Managed Pressure Drilling
Managed Pressure Drilling is often described as a collection of techniques separate from UBD. However, both UBD and MPD strive to achieve the same goal- management of pressure profile. While UBD has the goal of enhancing reservoir value through the reduction of formation damage, Managed Pressure Drilling is more specifically a drilling enabling technique. Managed Pressure drilling encompasses all techniques that actively seek to control the pressure in the openhole, while aiming to prevent influx from the reservoir, or hydrocarbon returns to surface. The key drivers for MPD are:
• Drilling in regimes with narrow pore-pressure and frac-pressure margins.
• Drilling in formations with widely varying pressures, for example, when some depleted layers are exposed while drilling higher pressure layers.
• Extending the casing setting depth
• Reducing drilling problems
Managed pressure drilling operations require as much design effort as UBD operations. Well control considerations are critical.