- piping.pdf

PIPING HANDBOOK

Mohinder L. Nayyar, P.E.ASME Fellow

The sixth edition of this Handbook was edited by

Mohindar L. Nayyar, P.E.

The fifth edition of this Handbook was edited by

Reno C. King, B.M.E, M.M.E., D.Sc., P.E.Professor of Mechanical Engineering and Assistant Dean,School of Engineering and Science, New York University

Registered Professional Engineer

The first four editions of this Handbook were edited by

Sabin Crocker, M.E.Fellow, ASME: Registered Professional Engineer

Seventh Edition

MCGRAW-HILLNew York San Francisco Washington, D.C. Auckland Bogota

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Library of Congress Cataloging-in-Publication Data

Nayyar, Mohinder L.Piping handbook / [edited by] Mohinder L. Nayyar.7th ed.

p. cm.ISBN 0-07-047106-11. PipeHandbooks, manuals, etc. 2. Pipe-fittingHandbooks,manuals, etc. I. Nayyar, Mohinder L.

McGraw-Hill

Copyright 2000, 1992, 1967 by The McGraw-Hill Companies, Inc. Allrights reserved. Printed in the United States of America. Except aspermitted under the United States Copyright Act of 1976, no part of thispublication may be reproduced or distributed in any form or by anymeans, or stored in a data base or retrieval system, without the priorwritten permission of the publisher.

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CONTENTS

Honors List xiPreface xviiHow to Use This Handbook xix

Part A: Piping Fundamentals

Chapter A1. Introduction to Piping Mohinder L. Nayyar A.1

Chapter A2. Piping Components Ervin L. Geiger A.53

Chapter A3. Piping Materials James M. Tanzosh A.125

Chapter A4. Piping Codes and Standards Mohinder L. Nayyar A.179

Chapter A5. Manufacturing of Metallic Piping Daniel R. Avery andAlfred Lohmeier A.243

Chapter A6. Fabrication and Installation of Piping Edward F. Gerwin A.261

Chapter A7. Bolted Joints Gordon Britton A.331

Chapter A8. Prestressed Concrete Cylinder Pipe and FittingsRichard E. Deremiah A.397

Chapter A9. Grooved and Pressfit Piping SystemsLouis E. Hayden, Jr. A.417

v

vi CONTENTS

Chapter A10. Selection and Application of Valves Mohinder L. Nayyar,Dr. Hans D. Baumann A.459

Part B: Generic Design Considerations

Chapter B1. Hierarchy of Design Documents Sabin Crocker, Jr. B.1

Chapter B2. Design Bases Joseph H. Casiglia B.19

Chapter B3. Piping Layout Lawrence D. Lynch,Charles A. Bullinger, Alton B. Cleveland, Jr. B.75

Chapter B4. Stress Analysis of Piping Dr. Chakrapani Basavaraju,Dr. William Saifung Sun B.107

Chapter B5. Piping Supports Lorenzo Di Giacomo, Jr.,Jon R. Stinson B.215

Chapter B6. Heat Tracing of Piping Chet Sandberg,Joseph T. Lonsdale, J. Erickson B.241

Chapter B7. Thermal Insulation of Piping Kenneth R. Collier,Kathleen Posteraro B.287

Chapter B8. Flow of Fluids Dr. Tadeusz J. Swierzawski B.351

Chapter B9. Cement-Mortar and Concrete Linings for PipingRichard E. Deremiah B.469

Chapter B10. Fusion Bonded Epoxy Internal Linings and ExternalCoatings for Pipeline Corrosion Protection Alan Kehr B.481

Chapter B11. Rubber Lined Piping Systems Richard K. Lewis,David Jentzsch B.507

CONTENTS vii

Chapter B12. Plastic Lined Piping for Corrosion ResistanceMichael B. Ferg, John M. Kalnins B.533

Chapter B13. Double Containment Piping SystemsChristopher G. Ziu B.569

Chapter B14. Pressure and Leak Testing of Piping SystemsRobert B. Adams, Thomas J. Bowling B.651

Part C: Piping Systems

Chapter C1. Water Systems Piping Michael G. Gagliardi,Louis J. Liberatore C.1

Chapter C2. Fire Protection Piping Systems Russell P. Fleming,Daniel L. Arnold C.53

Chapter C3. Steam Systems Piping Daniel A. Van Duyne C.83

Chapter C4. Building Services Piping Mohammed N. Vohra,Paul A. Bourquin C.135

Chapter C5. Oil Systems Piping Charles L. Arnold, Lucy A. Gebhart C.181

Chapter C6. Gas Systems Piping Peter H. O. Fischer C.249

Chapter C7. Process Systems Piping Rod T. Mueller C.305

Chapter C8. Cryogenic Systems Piping Dr. N. P. Theophilos,Norman H. White, Theodore F. Fisher, Robert Zawierucha,M. J. Lockett, J. K. Howell, A. R. Belair, R. C. Cipolla,Raymond Dale Woodward C.391

Chapter C9. Refrigeration Systems Piping William V. Richards C.457

viii CONTENTS

Chapter C10. Hazardous Piping Systems Ronald W. Haupt C.533

Chapter C11. Slurry and Sludge Systems Piping Ramesh L. Gandhi C.567

Chapter C12. Wastewater and Stormwater Systems PipingDr. Ashok L. Lagvankar, John P. Velon C.619

Chapter C13. Plumbing Piping Systems Michael Frankel C.667

Chapter C14. Ash Handling Piping Systems Vincent C. Ionita,Joel H. Aschenbrand C.727

Chapter C15. Compressed Air Piping Systems Michael Frankel C.755

Chapter C16. Compressed Gases and Vacuum Piping SystemsMichael Frankel C.801

Chapter C17. Fuel Gas Distribution Piping Systems Michael Frankel C.839

Part D: Nonmetallic Piping

Chapter D1. Thermoplastics Piping Dr. Timothy J. McGrath,Stanley A. Mruk D.1

Chapter D2. Fiberglass Piping Systems Carl E. Martin D.79

Part E: Appendices

Appendix E1. Conversion Tables Ervin L. Geiger E.1

Appendix E2. Pipe Properties (US Customary Units)Dr. Chakrapani Basavaraju E.13

CONTENTS ix

Appendix E2M. Pipe Properties (Metric) Dr. Chakrapani Basavaraju E.23

Appendix E3. Tube Properties (US Customary Units) Ervin L. Geiger E.31

Appendix E3M. Tube Properties (Metric) Troy J. Skillen E.37

Appendix E4. Friction Loss for Water in Feet per 100 Feet of Pipe E.39

Appendix E4M. Friction Loss for Water in Meters per 100 Meters ofPipe Troy J. Skillen E.59

Appendix E5. Acceptable Pipe, Tube and Fitting Materials perthe ASME Boiler and Pressure Vessel Code and the ASME PressurePiping Code Jill M. Hershey E.61

Appendix E6. International Piping Material SpecificationsR. Peter Deubler E.69

Appendix E7. Miscellaneous Fluids and Their Properties Akhil Prakash E.83

Appendix E8. Miscellaneous Materials and Their PropertiesAkhil Prakash E.101

Appendix E9. Piping Related Computer Programs and TheirCapabilities Anthony W. Paulins E.109

