Advanced MPD Applications: Beyond CBHP

Managed Pressure Drilling (MPD) is an established tool within the drilling industry. The most common application for MPD is maintaining the Constant Bottom Hole Pressure (CBHP) approach to enable drilling in narrow windows. Beyond this core function, there is a side benefit from using MPD in its Early Kick and Loss Detection (EKLD) capabilities.

However, MPD is applied in a range of operations where maintaining CBHP is not the primary objective, including applications such as Mud Cap Drilling (MCD) and Influx Management. In this article, we’ll explore these methods and other usage areas of MPD going beyond the CBHP approach. 

 

Influx Management

Influx Management is one of the most common MPD applications after the CBHP approach. Particularly in deepwater operations, where conventional well control methods are challenging due to added friction from the long choke lines. With MPD, a riser closure device such as an Annular (Single or Dual) or Active Closure Device is used in combination with a surface choke or a subsea pump to circulate the influx out of the well in a controlled manner.

Learn more about how EC-Drill® Dual MPD helps you with Influx Management here.

Mud Cap Drilling

Mud Cap Drilling (MCD) is applied when drilling into loss zones where returns to surface cannot be maintained. MPD offers two methods for Mud Cap Drilling: Pressurized Mud Cap Drilling (PMCD) and Controlled Mud Cap Drilling (CMCD).

There are several advantages to using MPD in these conditions. MPD provides continuous monitoring of annular pressure, and provides pressure management. This reduces uncertainty compared to conventional MCD, where visibility into downhole conditions is limited. It also lowers the risk of gas migrating up the well and reduces overall mud consumption. 

Well Design

Improving and simplifying well design is particularly relevant in deepwater operations. The hydrostatic pressure profile from  the rig to seabed causes at misalignment with the available pressure window. Combined with narrow margins, this can lead to additional sections and a more complex well design, sometimes requiring non-standard hole and casing sizes. 

By lowering the fluid level in the riser, the hydrostatic profile aligns better with the operating window. This approach, known as the Dual Gradient Effect, enables the elimination of casings or liners in about 80% of deepwater wells drilled with the Controlled Mud Level (CML).

Dual Gradient Pressure Profile

The Dual Gradient Effect shifts the mud pressure profile closer to the optimal drilling window, reducing casing requirements and extending the achievable drilling depth in deepwater operations.

Read more: 11 Things All Drilling and Completion Engineers Need to Know About MPD

Depletion

In mature fields, depletion can limit access to remaining parts of the reservoir. This challenge can be addressed with CML, by lowering the fluid level in line with the actual degree of depletion. In several fields, CML has enabled continued drilling and even extended well reach to access reserves otherwise inaccessible.  

In some operations, this has been achieved without applying CBHP and conducting pressure adjustments. The fluid level is kept constant during drilling and connections, and is like conventional drilling. This is particularly relevant in fields where low-density fluids create too high hydrostatic pressure.

Completion

The use of MPD in completion operations is a more recent development. In particular, applying CML in open hole gravel pack completions has shown a significant increase in production rate and life-span of the wells. With CML the completions have achieved a full screen out with the Beta-wave compared to former results when the gravel packing ended when losses incurred.

CML is increasingly applied in completion to support a more consistent execution and improved production outcomes.

Insurance

In operations involving high-risk formations – either due to potential losses or anticipated pressure variations – MPD serves as a critical tool. In these cases, MPD  can be applied to adjust bottom-hole pressure in line with actual well conditions. This is often done by altering the CBHP setpoint. 

 In addition, Early Kick and Loss Detection (EKLD) improves the ability to identify and respond to influxes and loss events at an earlier stage. Riser Gas Handling (RGH) can also be included to improve safety.

Check out: What Are Undrillable Wells in 2025 and How to Make Them Drillable 

Conclusion

The development of MPD has expanded beyond maintaining CBHP in wells with narrow margins. Today, it is increasingly applied to support other objectives, such as simplifying well design, enabling drilling in depleted fields, and improving completion operations. In many cases, several of these applications are combined within the same well.

In addition to the primary use cases, MPD also provides operational benefits such as more efficient tripping, reduced need for fluid displacement, and shorter exposure time for the formation.

Snorre Lutnes

Snorre works as a Technical Sales Manager for Enhanced Drilling. He has worked within drilling for 20 years primarily with Drilling fluids and MPD. He started his career offshore as a mud engineer before assuming project management roles onshore. After working internationally for a decade, he has returned to Norway moving from an operational role to focusing more on technical sales.