Plasma channel microhole drilling technology

摘要

With growing economic and environmental pressures, oil companies seek ways to increase the oil recovery from every well. Re-entry drilling of horizontal sidetracks from existing wells and multilateral drilling for new wells are techniques which help to achieve that. However, new approaches are needed to reduce the cost and to improve efficiency of rotary drilling methods used for these purposes. This research aims to develop a new plasma channel drilling (PCD) method for drilling of small diameter holes (3.5-15 cm) for sidetrack creation and multilateral drilling. The method relies upon the use of the energy of impulse plasma discharges which are formed inside rock formation ahead of the drill position. Repeated formation of the plasma channel results in an effective and controlled drilling action. Plasma channel drills developed at Strathclyde University are able to cut clearly defined circular holes in sandstone with a speed of up to 16 cm/min. Plasma channel drilling has the potential to significantly increase the lifetime of oil wells and would dramatically reduce the cost of exploration drilling and subsurface data acquisition. PCD technology can also be a cost-effective and practical solution for other applications such as mineral mining, water boring, scale removal where micro-hole drilling is essential.