 2.5 times the rotary table speed. This indicates that there is a delay in the transmission of rotary table torque to the lower drill string. When the torque transmitted from the upper drill string is insufficient to overcome the frictional torque between the horizontal section of the drill string and the formation, and between the drill bit and the formation, torque accumulation is required, and the drill bit enters a sticky state. When the torque received by the drill bit is greater than the maximum static frictional torque of the formation, the drill bit transitions from a sticky to a slipping state. At this point, the drill bit accelerates instantaneously, with an angular acceleration reaching 5 rad / s. 2 This will cause significant damage to the horizontal section of the drill string and drill bit.

[0122] Step S20: Evaluate the stick-slip vibration level of each mass block of the target well based on the angular displacement to obtain the stick-slip vibration rating of each mass block of the target well.

[0123] In some specific embodiments, reference is made to Figure 11 , Figure 11 for Figure 1 A detailed flowchart of step S20. (See attached diagram.) Figure 11 As shown, step S20 includes:

[0124] Step S201: For any mass block of the target well, calculate the angular velocity of the mass block at multiple moments based on the angular displacement of the mass block at multiple moments;

[0125] Step S202: Select the maximum and minimum angular velocities from the angular velocities of the mass block at multiple moments;

[0126] Step S203: Substitute the maximum angular velocity and the minimum angular velocity into the third preset formula to calculate the stick-slip vibration evaluation index value of the mass block.

[0127] Step S204: Based on the stick-slip vibration evaluation index value, find the stick-slip vibration rating corresponding to the stick-slip vibration evaluation index value of the mass block through the stick-slip vibration level standard table, and obtain the stick-slip vibration rating of the mass block.

[0128] The third preset formula is as follows:

[0129]

[0130] In the formula, SSI represents the stick-slip vibration rating of the mass block. This represents the maximum angular velocity of mass block b. V represents the minimum angular velocity of mass block b, and V represents the rotational speed of the turntable;

[0131] Step S205, and so on, to obtain the stick-slip vibration rating of each mass block of the target well.

[0132] In this embodiment, for the drill bit of the target well, the first-order derivative of the angular displacement of the drill bit at multiple moments is calculated to obtain the angular velocity of the drill bit at multiple moments. The maximum and minimum angular velocities are selected from the angular velocities of the drill bit at multiple moments, and then substituted into the third preset formula. The stick-slip vibration evaluation index value of the drill bit is calculated. The stick-slip vibration rating corresponding to the evaluation index value is then found using the stick-slip vibration level standard table, thus obtaining the stick-slip vibration rating of the drill bit. The stick-slip vibration level standard table is shown in Table 3.

[0133] Table 3

[0134]

[0135]

[0136] According to Table 3 of the stick-slip vibration rating standard, when the stick-slip vibration evaluation index value (SSI) is less than 0.5, the stick-slip vibration rating of the mass block is low; when the stick-slip vibration evaluation index value (SSI) is in the range of [0.5, 1.0), the stick-slip vibration rating of the mass block is medium; when the stick-slip vibration evaluation index value (SSI) is in the range of [1.0, 1.5], the stick-slip vibration rating of the mass block is high; and when the stick-slip vibration evaluation index value (SSI) is greater than 1.5, the stick-slip vibration rating of the mass block is severe.

[0137] The effects of different parameters (rotary speed, drilling pressure, horizontal section length, and drill collar length) on the stick-slip vibration index (SSI) are as follows: Figures 7a to 7d As shown in the figure. The influence of turntable rotation speed on the evaluation index value of stick-slip vibration is as follows. Figure 7a As shown, the influence of drilling pressure on the evaluation index value of stick-slip vibration is as follows: Figure 7b As shown, the influence of the horizontal segment length on the stick-slip vibration evaluation index value is as follows: Figure 7c As shown, the influence of drill collar length on the stick-slip vibration evaluation index value is as follows: Figure 7d As shown.

[0138] from Figure 7a It can be seen that if the rotary table speed is higher than 104 r / min, the stick-slip vibration evaluation index value SSI < 1, and the stick-slip vibration level is medium or low, then the rotary table speed can be maintained at the drilling site; from Figure 7b It can be seen that if the drilling pressure is below 90 kN, the stick-slip vibration evaluation index value SSI < 1, and the stick-slip vibration level is medium or low, then the drilling site can maintain this drilling pressure; from Figure 7cIt can be seen that if the horizontal section length is less than 513m, the stick-slip vibration evaluation index value SSI < 1, and the stick-slip vibration level is medium or low, then the drilling site can maintain this horizontal section length; from Figure 7d It can be seen that if the drill collar length is greater than 67m, the stick-slip vibration evaluation index value SSI < 1, and the stick-slip vibration level is medium or low, then the drilling site can maintain this horizontal section length.

