Mitigation of Torsional Stick-Slip Vibrations in Oil Well Drilling through PDC Bit Design: Putting Theories to the Test

Drillstring vibrations and in particular stick-slip and bit-bounce are detrimental to oil-well drilling operations. Controlling these vibrations is essential because they may cause equipment failures and damage to the oil-well. A simple model that adequately captures the dynamics is used to simulate the effects of varying operating conditions on stick-slip and bit-bounce interactions. It is shown that the conditions at the bit/formation interface, such as bit speed and formation stiffness, are major factors in shaping the dynamic response. Due to the varying and uncertain nature of these conditions, simple operational guidelines or active rotary table control strategies are not sufficient to eliminate both stick-slip and bit-bounce. It is demonstrated that an additional active controller for the axial motion can be effective in suppressing both stick-slip and bit-bounce. It is anticipated that if the proposed approach is implemented, smooth drilling will be possible for a wide range of conditions.

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Multi-dimensional semi-analytical model for axial stick–slip of a rod sliding on a surface with Coulomb friction

Advances in Mechanical Engineering ◽

10.1177/1687814019831533 ◽

2019 ◽

Vol 11 (3) ◽

pp. 168781401983153

Author(s):

Sigve Hovda

Keyword(s):

Constant Velocity ◽

Coulomb Friction ◽

Element Model ◽

Oil Well ◽

Stick Slip ◽

Well Drilling ◽

Lumped Element ◽

Fundamental Understanding ◽

Real Time Applications ◽

Lumped Element Model

A multi-dimensional lumped element model of a long non-rotating rod that moves on a slick surface with both dynamic and static Coulomb friction is outlined. The rod is accelerated to a constant velocity, and the free end of the rod experiences the effect of stick and slip. This article describes a new modeling approach, where the model is able to switch between different linear semi-analytical sub-models, depending on how much of the rod is moving. Fundamental understanding of the stick–slip effect is revealed, and a potential shortcoming of the model is also discussed. The model is computationally effective and may be suitable for real-time applications in, for instance, oil-well drilling.

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Simulation of Oil Well Drilling System Using Distributed–Lumped Modelling Technique

Modelling ◽

10.3390/modelling1020011 ◽

2020 ◽

Vol 1 (2) ◽

pp. 175-197

Author(s):

Panagiotis Athanasiou ◽

Yaser Hadi

Keyword(s):

Oil And Gas ◽

Long Strings ◽

Lumped Parameter Model ◽

Oil Well ◽

Drilling Depth ◽

Stick Slip ◽

Well Drilling ◽

Actual Measurement ◽

Breakdown Time ◽

Modelling Methodology

The strengths and torque of well-boiling hydrocarbons are of utmost significance. Boiling a well is one of the most critical steps in the discovery and production of oil and gas. The well’s boiling process is expensive because the drilling depth can be as much as 7000 meters. Any delay (breakdown time) in boiling costs a lot of money for hydrocarbon firms. Various boiler parameters are continuously tracked and regulated to avoid drilling delays. This paper focuses on the vibrations occurring at the bottom hole assembly (BHA) stick-slip. Two modelling methods, the lumped parameter model and the combination of the distributed–lumped (D–L) parameter model, were used and compared to the actual measurement performance. The D–L model was found to be more precise, particularly for long strings. Using the simulations, the most comprehensive modelling methodology is introduced.

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Rheological behaviour of oil well drilling fluids. 2F, 94R

International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts ◽

10.1016/0148-9062(75)91569-7 ◽

1975 ◽

Vol 12 (8) ◽

pp. 117

Keyword(s):

Rheological Behaviour ◽

Drilling Fluids ◽

Oil Well ◽

Well Drilling

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Experimental Study on Axial Impact Mitigating Stick-Slip Vibration with a PDC Bit

Shock and Vibration ◽

10.1155/2021/8897283 ◽

2021 ◽

Vol 2021 ◽

pp. 1-8

Author(s):

Yong Wang ◽

Hongjian Ni ◽

Yiliu (Paul) Tu ◽

Ruihe Wang ◽

Xueying Wang ◽

...

