Intro to Manage Pressure DrillingRAO Mubarak Alimubarik.ali43@yahoo.cominternational member of SPE 4353073

Introduction to Manage Pressure Drilling (MPD)

Drilling operations have always been challenging, wells are getting deeper, temperature and pressures are getting higher, and the industry is starting to focus on more remote and complex reservoirs such as in the arctic regions. Proper procedures for remedial actions are essential to keep drilling risks controlled and minimized. Managed Pressure Drilling (MPD) is a drilling process that enables accurate control of the wellbore pressure faster than by conventional methods.

Objectives

The objectives are to ascertain the down-hole pressure environment limits and to manage the annular hydraulic pressure profile accordingly. The intention of MPD is to avoid continuous influx of formation fluids to the surface. Any influx incidental to the operation will be safely contained using an appropriate process”.

Definition of MPD

MPD is defined by a subcommittee of the International Association of Drilling Contractors (IADC) as;

“An adaptive drilling process used to precisely control the annular pressure profile throughout the wellbore”.

Managed Pressure Drilling (MPD) is a drilling process that enables accurate control of the pressure faster than by conventional methods. Pressure variations can thereby be reduced, influx and losses handled at an early stage thereby reducing the subsequent challenges, and wellbore stability can be improved.

Uses

1. MPD allows for drilling into narrow pressure margins in a safer and more cost effective manner while mitigating drilling hazards and thereby reducing Non--‐Productive Time (NPT).

2. MPD can be used for specific purposes such as drilling into depleted reservoirs, narrow Mud-Weight (MW) windows or sections with massive losses where other drilling methods are inadequate.

Advantages

Drill through Narrow  Drilling Windows

No loss in Bottom Hole Pressure during  connections

Increased visibility of  unfavorable well  conditions

Greater control of down bottom hole pressure

Early kick detection

Different Managed Pressure Drilling Techniques

The four main MPD variations and providers are the following1. Constant Bottom Hole Pressure Profile [Schlumberger, Weatherford,

Halliburton]2. Mud Cap Drilling [Schlumberger, Weatherford, Halliburton]3. Dual Gradient (with and without a riser) [AGR, Clean Drill, Reel Well]4. Return Flow Control method

1. Constant Bottom Hole Pressure (CBHP)

CBHP is a MPD method whereas the annular pressure is kept close to constant at a given depth. The method is based on maintaining control of the annular back pressure.Objective: The objective for this method is to eliminate cycles of kicks/losses that are common in deep wells where fracture gradient are close to the pore pressure.

2. Mud Cap Drilling

Mud cap drilling is employed when normal techniques have difficulties to maintain circulation. To prevent and control kicks and lost circulation while drilling in fractured or layered (different pressures) formations, drilling fluid together with water and cuttings are pumped into the wellbore and drill pipe.

3. Dual Gradient (with and without a riser)

Dual Gradient Drilling is an MPD technique that employs two different annulus fluid gradients to find a closer match to the natural pressure regime; one above the seabed, another beneath.

The Objective is to reduce formation damage and the related fluid losses when drilling deep formations with low‐fracture gradients (eliminating mud density changes).

4. Return Flow Control Drilling (RFCD)

Return through Flow Control (RFC) Drilling is a MPD method that reduces risks from drilling fluid, hazardous gases and well control incidents to the personnel and the environment.

The objective of this method is to focus on RFCD primarily.

Thank you……….