[0139] Step S30: Based on the stick-slip vibration suppression strategy corresponding to the stick-slip vibration rating, suppress the stick-slip vibration of the tubing in each mass block of the target well.

[0140] In some specific embodiments, step S30 includes:

[0141] If the stick-slip vibration rating is higher than the preset level, then the parameter range corresponding to the stick-slip vibration rating being less than or equal to the preset level is obtained based on the stick-slip vibration rating chart.

[0142] Adjust the engineering parameters of the target well to the specified range to suppress the stick-slip vibration of the tubing in each mass block of the target well.

[0143] In this embodiment, stick-slip vibration is simulated by orthogonally combining different rotary table speeds, drilling pressures, weighted drill pipe lengths, and drill collar lengths to obtain corresponding stick-slip vibration levels, which are then plotted on a stick-slip vibration level chart. Different stick-slip vibration index (SSI) levels are represented by different color distributions: low stick-slip vibration is represented by green; medium stick-slip vibration by yellow; high stick-slip vibration by orange; and severe stick-slip vibration by red. If the stick-slip vibration level is high or severe, the drilling system quickly identifies the color distribution on the stick-slip vibration level chart to obtain the boundary parameter range where the SSI value < 1, i.e., the parameter range corresponding to a stick-slip vibration level less than or equal to medium. When the parameters used at the drilling site cause the stick-slip vibration evaluation index value SSI > 1, the system will automatically trigger an early warning and adjust the engineering parameters of the target well to the boundary parameter range where the stick-slip vibration evaluation index value SSI < 1, thereby suppressing the stick-slip vibration of the tubing in each mass block of the target well.

[0144] For example, a stick-slip vibration level chart obtained by orthogonal combination of the weighted drill pipe length and drill collar length is shown in the figure. Figure 8 As shown, from Figure 8It can be seen that the effects of weighted drill pipe length and drill collar length on drill bit stick-slip show opposite trends. It is necessary to comprehensively consider and evaluate the effects of weighted drill pipe length and drill collar length on drill bit stick-slip, and calculate the SSI value for the stick-slip vibration rating of the target well under different orthogonal combinations of weighted drill pipe length and drill collar length.

[0145] The stick-slip vibration level chart obtained by orthogonal combination of rotary table speed and drilling pressure is shown below. Figure 9 As shown. From Figure 9 It is evident that since the effects of drill pressure and rotary table speed on drill bit stick-slip exhibit opposite trends, it is necessary to comprehensively consider and evaluate the influence of drill pressure and rotary table pressure on drill bit stick-slip, and calculate the SSI value for the stick-slip vibration rating of the target well under different orthogonal combinations of rotary table speed and drill pressure. The results are as follows... Figure 9 As shown, the horizontal axis of the stick-slip vibration level chart represents rotary table speed, and the vertical axis represents drill pressure. When the intersection of drill pressure and rotary table speed is green, the drill bit can drill normally. The stick-slip vibration chart can effectively take into account both drill pressure and rotational speed, thereby suppressing the stick-slip effect of the drill bit.

[0146] In this embodiment, based on the engineering parameters of the target well, the angular displacement of each mass block of the target well at multiple times is calculated using a horizontal well drill string stick-slip vibration analysis model. The target well is a long horizontal well to be drilled. Based on the angular displacement, the stick-slip vibration level of each mass block of the target well is evaluated, resulting in a stick-slip vibration rating for each mass block. Based on the stick-slip vibration suppression strategy corresponding to the rating, the stick-slip vibration of the drill string in each mass block of the target well is suppressed. Through this embodiment, since different stick-slip vibration ratings present different color distributions, the stick-slip vibration of the drill string under oil-based drilling fluid conditions can be accurately determined, and the parameter range corresponding to a stick-slip vibration rating less than or equal to the intermediate level can be obtained. This allows for targeted optimization of the engineering parameters and drill string assembly of the target well, achieving the goal of suppressing drill string stick-slip vibration. This solves the technical problem in related technologies where the stick-slip vibration of the drill string system cannot be effectively mitigated or suppressed during long horizontal drilling.

