Managed Pressure Drilling Operations—Surface Back-pressure with a Subsea Blowout Preventer

API RECOMMENDED PRACTICE 92S FIRST EDITION, SEPTEMBER 2018

Special Notes

API publications necessarily address problems of a general nature. With respect to particular circumstances, local, state, and federal laws and regulations should be reviewed.

Neither API nor any of API’s employees, subcontractors, consultants, committees, or other assignees make any warranty or representation, either express or implied, with respect to the accuracy, completeness, or usefulness of the information contained herein, or assume any liability or responsibility for any use, or the results of such use, of any information or process disclosed in this publication. Neither API nor any of API’s employees, subcontractors, consultants, or other assignees represent that use of this publication would not infringe upon privately owned rights.

API publications may be used by anyone desiring to do so. Every effort has been made by the Institute to ensure the accuracy and reliability of the data contained in them; however, the Institute makes no representation, warranty, or guarantee in connection with this publication and hereby expressly disclaims any liability or responsibility for loss or damage resulting from its use or for the violation of any authorities having jurisdiction with which this publication may conflict.

API publications are published to facilitate the broad availability of proven, sound engineering and operating practices. These publications are not intended to obviate the need for applying sound engineering judgment regarding when and where these publications should be utilized. The formulation and publication of API publications is not intended in any way to inhibit anyone from using any other practices.

Any manufacturer marking equipment or materials in conformance with the marking requirements of an API standard is solely responsible for complying with all the applicable requirements of that standard. API does not represent, warrant, or guarantee that such products do in fact conform to the applicable API standard.

All rights reserved. No part of this work may be reproduced, translated, stored in a retrieval system, or transmitted by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission from the publisher. Contact the Publisher, API Publishing Services, 1220 L Street, NW, Washington, DC 20005.

Copyright © 2018 American Petroleum Institute

Foreword

Nothing contained in any API publication is to be construed as granting any right, by implication or otherwise, for the manufacture, sale, or use of any method, apparatus, or product covered by letters patent. Neither should anything contained in the publication be construed as insuring anyone against liability for infringement of letters patent.

The verbal forms used to express the provisions in this specification are as follows:

• the term “shall” denotes a minimum requirement in order to conform to the standard;

  
  

• the term “should” denotes a recommendation or that which is advised but not required in order to conform to the standard;

  
  

• the term “may” denotes a course of action permissible within the limits of a standard;

  
  

• the term “can” is used to express possibility or capability.

This document was produced under API standardization procedures that ensure appropriate notification and participation in the developmental process and is designated as an API standard. Questions concerning the interpretation of the content of this publication or comments and questions concerning the procedures under which this publication was developed should be directed in writing to the Director of Standards, American Petroleum Institute, 1220 L Street, NW, Washington, DC 20005. Requests for permission to reproduce or translate all or any part of the material published herein should also be addressed to the director.

Generally, API standards are reviewed and revised, reaffirmed, or withdrawn at least every five years. A one-time extension of up to two years may be added to this review cycle. Status of the publication can be ascertained from the API Standards Department, telephone (202) 682-8000. A catalog of API publications and materials is published annually by API, 1220 L Street, NW, Washington, DC 20005.

Suggested revisions are invited and should be submitted to the Standards Department, API, 1220 L Street, NW, Washington, DC 20005, standards@api.org.

