General Overview of Subsea Production Systems

API TECHNICAL REPORT 17TR13 FIRST EDITION, MARCH 2016

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Foreword

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Contents

Page

1. Scope 1

2. Normative References 1

3. Terms, Definitions, and Abbreviations 1

   1. Terms and Definitions 1

   2. Abbreviated Terms 2

4. Overall System Description 5

   1. Subsea Production or Injection System 5

   2. System Configuration 7

5. Subsea Wellhead Systems 9

   1. General 9

   2. Wellhead System Elements 9

   3. Running Tools 11

   4. Miscellaneous Equipment 11

6. Subsea Tree Systems 12

   1. General 12

   2. Vertical tree (VXT) Systems 13

   3. Horizontal Tree (HXT) Systems 26

7. Mudline Casing Suspension Systems 33

   1. General 33

   2. Conventional Mudline Suspension and Conversion Equipment 33

   3. Drill-through Mudline Suspension Equipment 34

8. Subsea Manifold and Template Systems 35

   1. General 35

   2. Well Spacer/tie-back Template 36

   3. Riser Support Template/riser Base 36

   4. Cluster Manifold 36

   5. Multiwell/manifold Template 39

   6. Well Spacer and Multiwell Template Construction 39

9. Subsea Processing (SSP) Systems 41

   1. General 41

   2. Design Considerations 41

   3. Separation 43

   4. Pressure-boosting 45

   5. Water Disposal 47

   6. Electrical Power Management 47

   7. Monitoring of SSP Systems 48

10. Production Control and Chemical Injection Systems 48

    1. General 48

    2. Fiber Optics 52

    3. Acoustic Control Systems 52

    4. Control Buoys 52

    5. Multiphase Flowmeters (MPFM) 53

    6. Sand Detectors 55

    7. Leak Detection Systems 55

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       Page

    8. High-integrity Pressure-protection Systems (HIPPS) 56

    9. Chemical Injection Systems 58

11. Flowlines and Umbilicals 58

    1. Flowline and Umbilical Components 58

    2. Flowline and Umbilical Configurations and Installation Techniques 60

    3. Flowline and Umbilical End Connections 62

12. Risers 69

    1. General 69

    2. Risers for Fixed Structures 70

    3. Risers for Floating Structures 71

    4. Production Riser Components 76

13. Well Entry and Intervention System Equipment 77

    1. General 77

    2. Completion/workover (C/WO) Riser Systems 77

    3. Light Well Intervention (LWI) Systems 82

    4. Seabed Equipment Intervention Systems 83

    5. Through-flowline (TFL) System Intervention 86

    6. Pigging 87

    7. Reeled-tubing Intervention in Flowlines 88

14. Interfaces with Downhole Equipment and Specialized Host Facility Equipment 88

    1. General 88

    2. Surface-controlled Subsurface Safety Valves (SCSSV) 89

    3. Downhole Chemical Injection Systems 90

    4. Production and Formation Sensors 90

    5. Remotely Operable Flow Control Devices 90

    6. Control and Communication Systems 90

    7. Slug-suppression/Control Equipment 91

Figures

1. Typical Elements in a Subsea Production System 6

2. Subsea Wellhead System 10

3. Vertical Xmas Tree (VXT) 14

4. Vertical Xmas Tree (VXT) Shown with Tubing Spool 15

5. Running of TH on Dual-bore Completion-workover Riser 16

6. Running of VXT on Dual-bore Completion-workover Riser 17

7. Running of TH on Dual-bore Landing String and Dual-bore Completion/workover Riser 18

8. Running of TH on Monobore Completion/workover Riser with Bore Selector 20

9. Running of TH on Monobore Completion/workover Riser and Dual-bore Landing String with Bore Selector 21

10. Running of VXT on Monobore Completion/workover Riser with Bore Selector 22

11. Concentric-type VXT 23

12. Concentric-type VXT Shown with Tubing Spool 24

13. Running of Concentric XT on Monobore Completion/workover Riser with Bore Selector 25

14. Horizontal Xmas Tree (HXT) 27

15. Horizontal Xmas Tree Running on Drill Pipe 30

16. Running of Tubing Hanger on HXT 31

17. Drill-through XT 32

18. Typical Mudline System with Wellhead Adapter for Casing Adapters Installed 34

19. Well Spacer/Support Template 37

20. Riser-support Template 38

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21. Schematic of Typical Manifold 38

22. Multiwell/Manifold Template with Production Riser 40

23. Schematic Diagram of Typical Satellite-well PCS 49

24. Spool-piece Alignment Method 64

25. Pull-in Methods 65

26. Stab-in and Hinge-over Method 66

27. Lay-away Method 68

28. Deflect-to-connect Method 69

29. Direct Vertical Connection Method 70

30. Rigid-pipe Risers 72

31. Flexible-pipe Risers 74

32. Typical Subsea Tree and Riser System 79

33. Typical HXT Workover System 80

Tables

1 Characteristics of Different Types of Control Systems 50

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Introduction

This document was generated based on information previously published in an informative annex included in API RP 17A and was last substantively updated in 2005 based on input from API Subcommittee 17 (Subsea Production Systems) technical experts. It has been removed from the API 17A annex and has been republished within this technical report. This technical report is intended to act only as a historical reference of information.

This document is not intended to inhibit a manufacturer from offering, or the Purchaser from accepting, alternativeequipment or engineering solutions for the individual application. This may be particularly applicable where there isinnovative or developing technology.

General Overview of Subsea Production Systems

1. Scope

   Subsea production systems can range in complexity from a single satellite well with a flowline linked to a fixed platform, to several wells on a template producing and transferring via subsea processing facilities to a fixed or floating facility, or directly to an onshore installation.

   
   

   The objectives of this document are:

   
   

   • to describe typical examples of the various subsystems and components that can be combined, in a variety of ways, to form complete subsea production systems;

     
     

   • to describe the interfaces with typical downhole and topsides equipment that are relevant to subsea production systems;

     
     

   • to provide some basic design guidance on various aspects of subsea production systems.

   
   

2. Normative References

   The following referenced documents are helpful for the understanding and application of this document.

   
   

   API Recommended Practice 17A, Design and Operation of Subsea Production Systems—General Requirements and Recommendations (latest edition).

   
   

3. Terms, Definitions, and Abbreviations

3.1 Terms and Definitions

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

3.1.1

barrier

Element forming part of a pressure-containing envelope that is designed to prevent unintentional flow of produced/ injected fluids, particularly to the external environment.

3.1.2

deep water

Water depth generally ranging from 610 m (2000 ft) to 1830 m (6000 ft).

NOTE Since the physical circumstances of any situation will change as a function of water depth, use of the term “deep water” implies that it may be necessary to consider design and/or technology alternatives.

3.1.3

first-end connection

Connection made at the initiation point of the flowline or umbilical installation process.

3.1.4

flowline

Production/injection line, service line, or pipeline through which fluid flows.

NOTE In this document, the term is used to describe solutions or circumstances of general nature related to a flowline.

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