[0147] Secondly, embodiments of the present invention also provide a stick-slip vibration suppression device.

[0148] In one embodiment, reference is made to Figure 12 , Figure 12 This is a functional module diagram of an embodiment of the stick-slip vibration suppression device of the present invention. Figure 12 As shown, the stick-slip vibration suppression device includes:

[0149] The calculation module 10 is configured to calculate the angular displacement of each mass block of the target well at multiple times based on the engineering parameters of the target well and through the stick-slip vibration analysis model of the horizontal well drill string. The target well is a long horizontal well to be drilled.

[0150] The rating module 20 is configured to evaluate the stick-slip vibration level of each mass block of the target well based on the angular displacement, and obtain the stick-slip vibration rating of each mass block of the target well.

[0151] The parameter adjustment module 30 is configured to suppress the stick-slip vibration of the tubing in each mass block of the target well based on the stick-slip vibration suppression strategy corresponding to the stick-slip vibration rating.

[0152] Optionally, in one embodiment, the engineering parameters include: shear modulus of steel, drill string outer diameter, drill string inner diameter, drill string length, drill string damping coefficient per unit length, steel density, rotary table speed, static friction coefficient, sliding friction coefficient, drilling pressure, radius of each mass block, yield stress, flowability index, fluid consistency coefficient, mud thickness, contact area between fluid and drill string, and rotary table speed;

[0153] The mass blocks of the target well include: non-horizontal drill pipe, horizontal drill pipe, weighted drill pipe, drill collar, and drill bit.

[0154] Optionally, in one embodiment, the computing module 10 is configured to:

[0155] For any mass block of the target well, the frictional torque and non-Newtonian rheological damping of the mass block at the current moment are calculated based on the engineering parameters and the initial angular displacement of the mass block at the current moment.

[0156] Substitute the current rotary table speed, the current moment of inertia of the mass block, the current spring stiffness between the mass blocks, the current spring damping between the mass blocks, the current frictional torque of the mass block, and the non-Newtonian rheological damping into the dynamic differential equation of the drill string system in the horizontal well drill string stick-slip vibration analysis model to calculate the angular displacement of the mass block at the next moment.

[0157] The angular displacement of the mass block at the next moment is taken as the initial angular displacement of the mass block at the current moment. The process is then repeated to calculate the frictional torque and non-Newtonian rheological damping of the mass block at the current moment based on the engineering parameters and the initial angular displacement of the mass block at the current moment.

[0158] The loop continues until the next moment is greater than or equal to the preset moment, at which point the loop ends and the angular displacement of the mass block at multiple moments is obtained.

[0159] By analogy, the angular displacements of each mass block of the target well at multiple times can be obtained.

[0160] Optionally, in one embodiment, the computing module 10 is configured to:

[0161] Substituting the engineering parameters and the initial angular displacement of the mass block at the current moment into the first preset formula, the non-Newtonian rheological damping of the mass block at the current moment is calculated;

[0162] Substituting the non-Newtonian rheological damping, the engineering parameters, and the initial angular displacement of the mass block at the current moment into the second preset formula, the frictional torque of the mass block at the current moment is calculated.

[0163] The first preset formula is as follows:

[0164]

[0165] In the formula, C Hb A represents the non-Newtonian rheological damping between mass block b and the drilling fluid. f τ represents the contact area between the fluid and the drill string. Hy This represents the yield stress in a non-Newtonian fluid model. denoted by angular displacement of mass block b, k represents fluid consistency coefficient, n represents flowability index, V represents rotary table speed, and Δ represents mud thickness.

[0166] The second preset formula is as follows:

[0167]

[0168] In the formula, T hb T represents the frictional torque between mass block b and the formation; r This represents the torque transmitted from the drill string to the mass block b. Let T represent the angular velocity of mass b, Δv represent the threshold of the zero velocity interval, and T represent the angular velocity of mass b. sb T represents the maximum static friction torque. sb =μ sb *WOB*R b μ sb R represents the maximum static friction coefficient, WOB represents the drilling pressure, and R represents the drilling pressure. b T represents the radius of mass block b; cb T represents the sliding friction torque. cb =μ cb *WOB*R b μ cb ξ represents the coefficient of sliding friction; ξ∈[0,1] is an empirical constant and defines the rate of decrease of frictional torque.