Appendix E10. International Standards and Specifications for Pipe, Tube,Fittings, Flanges, Bolts, Nuts, Gaskets and Valves Soami D. Suri E.119

Index I.1

HONORS LIST

CONTRIBUTORS

Robert B. Adams, President & CEO, Expansion Seal Technologies, 334 Godshall Drive,Harleysville, PA 19438-2008 (CHAP. B14)

Charles L. Arnold, Principal Pipeline Consultant, 716 Hillside Avenue, Albany, CA 94706(CHAP. C5)

Joel E. Aschenbrand, James S. Merritt Company, Lizell Building, Suite 202, P. O. Box 707,Montgomeryville, PA 18936-0707 (CHAP. C14)

Daniel R. Avery, Technical Marketing Manager, Wyman-Gordon Forgings, Inc., CameronForged Product Division, P. O. Box 40456, Houston, TX 77240-0456 (CHAP. A5)

Dr. Chakrapani Basavaraju, Engineering Specialist, Bechtel Corporation, 5275 WestviewDrive, Frederick, MD 21703 (CHAP. B4 AND APPS. E2 AND E2M)

Dr. Hans D. Baumann, Fisher Controls International, Inc., Portsmouth, NH 03801 (CHAP. A10)

A. R. Belair, PRAXAIR, Inc., 175 East Park Drive, P.O. Box 44, Tonawanda, NY 14150-2053 (CHAP. C8)

Paul A. Bourquin, Formerly Senior Vice President, Wolff & Munier, Inc., 50 Broadway,Hawthorne, NY 10532 (CHAP. C4)

Thomas J. Bowling, P.E., Manager, Pipe Repair Product Line, Team Environmental Ser-vices, Inc., Alvin, TX 77512 (CHAP. B14)

Gordon Britton, President, Integra Technologies Limited, 1355 Confederation Street, Sarnia,Ontario, N7T7J4, Canada (CHAP. A7)

Charles A. Bullinger, Formerly Engineering Specialist, Bechtel Corporation, 5275 WestviewDrive, Frederick, MD 21703 (CHAP. B3)

Joseph H. Casiglia, P.E. Consulting Engineer, Piping, Detroit Edison, 2000 Second Ave.,Detroit, MI 48226 (CHAP. B2)

R. C. Cipolla, Cryogenic Equipment Engineer, PRAXAIR, Inc., 175 East Park Drive, P.O.Box 44, Tonawanda, NY 14150-2053 (CHAP. C8)

Alton B. Cleveland, Jr., President, Jacobus Technology, Inc., 7901 Beech Craft Ave., Gaith-ersburg, MD 20879 (CHAP. B3)

Kenneth R. Collier, Systems Engineer, Pittsburgh Corning, 800 Presque Isle Drive, Pitts-burgh, PA 15239 (CHAP. B7)

Sabin Crocker, Jr., P.E. 307 Claggett Drive, Rockville, MD 20851 (CHAP. B1)

Richard E. Deremiah, P.E., Project Manager, Price Brothers Company, 367 West SecondAvenue, Dayton, OH 45402 (CHAPS. A8 AND B9)

R. Peter Deubler, P.E., Technical Director, Fronek Company, Inc., 15 Engle Street, Engle-wood, NJ 07631 (APP. E6)

Lorenzo DiGiacomo, Jr., Senior Engineer, Bechtel Power Corporation, 5275 Westview Drive,Frederick, MD 21703 (CHAP. B5)

C. J. Erickson, Engineering Consultant, Retired from E. I. DuPont De Nemours & Co.,P.O. Box 6090, Newark, DE 19714-6090 (CHAP. B6)

xi

xii HONORS LIST

Michael B. Ferg, Marketing Engineer, Crane Resistoflex Company, One Quality Way, Mar-ion, NC 28752 (CHAP. B12)

Peter H. O. Fischer, Manager, Pipeline Operations, Bechtel Corporation, P.O. Box 193965,50 Beale Street, San Francisco, CA 94119 (CHAP. C6)

Theodore F. Fisher, Process Engineer, PRAXAIR, Inc., 175 East Park Drive, P.O. Box 44,Tonawanda, NY 14150-2053 (CHAP. C8)

Russell P. Fleming, P.E., Vice President Engineering, National Fire Sprinkler Association,Inc., Robin Hill Corporate Park, Route 22, P. O. Box 1000, Patterson, NY 12563 (CHAP. C2)

Phillip D. Flenner, P.E., Staff Engineer Welding, Consumer Energy, Palisades Nuclear Plant,27780 Blue Star Highway, Covert, MI 49043-9530 (CHAP. C10)

Michael Frankel, CIPE, 56 Emerson Road, Somerset, NJ 08873 (CHAPS. C13, C15, C16 AND C17)

Michael G. Gagliardi, Manager, Raytheon Engineers & Constructors, 160 Chubb Avenue,Lyndhurst, NJ 07071 (CHAPS. C1 AND APP. E4)

Dr. William E. Gale, P.E., Bundy, Gale & Shields, 44 School Terrace, Novato, CA 94945(CHAP. C10)

Ramesh L. Gandhi, Chief Slurry Engineer, Bechtel Corporation, P.O. Box 193965, 50 BealeStreet, San Francisco, CA 94119 (CHAP. C11)

Lucy A. Gebhart, Pipeline Engineer, Bechtel Corporation, P.O. Box 193965, 50 Beale Street,San Francisco, CA 94119 (CHAP. C5)

Ervin L. Geiger, P.E., Engineering Supervisor, Bechtel Corporation, 5275 Westview Drive,Frederick, MD 21703 (CHAP. A2, APPS. E1 AND E3)

Edward F. Gerwin, Life Fellow ASME, 1515 Grampian Boulevard, Williamsport, PA 17701(CHAP. A6)

Ronald W. Haupt, P.E., Senior Consultant, Pressure Piping Engineering Assoc., 291 PuffinCourt, Foster City, CA 94404-1318 (CHAP. C10)

Louis E. Hayden, Jr., Divisional Operations Manager, Victaulic Company of America, 4901Kesslersville Road, Easton, PA 18040 (CHAP. A9)

Jill M. Hershey, Mechanical Engineer, Bechtel Power Corporation, 5275 Westview Drive,Frederick, MD 21703 (APP. E5)

J. K. Howell, Cold Box Engineer, PRAXAIR, Inc., 175 East Park Drive, P.O. Box 44,Tonawanda, NY 14150-2053 (CHAP. C8)

Vincent C. Ionita, Senior Engineering Specialist, 5275 Westview Drive, Frederick, MD 21703(CHAP. C14)

David Jentzsch, General Manager, Blair Rubber Company, 1252 Mina Avenue, Akron, OH44321 (CHAP. B11)

John M. Kalnins, Crane Resistoflex Company, 4675 E. Wilder Road, Bay City, MI 48706(CHAP. B12)

J. Alan Kehr, Technical Marketing Manager, 3M Company, 3M Austin Center, BuildingA147-4N-02, 6801 River Place Boulevard, Austin, TX 78726-9000 (CHAP. B10)

Dr. Ashok L. Lagvankar, Vice President, Earth Tech., 3121 Butterfield Road, Oak Brook,IL 60523 (CHAP. C12)

