这一变化被认为是以分钟为单位的，而需要几个小时来改变MW，并提供一种安全的方法来控制随后方式的进水和放血(Fredericks和Reitsma 2006)。Mark(2008)建议通过独立的井眼屏障利用来维持油井控制。许多学者认为，对于典型的MPD系统，核心势垒为防喷器旋转，二级势垒为BP本身。Donald(2004)认为，与传统方法相比，MPD技术以钻井液作为初始屏障，防喷器作为第二屏障，MPD已被证明是在某些环境下进行钻井最常用的最安全的方法。Jennifer(2003)认为，MPD的目的在于钻得尽可能接近孔隙压力，以降低动态尺度的超平衡(Saeed, Lovorn, Arne 2012)。动态超平衡的减少被许多研究者认为是在ROP的增加、喘振的减小、swab的作用、井涌的减少和井控的改善方面的贡献。动态超平衡的减小进一步降低了井内压力。
根据Moss(2009)的研究，随着压差减小，切割或破碎岩石所需的力减小，从而增加了ROP (Breyholtz et al. 2010)。然而，重要的是不能低估足够的井眼清除的重要性。为了降低井中发生的摩擦，通常要降低循环速度。提高ROP与降低循环速度的耦合会导致环空峰值脱落、阻力大、扭矩大、扭脱甚至卡管等问题。Medley(2009)认为，钻井的危害，如井筒不稳定、循环损失、差异卡钻和井涌等，通常可以通过使用MPD技术来减轻，从而大大降低与作业相关的成本。正如Colin(2010)所述，MPD技术还提供了相当强的流量测量(Breyholtz, Nygaard和Siahaan 2010)。目前常用的流量测量设备是Colin(2010)提出的科里奥利流量计。
This change is viewed to be in the terms of minutes as compared with requirements of hours to change MW and deliver a safe method of controlling the influxes as well as bleed downs of subsequent manner (Fredericks and Reitsma 2006). It is suggested by Mark (2008) that maintenance of well control is undertaken through the independent well barriers utilization. It is considered by various researchers that for typical system of MPD, the core barrier will be the BOP rotating while the barrier of secondary nature will be the BP itself. As suggested by Donald (2004), contrasting this technique with the conventional method wherein the fluid of drilling is utilized as initial barrier and BOP as second barrier, MPD has proven to be the common most secure method for undertaking drilling in some environments. According to Jennifer (2003), the MPD’s aim lies in drilling as close as possible to the pore pressure in order to lower the overbalance of dynamic scale (Saeed, Lovorn and Arne 2012). Dynamic overbalance reduction is viewed by various researchers as contribution in increment of ROP, decrement of surge, effects of swab, influx reduction and improvement of the well control. Reduction of dynamic overbalance further lowers the variable pressured within the well.
According to Moss (2009), as the differential pressure reduced, the force required to cut or break the rock is reduced which increased the ROP (Breyholtz et al. 2010). However, it is essential that the sufficient hole clearing’s significance is not underestimated. The rate of circulation is general reduced to lower the friction that takes place in well. The coupling of enhanced ROP and the lowered rate of circulation can result in issues such as annulus peak off, drag and high torque, twists off and even stuck pipe.According to Medley (2009), hazards of drilling such as instability of wellbore, circulation loss, differential sticking and kicks are the concerns which can usually be mitigated with the utilization of MPD technology resulting in considerable lowering of costs related to the operations. As per Colin (2010), technology of MPD also provided with considerably enhanced measurements of flow (Breyholtz, Nygaard and Siahaan 2010). The commonly used device of flow measurement presently is the Coriolis flow meter as suggested by Colin (2010).