[0169] Optionally, in one embodiment, the dynamic differential equation of the drill string system in the horizontal well drill string stick-slip vibration analysis model is as follows:

[0170]

[0171]

[0172] In the formula, the subscripts p, hp, pw, pc, and b are the identifiers of the mass blocks, and J represents the moment of inertia of each mass block. Let V represent the angular acceleration of each mass block, K represent the spring stiffness between the mass blocks, V represent the rotational speed of the turntable, and t represent time. Let C represent the angular displacement of each mass block, and let C represent the spring damping between the mass blocks. C represents the angular velocity of each mass block. H T represents the non-Newtonian rheological damping between each mass block and the drilling fluid. h This represents the frictional torque between each mass block and the formation.

[0173] Optionally, in one embodiment, the rating module 20 is configured to:

[0174] For any mass block of the target well, the angular velocity of the mass block at multiple times is calculated based on the angular displacement of the mass block at multiple times.

[0175] Select the maximum and minimum angular velocities from the angular velocities of the mass block at multiple moments;

[0176] Substituting the maximum and minimum angular velocities into the third preset formula, the stick-slip vibration evaluation index value of the mass block is calculated.

[0177] Based on the stick-slip vibration evaluation index value, the stick-slip vibration rating corresponding to the stick-slip vibration evaluation index value of the mass block is found through the stick-slip vibration level standard table, and the stick-slip vibration rating of the mass block is obtained.

[0178] The third preset formula is as follows:

[0179]

[0180] In the formula, SSI represents the stick-slip vibration rating of the mass block. This represents the maximum angular velocity of mass block b. V represents the minimum angular velocity of mass block b, and V represents the rotational speed of the turntable;

[0181] By analogy, the stick-slip vibration ratings of each mass block of the target well are obtained.

[0182] Optionally, in one embodiment, the parameter adjustment module 30 is configured to:

[0183] If the stick-slip vibration rating is higher than the preset level, then the parameter range corresponding to the stick-slip vibration rating being less than or equal to the preset level is obtained based on the stick-slip vibration rating chart.

[0184] Adjust the engineering parameters of the target well to the specified range to suppress the stick-slip vibration of the tubing in each mass block of the target well.

[0185] The functions of each module in the above-mentioned stick-slip vibration suppression device correspond to the steps in the above-mentioned stick-slip vibration suppression method embodiment, and their functions and implementation processes will not be described in detail here.

[0186] Thirdly, embodiments of the present invention also provide an electronic device, the structure of which is as follows: Figure 13 As shown, it includes: a memory and a processor, wherein the processor is used to read and execute the computer program stored in the memory to implement the aforementioned stick-slip vibration suppression method.

[0187] Fourthly, embodiments of the present invention also provide a computer storage medium storing computer-executable instructions, which, when executed, implement the aforementioned stick-slip vibration suppression method.

[0188] Fifthly, embodiments of the present invention provide a computer program product, which is stored in a storage medium and executed by at least one processor to implement the various processes of the above-described stick-slip vibration suppression method embodiments, and can achieve the same technical effect. To avoid repetition, it will not be described again here.

[0189] Finally, it should be noted that while some processes described in the embodiments of the present invention include multiple operations or steps that appear in a specific order, it should be understood that these operations or steps may not be executed in the order they appear in the embodiments of the present invention, or may be executed in parallel. The sequence number of the operation is only used to distinguish different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed sequentially or in parallel, and these operations or steps may be combined.

[0190] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for suppressing stick-slip vibration, characterized in that, The method includes: Based on the engineering parameters of the target well, the angular displacement of each mass block of the target well at multiple times is calculated using the stick-slip vibration analysis model of the horizontal well drill string. The target well is a long horizontal well to be drilled. Based on the angular displacement, the stick-slip vibration level of each mass block of the target well is evaluated to obtain the stick-slip vibration rating of each mass block of the target well. Based on the stick-slip vibration suppression strategy corresponding to the stick-slip vibration rating, the stick-slip vibration of the tubing in each mass block of the target well is suppressed.

2. The stick-slip vibration suppression method according to claim 1, characterized in that, The engineering parameters include: shear modulus of steel, drill string outer diameter, drill string inner diameter, drill string length, drill string damping coefficient per unit length, steel density, rotary table speed, static friction coefficient, sliding friction coefficient, drilling pressure, radius of each mass block, yield stress, flowability index, fluid consistency coefficient, mud thickness, contact area between fluid and drill string, and rotary table speed. The mass blocks of the target well include: non-horizontal drill pipe, horizontal drill pipe, weighted drill pipe, drill collar, and drill bit.

