Operator and Mounting Kits for Subsea Pipeline Valves

API STANDARD 6DSSX FIRST EDITION, MARCH 2021

ERRATA 1, MAY 2021

Special Notes

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Foreword

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Contents

Page

1. Scope 1

2. Normative References 1

3. Terms, Definitions, Acronyms, Abbreviations, Symbols, and Units 3

   1. Terms and Definitions 3

   2. Acronyms, Abbreviations, Symbols, and Units 8

4. Operator Types and Configurations 9

   1. General 9

   2. Action on Loss of Supply Energy 10

   3. Actuator Types 10

   4. Actuator Configuration 10

   5. Gearboxes 10

5. Design 11

   1. Design Input 11

   2. Design Standards and Calculations 13

   3. Design Requirements 14

   4. Pressure-containing Parts 15

   5. Pressure Boundary Bolting and Tie Rod Design 15

   6. Mechanically Loaded Parts 16

   7. Springs and Spring Modules 16

   8. Mounting Kit 17

   9. Drive Trains 17

   10. Design Documents 18

   11. Sealing 19

   12. Fluid Requirements 20

   13. Compensation System 21

   14. Lubrication 24

   15. Retrievable Operators 24

   16. Operator Override 28

   17. Mechanical Advantage 29

   18. Lifting Arrangements 29

   19. Remotely Operated Tool System 31

   20. Input Interface Operation Strength 32

   21. Handwheels and Levers 33

   22. Location and Orientation 33

   23. Environmental and Operational Conditions 34

   24. Actuator Hydraulic Input 34

   25. Water Depth Performance 34

   26. Corrosion Resistant Overlay 34

   27. Cathodic Protection 34

   28. Overpressure Protection 35

   29. Hydraulic Connections 35

   30. Electrical Connections 35

   31. Wet and Dry Thermal Insulation 35

   32. Instrumentation and Accessories 35

   33. Position Indication 36

   34. Travel Stops 36

   35. Assembly Practice 37

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       Contents

       Page

6. Materials 37

   1. Material Specification 37

   2. Tensile Test Requirements 38

   3. Service Compatibility 38

   4. Cast Material 38

   5. Forged Material 38

   6. Composition Limits 38

   7. Impact Test Requirements 40

   8. Pressure Boundary Bolting 41

   9. Cathodic Protection 41

   10. Hydrogen-induced Cracking 42

   11. Heat-treating Equipment Qualification 42

7. Welding 43

   1. Welding Consumables 43

   2. Welding Procedure and Welder/Welding Operator Qualifications 43

   3. Impact Testing 44

   4. Hardness Testing 45

   5. Repairs 46

   6. Repair of Welds 46

   7. Structural Welding 46

8. Quality Control 47

   1. Conformance with Standard 47

   2. Processes Requiring Validation 47

   3. Quality Control Procedures 47

   4. NDE Requirements 47

   5. Measuring and Test Equipment 48

   6. Qualification of Personnel 49

   7. Welding Inspectors 50

   8. NDE of Repairs 50

   9. Production Material Hardness Testing on Critical Parts 50

   10. Marking, Age Control, and Storage for Nonmetallic Seals 50

9. Sizing Methodology 51

   1. Sizing Method 51

   2. Design and Sizing Output Data 52

10. Testing 53

    1. Validation 53

    2. Effect of Changes in Product 54

    3. Factory Acceptance Test 54

    4. Certification 58

11. Surface Protection 58

12. Marking 58

13. Preparation for Shipment 59

14. Documentation 60

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    Contents

    Page

    1. Provided to Purchaser 60

    2. Documentation Provided with the Operator 60

Annex A (informative) Optional Documentation 61

Annex B (normative) Purchasing Guidelines 62

Annex C (normative) Record Retention 64

Annex D (informative) Design Validation—Actuator 65

Annex E (informative) Design Validation—Gearbox 74

Annex F (informative) Hyperbaric Validation Testing 81

Annex G (normative) Requirements for Nondestructive Examination 84

Annex H (informative) Castings and Forgings 89

Annex I (normative) Qualification of Heat-treating Equipment 90

Bibliography 93

Figures

1. Relationship Between Design, Rated and Supply Pressures 14

2. Retrievable Actuator Types 25

