What is MPD?
What is MPD?
Managed Pressure Drilling – general term for controlling the mud circulation to optimize the bottom-hole pressure.
It’s the bottom one that makes most sense to anyone in the oil industry. Yet although the process has been around for quite some time, it is older than any of the rigs that use it, the term still manages to confuse, or at the very least cloud the mind of those in the industry who don’t use it in their daily work.
So we asked someone who knows, Martin Brand an instructor at Maersk Training in Houston, the five classic questions, what, why, how, where and when.
What Is MPD?
MPD, or Managed Pressure Drilling, is the use of specialized equipment (which can include such items as a Rotating Control Device, additional choke manifold, drill string check valves and fluid/solids control equipment among others) to control the pressure in a well being drilled. Some is positioned beneath the rig floor in the drill string and fluid return system, whilst other pieces can be located on deck. As a result it can help prevent catastrophic well control incidents.
Why Is MPD Used?
MPD is used for various reasons. It has the proven ability to make the drilling operation (an inherently dangerous process) safer, more efficient and cost effective. It allows for closer monitoring of the well and more accurate detection of any anomalies encountered and therefore enhanced response capabilities.
How Is MPD Used?
Managed Pressure Drilling relies heavily on the use of a Rotating Control Device (RCD), which is a major component in providing a closed, pressurised system. This allows for a constant bottom-hole pressure to be applied and also ensures much greater control over fluids flowing in and out of the well. Volume control is a major component of well control alongside keeping the bottom-hole pressure constant (equal to, or slightly greater than formation pressure).
Where Is MPD Used?
MPD is available on all rig types, from Land Rigs, Jack Up Rigs, Tender Rigs, Semi-Submersibles (DP / Moored) and Dynamically Positioned Drill Ships.
When Is MPD Used?
MPD is becoming more common place, and in some examples, a necessity, to meet the increasing demands and challenges of the drilling industry, both onshore and offshore.
It can be extremely useful if the well has very tight margins between letting in an influx (kick) or breaking down the formation, has a high risk of flowing due to the well conditions, or we are likely to experience problems such as differential sticking.