3. The stick-slip vibration suppression method according to claim 2, characterized in that, The step of calculating the angular displacement of each mass block of the target well at multiple times using a horizontal well drill string stick-slip vibration analysis model based on the engineering parameters of the target well includes: For any mass block of the target well, the frictional torque and non-Newtonian rheological damping of the mass block at the current moment are calculated based on the engineering parameters and the initial angular displacement of the mass block at the current moment. Substitute the current rotary table speed, the current moment of inertia of the mass block, the current spring stiffness between the mass blocks, the current spring damping between the mass blocks, the current frictional torque of the mass block, and the non-Newtonian rheological damping into the dynamic differential equation of the drill string system in the horizontal well drill string stick-slip vibration analysis model to calculate the angular displacement of the mass block at the next moment. The angular displacement of the mass block at the next moment is taken as the initial angular displacement of the mass block at the current moment. The process is then repeated to calculate the frictional torque and non-Newtonian rheological damping of the mass block at the current moment based on the engineering parameters and the initial angular displacement of the mass block at the current moment. The loop continues until the next moment is greater than or equal to the preset moment, at which point the loop ends and the angular displacement of the mass block at multiple moments is obtained. By analogy, the angular displacements of each mass block of the target well at multiple times can be obtained.

4. The stick-slip vibration suppression method according to claim 3, characterized in that, The step of calculating the frictional torque and non-Newtonian rheological damping of the mass block at the current moment based on the engineering parameters and the initial angular displacement of the mass block at the current moment includes: Substituting the engineering parameters and the initial angular displacement of the mass block at the current moment into the first preset formula, the non-Newtonian rheological damping of the mass block at the current moment is calculated; Substituting the non-Newtonian rheological damping, the engineering parameters, and the initial angular displacement of the mass block at the current moment into the second preset formula, the frictional torque of the mass block at the current moment is calculated. The first preset formula is as follows: In the formula, C Hb A represents the non-Newtonian rheological damping between mass block b and the drilling fluid. f τ represents the contact area between the fluid and the drill string. Hy This represents the yield stress in a non-Newtonian fluid model. denoted by angular displacement of mass block b, k represents fluid consistency coefficient, n represents flowability index, V represents rotary table speed, and Δ represents mud thickness. The second preset formula is as follows: In the formula, T hb T represents the frictional torque between mass block b and the formation; r This represents the torque transmitted from the drill string to the mass block b. Let T represent the angular velocity of mass b, Δv represent the threshold of the zero velocity interval, and T represent the angular velocity of mass b. sb T represents the maximum static friction torque. sb =μ sb *WOB*R b μ sb R represents the maximum static friction coefficient, WOB represents the drilling pressure, and R represents the drilling pressure. b T represents the radius of mass block b; cb T represents the sliding friction torque. cb =μ cb *WOB*R b μ cb ξ represents the coefficient of sliding friction; ξ∈[0,1] is an empirical constant and defines the rate of decrease of frictional torque.

5. The stick-slip vibration suppression method according to claim 3, characterized in that, The dynamic differential equations of the drill string system in the horizontal well drill string stick-slip vibration analysis model are as follows: In the formula, the subscripts p, hp, pw, pc, and b are the identifiers of the mass blocks, and J represents the moment of inertia of each mass block. Let V represent the angular acceleration of each mass block, K represent the spring stiffness between the mass blocks, V represent the rotational speed of the turntable, and t represent time. Let C represent the angular displacement of each mass block, and let C represent the spring damping between the mass blocks. C represents the angular velocity of each mass block. H T represents the non-Newtonian rheological damping between each mass block and the drilling fluid. h This represents the frictional torque between each mass block and the formation.