Richard K. Lewis, Executive Vice President, Blair Rubber Company, 1252 Mina Avenue,Akron, OH 44321 (CHAP. B11)

Louis J. Liberatore, Staff Engineer, Raytheon Engineers & Constructors, 160 Chubb Avenue,Lyndhurst, NJ 07071 (CHAP. C1 AND APP. E4)

HONORS LIST xiii

Alfred Lohmeier, Materials Engineer, Formerly Vice President, Stanitomo Corporation ofAmerica, 345 Park Ave., New York, NY 10154 (CHAP. A5)

Michael J. Lockett, PRAXAIR, Inc., 175 East Park Drive, P.O. Box 44, Tonawanda, NY14150-2053 (CHAP. C8)

Joseph T. Lonsdale, Director of Engineering, Dryden Engineering Company, Fremont, CA94063 (CHAP. B6)

Lawrence D. Lynch, Engineering Supervisor, Bechtel Power Corporation, 5275 WestviewDrive, Frederick, MD 21703 (CHAP. B3)

Carl E. Martin, Director Marketing, Fibercast Company, P.O. Box 968, Sand Springs, Okla-homa 74063-0968 (CHAP. D2)

Timothy J. McGrath, Principal, Simpson, Gumpertz & Heger, Inc., 297 Broadway, Arling-ton, MA 02174-5310 (CHAP. D1)

Stanley A. Mruk, 115 Grant Avenue, New Providence, NJ 07974 (CHAP. D1)

Rod T. Mueller, Engineering Standards Coordinator, Exxon Research & Engineering Co.,180 Park Avenue, Florham Park, NJ 07932 (CHAP. C7)

Mohinder L. Nayyar, P.E., ASME Fellow, Bechtel Power Corporation, 5275 Westview Drive,Frederick, MD 21703 (CHAPS. A1, A4, AND A10)

Alan D. Nance, A. D. Nance Associates, Inc., 4545 Glenda Lane, Evans, GA 30809-3215(CHAP. C10)

Kathleen Posteraro, Systems Engineer, Pittsburgh Corning, 800 Presque Isle Drive, Pitts-burgh, PA 15239 (CHAP. B7)

Anthony Paulin, President, Anthony Research Group, 25211 Gregans Mill Road, Suite 315,Spring, TX 77380-2924 (APP. E9)

Akhil Prakash, P.E., Supervisor Engineer, 12741 King Street, Overland Park, KS 66213 (APPS.E7 AND E8)

William V. Richards, P.E., 4 Court of Fox River Valley, Lincolnshire, IL 60069 (CHAP. C9)

Chet Sandberg, Chief Engineer, Raychem Corporation, 300 Constitution Drive, Menlo Park,CA 94025-1164 (CHAP. B6)

Robert E. Serb, P.E., Pressure Piping Engineering Assoc., 291 Puffin Court, Foster City,CA 94404-1318 (CHAP. C10)

Troy J. Skillen, Mechanical Engineer, Bechtel Power Corporation, 5275 Westview Drive,Frederick, MD 21703 (APPS. E3M AND E4M)

Soami D. Suri, P.E., Senior Mechanical Engineer, Bechtel Power Corporation, 5275 WestviewDrive, Frederick, MD 21703 (APP. E10)

Jon R. Stinson, Supervisor, Engineering, Lisega, Inc., 375 West Main Street, Newport, TN37821 (CHAP. B5)

Dr. William Saifung Sun, Engineering Specialist, Bechtel Power Corporation, 5275 WestviewDrive, Frederick, MD 21703 (CHAP. B4)

Dr. Tadeusz J. Swierzawski, 50 Chandler Road, Burlington, MA 01803 (CHAP. B8)

James M. Tanzosh, Supervisor, Materials Engineering, Babcock & Wilcox Co., 20 S. VanBuren Ave., Barberton, OH 44203 (CHAP. A3)

N. P. Theophilos, Standards Manager, PRAXAIR, Inc., 175 East Park Drive, P.O. Box 44,Tonawanda, NY 14150-2053 (CHAP. C8)

Daniel A. Van Duyne, 206 Nautilus Drive, Apt. No. 107, New London, CT 06320 (CHAP. C3)

xiv HONORS LIST

John P. Velon, Vice President, Harza Engineering Company, Sears Towers, 233 SouthWacker Drive, Chicago, IL 60606-6392 (CHAP. C11)

Mohammed N. Vohra, Consulting Engineer, 9314 Northgate Road, Laurel, MD 20723(CHAP. C4)

Norman H. White, Applications Engineer, PRAXAIR, Inc., 175 East Park Drive, P.O. Box44, Tonawanda, NY 14150-2053 (CHAP. C8)

Raymond Dale Woodward, PRAXAIR, Inc., 175 East Park Drive, P.O. Box 44, Tona-wanda, NY 14150-2053 (CHAP. C8)

Robert Zawierucba, Materials Engineer, PRAXAIR, Inc., 175 East Park Drive, P.O. Box44, Tonawanda, NY 14150-2053 (CHAP. C8)

Christopher G. Ziu, 7 Douglas Street, Merrimack, NH 03054 (CHAP. B13)

REVIEWERS

Harry A. Ainsworth, S.P.E., Consultant, 4 Maple Avenue, Sudbury, MA 01776-344

Karen L. Baker, Senior Mechanical Engineer, Bechtel Power Corporation, 5275 WestviewDrive, Frederick, MD 21703

Dr. C. Basavaraju, Senior Engineering Specialist, Bechtel Power Corporation, 5275 WestviewDrive, Frederick, MD 21703

Robert Burdick, Bassett Mechanical, P. O. Box 755, Appleton, WI 54912-0755

Richard E. Chambers, Principal, Simpson, Gumpertz & Hager, Inc., 297 Broadway, Arling-ton, MA 02174

Sabin Crocker, Jr., P.E., 307 Claggett Drive, Rockville, MD 20878. Formerly Project Engi-neer, Bechtel Power Corporation, 5275 Westview Drive, Frederick, MD 21703

Donald R. Frikken, P.E., Engineering Fellow, Solutia, Inc. 10300 Olive Boulevard, St. Louis,MO 63141-7893

E. L. Geiger, P.E. Engineering Supervisor, Bechtel Power Corporation, 5275 Westview Drive,Frederick, MD 21703

James Gilmore, Senior Engineering Specialist, Bechtel Power Corporation, 5275 WestviewDrive, Frederick, MD 21703

Evans C. Goodling, Jr., P.E., Consulting Engineer, Parsons Energy & Chemical Group,2675 Morgantown Road, Reading, PA 19607-9676

John Gruber, Senior Engineering Specialist, Bechtel Power Corporation, 5275 WestviewDrive, Frederick, MD 21703

Charles Henley, Engineering Supervisor, Black & Veach, 8400 Ward Parkway, P. O. Box8405, Kansas City, MO 64114

Jill M. Hershey, Mechanical Engineer, Bechtel Power Corporation, 5275 Westview Drive,Frederick, MD 21703

Michele L. Jocelyn, P.E., Mechanical Engineer, Bechtel Power Corporation, 5275 WestviewDrive, Frederick, MD 21703

