Pipeline Research Council International

Transcription

1 Catalog No. L52047 Pipeline Research Council International PIPELINE REPAIR MANUAL Contract PR Prepared for the Pipeline Research Council International, Inc. Prepared by the following Research Agencies: DNVlCC Technologies, Inc. Edison Welding Institute Authors: Carl E. Jaske, Brian 0. Hart William A. Bruce Publication Date: August 8,2006

2 EXECUTIVE SUMMARY This Pipeline Repair Manual is an updated version of the PRCl Pipeline Repair Manual, PR (AGA L51716), which was published The updated manual discusses response to anomaly or defect discovery, reviews repair methods, identifies appropriate repairs for various types of defects, and provides generic guidelines for use of various repair methods. CC Technologies has reviewed existing and emerging pipeline repair technologies and evaluated them in comparison with those in the current repair manual. The review was based on published literature, vendor literature, and a survey of industry experience. A large number of documents were obtained from the published literature and vendors, but only six pipeline operators responded to the survey of industry experience. Four operators provided written responses, while two provided verbal response to our interview. The revised Pipeline Repair Manual contains added and updated information on repair technologies gleaned from the literature, vendor publications, and survey of industry experience. The section on weld deposition repair and Appendix A on welding on an in-service pipeline has been revised based on the results of extensive research conducted by the Edison Welding Institute. No response was received to our inquiry regarding potential use of information from repair guidelines developed by Europeans, so the section on European repair methods contains minimal revisions. The generic repair procedure has been updated and is included in a separate file for easy use by pipeline operators. In addition to the printed copy of the manual, an Adobe Acrobat (PDF) version has been produced. It can be searched for rapid location of information on a specific topic. This manual does not identify or prescribe all repair methods for all defects or anomalies. Instead, the manual concentrates on commonly encountered defects and commonly used methodologies. Other repair techniques may be equally valid depending on the specific conditions encountered. This revised manual does not provide guidance on current regulations or on code interpretation. National and international codes and regulations change rapidly, and code interpretation is best left to individual companies. Footnotes identify specific sections of selected U. S. regulations.

3 CONTENTS... I. 0. INTRODUCTION RESPONSE TO DISCOVERY OF AN ANOMALY OR DEFECT Key Definitions Pressure Reduction Responses to Leak Surveys Responses to In-Line Inspection Results Responses to Hydrostatic Pressure Test Failures Other Pressure Reduction Considerations Excavation Safety Critical Information for Repair Decisions Pipe Material Pipeline Operating Characteristics Pipeline Configuration Pipeline Location Nature and Extent of Anomaly Available Repair Materials and Personnel Inherent Risk in Performing Repair PIPELINE REPAIR METHODS Removal and Replacement of a Defective Segment Isolation by Freeze Plug Hot Tie-In or Hot Repair Grinding Full-Encirclement Steel Sleeves Type A Sleeves (Reinforcing) Assuring Effective Reinforcement Pressure Reduction Mechanical Loading Hardenable Fillers Fit-Up on Submerged-Arc-Welded and Flash-Welded Line Pipe Epoxy-Filled Shells Steel Compression Sleeves Type B Sleeves: Pressure Containing or Capable of Containing Pressure Design The Importance of Quality Fabrication Sleeve Length Leaking Defects Nonleaking Defects Inspection Requirements Special Sleeve Configurations Sleeves to Repair Girth Welds... 30

4 Sleeves to Repair Couplings Sleeve-On-Sleeve Repair Sleeve Configurations for Curved (Field-Bent) Pipe Defect Repair Using Composite Reinforcement Sleeves Design of Repair Using Composite Reinforcements Requirements for Using Composite Sleeves Weld Deposition Repair Background Burnthrough Hydrogen Cracking Deposition of Repairs Static Strength and Resistance to Pressure Cycles External Repair for Internal Wall Loss Detailed Guidelines for Weld Deposition Repair Industry Experience and Regulatory Activities Limitations on the Use of Weld Deposition Repair Mechanical Clamps Bolt-On Clamps Leak Clamps Hot Tapping Patches and Half Soles APPROPRIATE REPAIRS FOR VARIOUS TYPES OF DEFECTS Overview of Repair Applications Detailed Selection Criteria External Corrosion Internal Corrosion Plain Dents or Dents with Stress Concentrators Longitudinal Cracks and Arc Burns Girth-Weld Defects Wrinkle BendsIBuckles Hard Spots Blisters and Hydrogen-Induced Cracking Couplings Defective Prior Repairs REPAIR METHODS IN EUROPE GUIDELINES FOR A REPAIR PROCEDURE REFERENCES... 78

5 APPENDICES APPENDIX A - Welding On a Live Pipeline APPENDIX B - Survey of Pipeline Operators APPENDIX C - Guidelines for a Repair Procedure vii

6 TABLES Table 1. Table 2. Summary of repair options for various types of defects Summary of qualifying factors for various repair options viii