6. The stick-slip vibration suppression method according to claim 1, characterized in that, The step of evaluating the stick-slip vibration level of each mass block of the target well based on the angular displacement to obtain the stick-slip vibration rating of each mass block of the target well includes: For any mass block of the target well, the angular velocity of the mass block at multiple times is calculated based on the angular displacement of the mass block at multiple times. Select the maximum and minimum angular velocities from the angular velocities of the mass block at multiple moments; Substituting the maximum and minimum angular velocities into the third preset formula, the stick-slip vibration evaluation index value of the mass block is calculated. Based on the stick-slip vibration evaluation index value, the stick-slip vibration rating corresponding to the stick-slip vibration evaluation index value of the mass block is found through the stick-slip vibration level standard table, and the stick-slip vibration rating of the mass block is obtained. The third preset formula is as follows: In the formula, SSI represents the stick-slip vibration rating of the mass block. This represents the maximum angular velocity of mass block b. V represents the minimum angular velocity of mass block b, and V represents the rotational speed of the turntable; By analogy, the stick-slip vibration ratings of each mass block of the target well are obtained.

7. The stick-slip vibration suppression method according to claim 1, characterized in that, The step of suppressing the stick-slip vibration of the tubing in each mass block of the target well based on the stick-slip vibration suppression strategy corresponding to the stick-slip vibration rating includes: If the stick-slip vibration rating is higher than the preset level, then the parameter range corresponding to the stick-slip vibration rating being less than or equal to the preset level is obtained based on the stick-slip vibration rating chart. Adjust the engineering parameters of the target well to the specified range to suppress the stick-slip vibration of the tubing in each mass block of the target well.

8. A stick-slip vibration suppression device, characterized in that, The device includes: The calculation module is configured to calculate the angular displacement of each mass block of the target well at multiple times based on the engineering parameters of the target well and through the stick-slip vibration analysis model of the horizontal well drill string. The target well is a long horizontal well to be drilled. The rating module is configured to evaluate the stick-slip vibration level of each mass block of the target well based on the angular displacement, and obtain the stick-slip vibration rating of each mass block of the target well. The parameter adjustment module is configured to suppress the stick-slip vibration of the tubing in each mass block of the target well based on the stick-slip vibration suppression strategy corresponding to the stick-slip vibration rating.

9. The stick-slip vibration suppression device according to claim 8, characterized in that, The computing module is configured to: For any mass block of the target well, the frictional torque and non-Newtonian rheological damping of the mass block at the current moment are calculated based on the engineering parameters and the initial angular displacement of the mass block at the current moment. Substitute the current rotary table speed, the current moment of inertia of the mass block, the current spring stiffness between the mass blocks, the current spring damping between the mass blocks, the current frictional torque of the mass block, and the non-Newtonian rheological damping into the dynamic differential equation of the drill string system in the horizontal well drill string stick-slip vibration analysis model to calculate the angular displacement of the mass block at the next moment. The angular displacement of the mass block at the next moment is taken as the initial angular displacement of the mass block at the current moment. The process is then repeated to calculate the frictional torque and non-Newtonian rheological damping of the mass block at the current moment based on the engineering parameters and the initial angular displacement of the mass block at the current moment. The loop continues until the next moment is greater than or equal to the preset moment, at which point the loop ends and the angular displacement of the mass block at multiple moments is obtained. By analogy, the angular displacements of each mass block of the target well at multiple times can be obtained.

10. The stick-slip vibration suppression device according to claim 8, characterized in that, The rating module is configured to: For any mass block of the target well, the angular velocity of the mass block at multiple times is calculated based on the angular displacement of the mass block at multiple times. Select the maximum and minimum angular velocities from the angular velocities of the mass block at multiple moments; Substituting the maximum and minimum angular velocities into the third preset formula, the stick-slip vibration evaluation index value of the mass block is calculated. Based on the stick-slip vibration evaluation index value, the stick-slip vibration rating corresponding to the stick-slip vibration evaluation index value of the mass block is found through the stick-slip vibration level standard table, and the stick-slip vibration rating of the mass block is obtained. The third preset formula is as follows: In the formula, SSI represents the stick-slip vibration rating of the mass block. This represents the maximum angular velocity of mass block b. V represents the minimum angular velocity of mass block b, and V represents the rotational speed of the turntable; By analogy, the stick-slip vibration ratings of each mass block of the target well are obtained.

11. An electronic device, characterized in that, include: Memory and processor; The processor is configured to read and execute the computer program stored in the memory to implement the steps of the stick-slip vibration suppression method as described in any one of claims 1-7.

12. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed, implement the steps of the stick-slip vibration suppression method as described in any one of claims 1-7.

13. A computer program product comprising a computer program / instructions, characterized in that, When the computer program / instruction is executed by the processor, it implements the steps of the stick-slip vibration suppression method as described in any one of claims 1-7.

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