Design Calculations for Pressure-containing Equipment

API STANDARD 6X

SECOND EDITION, FEBRUARY 2019

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Foreword

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Contents

Page

1. Scope 1

2. Normative References 1

3. Terms, Definitions, and Symbols 1

   1. Terms and Definitions 1

   2. Symbols 2

4. Failure Modes 3

   1. Application 3

   2. Protection Against Plastic Collapse 3

   3. Protection Against Local Failure 3

   4. Protection Against Ratcheting and Progressive Distortion 3

   5. Pure Shear 3

   6. Serviceability Criteria 4

5. Elastic Analysis 4

   1. Stress Limits 4

   2. Combined Stresses 5

   3. Stress Categories 5

   4. Stress Linearization 6

6. Special Stress Considerations 6

   1. Bearing Stress 6

   2. Pure Shear 7

   3. Progressive Distortion of Nonintegral Connections 7

7. Nonlinear Analysis 7

   1. General 7

   2. Limit Analysis 8

   3. Plastic Analysis 8

   4. Shakedown Analysis 8

8. Reporting Results 8

Annex A (informative) Stress Categories for Elastic Analysis 9

Bibliography 11

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