3. Part-turn Retrievable Operator Terminology 26

4. Type 1 Lifting 30

5. Type 2 Lifting 30

6. Type 3 Lifting 31

7. Handwheel Interface 33

8. Charpy V-notch Weld Metal Specimen Location 45

9. Charpy V-notch Heat-affected Zone Specimen Location 45

D.1 Test Procedure for Pressure Temperature Cycle 72

E.1 Test Procedure for Temperature Cycle 80

1. Temperature Sensor Location—Rectangular Furnace (Working Zone) 91

2. Temperature Sensor Locations—Cylindrical Furnace (Working Zone) 91

Tables

1. Description and Functionality of Mechanical Override Systems 28

2. Handwheel Interface Applied Forces 33

3. Minimum V-notch Impact Requirements for Carbon and Low-alloy Steels (Full-size Specimen) 40

4. Minimum V-notch Impact Requirements for Duplex and Super Duplex Stainless Steel (Full-size Specimen) 40

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   Contents

   Page

5. Chemical Composition of Nickel-based Alloy UNS N06625 44

6. Marking of Electric Actuators 59

7. Marking of Hydraulic Actuators 59

8. Marking of Gearbox 59

B.1 Actuator Data Sheet 62

C.1 Record Retention 64

D.1 Design Validation for Actuator 68

E.1 Design Validation for Gearbox 77

F.1 Hyperbaric Qualification Test 81

1. NDE Requirements 87

2. Extent, Method, and Acceptance Criteria of NDE/Item Examination Code 87

viii

Introduction

It is necessary that users of this document be aware that further or differing requirements can be needed for individual applications. This document is not intended to inhibit a vendor from offering or the purchaser from accepting alternative equipment or engineering solutions for the individual application. This can be particularly applicable where there is innovative or developing technology. Where an alternative is offered, it is the responsibility of the vendor to identify any variations from this document and provide details.

Units of measurement

In this specification, data are expressed in both SI and USC units.

Rounding

Except as otherwise required by this specification, to determine conformance with the specified requirements, observed or calculated values are rounded to the nearest unit in the last right-hand place of figures used in expressing the limiting value, in accordance with the rounding method of ASTM E29 or ISO 80000–1.

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Operator and Mounting Kits for Subsea Pipeline Valves

1. Scope

   
   

   This standard defines the requirements for design, mechanical integrity, and sizing of operators and related components used on subsea pipeline valves that conform to API Specification 6DSS.

   
   

   This standard is applicable to the following:

   
   

   • electric actuators;

     
     

   • electro-hydraulic actuators;

     
     

   • hydraulic actuators;

     
     

   • actuator override systems;

     
     

   • diver and remotely operated tool (ROT)-operated gearboxes;

     
     

   • other actuators, by agreement;

     
     

   • mounting kit;

     
     

   • pressure and volume compensation and associated systems;

     
     

   • pressure caps;

     
     

   • protection covers; electrohydraulic

     
     

   • position indication systems.

     
     

     This standard is not applicable to the following:

     
     

   • manual or powered torque tools not permanently mounted;

     
     

   • actuator control system equipment/components;

     
     

   • remote-located units.

   
   

2. Normative References

The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any addenda) applies.

API Specification 6DSS, Specification for Subsea Pipeline Valves

API Specification 17D, Design and Operation of Subsea Production System—Subsea Wellhead and Tree Equipment

API Recommended Practice 17H, Remotely Operated Tools and Interfaces on Subsea Production Systems

API Recommended Practice 17U, Recommended Practice for Wet and Dry Thermal Insulation of Subsea Flowlines and Equipment

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