iii

Contents

Page

1. Scope 1

   1. General 1

   2. Installation and Use of Blowout Preventers 1

2. Normative References 1

3. Terms, Definitions, and Abbreviations 1

   1. Terms and Definitions 1

   2. Abbreviations 3

4. Managed Pressure Drilling Overview 5

   1. Managed Pressure Drilling Objectives 5

   2. Available Managed Pressure Drilling Solutions 5

   3. Candidate Selection Criteria 5

   4. Managed Pressure Drilling Components 7

   5. Well Barriers 7

5. Planning 7

   1. General 7

   2. Technical Feasibility 8

   3. Front-end Engineering Design 9

   4. Safety Studies and Reviews 10

   5. Emergency Response Plan 10

   6. Detailed Design Engineering 11

6. Equipment 12

   1. Surface Equipment 12

   2. Marine Equipment 18

   3. Control Systems 34

   4. Rig Modifications 34

   5. Rig-up, Commissioning, and Testing 36

7. Drill String 38

   1. General 38

   2. General Requirements for Drill Pipe 39

   3. General Requirements for the Bottom-hole Assembly 39

   4. Drill String Design 39

8. Drilling Fluid Considerations 40

   1. General 40

   2. Compatibility with Other Systems 40

   3. Kill Weight Fluids 40

9. Well Control and Well Integrity 41

   1. General 41

   2. Well Barrier Elements 41

   3. Managed Pressure Drilling Operations Matrix 44

   4. Contingency Plans 45

   5. Well Control Action Drills 46

   6. Use of the BOP/LMRP during Managed Pressure Drilling Operations 47

   7. Roles and Responsibilities 47

   8. Riser Gas Handling 48

      v

      Contents

      Page

10. Managed Pressure Drilling Operational Guidelines. 48

    1. General 48

    2. Training 48

    3. Drilling and Related Operations 49

    4. Wellsite Supervision 50

    5. Metocean and Environmental Considerations 50

Bibliography 52

Figures

1. Simplified Managed Pressure Drilling P&ID Diagram 18

2. Above Tension Ring System Example 25

3. Example of Below Tension Ring Installation 27

4. Example of Buckling Load Analysis Showing Interrelationship

   between Mud Weight and Tension Setting 30

5. Well Barrier Schematic Example 43

6. Example of Dynamically Positioned Watch Circles and Drift-off Curve 51

Tables

1. Example of Managed Pressure Drilling Operations Matrix 44

2. Incident Scenarios 46

3. Example of Well Control Drills 47

vi

Introduction

These guidelines (recommended practices) prepared by the IADC Underbalanced Operations and Managed Pressure Drilling (UBO/MPD) Committee, consisting of representatives from various IADC member companies, represent a composite of the practices employed by various operating companies, service companies, and drilling contractors in managed pressure drilling operations. In some cases, a reconciled composite of the various practices employed by these companies was utilized. This publication is under the jurisdiction of the American Petroleum Institute, Drilling and Production Operations Subcommittee.

Managed pressure drilling operations are being conducted with full regard for personnel safety, public safety, and preservation of the environment in diverse conditions such as urban sites, wilderness areas, ocean platforms, deep water sites, very hot barren deserts, cold weather areas, including the arctic environment and wildlife refuges. As tools and equipment continually improve and develop, the technology has been applied in many geological formations, including oil and gas reservoirs and on sour wells, thus driving the need for globally accepted standards and safe operating best practices.

Managed Pressure Drilling Operations—Surface Back-pressure with a Subsea Blowout Preventer

1. Scope

   1. General

      This document provides information for planning, installation, testing, and operation of wells drilled with surface back-pressure (SBP) managed pressure drilling (MPD). This document applies only to drilling rigs with subsea blowout preventers (BOPs).

      
      

      This document addresses situations where the total drilling operation is performed balanced or overbalanced, including both hydrostatically overbalanced (no supplemental surface pressure needed to control inflow) and hydrostatically underbalanced (supplemental surface pressure needed to control inflow) systems. For underbalanced operations refer to API 92U.

   2. Installation and Use of Blowout Preventers

      Installation, testing, and use of BOPs and associated secondary well control equipment are similar to conventional drilling operations and are not included in this publication. This equipment should only be used during routine MPD operations (e.g. seal element changeout) if an adequate risk assessment has been performed. Refer to API 53 for information regarding installation and testing of BOPs in a conventional drilling operation.

      
      

2. Normative References

   This document contains no normative references. For a list of documents associated with API 92S, see Bibliography.

   
   

3. Terms, Definitions, and Abbreviations

   1. Terms and Definitions

For the purposes of this recommended practice, the following terms and definitions apply.

3.1.1

anchor point

The depth in the wellbore that a constant annulus pressure is intended to be kept.

3.1.2

common well barrier element

Barrier element that is shared between the primary and secondary barrier envelopes.

3.1.3

distribution/buffer manifold

A manifold used to facilitate the distribution of fluids into and out of the well.

3.1.4

drilling window

Pressure range between the higher of pore/collapse pressure and fracture/fluid losses pressure.

3.1.5

equivalent circulating density ECD

Equivalent circulating density is the effective density of the circulating fluid in the wellbore resulting from the sum of the pressure imposed by the static fluid column, friction pressure, and surface back-pressure.

1