| Abstract |
Aerated Drilling is a technique where compressed air is introduced into the drilling fluid circulating system to reduce the effective density of the fluid column in the wellbore annulus with final goal to allow drilling fluid and cutting circulated back to the surface. Obtaining cutting return to the surface is very important and beneficial for all function within the subsurface team i.e. drilling, earth science, and reservoir engineering. For drilling, a better hole cleaning will reduce the risk of stuck pipe and minimize drilling torque that allow to drill deeper well. Improved ROP and longer bit life are the other side benefit. For earth science, availability of cutting sample will help on formation evaluation and better geological control. For reservoir, less cutting entering feed zone will minimize formation damage which eventually results in a better production. The paper reviews the practice of using aerated mud in improving the Drilling Performance in GPO-I 2012/2013 Salak Drilling Campaign. The actual Bottom Hole Pressure (BHP) from PWD is compared to its fracture pressure and formation pressure. Understanding the important role of Pore Pressure, Fracture Pressure, and ECD in aerated drilling is however still a proving a challenge. The intent is to balance the annular and formation pressures to avoid over-gain via under-pressure that can cause a blow out, but minimal overbalance to avoid loss circulation. Proper drilling planning and optimum execution are the key factors that lead to a successful aerated drilling. |