H. Steven Kanofsky, P.E., Principal Civil Engineer, Washington Suburban Sanitary Com-mission, 14501 Sweitzer Lane, Laurel, MD 20707 (CHAP. C1)

James Kunze, Vice President, P.E., Earth Tech., 1020 North Broadway, Milwaukee, WI53202

HONORS LIST xv

Donald J. Leininger, 7810 College View Court, Roanoke, VA 24019-4442

Jimmy E. Meyer, Middough Association, Inc., 1910E 13th Street, Suite 300, Cleveland, OH44114-3524

Ronald G. McCutcheon, Senior Design Engineer, Mechanical Systems & Equipment Depart-ment, Ontario Hydro Nuclear, 700 University Avenue, Toronto, ON, Canada, M5G1X6

Mohinder L. Nayyar, ASME Fellow, Bechtel Power Corporation, 5275 Westview Drive,Frederick, MD 21703

Ann F. Paine, P.E., Senior Engineering Specialist, Bechtel Power Corporation, 5275 WestviewDrive, Frederick, MD 21703


Henry R. Sonderegger, P.E., Engineering Manager, Research and Development Center,1467 Elmwood Avenue, Cranston, RI 02910

George W. Spohn, III, Executive Vice President, Coleman Spohn Corporation, 1775 E. 45thStreet, Cleveland, OH 44103-2318

Kristi Vilminot, Engineering Supervisor, Black & Veach, 2200 Commonwealth Boulevard,Ann Arbor, MI 48105

Mahmood Naghash, Senior Engineering Specialist, Bechtel Power Corporation, 5275 West-view Drive, Frederick, MD 21703

Ralph W. Rapp, Jr., Senior Staff Engineer, Shell Oil Product Company, P. O. Box 2099,Houston, TX 77252-2099.

Gursharan Singh, Engineering Supervisor, Bechtel Power Corporation, 5275 WestviewDrive, Frederick, MD 21703

Walter M. Stephan, Engineering Manager, Flexitallic, Inc., 1300 Route 73, Suite 311, Mt.Laurel, NJ 08054

Dr. Jagdish K. Virmani, Senior Engineering Specialist, Bechtel Power Corporation, 5275Westview Drive, Frederick, MD 21703

Charles Webb, Application Engineer, Ameron, P. O. Box 878, Burkburnett, TX 76354

Horace E. Wetzell, Jr., Vice President, The Smith & Oby Company, 6107 Carnegie Avenue,Cleveland, OH 44103

TECHNICAL AND ADMINISTRATIVE SUPPORT

Michelle A. Clay, Project Administrator, Bechtel Power Corporation, 5275 Westview Drive,Frederick, MD 21703

Rohit Goel, Piping Engineer, Bechtel India Limited, 249A Udyog Vihar, Phase IV, Gurgaon-122015, Haryana, India

Jill M. Hershey, Mechanical Engineer, Bechtel Power Corporation, 5275 Westview Drive,Frederick, MD 21703

Dheeraj Modawel, Piping Engineer, Bechtel India Limited, 249A Udyog Vihar, Phase IV,Gurgaon-122015, Haryana, India

Darya Nabavian, Mechanical Engineer, Bechtel Corporation, 5275 Westview Drive, Freder-ick, MD 21703

xvi HONORS LIST

Sandeep Singh, Piping Engineer, Bechtel India Limited, 249A Udyog Vihar, Phase IV,Gurgaon-122015, Haryana, India

Troy J. Skillen, Mechanical Engineer, Bechtel Power Corporation, 5275 Westview Drive,Frederick, MD 21703

M. C. Stapp, Project Administrator, Bechtel Power Corporation, 5275 Westview Drive, Fred-erick, MD 21703


James Kenyon White, Administrative Supervisor, Bechtel Power Corporation, 5275 West-view Drive, Frederick, MD 21703

Dolly Pollen, 656 Quince Orchard Road, Gaithersburg, MD 20878

PREFACE

It is with great sense of gratitude and humility I take this blessed moment to offerthis Seventh Edition of Piping Handbook. The challenge presented by the successof the Sixth Edition, coupled with our objective to enhance its reference value andwiden its scope, motivated us to reach out and draw upon the recognized expertiseon piping related topics not covered in the Sixth Edition. In addition, we directedour synergetic efforts to upgrade the existing contents to include the latest advancesand developments in the field of piping and related technologies.

Fifteen (15) new chapters and nine (9) new appendixes have been added. Theseadditions accord a unique status to this resource book as it covers piping relatedtopics not covered in any one book. Inclusion of metric and/or SI units along withUS customary units is intended to accommodate the growing needs of the shrinkingworld and the realities of the international market. We have maintained the familiarand easy to use format of the Sixth Edition.

I consider myself fortunate to have the opportunity to associate and work withrenowned and recognized specialists and leaders whose contributions are not limitedto this Piping Handbook, but go far beyond. For me it has been a rewarding andenlightening experience. I find myself humbled by depth of their knowledge, practi-cal experience, and professional achievements. These distinguished contributorshave offered the sum total of their know how in the form of guidance, cautions,prohibitions, recommendations, practical illustrations, and examples, which shouldbe used prudently with due consideration for application requirements. Thestrength, authenticity, and utility of this reference book lie in the wide spreaddiversity of their expertise and unity of their professionalism.

Based upon the feedback received over the past seven years from the users ofthe Sixth Edition of this handbook, I feel honored to express my and users gratitudeto all the contributors for their commitment to their profession and their highergoal of helping others. They have made the difference. Their spirit of giving backhas not only continued, but has brought in new contributors to expand the scopeand enhance the utility of this handbook. I feel confident that all the contributorsshall enjoy the professional satisfaction and the gratitude of users of this handbook.

The selfless efforts of all the reviewers listed in the Honors List are of greatsignificance in making improvements in presentation of the subject matter. Theextent of their experience, knowledge, and an insight of topics has been instrumentalin extracting the best out of contributors and upgrading the contents of thishandbook.

The contributors and reviewers have earned a distinguished status. I salute theircommitment; admire their efforts; respect their professionalism; and applaud theirachievements. I want to recognize their perseverance, dedication, hard work andsincerity of their commitment in spite of increasing demands on their time.

I am indebted to the members of the editorial team who spent countless hoursand made personal sacrifices to make this team project a reality. Jill Hershey, TroySkillen, and Soami Suri did not spare any effort to not only fulfill their commitment,but went beyond to accomplish the objectives. They offered constructive comments,

xvii

xviii PREFACE

new ideas and energy to support them. In addition to contributing, they assistedme in reviewing, editing, checking and correcting the manuscript. Furthermore,they provided an objective assessment of needs of progressive professionals involvedin piping related fields. Their efforts reinforced my faith in bright future of ourprofession. The support and assistance provided by Ervin L. Geiger and SabinCrocker, Jr., as Associate Editors, is key to the successful completion of this effort.

Each and every individual providing administrative, technical and automationservices, listed in Honors List, kept the entire process moving smoothly by theirsincere efforts. Linda Ludewig, Peggy Lamb, and the others at McGraw-Hill couldnot be better or more cooperative in accommodating our reasonable and unreason-able requests in producing this handbook to the best of their abilities.

