Prediction of Helical / Sinusoidal Buckling

1996 ◽  
Author(s):  
H. Hishida ◽  
M. Ueno ◽  
K. Higuchi ◽  
T. Hatakeyama
Keyword(s):  
Sinusoidal Buckling

ELASTIC BUCKLING OF EXTERNALLY-PRESSURIZED IMPERFECT TOROIDAL SHELLS

2001 ◽  
Vol 01 (01) ◽  
pp. 31-45 ◽  
Author(s):  
GERARD D. GALLETLY
Keyword(s):  
Initial Imperfection ◽  
External Pressure ◽  
Elastic Buckling ◽  
Geometric Imperfections ◽  
Buckling Modes ◽  
Initial Imperfections ◽  
Numerical Studies ◽  
Initial Geometric Imperfections ◽  
Sinusoidal Buckling ◽  
Toroidal Shells

This paper summarizes the results of numerical studies into the effects of initial geometric imperfections on the elastic buckling behaviour of steel circular and elliptic toroidal shells subjected to follower-type external pressure. The types of initial imperfection studied are (a) axisymmetric localized ones and (b) sinusoidal buckling modes. The principal localized imperfections studied are (i) circular increased-radius "flat spots" and (ii) smooth dimples. The buckling pressures pcr of circular toroidal shells were not very sensitive to initial imperfections. With elliptic toroids, whether the shell was sensitive to initial imperfections or not depended on the ratio k(≡ a/b) of major to minor radii of the section. The shells on the ascending part of the pcr versus k curve behaved like circular toroidal shells, i.e. they were not sensitive to initial imperfections. However, the behaviour of elliptic toroids on the descending part of the versus k curve was very different. The numerical results quoted in the paper are for limited ranges of the geometric parameters. It would be useful to extend these ranges, to explore the effects of plasticity and to conduct model tests on imperfect steel models to verify the conclusions of the numerical studies.

The Sinusoidal Buckling Mechanical Analysis for the Coiled Tubing Based on Energy Method

2013 ◽  
Vol 477-478 ◽  
pp. 141-145
Author(s):  
Chun Sheng He ◽  
Ju Bao Liu ◽  
Qian Bei Yue ◽  
Yan Wang
Keyword(s):  
Energy Method ◽  
Counting Function ◽  
Fluid Pressure ◽  
Deformation Energy ◽  
Mechanical Analysis ◽  
Large Area ◽  
Coiled Tubing ◽  
Optimization Of Process Parameters ◽  
Hole Level ◽  
Sinusoidal Buckling

Columns are prone to sinusoidal buckling and repeated instability on the effect of drilling pressure and fluid pressure during drilling operation. The resulted large area of random contact to borehole wall would affect the drilling efficiency. It made the backreaming and loading hard and the drilling pressure low. Using energy method, taking flexural deformation energy and external potential energy of strings, hole section (slant hole, bending hole, level hole) and annular clearance etc. into consideration, derived the counting function of force that sinusoidal buckling occurred on coiled tubing when it contact with the wellbore, establishing the mechanical analysis method of calculating for sinusoidal buckling of slim lined construction roof bolt and string borehole. It proves an effective method for the applying of coiled tubing drilling pressure and the optimization of process parameters.

Sinusoidal buckling of a thin rod with connectors constrained in a torus

2014 ◽  
Vol 21 ◽  
pp. 746-756 ◽  
Author(s):  
Shaolei Wei ◽  
Linsong Cheng ◽  
Wenjun Huang
Keyword(s):  
Sinusoidal Buckling

First-Principles Finite Element Modeling of Coiled Tubing in Directional Wellbores

2011 ◽  
Author(s):  
Lance T. Hill ◽  
Deepak V. Datye
Keyword(s):  
Finite Element ◽  
Finite Element Modeling ◽  
First Principles ◽  
Drill Pipe ◽  
Oil Well ◽  
Element Modeling ◽  
Coiled Tubing ◽  
Fast Running ◽  
Sinusoidal Buckling ◽  
Helical Buckling

Coiled tubing is utilized in a variety of oil well operations. For applications such as drilling, completions, and remediation, coiled tubing offers the benefits of reduced costs, increased insertion speed, and reduced environmental impact. Coiled tubing possesses a limitation, however, in that it can buckle in service causing damage to the tube and disruption of operations. There have been numerous papers published during the last 50 years on helical buckling. Numerous fast running engineering codes have been developed to determine the onset of sinusoidal buckling, helical buckling, and lock-up of drill pipe in a wellbore, with particular emphasis on coiled tubing. We provide a methodology for evaluating the complete nonlinear mechanical behavior of coiled tubing insertion from a first-principles finite element modeling perspective. Using this approach the buckling, post-buckling, and lock-up behavior of the drill pipe can be studied. Additionally, post lock-up methods such as vibration loading and downhole lubrication can also be evaluated.

