Standard for Actuators and Mounting Kits for Valves

API STANDARD 6DX

SECOND EDITION, FEBRUARY 2020

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Foreword

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Contents

Page

1. Scope 1

2. Normative References 1

3. Terms, Definitions, Abbreviations, and Symbols 2

   1. Terms and Definitions 2

   2. Symbols and Abbreviated Terms 5

4. Actuator Types and Configurations and Performance 6

   1. General 6

   2. Actuator Types 6

   3. Action on Loss of Input Supply 7

   4. Quality Management System 7

5. Design 7

   1. Design Input 7

   2. Interface with Valve 10

   3. Hydraulic Fluid Requirements 10

   4. Design Basis 10

   5. Pressure-containing Parts 11

   6. Mechanically Loaded Parts 11

   7. Mounting Kit 13

   8. Lifting 14

   9. Manual Override 14

   10. Locking Devices 14

   11. Local Position Indicators 14

   12. Travel Stops 14

   13. Orientation 14

   14. Seals Preventing Water or Environmental Ingress 15

   15. Cleanliness During Assembly of Hydraulic Actuators 15

   16. Pressure Protection 15

   17. Design Documents 15

6. Sizing of Actuators 15

   1. Required Information 15

   2. Safety Factor 15

   3. Method 16

7. Instrumentation/regulation 16

   1. Torque Limiting Settings—Electric Actuators 16

   2. Torque/thrust Limiting Controls—Pneumatic/Hydraulic Actuators 16

8. Materials 19

   1. Material Specification 19

   2. Service Compatibility 19

   3. Environmental Conditions 19

   4. Composition Limits 19

   5. Bolting—Joining Pressure-containing Parts, Mechanically Loaded Parts, and Mounting Kits 20

   6. Mechanically Loaded Parts 20

   7. Plating 20

      Contents

      Page

9. Welding 20

   1. Welding of Pressure-containing Parts 20

   2. Structural Welding 21

   3. Impact Testing 21

   4. Hardness Testing 22

   5. Repair 22

10. Quality Control 23

    1. NDE and Inspection Requirements 23

    2. Measuring and Test Equipment 23

    3. Qualification of Inspection and Test Personnel 24

    4. NDE of Repairs 25

11. Final Acceptance Testing 25

    1. Pneumatic and Hydraulic Actuators 25

    2. Electric Actuators 27

    3. Actuator Functional Test 28

12. Surface Protection 28

13. Marking 29

14. Preparation for Shipment 29

15. Documentation 29

Bibliography 32

Figures

1. Relationship Between Pressure 11

2. Charpy V-notch Weld Metal (WM) Specimen Location 21

3. Charpy V-notch Heat-affected Zone (HAZ) Specimen Location 22

Tables

1. Position and Load Stops—Axial Flow Valves 16

2. Position and Load Stops—Ball Valves 17

3. Position and Load Stops—Check Valves 17

4. Position and Load Stops—Gate Valves (Expanding) 17

5. Position and Load Stops—Gate Valves (Slab) 18

6. Position and Load Stops—Plug Valves 18

7. Duration of Shell Tests 26

8. Duration of Piston and Vane Seal Tests 26

9. Marking of Pneumatic/hydraulic Actuators 29

10. Marking of Electric Actuators 29

    Contents

    Page

11. Required Documentation 30

12. Record Retention 30

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 U.S. customary (USC) and metric (SI) units. For a specific order item, unless otherwise stated, only one system of units shall be used, without combining data expressed in the other system.

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, Annex B, Rule A.

Conformance with this International Standard

A quality system applied to assist compliance with the requirements of this International Standard is typically implemented by the manufacturer. The manufacturer is responsible for conforming with all the applicable requirements of this standard. It is permissible for the purchaser to make any investigation necessary to be assured of conformance.

Standard for Actuators and Mounting Kits for Valves

1. Scope

   
   

   This standard defines the requirements for design, mechanical integrity, and sizing of actuators and related components, and is applicable to all types of electric, pneumatic, and hydraulic actuators, inclusive of mounting kit, installed on valves that conform to API Specification 6D.

   
   

   This standard is not applicable to actuators installed on control valves, valves being used for regulation, valves in subsea service, handheld powered devices, manually operated gearboxes, instrument tubing and associated fittings, and actuator control equipment.

   
   

2. Normative References

The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

API Specification 6D,1 Specification for Valves

ASME Boiler and Pressure Vessel Code,2 Section VIII, Division 1, Rules for Construction of Pressure Vessels

ASME Boiler and Pressure Vessel Code, Section VIII, Division 2, Alternative Rules, Rules for Construction of Pressure Vessels

ASME Boiler and Pressure Vessel Code, Section IX, Welding and Brazing Qualifications

ASNT ACCP-CP-1,3 ASNT Central Certification Program

ASNT SNT-TC-1A, Non-Destructive Testing

ASTM A370,4 Standard Test Methods and Definitions for Mechanical Testing of Steel Products

ASTM B733, Standard Specification for Autocatalytic (Electroless) Nickel-Phosphorus Coatings on Metal

ASTM E29, Standard Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications

AWS D1.1/D1.1M,5 Structural Welding Code — Steel

AWS QC1, Standard for AWS Certification of Welding Inspectors

EN 10204,6 Metallic products — Types of inspection documents

1 American Petroleum Institute, 200 Massachusetts Ave, NW, Washington, DC 20001, www.api.org.

2 American Society of Mechanical Engineers International, 345 East 47th Street, New York, NY 10017-2392, www.asme.org.

3 American Society for Nondestructive Testing, 4153 Arlingate Plaza, Columbus, OH 43228-0518, www.asnt.org.

4 American Society for Testing and Materials, 100 Barr Harbor Drive, West Conshohoken, PA 19428-2959, www.astm.org.

5 American Welding Society, 8669 NW 36 Street, #130, Miami, Florida 33166-6672, www.aws.org.

6 CEN, European Committee for Standardization, Central Secretariat, Rue de Stassart 36, B-1050 Brussels, Belgium, www.cen.eu.