Whenever you, the readers and users of this handbook, find it to be of help inyour mission, please thank the contributors, reviewers, technical, administrativeand automation personnel listed in the Honors List, and the editorial and productionstaff of McGraw-Hill. If, at any time, this handbook falls short of your expectations,please do not hesitate to pass it on to me. It will help us improve the contents andtheir utility. I shall owe you my gratitude.

I take pride in recognizing the active support of my daughters, Mukta andMahak; and my son, Manav; who helped me in researching and collecting data;preparing manuscript; reviewing proof pages; and performing other tasks, as needed.This time they not only allowed me to devote their share of my life to this handbook,but also dedicated a part of their life to it. My wife, Prabha, provided the proverbialsupport a spouse can hope for, in doing and accomplishing what I aimed for. Nowords can convey my feelings and thoughts for her contributions.

Mohinder L. Nayyar

HOW TO USE THISHANDBOOK

As with any handbook, the user of this handbook can seek the topic covered eitherwith the help of the table of contents or the index. However, an understanding ofthe organization and the format of this handbook will enhance its utility.The handbook is organized in five parts:

Part A, Piping Fundamentals: There are ten chapters in Part A, numberedAl through A10, dealing with commonly used terminology associated with pipingunitsU.S. Customary units and metric/SI units, piping components, materials,piping codes and standards, manufacturing of piping, fabrication and installationof piping, bolted joints, prestressed concrete piping, and grooved and Pressfit pipingsystems, Each chapter is a self-contained unit. The chapter numbers, figures andtables sequentially preceded. For example, in the case of Chapter Al, the figuresare numbered as Fig. A1.1, Fig. A1.2, and so on, and tables are numbered as TableA1.1, Table A1.2, and so on. Pages are numbered sequentially throughout eachpart, starting with A.1.

Part B, Generic Design Considerations: The Part B consists of fourteen chapters.The topics covered deal with generic design considerations, which may be applicableto any piping system irrespective of the fluid or the mixture carried by the piping.The generic topics are design documents, design bases, piping layout, stress analysis,piping supports, heat tracing, thermal insulation, and flow of fluids. In addition, thelined piping systems: cement, rubber, epoxy and plastic lined piping systems areincluded to provide guidance when corrosion is a concern. A chapter on doublecontainment piping systems provides needed guidance to handle hazardous fluids.The last chapter in Part B deals with pressure testing of piping systems. The chapter,page, figure, and table numbering scheme is similar to that described for Part A.

Part C, Piping Systems: There are 17 chapters in Part C, each dealing with aspecific type of piping system or systems involving application of specific considera-tions. The piping systems covered include water, fire protection, steam, buildingservices, oil, gas, chemical and refinery (process piping), cryogenic, refrigeration,toxic and hazardous wastes, slurry and sludge, stormwater and wastewater, plumb-ing, ash handling, compressed air and vacuum, fuel gas and laboratory pipingsystems. The numbering approach for Part C is similar to Part A.

Part D, Nonmetallic Piping: Part D has two chapters, Dl and D2. Chapter Dladdresses thermoplastics piping, and Chapter D2 covers fiberglass piping systems.The numbering scheme for pages, figures, and tables is similar to the one followedfor Part A.

Part E, Appendixes: Part E of the handbook contains reference technical dataand information that could be very handy and useful to the users. It consists of 10appendixes, El through E10. They include conversion tables, pipe and tube proper-ties, pressure drop tables, ASTM and international piping materials, fluid properties,piping related computer programs, and an exhaustive list of international standards.

Depending upon the need, level of piping knowledge, and requirements, the

xix

xx HOW TO USE THIS HANDBOOK

user of this handbook may find it very convenient to locate the desired informationby focusing on a specific part of the handbook.

Last but not least, the Seventh Edition of Piping Handbook includes metric/SIunits in parentheses. The values stated in each system are not exact equivalents;therefore, each system must be used independently of the other. At times, unitequivalents are rounded off while at places they are approximated to provide ameasure of equivalency. Different approaches have been followed depending uponthe practices prevalent in a segment of the piping industry. We regret the variationsand expect the users to understand the state of the art in regard to use of units.The users are cautioned to check and verify units prior to making calculations withthe help of equations included in the handbook or elsewhere.

P A R T A

PIPINGFUNDAMENTALS

CHAPTER A1INTRODUCTION TO PIPING

Mohinder L Nayyar, P. E.ASME Fellow

Bechtel Power Corporation

INTRODUCTION

Piping systems are like arteries and veins. They carry the lifeblood of moderncivilization. In a modern city they transport water from the sources of water supplyto the points of distribution; convey waste from residential and commercial buildingsand other civic facilities to the treatment facility or the point of discharge. Similarly,pipelines carry crude oil from oil wells to tank farms for storage or to refineriesfor processing. The natural gas transportation and distribution lines convey naturalgas from the source and storage tank forms to points of utilization, such as powerplants, industrial facilities, and commercial and residential communities. In chemicalplants, paper mills, food processing plants, and other similar industrial establish-ments, the piping systems are utilized to carry liquids, chemicals, mixtures, gases,vapors, and solids from one location to another.

The fire protection piping networks in residential, commercial, industrial, andother buildings carry fire suppression fluids, such as water, gases, and chemicals toprovide protection of life and property. The piping systems in thermal power plantsconvey high-pressure and high-temperature steam to generate electricity. Otherpiping systems in a power plant transport high- and low-pressure water, chemicals,low-pressure steam, and condensate. Sophisticated piping systems are used to pro-cess and carry hazardous and toxic substances. The storm and wastewater pipingsystems transport large quantities of water away from towns, cities, and industrialand similar establishments to safeguard life, property, and essential facilities.

In health facilities, piping systems are used to transport gases and fluids formedical purposes. The piping systems in laboratories carry gases, chemicals, vapors,and other fluids that are critical for conducting research and development. In short,the piping systems are an essential and integral part of our modern civilization justas arteries and veins are essential to the human body.

The design, construction, operation, and maintenance of various piping systemsinvolve understanding of piping fundamentals, materials, generic and specific designconsiderations, fabrication and installation, examinations, and testing and inspectionrequirements, in addition to the local, state and federal regulations.

A.3

A.4 PIPING FUNDAMENTALS

PIPING

Piping includes pipe, flanges, fittings, bolting, gaskets, valves, and the pressure-containing portions of other piping components. It also includes pipe hangers andsupports and other items necessary to prevent overpressurization and overstressingof the pressure-containing components. It is evident that pipe is one element or apart of piping. Therefore, pipe sections when joined with fittings, valves, and othermechanical equipment and properly supported by hangers and supports, arecalled piping.

Pipe

Pipe is a tube with round cross section conforming to the dimensional require-ments of

ASME B36.10M Welded and Seamless Wrought Steel Pipe ASME B36.19M Stainless Steel Pipe

Pipe Size

Initially a system known as iron pipe size (IPS) was established to designate thepipe size. The size represented the approximate inside diameter of the pipe ininches. An IPS 6 pipe is one whose inside diameter is approximately 6 inches (in).Users started to call the pipe as 2-in, 4-in, 6-in pipe and so on. To begin, each pipesize was produced to have one thickness, which later was termed as standard (STD)or standard weight (STD. WT.). The outside diameter of the pipe was standardized.

