Results 121 to 130 of about 1,167 (156)

Torsional Vibration Analysis of Drillstrings in Blasthole Drilling

Volume 11: Mechanical Systems and Control, 2008
Reducing vibrations in well drilling has a significant effect on improving the overall performance of the drilling process. Vibrations may affect the drilling process in different ways, i.e., reducing durability of the drillstring’s elements, reducing the rate of penetration, and deviating the drilling direction.
Omid Aminfar, Amir Khajepour
openaire   +1 more source

Active control of drillstring vibrations by mode localization

Journal of Structural Control, 1997
AbstractA method of controlling vibrations in a drillstring is proposed. The method is based on altering the system eigenstructure by feedback such that the closed loop system mode shapes are spatially confined to small geometric regions. Both active and passive means can be used to realize the resulting designs. Simulations are used to show the effect
A. S. Yigit, M. D. Al‐Ansary, M. Khalid   +2 more
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A Review of Coupled Vibration Models of Drillstring

2018
Drilling is a significant constituent part in the process of the exploration and exploitation of oil and gas. Capital expenditure spent on the drilling process make up large portion of the entire cost, and so much of the reason causing this consequence depends on the unwanted vibrations of drillstring. Unwanted vibrations may cause premature failure of
Fu-shen Ren, Bao-jin Wang
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Wirl vibrations of the drillstring bottom hole assembly

Strength of Materials, 2010
The paper is focused on a problem of flexural vibrations of a rotating drillstring bottom hole assembly under the action of the friction (cutting) moment. The mechanism of self-excitation of the vibrations has been analyzed. The induced moment is shown to be nonconservative and represents the main source of dynamic instability of the system.
V. I. Gulyaev, S. N. Khudolii, E. I. Borshch   +2 more
openaire   +1 more source

Experimentally-Tuned Mathematical Model for Drillstring Vibrations

Volume 5: 6th International Conference on Multibody Systems, Nonlinear Dynamics, and Control, Parts A, B, and C, 2007
Field experience manifests that drillstring vibration is one of the major causes for a deteriorated drilling performance. It is crucial to understand the complex vibrational mechanisms experienced by a drilling system in order to better control its functional operation and improve its performance.
Y. A. Khulief, F. A. Al-Sulaiman
openaire   +1 more source

A Field Method for Controlling Drillstring Torsional Vibrations

IADC/SPE Drilling Conference, 1992
Abstract Torsional vibrations are detrimental to the life of drillstring components (1,2,3,4). Although methods of controlling them have been proposed (1,3,4), their general dependence on strain gauges to measure drillstring torque make them unsuitable for the drilling environment. In this paper we describe a new, practical, system which
Prasert Sananikone, Osamu Kamoshima, D.B. White   +2 more
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Drillstring Imaging—An Interpretation of Surface Drilling Vibrations

SPE Drilling & Completion, 1993
Summary A brief review of drillstring vibration literature is followed by the development of a model-based approach to analyze drillstring vibrations. The resulting image calculated from vibration data allows identification of interaction points between the wellbore and the drillstring. Field data examples are given.
A. K. Booer, R. J. Meehan
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Consequences and Relevance of Drillstring Vibration on Wellbore Stability

Proceedings of SPE/IADC Drilling Conference, 1999
Abstract Historically, wellbore instability problems have been mainly attributed to the physico-chemical interaction between the rock and the drilling fluid, especially when this is a water-based fluid (WBM). However, recent studies have shown that these chemical effects may be irrelevant in comparison with other energetic events which ...
Helio Santos, J. C. R. Plácido, Claudio Wolter   +2 more
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Effect of Process Damping on Longitudinal Vibrations in Drillstrings

Journal of Energy Resources Technology, 1994
This paper shows the effect of process damping—caused by the interference between the cutter and the previously cut surface—on the stability of drillstrings. The method of including process damping in the calculation of the stability diagram is outlined.
M. A. Elsayed, R. L. Wells, D. W. Dareing, K. Nagirimadugu   +3 more
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Improvements in Root-Cause Analysis of Drillstring Vibration

Journal of Petroleum Technology, 2016
This article, written by Special Publications Editor Adam Wilson, contains highlights of paper IADC/SPE 178819, “Improvements in the Root-Cause Analysis of Drillstring Vibration,” by Jeremy A. Greenwood, SPE, Halliburton, prepared for the 2016 IADC/ SPE Drilling Conference and Exhibition, Fort Worth, Texas, USA, 1–3 March.
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