Managed Pressure Drilling (MPD) — High Level Operations & Best Practices
1. Pre-Job Planning & Engineering
1.1. Pressure-Margin Study and Feasibility Review
Perform a pore-pressure and fracture-gradient assessment to confirm the safe drilling window.
Model MPD options (back-pressure, mud density, and fluid-level control) to determine which method can best maintain bottom-hole pressure within safe limits.
Simulate kick and loss scenarios to understand how the well will respond under various conditions and confirm tolerance levels.
1.2. Define MPD Objectives
Set clear, measurable pressure-control goals such as:
Target bottom-hole pressure band, including pump-off and transient conditions.
Influx and losses detection thresholds.
Allowable ECD variation during different drilling activities.
Escalation criteria for transitioning to conventional well control.
Prepare an MPD Operations Matrix that outlines actions for no-influx, minor influx, and well-control escalation scenarios.
1.3. Selection of MPD Technique
Evaluate and select the most suitable MPD approach:
Constant Bottom-Hole Pressure / Surface Back-Pressure (CBHP/SBP)
Pressurized Mud Cap Drilling (PMCD) / Mud Cap Drilling (MCD)
Controlled Mud Level / Controlled Mud Cap (CML / CMC)
Continuous circulation methods
Dual-Gradient Drilling (DGD)
Note that Underbalanced Drilling (UBD) is not MPD; UBD intentionally runs below pore pressure, while MPD maintains a controlled pressure above or at balance.
Base the selection on formation risk, wellbore stability needs, reservoir sensitivity, and operational constraints.
1.4. Risk Assessment and HSE Planning
Conduct formal hazard studies such as HAZID, HAZOP, or FMEA before operations begin.
Prepare contingency procedures for influx, losses, and combined events.
Apply structured Management of Change (MOC) for any deviations.
After the job, perform a lessons-learned review and use the findings to improve future risk assessments.
1.5. Competency and Training
Assign trained and accredited personnel for MPD roles (driller, MPD operator, supervisor).
Ensure all involved staff understand MPD theory, equipment operation, transition to well control, and emergency procedures.
Regularly refresh training as procedures and equipment evolve.
1.6. Equipment Planning
Prepare a comprehensive MPD equipment list, including RCDs, choke manifolds, pressure/flow sensors, flowlines, NRVs, and control systems.
Verify that all equipment is rated for expected pressures, temperatures, and flow conditions.
Maintain redundancy for critical items such as sensors, control modules, and spare RCD sealing elements.
2. Rig-Up and Commissioning
2.1. System Testing and Verification
Pressure-test the MPD choke manifold, valves, RCD, flowlines, and high-pressure hoses before drilling.
Review P&ID and PFD drawings to confirm correct installation and flow direction.
Function-test the MPD control system, including automatic choke control, alarms, interlocks, and E-stop.
2.2. Gas-Handling and Safety Systems
Verify that gas separation and flare/vent systems are capable of handling expected gas volumes.
Ensure pressure relief valves are sized correctly and reserved strictly as last-resort devices.
Confirm that remote isolation valves, shutdown systems, and communication channels (flare notifications, evacuation plans) are functioning properly.
For deepwater wells, follow riser-gas handling practices to manage any gas in the marine riser safely.
3. Start-Up and Baseline Operations
3.1. Establishing Instrument Baselines
Zero all pressure, flow, and level sensors.
Circulate at known rates to confirm baseline flow behavior without back-pressure.
3.2. Perform Baseline Tests
Conduct static pressure checks and compare the readings to hydraulic modeling results.
Run a controlled circulation test to record ECD and annular pressures.
Perform leak-down and hold tests to confirm system integrity.
Test choke responsiveness under both manual and automatic modes.
Simulate pump-off conditions to observe pressure transients and confirm control actions.
3.3. Log and Calibrate
Record baseline pressure, flow, and ECD data.
Use actual readings to refine hydraulic models and update the safe operating window.
4. MPD Drilling Mode (Normal Operations)
4.1. Control Logic and System Alarms
Set up automated pressure control with defined alarm limits and clear manual-override paths.
Confirm control transitions (automatic ↔ manual) are understood by the rig crew.
Test fallback modes and interlocks before starting MPD drilling.
4.2. Continuous Monitoring
Track real-time pressure and flow trends along with drilling parameters such as ROP, pipe movement, and toolface changes.
Look for any indications of influx (unexpected pressure/flow increase) or losses (pressure decrease, flow drop).
4.3. Communication Protocols
Maintain continuous communication between the driller, MPD operator, and site leadership.
Hold routine briefings on system performance, alarms, and ongoing pressure conditions.
5. Tripping and Casing Operations
5.1. Tripping Practices
Follow swab/surge modeling results to determine safe tripping speeds and back-pressure adjustments.
Use a depth-based back-pressure set-point table and adjust it continuously as the string moves.
Pre-charge lines if necessary to reduce pressure fluctuations during pipe movement.
Control pump and choke adjustments during connections, break-in, and pump-off.
5.2. Flow-Balance Monitoring
Monitor flow-in versus flow-out carefully during all tripping activities.
Investigate any imbalance promptly using flow checks or piston tool procedures.
6. Influx (Kick) Management
6.1. Early Detection and Response
React to early influx signs with minor, controlled adjustments in surface back-pressure.
Maintain the target BHP to prevent unwanted gas expansion.
Follow the approved MPD well-control sequence and predefined thresholds for escalation.
6.2. Transition to Conventional Kill (If Required)
Shift to conventional well control if MPD cannot safely maintain BHP.
Ensure kill-weight fluid is available and compatible with MPD equipment.
Prepare gas-handling and separation systems for potential increased volumes.
6.3. Documentation
Record pressures, flows, timing, and choke adjustments throughout the event.
Report the incident in accordance with the company's well-control and HSE requirements.
7. Losses and Mud-Cap Operations
7.1. Contingency Activation
Activate PMCD, MCD, CML, or CMC procedures if losses cannot be managed through standard means.
Confirm that all valves, flow paths, and control systems for mud-cap operations are ready.
Ensure surface systems can manage reduced or zero returns.
7.2. Safety and Regulatory Compliance
Verify regulatory approvals for mud-cap operations and ensure compliance with environmental and containment requirements.
Conduct crew drills for MPD-to-mud-cap transitions before entering loss-prone zones.
8. Post-Job Review and Continuous Improvement
8.1. Data Quality Control
Review all recorded MPD data for accuracy, sensor drift, and correct time alignment.
Compare actual well behavior against modeling results.
8.2. Model and Procedure Updates
Update hydraulic models using real-time data.
Adjust alarm set-points, thresholds, and control strategies based on lessons learned.
8.3. Incident Review
Investigate any deviations, control failures, or significant events.
Document root causes, corrective actions, and recommendations.
8.4. Training and Procedure Revision
Update MPD procedure manuals, operations matrices, and checklists.
Retrain personnel to ensure they understand revised processes.
8.5. Continuous Improvement
Close out action items through the HSE management system.
Share key learnings within the organization and with the relevant technical groups.