As the industrial requirements demanded the handling of higher-pressure fluids,pipes were produced having thicker walls, which came to be known as extra strong(XS) or extra heavy (XH). The higher pressure requirements increased further,requiring thicker wall pipes. Accordingly, pipes were manufactured with doubleextra strong (XXS) or double extra heavy (XXH) walls while the standardizedoutside diameters are unchanged.

With the development of stronger and corrosion-resistant piping materials, theneed for thinner wall pipe resulted in a new method of specifying pipe size andwall thickness. The designation known as nominal pipe size (NPS) replaced IPS,and the term schedule (SCH) was invented to specify the nominal wall thicknessof pipe.

Nominal pipe size (NPS) is a dimensionless designator of pipe size. It indicatesstandard pipe size when followed by the specific size designation number withoutan inch symbol. For example, NPS 2 indicates a pipe whose outside diameter is2.375 in. The NPS 12 and smaller pipe has outside diameter greater than the sizedesignator (say, 2, 4, 6, . . .). However, the outside diameter of NPS 14 and largerpipe is the same as the size designator in inches. For example, NPS 14 pipe has anoutside diameter equal to 14 in. The inside diameter will depend upon the pipewall thickness specified by the schedule number. Refer to ASME B36.10M orASME B36.19M. Refer to App. E2 or E2M.

Diameter nominal (DN) is also a dimensionless designator of pipe size in themetric unit system, developed by the International Standards Organization (ISO).It indicates standard pipe size when followed by the specific size designation number

INTRODUCTION TO PIPING A.5

TABLE A1.1 Pipe Size Designators: NPS and DN

NPS DN NPS DN NPS DN NPS DN

6 3 90 22 550 44 1100 8 4 100 24 600 48 1200 10 5 125 26 650 52 1300 15 6 150 28 700 56 1400 20 8 200 30 750 60 1500

1 25 10 250 32 800 64 16001 32 12 300 34 850 68 17001 40 14 350 36 900 72 18002 50 16 400 38 950 76 19002 65 18 450 40 1000 80 20003 80 20 500 42 1050

Notes:

1. For sizes larger than NPS 80, determine the DN equivalent by multiplying NPS size designation numberby 25.

without a millimeter symbol. For example, DN 50 is the equivalent designation ofNPS 2. Refer to Table A1.1 for NPS and DN pipe size equivalents.

Pipe Wall Thickness

Schedule is expressed in numbers (5, 5S, 10, 10S, 20, 20S, 30, 40, 40S, 60, 80, 80S,100, 120, 140, 160). A schedule number indicates the approximate value of theexpression 1000 P/S, where P is the service pressure and S is the allowable stress,both expressed in pounds per square inch (psi). The higher the schedule number,the thicker the pipe is. The outside diameter of each pipe size is standardized.Therefore, a particular nominal pipe size will have a different inside diameterdepending upon the schedule number specified.

Note that the original pipe wall thickness designations of STD, XS, and XXShave been retained; however, they correspond to a certain schedule number de-pending upon the nominal pipe size. The nominal wall thickness of NPS 10 andsmaller schedule 40 pipe is same as that of STD. WT. pipe. Also, NPS 8 and smallerschedule 80 pipe has the same wall thickness as XS pipe.

The schedule numbers followed by the letter S are per ASME B36.19M, andthey are primarily intended for use with stainless steel pipe. The pipe wall thicknessspecified by a schedule number followed by the letter S may or may not be thesame as that specified by a schedule number without the letter S. Refer to ASMEB36.19M and ASME B36.10M.10,11

ASME B36.19M does not cover all pipe sizes. Therefore, the dimensional require-ments of ASME B36.10M apply to stainless steel pipe of the sizes and schedulesnot covered by ASME B36.19M.

PIPING CLASSIFICATION

It is usual industry practice to classify the pipe in accordance with the pressure-temperature rating system used for classifying flanges. However, it is not essential


TABLE A1.2 Piping Class Ratings Based on ASME B16.5 and Corresponding PNDesignators

Class 150 300 400 600 900 1500 2500

PN 20 50 68 110 150 260 420

Notes:

1. Pressure-temperature ratings of different classes vary with the temperature and the material of con-struction.

2 For pressure-temperature ratings, refer to tables in ASME B16.5, or ASME B16.34.

that piping be classified as Class 150, 300, 400, 600, 900, 1500, and 2500. The pipingrating must be governed by the pressure-temperature rating of the weakest pressure-containing item in the piping. The weakest item in a piping system may be a fittingmade of weaker material or rated lower due to design and other considerations.Table A1.2 lists the standard pipe class ratings based on ASME B16.5 along withcorresponding pression nominal (PN) rating designators. Pression nominal is theFrench equivalent of pressure nominal.

In addition, the piping may be classified by class ratings covered by other ASMEstandards, such as ASME B16.1, B16.3, B16.24, and B16.42. A piping system maybe rated for a unique set of pressures and temperatures not covered by any standard.

Pression nominal (PN) is the rating designator followed by a designation number,which indicates the approximate pressure rating in bars. The bar is the unit ofpressure, and 1 bar is equal to 14.5 psi or 100 kilopascals (kPa). Table A1.2 providesa cross-reference of the ASME class ratings to PN rating designators. It is evidentthat the PN ratings do not provide a proportional relationship between differentPN numbers, whereas the class numbers do. Therefore, it is recommended thatclass numbers be used to designate the ratings. Refer to Chap. B2 for a moredetailed discussion of class rating of piping systems.

OTHER PIPE RATINGS

Manufacturers Rating

Based upon a unique or proprietary design of a pipe, fitting, or joint, the manufac-turer may assign a pressure-temperature rating that may form the design basis forthe piping system. Examples include Victaulic couplings and the Pressfit systemdiscussed in Chap. A9.

In no case shall the manufacturers rating be exceeded. In addition, the manufac-turer may impose limitations which must be adhered to.

NFPA Ratings

The piping systems within the jurisdiction of the National Fire Protection Associa-tion (NFPA) requirements are required to be designed and tested to certain requiredpressures. These systems are usually rated for 175 psi (1207.5 kPa), 200 psi (1380kPa), or as specified.


AWWA Ratings

The American Water Works Association (AWWA) publishes standards and speci-fications, which are used to design and install water pipelines and distribution systempiping. The ratings used may be in accordance with the flange ratings of AWWAC207, Steel Pipe Flanges; or the rating could be based upon the rating of the jointsused in the piping.

Specific or Unique Rating

When the design pressure and temperature conditions of a piping system do notfall within the pressure-temperature ratings of above-described rating systems, thedesigner may assign a specific rating to the piping system. Examples of such applica-tions include main steam or hot reheat piping of a power plant, whose designpressure and design temperature may exceed the pressure-temperature rating ofASME B16.5 Class 2500 flanges. It is normal to assign a specific rating to the piping.This rating must be equal to or higher than the design conditions. The rating of allpressure-containing components in the piping system must meet or exceed thespecific rating assigned by the designer.

