Managed Pressure Drilling

Bill Rehm, Jerome Schubert, Arash Haghshenas, Jim Hughes, Amir Saman Paknejad

• Publisher: Gulf Publishing Company
• Year: 2013
• Print ISBN: 9781933762241
• eBook ISBN: 9780127999876
• Topic: Naturwissenschaften
• Subtopic: Geologie & Geowissenschaften

With extraction out of depleted wells more important than ever, this new and developing technology is literally changing drilling engineering for future generations. Never before published in book form, these cutting-edge technologies and the processes that surround them are explained in easy-tounderstand language, complete with worked examples, problems and solutions. This volume is invaluable as a textbook for both the engineering student and the veteran engineer who needs to keep up with changing technology.

CHAPTER ONE

The Why and Basic Principles of Managed Well-Bore Pressure

Arash Haghshenas, Texas A&M University

Amir Saman Paknejad, Texas A&M University

Bill Rehm, Drilling Consultant and Jerome Schubert, Texas A&M University

About This Chapter

This chapter is an introduction to the content of the book. In this chapter, managed pressure drilling is defined to clearly state the book’s objective. Then, the benefits of managed pressure drilling are explained. At the end, basic well control and pressure regimes in the well bore are defined to provide the background required for understanding the other chapters.

1.1 Introduction to Managed Pressure Drilling and Some Definitions

Managed pressure drilling (MPD), as a discipline or drilling technique, is the result of the high costs of nonproductive time (NPT) caused by the close proximity between pore pressure and fracture pressure. This problem is often associated with marine drilling in soft sediments, but it also can be a problem in land drilling.

MPD is a general description of methods for well-bore-pressure management. MPD includes a number of ideas that describe techniques and equipment developed to limit well kicks, lost circulation, and differential pressure sticking, in an effort to reduce the number of additional casing strings required to reach total depth (TD).

The field of well-bore pressure management has broad application in the drilling industry and provides solutions to problems in

• Extending casing points to limit the total number of casing strings and the subsequent hole size reduction.

• Limiting the NPT associated with differentially stuck pipe.

• Avoiding the lost circulation–well kick sequence.

• Limiting lost circulation.

• Drilling with total lost returns.

• Increasing the penetration rate.

• Deepwater drilling with lost circulation and water flows.

The International Association of Drilling Contractors (IADC) Subcommittee on Underbalanced and Balanced Pressure Drilling has made the following formal definition ofmanaged pressure drilling: “Managed Pressure Drilling (MPD) is an adaptive drilling process used to more precisely control the annular pressure profile throughout the well bore. The objectives are to ascertain the downhole pressure environment limits and to manage the annular hydraulic pressure profile accordingly. This may include the control of back pressure by using a closed and pressurized mud returns system, downhole annular pump or other such mechanical devices. Managed Pressure Drilling generally will avoid flow into the well bore.”

Not in the formal definition but implied is that this drilling method uses a single-phase drilling fluid treated to produce minimal flowing friction losses.

“MPD’s ability to dramatically reduce NPT in today’s high rig rate market makes it a technology that demands consideration in any drilling or development program. MPD helps manage the problems of massive losses associated with drilling fractured andkarstic carbonate reservoirs. It also reduces ECD [equivalent circulating density] problems when drilling extended reach wells and wells with narrow margins between formation breakdown and well kicks. In long horizontal sections, reducing ECD helps mitigate the impact of drilling fluid induced impairment that is amplified by high overbalance.” The definition is unique (an adaptive process) in that it proposes that the drilling plan is not only changeable but will change as the conditions in the well bore change.

The basic techniques covered under MPD are

• Constant bottom-hole pressure (CBHP) is the term generally used to describe actions taken to correct or reduce the effect of circulating friction loss or equivalent circulating density (ECD) in an effort to stay within the limits imposed by the pore pressure and fracture pressure.

• Pressurized mud-cap drilling (PMCD) refers to drilling without returns to the surface and with a full annular fluid column maintained above a formation that is taking injected fluid and drilled cu...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• Inside Front Cover
• Preface
• Contributors
• List of Abbreviations
• Chapter 1: The Why and Basic Principles of Managed Well-Bore Pressure
• Chapter 2: Situational Problems in MPD
• Chapter 3: Constant Bottom-Hole Pressure with Pressure as a Primary Control
• Chapter 4: MPD with Flow Measurement as the Primary Control
• Chapter 5: Continuous Circulation System
• Chapter 6: A Simplified Approach to MPD
• Chapter 7: Mud Cap Drilling
• Chapter 8: Dual-Gradient Drilling
• Chapter 9: Equipment Common to MPD Operations
• Chapter 10: MPD Candidate Selection
• APPENDIX A: Rock Mechanics
• APPENDIX B: Rheology
• APPENDIX C: Useful Conversion Factors
• APPENDIX D: IADC Well Classification System for Underbalanced Operations and Managed Pressure Drilling
• APPENDIX E: IADC Underbalanced and Managed Pressure Drilling Guidelines—HSE Planning Guidelines
• IADC UB and MPD Glossary
• Index