RECOMMENDED PRACTICE DNVGL-RP-D101 Edition July 2017 Structural analysis of piping systems The electronic pdf version of this document, available free of charge from http://www.dnvgl.com, is the officially binding version. DNV GL AS FOREWORD DNV GL recommended practices contain sound engineering practice and guidance. © DNV GL AS July 2017 Any comments may be sent by e-mail to [email protected] This service document has been prepared based on available knowledge, technology and/or information at the time of issuance of this document. The use of this document by others than DNV GL is at the user's sole risk. DNV GL does not accept any liability or responsibility for loss or damages resulting from any use of this document. CHANGES – CURRENT General This document supersedes the October 2008 edition of DNV-RP-D101. The purpose of the revision of this service document is to comply with the new DNV GL document reference code system and profile requirements following the merger between DNV and GL in 2013. Changes mainly consist of updated company name and references to other documents within the DNV GL portfolio. Some references in this service document may refer to documents in the DNV GL portfolio not yet published (planned published within 2017). In such cases please see the relevant legacy DNV or GL document. References to external documents (non-DNV GL) have not been updated. Changes - current Changes • Sec.3 Topside processing piping — [3.11.2.1]: The approach for estimating the blast drag pressure has been changed. Reference to DNVGL-OS-A101 Table-1 and DNVGL-OS-A101 Figure-1 have been added. • Appendix J — Appendix J has been removed. Editorial corrections In addition to the above stated changes, editorial corrections may have been made. Recommended practice — DNVGL-RP-D101. Edition July 2017 Page 3 Structural analysis of piping systems DNV GL AS CONTENTS Changes – current.................................................................................................. 3 Section 1 General.................................................................................................... 7 Contents 1.1 Introduction......................................................................................7 1.2 Objective...........................................................................................7 1.3 Relationship to other codes.............................................................. 7 1.4 References........................................................................................ 7 1.5 Definitions.......................................................................................10 1.6 Abbreviations and symbols............................................................. 11 Section 2 Structural Analysis of Piping Systems................................................... 14 2.1 Introduction....................................................................................14 2.2 Pipe stress and flexibility analysis..................................................14 2.3 Analysis tools..................................................................................17 2.4 Piping design codes........................................................................ 18 Section 3 Topside process piping..........................................................................21 3.1 General........................................................................................... 21 3.2 Commonly used design codes......................................................... 21 3.3 Type of calculations........................................................................21 3.4 Loads to be considered in piping design.........................................21 3.5 Wall thickness calculations............................................................. 23 3.6 Flexibility calculations.................................................................... 24 3.7 Equipment nozzle load calculations................................................ 24 3.8 Flange calculations......................................................................... 26 3.9 Pressure relief- and discharge force calculations............................27 3.10 Expansion and slip-joint thrust load calculations.......................... 28 3.11 Blast load calculations.................................................................. 29 3.12 Fatigue calculations...................................................................... 32 3.13 Non-standard component calculations.......................................... 34 3.14 Load case description- and combinations..................................... 34 3.15 Pipe stress priority piping............................................................ 34 3.16 Design of pipe supports................................................................36 3.17 Documentation of stress analysis................................................. 38 3.18 Verification....................................................................................40 Section 4 Subsea piping........................................................................................41 4.1 General........................................................................................... 41 Recommended practice — DNVGL-RP-D101. Edition July 2017 Page 4 Structural analysis of piping systems DNV GL AS 4.2 Commonly used design codes......................................................... 41 4.3 DNVGL-ST-F101 Submarine pipeline systems................................. 42 4.4 Recommended design cases........................................................... 42 4.5 Hydrogen induced stress cracking (HISC)...................................... 43 4.6 Documentation of pipe stress analysis........................................... 44 4.7 Verification..................................................................................... 44 Contents Section 5 Non standard piping components..........................................................45 5.1 General........................................................................................... 45 5.2 Requirements in piping codes.........................................................45 5.3 FEA design and qualification of non-standard piping components.......................................................................................... 46 Section 6 Verification............................................................................................ 51 6.1 General........................................................................................... 51 6.2 Self check....................................................................................... 51 6.3 Internal verification........................................................................51 6.4 Verification carried out by a 3rd part............................................. 51 Appendix A Vortex induced vibrations.................................................................. 54 A.1 General........................................................................................... 54 A.2 Relevance to piping...................................................................... 54 A.3 Scope.............................................................................................. 54 A.4 Important parameters.................................................................... 54 A.5 Vortex shedding frequency.............................................................55 A.6 Lock-in............................................................................................56 A.7 In-line VIV......................................................................................56 A.8 Cross-flow VIV................................................................................56 A.9 Reduced velocity, VR...................................................................... 56 A.10 Stability parameter, Ks................................................................. 56 A.11 Effective mass, me....................................................................... 57 A.12 Added mass, ma........................................................................... 57 A.13 Limitation to added-mass equation.............................................. 57 A.14 Common error in pipe stress software......................................... 58 A.15 Wind induced vortex shedding..................................................... 58 A.16 Sea current induced vortex shedding........................................... 58 A.17 Recommended VIV check-out procedure...................................... 59 A.18 Methods used to reduce VIV........................................................ 60 A.19 Physical properties of air and seawater........................................61 Recommended practice — DNVGL-RP-D101. Edition July 2017 Page 5 Structural analysis of piping systems DNV GL AS Appendix B Analyst check list, global analysis......................................................62 Appendix C Third party check list, global Analysis................................................64 Appendix D Check list, local FE-analysis............................................................... 66 Contents Appendix E Restraint symbols...............................................................................68 Appendix F Pipe stress isometric.......................................................................... 69 Appendix G Load case combinations..................................................................... 70 Appendix H Subsea load