Dual Ratings

Sometimes a piping system may be subjected to full-vacuum conditions or sub-merged in water and thus experience external pressure, in addition to withstandingthe internal pressure of the flow medium. Such piping systems must be rated forboth internal and external pressures at the given temperatures. In addition, a pipingsystem may handle more than one flow medium during its different modes ofoperation. Therefore, such a piping system may be assigned a dual rating for twodifferent flow media. For example, a piping system may have condensate flowingthrough it at some lower temperature during one mode of operation while steammay flow through it at some higher temperature during another mode of operation.It may be assigned two pressure ratings at two different temperatures.

GENERAL DEFINITIONS

Absolute Viscosity. Absolute viscosity or the coefficient of absolute viscosity isa measure of the internal resistance. In the centimeter, gram, second (cgs) or metricsystem, the unit of absolute viscosity is the poise (abbreviated P), which is equalto 100 centipoise (cP). The English units used to measure or express viscosity areslugs per foot-second or pound force seconds per square foot. Sometimes, theEnglish units are also expressed as pound mass per foot-second or poundal secondsper square foot. Refer to Chap. B8 of this handbook.

Adhesive Joint. A joint made in plastic piping by the use of an adhesive substancewhich forms a continuous bond between the mating surfaces without dissolvingeither one of them. Refer to Part D of this handbook.

Air-Hardened Steel. A steel that hardens during cooling in air from a temperatureabove its transformation range.1


Alloy Steel. A steel which owes its distinctive properties to elements other thancarbon. Steel is considered to be alloy steel when the maximum of the range givenfor the content of alloying elements exceeds one or more of the following limits2:

Manganese 1.65 percentSilicon 0.60 percentCopper 0.60 percent

or a definite range or a definite minimum quantity of any of the following elementsis specified or required within the limits of the recognized field of constructionalalloy steels:

Aluminum NickelBoron TitaniumChromium (up to 3.99 percent) TungstenCobalt VanadiumColumbium ZirconiumMolybdenum

or any other alloying element added to obtain a desired alloying effect.Small quantities of certain elements are unavoidably present in alloy steels. In

many applications, these are not considered to be important and are not specifiedor required. When not specified or required, they should not exceed the follow-ing amounts:

Copper 0.35 percentChromium 0.20 percentNickel 0.25 percentMolybdenum 0.06 percent

Ambient Temperature. The temperature of the surrounding medium, usually usedto refer to the temperature of the air in which a structure is situated or a device op-erates.

Anchor. A rigid restraint providing substantially full fixation, permitting neithertranslatory nor rotational displacement of the pipe.

Annealing. Heating a metal to a temperature above a critical temperature andholding above that range for a proper period of time, followed by cooling at asuitable rate to below that range for such purposes as reducing hardness, improvingmachinability, facilitating cold working, producing a desired microstructure, orobtaining desired mechanical, physical, or other properties.3 (A softening treatmentis often carried out just below the critical range which is referred to as a subcriti-cal annealing.)

Arc Cutting. A group of cutting processes in which the severing or removing ofmetals is effected by melting with the heat of an arc between an electrode and thebase metal (includes carbon, metal, gas metal, gas tungsten, plasma, and air carbonarc cutting). See also Oxygen Cutting.

Arc Welding. A group of welding processes in which coalescence is produced byheating with an electric arc or arcs, with or without the application of pressure andwith or without the use of filler metal.3,4


Assembly. The joining together of two or more piping components by bolting,welding, caulking, brazing, soldering, cementing, or threading into their installedlocation as specified by the engineering design.

Automatic Welding. Welding with equipment which performs the entire weldingoperation without constant observation and adjustment of the controls by an opera-tor. The equipment may or may not perform the loading and unloading of the work.3,5

Backing Ring. Backing in the form of a ring that can be used in the welding ofpiping to prevent weld spatter from entering a pipe and to ensure full penetrationof the weld to the inside of the pipe wall.

Ball Joint. A component which permits universal rotational movement in a pip-ing system.5

Base Metal. The metal to be welded, brazed, soldered, or cut. It is also referredto as parent metal.

Bell-Welded Pipe. Furnace-welded pipe produced in individual lengths from cut-length skelp, having its longitudinal butt joint forge-welded by the mechanicalpressure developed in drawing the furnace-heating skelp through a cone-shapeddie (commonly known as a welding bell), which serves as a combined forming andwelding die.

Bevel. A type of edge or end preparation.

Bevel Angle. The angle formed between the prepared edge of a member and aplane perpendicular to the surface of the member. See Fig. A1.1.

Blank Flange. A flange that is not drilled but is otherwise complete.

Blind Flange. A flange used to close the end of a pipe. It produces a blind endwhich is also known as a dead end.

Bond. The junction of the weld metal and the base metal, or the junction of thebase metal parts when weld metal is not present. See Fig. A1.2.

Branch Connection. The attachment of a branch pipe to the run of a main pipewith or without the use of fittings.

Braze Welding. A method of welding whereby a groove, fillet, plug, or slot weldis made using a nonferrous filler metal having a melting point below that of the

FIGURE A1.2 Bond between base metal andFIGURE A1.1 Bevel angle. weld metal.


base metals, but above 800F. The filler metal is not distributed in the joint bycapillary action.5 (Bronze welding, the term formerly used, is a misnomer.)

Brazing. A metal joining process in which coalescence is produced by use of anonferrous filler metal having a melting point above 800F but lower than that ofthe base metals joined. The filler metal is distributed between the closely fittedsurfaces of the joint by capillary action.5

Butt Joint. A joint between two members lying approximately in the same plane.5

Butt Weld. Weld along a seam that isbutted edge to edge. See Fig. A1.3.

Bypass. A small passage around alarge valve for warming up a line. Anemergency connection around a reduc-

FIGURE A1.3 A circumferential butt-ing valve, trap, etc., to use in case it iswelded joint.

out of commission.

Carbon Steel. A steel which owes its distinctive properties chiefly to the carbon(as distinguished from the other elements) which it contains. Steel is considered tobe carbon steel when no minimum content is specified or required for aluminum,boron, chromium, cobalt, columbium, molybdenum, nickel, titanium, tungsten, va-nadium, or zirconium or for any other element added to obtain a desired alloyingeffect; when the specified minimum for copper does not exceed 0.40 percent; orwhen the maximum content specified for any of the following elements does notexceed the percentages noted: manganese, 1.65 percent; silicon, 0.60 percent; copper,0.60 percent.2

Cast Iron. A generic term for the family of high carbon-silicon-iron casting alloysincluding gray, white, malleable, and ductile iron.

Centrifugally Cast Pipe. Pipe formed from the solidification of molten metal ina rotating mold. Both metal and sand molds are used. After casting, if requiredthe pipe is machined, to sound metal, on the internal and external diameters tothe surface roughness and dimensional requirements of the applicable material spec-ification.

Certificate of Compliance. A written statement that the materials, equipment, orservices are in accordance with the specified requirements. It may have to besupported by documented evidence.6

Certified Material Test Report (CMTR). A document attesting that the materialis in accordance with specified requirements, including the actual results of allrequired chemical analyses, tests, and examinations.6

Chamfering. The preparation of a contour, other than for a square groove weld,on the edge of a member for welding.

Cold Bending. The bending of pipe to a predetermined radius at any temperaturebelow some specified phase change or transformation temperature but especiallyat or near room temperature. Frequently, pipe is bent to a radius of 5 times thenominal pipe diameter.


