Results 201 to 210 of about 175,988 (236)

Helical Buckling of Tubing Sealed in Packers

Journal of Petroleum Technology, 1962
Abstract Most gas wells and flowing oil wells are completed and treated through a string of tubing and a packer. Changes in temperature and in pressure inside or outside the tubing will:if free motion of the tubing inside the packer is permitted, increase or decrease the length of the tubing; orif free motion is ...
Arthur Lubinski, W.S. Althouse
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The Pitch of Helically Buckled Pipe

SPE/IADC Drilling Conference, 2005
Abstract The most fundamental question about helically buckled pipe is "What is the pitch?" The original development by Lubinski and Woods1 used the method of virtual work to determine a specific constant pitch. Since any constant pitch will solve the buckling equations, what is special about this solution?
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The Twist of a Helically Buckled Casing

Journal of Engineering for Industry, 1975
When a casing buckles in three dimensions, torques, as well as bending moments, are developed. Since well casing is joined with threaded collars, it is necessary to know the magnitude of the twist of the casing to evaluate the risk of buckling failure.
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New Concepts for Helical Buckling

SPE Drilling Engineering, 1988
Summary An approximate analytic solution for the helical buckling of tubing with weight has been determined. This solution has good accuracy except near the neutral point. The solution used by Lubinski to solve the helical-buckling problem is shown to be a special case of this new analytic solution. It is generally accepted that Lubinski'
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Interactions between Torque and Helical Buckling in Drilling

SPE Annual Technical Conference and Exhibition, 1995
Abstract The effects of torque on helical buckling are a concern in coiled tubing drilling. These effects are also important in conventional drilling of long horizontal wells. This paper presents theoretical models for the effects of torque on helical buckling, normal contact force, and pitch of helix in the curved well ...
X. He, G.W. Halsey, A. Kyllingstad
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Numerical Analysis of Helical Buckling

Proceedings of SPE Deep Drilling and Production Symposium, 1986
Abstract The equilibrium equations for a helically buckled tubing with weight are solved by an approximate method that produces a generalized form of Lubinski's force-pitch relationship. This new solution provides a method for evaluating the range of application of Lubinski's results.
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Analysis of the Strength of Helical Buckling Tubing String

Applied Mechanics and Materials, 2014
Deformation of helical buckling appears on tubing string under axial compressive loads, and it may even make the tubing string fail when the loads are excessively large. To make clear stress distribution and variation of helical buckling tubing string, the formulas of equivalent stresses inside and outside of the tubing string are deduced based on the ...
Da Hu Zhong, Hui Xia, Yi Hua Dou, Yin Ping Cao   +3 more
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Study of Helical Buckling of Pipes in Horizontal Wells

Proceedings of SPE Production Operations Symposium, 1993
ABSTRACT This paper studies helical buckling, and also critical (sinusoidal) buckling, of pipes (tubing and drillstring) in horizontal wells. The large frictional drag of helically buckled pipes is also studied. Helical buckling is developed from critical (sinusoidal) buckling as the axial load keeps increasing.
Jiang Wu, H. C. Juvkam-Wold
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The Twist and Shear of Helically Buckled Pipe

Proceedings of SPE/IADC Drilling Conference, 2003
Summary The effect of torque on buckling was first recognized while designing hollow propeller shafts for ships. If buckling could be caused by torque, then perhaps torque could be induced by helical buckling. This effect has not been extensively studied because the assumption has always been that the effect was too small to be of ...
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Effects of Well Deviation on Helical Buckling

SPE Drilling & Completion, 1997
ABSTRACT Current helical buckling models are valid for vertical wells, but the validity of these solutions for deviated wells was not known. This paper describes the numerical solution of the non- linear buckling equations for arbitrary well deviation.
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