Eventos Anais de eventos
DINAME 2017
XVII International Symposium on Dynamic Problems of Mechanics
Active control on drilling systems to reduce stick-slip
Submission Author:
Guilherme Rodrigues Sampaio de Paula , RJ
Co-Authors:
Guilherme Rodrigues Sampaio de Paula, Hans Ingo Weber
Presenter: Guilherme Rodrigues Sampaio de Paula
doi://10.26678/ABCM.DINAME2017.DIN17-0016
Abstract
Systems actuated trough a flexible shaft poses a big challenge to control strategies as the actuator is not connected directly to the end effector, causing propagation effects as well as an energy accumulation and dissipation in the shaft. This paper focus the study in one of the most investigated application of this type, the top driven drilling system used in the oil and gas industry. Usually, the drilling system is composed by a top drive linked to the drill bit trough hundreds or even thousands of meters of steel pipes. All kind of vibrations will be found: longitudinal deformations will be associated to the bit bouncing, flexional with rubbing, and torsional with stick-slip effects. A better understanding is only possible when each of these situations is carefully investigated.This paper focuses on the torsional deformation of the highly flexible string and presents two different models for the the drill string, the first is the most common single spring single damper model. The second one is a 20 DOF Lumped parameters that has the advantage of being able to consider the mass of the drill string and propagation of torsional waves on the shaft. The investigation includes the development of a test rig adequate for torsional vibrations under damping that may induce stick-slip in the system.
Keywords
Drilling, control, PID controller, stick-slip, wave propagation
