Write a 6 pages paper on managed pressure and underbalanced drilling. The economic revolution of the modern era is exclusively based on the availability of quality oil and gas products. Therefore, scientists have been working on various methods to improve the extraction procedures for fuel. Underbalanced drilling and managed pressure drilling are two of the most common drilling techniques being implemented in today’s oil and gas industry. Underbalanced drilling is opposite to conventional drilling techniques. In this technique wellbore pressure is kept lower as compared to formation fluid, this result in the smooth movement of formation fluids to the surface of the wellbore(Gala and Toralde, 2011) and helps to avoid blowouts.

Underbalanced drilling is good to be used in drilling rigs as it provides the least wear to the well with increased production rate(NW_Air, 2014), but meanwhile, this technique is expensive and unreliable. While drilling deeper in the wellbore, it is sometimes difficult to maintain an underbalanced condition and the pressure within the wellbore is increased may be as a result of increased density of soil. The boring will ultimately be shifted to an overbalanced condition and this may harm the system resulting in irreversible damage and making the oil extraction expensive. Another most common drilling technique is the modification of an overbalanced technique and is used where wellbore pressure is kept higher but is continuously monitored and maintained in order to avoid any unpleasant situation. If the wellbore pressure becomes excessively high, then it is maintained by making use of different densities of mud and formation fluids and also controlling by not generating continuous influx formation fluid to the surface of the wellbore. This method is exclusively known as managed pressure drilling as it makes use of an adaptive technique to control the balance between the wellbore and its environment(Montilva et al., 2010).