Helical Buckling of Pipes in Extended Reach and Horizontal Wells—Part 1: Preventing Helical Buckling

1993 ◽  
Vol 115 (3) ◽  
pp. 190-195 ◽  
Author(s):  
J. Wu ◽  
H. C. Juvkam-Wold ◽  
R. Lu
Keyword(s):  
Theoretical Analysis ◽  
Current Literature ◽  
Laboratory Experiments ◽  
Development Process ◽  
Theoretical Study ◽  
Horizontal Wells ◽  
Buckling Load ◽  
New Equation ◽  
Sinusoidal Buckling ◽  
Helical Buckling

This paper studies the helical buckling of pipes (drillstring and tubing) in extended reach and horizontal wells, theoretically and experimentally, resulting in new equations to correctly predict and effectively prevent the helical buckling of pipes in such wells. The theoretical study shows that the so-called helical buckling load that appears in the current literature is only the average axial load in the helical buckling development process. The laboratory experiments confirm the theoretical analysis. The new helical buckling load equations are formulated by combining the theoretical analysis and the experimental results, thereby resolving the existing assumption-and result inconsistency in the current literature. The new equation predicts the true helical buckling load to be about 1.3 times the so-called helical buckling load in the current literature, and about 1.8 times the critical buckling load that predicts the onset of sinusoidal buckling. Consequently, larger bit weights or packer setting loads can be applied to increase the drilling rate or to ensure a proper seal, before the helical buckling of the pipes can occur.

Experimental and Analytical Study of Sinusoidal Buckling in Vertical Wells

1994 ◽  
Author(s):  
J.B. Salies ◽  
J.C.S. Cunha ◽  
J.J. Azar ◽  
J.R. Soren
Keyword(s):  
Analytical Study ◽  
Vertical Wells ◽  
Sinusoidal Buckling

Analysis of Critical Buckling Loads For Tool-Jointed Drillstrings in Deviated Wellbores

2021 ◽  
Author(s):  
Nnaemeka Princewill Ohia ◽  
Stanley Toochukwu Ekwueme ◽  
Gabriel Ifeanyi Achumba ◽  
Ndubuisi Okechukwu Okereke ◽  
Ifeanyi Valerian Nwankwo ◽  
...  
Keyword(s):  
Compressive Force ◽  
Buckling Loads ◽  
Force Transfer ◽  
Open Hole ◽  
Post Buckling ◽  
Definition Of ◽  
Comparison Of The Results ◽  
Sinusoidal Buckling ◽  
Helical Buckling ◽  
Tool Joint

Abstract Excessive torque and drag, buckling and shear forces on downhole strings and tubulars are often encountered in the drilling of longer reach or deviational wells. Buckling of drillstring and BHA occurs in drillstring mainly due to high compressive forces. A point may be reached where these compressive forces rise and exceed the critical buckling loads leading to buckling of the drillstring/BHA or tubulars. This study focuses on the evaluation of the effect of tool-joint on the buckling of drillstrings for highly deviated wells. Tool-joint in pipes changes the pipes geometry in the wellbore thus affecting its hydraulics, orientation and stress distribution. A notable error will arise when straight pipe (with uniform outside diameter (OD) models are used to model pipes with end couplings and connections (such as tool joints). These errors may impact critical buckling loads, buckling initiation points, and post-buckling analysis of the pipe or BHA, thus affecting the success of drilling and completion operations. Torque and drag simulation and analysis was carried out for drillstring and BHA components in 9 5/8 in casing and 8.5 in open-hole sections to determine buckling loads. Two cases were considered; case 1 investigated the modeling and definition of buckling conditions for single straight body drillstrings and case 2 evaluated the buckling conditions for tool-jointed pipes. The result shows that buckling in tool-jointed pipes follows similar trend to that of straight body pipes with sinusoidal or lateral buckling being initiated first, and gradually progresses to helical buckling on increased axial force transfer. Furthermore, from the comparison of the results from two cases considered, it was observed that the presence tool-joint in the pipes led to a critical buckling load of 5.8% for sinusoidal buckling modes. The paper suggests that higher compressive force is needed to buckle the tool-jointed ends of the drillstring than the straight ends.

Sign in / Sign up

Export Citation Format

Share Document