Results 161 to 170 of about 4,548 (230)

Fast and Efficient Mitigation of Coupled Axial-Torsional Drillstring Vibrations through State-Feedback Linear-Quadratic-Integral (LQI) Control

SPE Journal
In the exploitation of subsurface hydrocarbon and geothermal energy, more than 50% of total expenses are typically attributed to drilling and well completion. Coupled triaxial vibrations in the drilling system, excited by various mechanical, hydraulic,
Yifan Zhang, P. Ashok, J. Aguirre, Dongmei Chen, Eric van Oort   +4 more
semanticscholar   +1 more source

Drillstring Fatigue Performance

SPE Drilling Engineering, 1990
Summary The life-prediction technique of a whole-life fatigue model was applied to drillstring components. Good agreement existed between the life predictions and the experimental data of drill collars. These life predictions were then used to study the effects of material properties and commonly used thread profiles on the fatigue life ...
openaire   +1 more source

Drillstring Vibration and Wellbore Instability

Journal of Energy Resources Technology, 2002
Wellbore instability can be attributed to several causes. The ones thought to be most important include: chemical interaction with the drilling fluid, high tectonic stresses, and insufficient mud weight. Drillstring vibration, although not traditionally addressed as a potential cause, might influence the stability of wellbores drilled in specific ...
Joa˜o Carlos R. Pla´cido, He´lio M. R. Santos, Yadira Diaz Galeano   +2 more
openaire   +1 more source

Efficient Drillstring-Wellbore Contact Model and Implications for Real-Time Modeling of Complex Downhole Mechanics

SPE Annual Technical Conference and Exhibition
Determining the contact forces between the drillstring and wellbore wall remains a computational challenge; one that prevents real-time estimation of complex downhole mechanics.
J. K. Wilson
semanticscholar   +1 more source

Elimination of Drillstring Failures

Journal of Petroleum Technology, 1994
Drillstring failures can be prevented by drilling a straight, useful hole free of severe doglegs with larger-than-normal drillstring components. The maximum drill-collar diameters shown in the Lubinski tables in the IADC Drilling Manual, Sec. P1,1 for straight-hole drilling are essential for drilling a straight, useful hole and preventing drillstring ...
openaire   +1 more source

Directional Drillstring Dynamics

2008
A rotating rod under load may execute vibration in different ways: transversal (bending), longitudinal (axial), torsional, or a combination of any of those. In this article, the dynamics of a rotating directional drilling system, constrained to rotate in a borehole, is investigated using the finite element formulation.
Fredy Coral Alamo, Hans Ingo Weber, Harry Saavedra Espinoza   +2 more
openaire   +1 more source

Investigation on random vibration of a drillstring

Journal of Sound and Vibration, 2017
Abstract This paper investigates the axial-torsional coupled vibration of a drill-string under combined deterministic and random excitations. Finite element method (FEM) is used to model the system. The random excitation at the bit-rock interaction, which is considered in the bit axial direction, is treated as Gaussian white noise.
Hongyuan Qiu, Jianming Yang, Stephen Butt, Jinghan Zhong   +3 more
openaire   +1 more source

An Overview of Drillstring Models

2015
Over the last half-century, extensive research effort has been conducted to mathematically describe the physical phenomena occurring in real wells. This chapter presents a brief compilation of the most popular modeling strategies allowing the analysis and control of a vertical oilwell drilling system.
Martha Belem Saldivar Márquez, Islam Boussaada, Hugues Mounier, Silviu-Iulian Niculescu   +3 more
openaire   +1 more source

Self-Excited Vibrations in Drillstrings

SPE Annual Technical Conference and Exhibition, 1987
Abstract Vibrations created by drag bits can cause premature failure of drillstring components and fracture cutters. Unfortunately, there has been no theory that adequately explains how drag bits excite drillstrings. Our paper shows that these vibrations are self excited by the interaction of drillstring, bit, and formation. Results show
C.A. Zamudio, J.L. Tlusty, D.W. Dareing
openaire   +1 more source

Distributed Nonuniform Friction and Vibration Mode Switching of Drillstring in Complex Wellbore Trajectories

SPE Journal
To investigate the influence of complex wellbore trajectories on the torsional dynamics of drillstrings, we focus this study on off-bottom conditions, establishing a distributed torsional dynamic model based on real wellbore trajectory data that ...
Siqi Li, Zhuo Chen, Yingcao Zhou, Jiapan Dong, Wei Li, Shaoyong Gao   +5 more
semanticscholar   +1 more source