Managed pressure drilling is defined as an adaptive drilling process used to precisely control the annular pressure profile throughout the wellbore. It provides a closed-loop circulation system in which pore pressure, formation fracture pressure, and bottom-hole pressure in wellbore are balanced and managed at surface. Drilling fluid is supplemented by surface backpressure, which can be adjusted much faster in response to downhole conditions compared with changing mud weights conventionally.
The objectives managed pressure drilling is to ascertain the downhole pressure environment limits and manage the annular hydraulic pressure profile accordingly. Managed pressure drilling aims to avoid continuous influx of formation fluids to the surface. Any influx incidental to the operation needs to be safely contained using an appropriate process.
The managed pressure drilling service market can be segmented based on type of technology, application, and region. Various types of technology of managed pressure drilling are constant bottom-hole pressure (CBHP), mud cap drilling (MCD), and return flow control drilling (RFCD). CBHP drilling refers to any technique, wherein the bottom-hole pressure remains essentially constant. Rig mud pumps are turned on and the fluid in the wellbore is circulating or when the rig mud pumps are turned off the well remains static. MCD operation consists of distinct zones, namely fluid zone, mixture zone, interface zone, and interaction zone.
RFC is drilling with a closed annulus return system (RCD) immediately under the rig floor for complete assurance of the total diversion of any rapidly developing kick. Based on application, the managed pressure drilling service market can be classified into offshore and onshore areas. Managed pressure drilling service helps save costs of drilling. It prevents mishaps occurring during drilling operations. It also helps to improve wellbore stability, improve rate of penetration while drilling, and reduce influx and losses.