Keyword(s):

Impact Force ◽

Impact Load ◽

Similarity Theory ◽

Impact Frequency ◽

Stick Slip ◽

Axial Impact ◽

Pdc Bit ◽

Fluctuation Amplitude ◽

Rotary Speed ◽

The Impact

Stick-slip vibration reduces the drilling rate of penetration, causes early wear of bits, and threatens the safety of downhole tools. Therefore, it is necessary to study suppression methods of stick-slip vibration to achieve efficient and safe drilling. Field tests show that the use of downhole axial impactors is helpful to mitigate stick-slip vibration and improve rock-breaking efficiency. However, there are many deficiencies in the study of how axial impact load affects stick-slip vibration of a PDC bit. In this paper, based on the two-degrees-of-freedom spring-mass-damper model and similarity theory, a laboratory experiment device for suppressing stick-slip vibration of a PDC bit under axial impact load has been developed, and systematic experimental research has been carried out. The results show that the axial impact force can suppress the stick-slip vibration by reducing the amplitude of weight on bit and torque fluctuations and by increasing the main frequency of torque. The amplitude of impact force affects the choice of the optimal back-rake angle. The impact frequency is negatively correlated with the fluctuation amplitude of the rotary speed. When the impact frequency is greater than 100 Hz, the fluctuation amplitude of the rotary speed will not decrease.

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Multi-objective optimization of oil well drilling using elitist non-dominated sorting genetic algorithm

Petroleum Science ◽

10.1007/s12182-014-0321-x ◽

2014 ◽

Vol 11 (1) ◽

pp. 97-110 ◽

Cited By ~ 13

Author(s):

Chandan Guria ◽

Kiran K. Goli ◽

Akhilendra K. Pathak

Keyword(s):

Genetic Algorithm ◽

Oil Well ◽

Multi Objective Optimization ◽

Well Drilling ◽

Multi Objective

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Design and HIL Validation of an Effective Super-Twisting Controller for Stick-Slip Suppression in Drill-String Systems

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.4051853 ◽

2021 ◽

Author(s):

Abdelbasset Krama ◽

Mohamed Gharib ◽

Shady S. Refaat ◽

Alan Palazzolo

Keyword(s):

Power Plants ◽

High Efficiency ◽

Sliding Mode ◽

Drill String ◽

Experimental Investigations ◽

Small Scale ◽

Oil Well ◽

Stick Slip ◽

Rock Interaction ◽

The Real

Abstract This paper presents a novel controller for drill string systems based on a super-twisting sliding mode theory. The aim is to eliminate the stick-slip vibration and maintain a constant drill string velocity at the desired reference value. The proposed controller inherently attenuates the torsional vibration while ensuring the stability and high efficiency of the drill string. A discontinuous lumped-parameter torsional model of vertical drill strings based on four components (rotary table, drill pipes, drill collars and drill bit) is considered. The Karnopp friction model is adopted to simulate the nonlinear bit-rock interaction phenomena. In order to provide a more accurate evaluation, the proposed drill string controller is implemented with the induction motor, a variable frequency drive and a gearbox to closely mirror the real environment of oil well drill strings. The increasing demand for prototyping and testing high-power plants in realistic and safe environments has led to the advancement of new types of experimental investigations without hurting the real system or building a small-scale prototype for testing. The dynamic performance of the proposed controller has been investigated with MATLAB software as well as in a novel hardware in-the-loop (HIL) testing platform. A power plant is modeled and implemented in the real-time simulator OPAL-RT 5600, whereas the controllers are implemented in the dSPACE 1103 control board. The results obtained through simulation and HIL testing demonstrate the feasibility and high performance of the proposed controller.

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