Abstract
Drill string vibrations are a significant concern during drilling operations, and are a common cause of downhole tool failures and decreases in drilling efficiency. Drill string vibrations are typically categorized in three ways: axial (the drill string is vibrating along the axis of drilling), lateral (the drill string is vibrating perpendicular to the axis of drilling), and torsional (the rotational speed of the drill string is varying along the axis of rotation).
If applied correctly, the use of low elastic modulus and low density materials in a complex system will dampen vibrations. This hypothesis is confirmed through the use of multiple software simulations including an ABAQUS Finite Element Analysis (FEA) model and an MSC Adams multi-body dynamics model.
The simulations pointed to the conclusion that including sections of aluminum drill pipe into the drill string will dampen drill string vibrations (Dziekonski, 2017). The low elastic modulus and density of aluminum reduce both the duration and severity of torsional vibrations in a stick slip type dysfunction. The reduction in severity of uncontrolled torsional oscillations will reduce the additional strain on threaded connections throughout the bottom hole assembly and drill string, as well as the impact caused by lateral vibrations, and the amplitude of axial vibrations. This overall reduction in vibrations can be used to increase the life of sensitive downhole components and increase the efficiency of drilling operations.