7 FIGURES Figure 1. Figure 2. Figure 3. Figure 4. Figure 5. Figure 6. Figure 7. Figure 8. Figure 9. Figure 10. Figure I. Figure 12. Figure 13. Figure 14. Figure 15. Figure 16. Illustration of Type A (reinforcing) sleeve Weld details for Type A sleeve Theoretical relationships between carrier pipe stress. repair pressure. and wall thickness Predicted relationships between carrier pipe stress. repair pressure. and degree of fit-up (transfer coefficient) Mechanical methods for assuring tight-fitting Type A sleeves Installation steps for the steel compression sleeve: (A) place half-sleeves on carrier pipe. (B) heat sleeve to expand sleeve. and (C) place field welds and cool assembly to achieve compression (drawing Courtesy of Petro.Line. Inc.) Example of installed and sandblasted steel compression sleeve (photograph Courtesy of Petro.Line. Inc.) Installation of a Type B repair sleeve Illustration of a Type B sleeve Typical sleeve configuration for repair of girth welds (drawing courtesy of Allan Edwards Companies) Typical sleeve configuration for repair of couplings (drawing courtesy of Allan Edwards Companies) Sleeve-on-sleeve repair Armadillo sleeve repair Illustration of the Clock spring' repair system (courtesy of Clock Spring Company. L.P.) Components of the Clock springb repair system: (1) composite wrap. (2) polymer adhesive. and (3) filler compound (courtesy of Clock Spring Company. L.P.) Completed Armor PlateTM repair at a branch connection (courtesy of Armor Plate. Inc.)

8 FIGURES (continued) Figure 17. Figure 18. Figure 19. Figure 20. Figure 21. Figure 22. Figure 23. Figure 24. Figure 25. Figure 26. Figure 27. Figure 28. Figure 29. Figure 30. Figure 31. Figure 32. Figure 33. Figure 34. Completed PermaWrapTM repair at a pipe bend (courtesy of WrapMaster. Inc.) Illustration of typical weld deposition sequence Deposition of perimeter pass and several first layer passes. Initial attention was given to filling deeper areas in this example. simplifying filling of the remaining area Grinding applied to perimeter pass and first layer. Separation between weld toe and ground surface should be about 1-2 mm (1116 inch) Deposition of second perimeter pass and several second layer passes. Separation of the first and second perimeter pass weld toes should be approximately 1-2 mm (1116 inch) Completed repair. In this example. a portion of the wall loss was to be left umrepaired Illustration of weld deposition sequence adapted to external repair of internal wall loss Typical mechanical bolt-on clamp (courtesy of T. D. Williamson. Inc.) Typical leak clamp (courtesy of T. D. Williamson. Inc.) Repairs for external corrosion Repairs for internal corrosion Repairs for plain dents or dents with stress concentrators Repairs for longitudinal cracks and arc burns Repairs for girth-weld defects Repairs for wrinkle bendslbuckles Repairs for hard spots Repairs for blisters and HIC Repairs for couplings... 70

9 FIGURES (continued) Figure 35. Repairs for defective prior repairs Figure 36. Acceptance criterion for circumferential extent of metal-loss defect... 72

10 L PR PRCI Pipeline Repair Manual INTRODUCTION This manual is an updated version of the one produced in 1994.(') As with the original version, the manual provides guidance to pipeline operators for: Choosing an appropriate repair technique for a specific type of defect or combination of defects in an operating pipeline. Developing or improving their pipeline repair procedures and repair manuals. Training or qualifying engineering and maintenance personnel. This manual outlines and describes known and commonly accepted techniques for pipeline repairs, with major emphasis on methods that can be applied to in-service pipelines. The various repair methods and types of defects are summarized in a spreadsheet table where the applicability of each type of repair to a given type of defect is indicated. Defect assessment methods and safety considerations for making pipeline repairs are presented and reviewed. Following the format of the earlier version,(') the updated manual is divided into the following six sections and three appendices: Response to Discovery of an Anomaly or Defect. This section discusses how a pipeline operator should respond following the discovery of an anomaly or defect, including safety issues that should be addressed and information that is required to make an appropriate repair response. Pipeline Repair Methods. This section presents and describes the known and commonly accepted methods for repairing in-service pipelines. Appropriate Repairs for Various Types of Defects. This section points out and describes the types of in-service pipeline repair methods that are applicable to various types of defects found in operating pipelines. Repair Methods in Europe. This section reviews pipeline repair methods used in Europe. Information in the original version of the manual was obtained from the Groupe Europeen de Recherches Gazieres (GERG), whereas recent information was obtained from the European Pipeline Research Group (EPRG). Guidelines for a Repair Procedure. This section introduces a model procedure that can be used by a pipeline operator to create its own new repair procedure, enhance or update its existing procedure, or evaluate its existing repair procedure. In addition to the written version included in this manual (Appendix C), an electronic version is provided with this manual. The electronic version facilitates use of the generic repair procedures by pipeline operators. References. manual. This section lists the references that are cited throughout the

11 L PR PRCl Pipeline Repair Manual Appendix A. This appendix discusses the issues related to welding on an inservice pipeline. It includes information from the research that Edison Welding Institute has performed for PRCI.(*) Appendix 8. This appendix summarizes various repair methods being used by pipeline operators based on a survey of PRCl member companies, other select operators, and providers of repair equipment and services. The authors and CC Technologies thank those who participated in the survey for taking time to respond to our queries and sharing information with us. Appendix C. This appendix contains the written version of a model pipeline repair procedure that can be used by a pipeline operator. This manual does not identify or prescribe all repair methods for all defects or anomalies - no repair manual can serve this purpose. This manual concentrates on commonly encountered defects and commonly used methodologies. Other repair techniques may be equally valid depending on the specific conditions encountered. This manual does not give requirements for evaluations or repair. It uses the word "should" to describe the actions commonly taken when evaluating or repairing an anomaly. Individual companies may choose to require some actions, making others advisory or replacing them with other actions. Finally, this manual does not provide guidance on specific regulations or on code interpretation. National and international codes and regulations change rapidly, and code interpretation is best left to individual companies. On occasion, the manual may identify or comment on items commonly found in regulations, provided those items influence an analysis or repair. Also, footnotes identify specific sections of selected U. S. regulations.