The paper will discuss the processes, methods, factors and parameters utilized to evaluate potential candidates using a defined process and simulation methods for the application of Managed-Pressure Drilling (MPD) technology in well construction operations. The use of MPD technologies can influence many wellbore pressure-related drilling challenges, including lost circulation, kicks, wellbore ballooning, tight pore pressure (PP)/fracture pressure (FP) margins, close tolerance casing programs, wellbore stability problems, shallow water/gas flows, slow ROP, etc. These techniquesmay also enable future well programs that are currently thought to be conventionally ‘undesignable’ with single gradient mud systems.
Potential drilling efficiency benefits may include improved HSE, drilling with less Non-Productive Time (NPT) or trouble time, improved wellbore stability, reduced mud losses, improved ROP performance and extension of casing seats/fewer casing strings
A process has been applied to evaluate the economics of candidate wells for the use of MPD. This evaluation has included the use of a probabilistic Monte Carlo simulation of the potential results of the use of MPD and takes into account time dependent, cost dependent and performance related factors. The use of other technologies such as wellbore strengthening or wellbore stability technologies in conjunction with MPD can also be modeled to look at the overall benefit of use of all applied technologies within the well construction process.
The significance of MPD, in the face of increasing well construction costs around the world, is that these techniques may allow step-change reductions in drilling duration and associated costs. More importantly, MPD may allow the drilling of wells that cannot be drilled with conventional drilling processes. MPD technologies may also allow improved well performance through a more efficientcompletion size and an increase in recoverable reserves.
Managed-Pressure Drilling (MPD) is an advanced form of primary well control that many times employs a closed and pressurizable drilling fluid system that allows potentially greater and more precise control of the annular wellbore pressure profiles than mud weight and pump rate adjustments alone. The primary objective of MPD is to optimize drilling processes by decreasing non-productive time (NPT) and mitigating drilling hazards in the well construction process.1
The IADC Managed Pressure Drilling and Underbalanced Operations Committee defines Managed-Pressure Drilling as: ‘MPD is an adaptive drilling process used to more precisely control the annular pressure profile throughout the wellbore. The objectives are to ascertain the downhole pressure environment limits and to manage the annular hydraulic ressure profile accordingly.’2 MPD processes employ a collection of tools and techniques which may mitigate the risks and costs associated with drilling wells that have narrow downhole environmental limits by proactively managing the annular hydraulic pressure profile.