A self-exciting system for percussive–rotary drilling
thesisposted on 23.07.2018 by Andre D.L. Batako
In order to distinguish essays and pre-prints from academic theses, we have a separate category. These are often much longer text based documents than a paper.
A dynamic model for a new principle of self-excited percussive–rotary drilling is presented. The system uses the stick-slip phenomenon to generate an impact action superimposed on the drilling process. This is a strongly nonlinear mechanical system with two-degrees-of-freedom, in which friction-induced vibration is used for excitation of impacts. The model has to take account of the returning effect that the impacts have on the parameters of stick-slip motion. The model incorporates friction force as a function of sliding velocity, where the self-excitation of coupled vibration of the rotating bit and the striker tend to a steady-state periodic cycle. Dynamic coupling of vibro-impact action with the stick-slip process brings innovative adaptive features into the drilling process. [Continues.]
Loughborough University, Faculty of Engineering. British Gas Technology Research Centre.
- Mechanical, Electrical and Manufacturing Engineering