Experimental investigation of the effect of axial vibration generated by pressure pulses on drilling performance

摘要

Considering the fact that improving drilling efficiency contributes to the industry success, many academic organizations, industrial research organizations and companies have invested in research that leads to better drilling experience, time wise and efficiency wise. This thesis is a research based study that aims to find new methods to improve drilling efficiency. The study investigates the effect of vibration generated using periodic pressure pulses created at the bit by a down-hole tool on the drilling efficiency, and in fact demonstrates that the technology can improve drilling efficiency. The study is based on various sets of laboratory experiments, which were conducted to characterize the functionality of a Pressure Pulses Generating (PPG) down-hole tool, and to test the effect of the down-hole tool output on actual drilling experiments. Two different setups were used to conduct the experiments in laboratory environment. In the drilling experiments synthetic rock was used as test specimens with highly controlled properties and strength. The drilling experiments were conducted at different simulated down-hole condition, including bottom hole pressures, and different fluid flow rates.udThe study also highlighted the effect of varying the drill string compliance on the overall effect of induced down-hole axial vibration. Finally the study sets base for further investigation and experiment that will be conducted using a bigger scale setup similar to land drill rigs.