Nonlinear Dynamic Analysis of Drill String System for Horizontal Oil Well with Different Positions of Stabilizers

Abstract

For the horizontal well of petroleum drilling engineering, the horizontal section of drill string was selected as a research object. Collision and friction between drill string and well wall, displacement response on the drill bit and other boundary conditions were considered in this simulated modeling. By using finite element analysis software ANSYS, the dynamic characteristics of horizontal section of drill string were calculated and discussed. The effect of different positions of stabilizers on the vibration characteristics of drill string were studied specially. The calculated results show that the installation positions of stabilizers have remarkable effects on the dynamic characteristics of drill string. It will change the lateral vibration and whirling motion of drill string remarkably. Furthermore, the reasonably installation of the stabilizers can decrease the amplitudes of lateral vibration and transient torque. Those results may provide some guidance for the vibration analysis of drill string system.

Dynamic stability of a stepped drillstring conveying drilling fluid

“…The conventional exploitation mode of oil and gas reservoir is through the vertical well, and the studies on dynamic characteristics of the drillstring in the vertical well are the most. The influence of installation sites of stabilizers on lateral vibration of the drillstring was discussed by Zhao et al (2014) and Mongkolcheep et al (2015). Considering the damping effect of the drilling fluid, Ghasemloonia et al (2013Ghasemloonia et al ( , 2014 analyzed the coupled axial-transverse vibration of the drillstring in vibration-assisted rotary drilling, however the flow effect was not included.…”