Stress-strain state of a drill string in well sections with “dog-legs”
Keywords:
a drill string, a flexible beam, a stress-strain state, “dog-leg” of a well, three-dimensional elastic line.Abstract
During the research a drill string was simulated by a flexible beam. The flexible beam has a 3D deformation under external loadings. The system of vector differential equations of equilibrium is used for analysis of the stress-strain state. The mathematical model takes into consideration a body weight and stiffness of a drill string, axial force, torsional moment and reactions of a hole wall.
The deformation of a drill string elastic line with external diameter of 127 mm in a well “dog-leg” was analyzed in real operational conditions using the developed method. The author obtained the function of a drill string elastic line in 3D coordinate system. There were drawn the diagrams of normal stresses of bending around basic axes of inertia of a drill string cross-section. It is also noticed that the “dog-leg” increases these stresses twice.
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[2] Adly, E & Staysko, B 2007, “Rotary steerable system technology case studies in the Canadian foothills: A challenging drilling environment”, World Oil, November, pp. 75 – 80.
[3] Israel, R & Aburto, M 2008, “Drilling through salt”, Offshore engineer, June, pp. 55 – 58.
[4] Riyami, M Edwards, J Vache, E Ojiduma, O Johnson, S & Darwish, W 2008, “Operator finds cost-effective rotary steerable applications in Oman’s low-cost environments”, Drilling contractor, July / August, pp. 54 – 62
[5] Hsieh, L 2010, “Rotary steerables”, Drilling contractor, March / April, pp. 18 – 26.
[6] Vuds, G, Lubinskij, A 1960, Iskrivlenie skvazhin pri burenii, GOSTOPTEHIZDAT, Moscow.
[7] Janturin, RA & Janturin ASh 2006 “Naddolotnye kalibratory dlja jekscentrichnogo smeshhenija niza buril'nogo instrumenta povyshennoj ustojchivosti k vlijaniju gornogeologicheskih uslovij provodki skvazhin”, Stroitel'stvoneftjanyh i gazovyh skvazhin na sushe i na more, no. 7, pp. 12–17.
[8] Gulyayev, VI Gaidaichuk, VV & Solovjov, IL 2009, “The buckling of elongated rotation drill strings”,Journal ofPetroleum Science and Engineering, no. 67, pp. 140 – 148.
[9] Svetlickij, VA 1987, Mehanika sterzhnej: Ucheb. dlja vtuzov. Statika, Vysshaja shkola, Moscow.
[10] Kalinin, AG Nikitin, BA Solodkij, KM 1997, Burenie naklonnyh i gorizontal'nyh skvazhin: Spravochnik, Nedra, Moscow.
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