Cold Working. Deformation of a metal plastically. Although ordinarily done atroom temperature, cold working may be done at the temperature and rate atwhich strain hardening occurs. Bending of steel piping at 1300F (704C) would beconsidered a cold-working operation.

Companion Flange. A pipe flange suited to connect with another flange or witha flanged valve or fitting. A loose flange which is attached to a pipe by threading,van stoning, welding, or similar method as distinguished from a flange which is castintegrally with a fitting or pipe.

Consumable Insert. Preplaced fillermetal which is completely fused into theroot of the joint and becomes part of theweld.1 See Fig. A1.4.

Continuous-Welded Pipe. Furnace-welded pipe produced in continuouslengths from coiled skelp and subse-quently cut into individual lengths, hav-ing its longitudinal butt joint forge-welded by the mechanical pressure de-veloped in rolling the hot-formed skelpthrough a set of round pass weldingrolls.3

Contractor. The entity responsible for FIGURE A1.4 Consumable insert ring in-furnishing materials and services for fab- serted in pipe joint eccentrically for welding inrication and installation of piping and horizontal position.associated equipment.

Control Piping. All piping, valves, and fittings used to interconnect air, gas, orhydraulically operated control apparatus or instrument transmitters and receivers.2

Controlled Cooling. A process of cooling from an elevated temperature in apredetermined manner to avoid hardening, cracking, or internal damage or toproduce a desired metallurgical microstructure. This cooling usually follows thefinal hot-forming or postheating operation.

Corner Joint. A joint between twomembers located approximately at rightangles to each other in the form of anL. See Fig. A1.5.

Coupling. A threaded sleeve used toconnect two pipes. Commercial cou-

FIGURE A1.5 Corner joint.plings have internal threads to fit exter-nal threads on pipe.

Covered Electrode. A filler metal electrode, used in arc welding, consisting of ametal core wire with a relatively thick covering which provides protection for themolten metal from the atmosphere, improves the properties of the weld metal, and


stabilizes the arc. Covered electrodes are extensively used in shop fabrication andfield erection of piping of carbon, alloy, and stainless steels.

Crack. A fracture-type imperfection characterized by a sharp tip and high ratioof length and depth to opening displacement.

Creep or Plastic Flow of Metals. At sufficiently high temperatures, all metalsflow under stress. The higher the temperature and stress, the greater the tendencyto plastic flow for any given metal.

Cutting Torch. A device used in oxygen, air, or powder cutting for controllingand directing the gases used for preheating and the oxygen or powder used forcutting the metal.

Defect. A flaw or an imperfection of such size, shape, orientation, location, orproperties as to be rejectable per the applicable minimum acceptance standards.7

Density. The density of a substance is the mass of the substance per unit volume.It may be expressed in a variety of units.

Deposited Metal. Filler metal that has been added during a welding operation.8

Depth of Fusion. The distance that fu-sion extends into the base metal fromthe surface melted during welding. SeeFig. A1.6.

FIGURE A1.6 Depth of fusion.Designer. Responsible for ensuringthat the engineering design of pipingcomplies with the requirements of the applicable code and standard and any addi-tional requirements established by the owner.

Dew Point. The temperature at which the vapor condenses when it is cooled atconstant pressure.

Dilatant Liquid. If the viscosity of a liquid increases as agitation is increased atconstant temperature, the liquid is termed dilatant. Examples are clay slurries andcandy compounds.

Discontinuity. A lack of continuity or cohesion; an interruption in the normalphysical structure of material or a product.7

Double Submerged Arc-Welded Pipe. Pipe having a longitudinal butt joint pro-duced by at least two passes, one of which is on the inside of the pipe. Coalescenceis produced by heating with an electric arc or arcs between the bare metal electrodeor electrodes and the work. The welding is shielded by a blanket of granular, fusiblematerial on the work. Pressure is not used, and filler metal for the inside and outsidewelds is obtained from the electrode or electrodes.

Ductile Iron. A cast ferrous material in which the free graphite is in a spheroidalform rather than a fluke form. The desirable properties of ductile iron are achievedby means of chemistry and a ferritizing heat treatment of the castings.


Eddy Current Testing. This is a nondestructive testing method in which eddycurrent flow is induced in the test object. Changes in the flow caused by variationsin the object are reflected into a nearby coil or coils for subsequent analysis bysuitable instrumentation and techniques.

Edge Joint. A joint between the edges of two or more parallel or nearly paral-lel members.

Edge Preparation. The contour pre-pared on the edge of a member for weld-ing. See Fig. A1.7.

Electric Flash-Welded Pipe. Pipe hav-ing a longitudinal butt joint in which co-alescence is produced simultaneously FIGURE A1.7 Edge preparation.over the entire area of abutting surfacesby the heat obtained from resistance tothe flow of electric current between the two surfaces and by the application ofpressure after heating is substantially completed. Flashing and upsetting are accom-panied by expulsion of metal from the joint.4

Electric Fusion-Welded Pipe. Pipe having a longitudinal or spiral butt joint inwhich coalescence is produced in the preformed tube by manual or automaticelectric arc welding. The weld may be single or double and may be made with orwithout the use of filler metal.4

Electric Resistance-Welded Pipe. Pipe produced in individual lengths or in contin-uous lengths from coiled skelp and subsequently cut into individual lengths havinga longitudinal butt joint in which coalescence is produced by the heat obtainedfrom resistance of the pipe to the flow of electric current in a circuit of which thepipe is a part and by the application of pressure.3

Electrode. See Covered Electrode.

End Preparation. The contour prepared on the end of a pipe, fitting, or nozzlefor welding. The particular preparation is prescribed by the governing code. Referto Chap. A6 of this handbook.

Engineering Design. The detailed design developed from process requirementsand conforming to established design criteria, including all necessary drawings andspecifications, governing a piping installation.5

Equipment Connection. An integral part of such equipment as pressure vessels,heat exchangers, pumps, etc., designed for attachment of pipe or piping components.8

Erection. The complete installation of a piping system, including any field assem-bly, fabrication, testing, and inspection of the system.5

Erosion. Destruction of materials by the abrasive action of moving fluids, usuallyaccelerated by the presence of solid particles.9

Examination. The procedures for all visual observation and nondestructivetesting.5


Expansion Joint. A flexible piping component which absorbs thermal and/orterminal movement.5

Extruded Nozzles. The forming of nozzle (tee) outlets in pipe by pulling hemi-spherically or conically shaped dies through a circular hole from the inside of thepipe. Although some cold extruding is done, it is generally performed on steel afterthe area to be shaped has been heated to temperatures between 2000 and 1600F(1093 and 871C).

Extruded Pipe. Pipe produced from hollow or solid round forgings, usually in ahydraulic extrusion press. In this process the forging is contained in a cylindricaldie. Initially a punch at the end of the extrusion plunger pierces the forging. Theextrusion plunger then forces the contained billet between the cylindrical die andthe punch to form the pipe, the latter acting as a mandrel.

One variation of this process utilizes autofrettage (hydraulic expansion) andheat treatment, above the recrystallization temperature of the material, to producea wrought structure.

Fabrication. Primarily, the joining of piping components into integral pieces readyfor assembly. It includes bending, forming, threading, welding, or other operationsupon these components, if not part of assembly. It may be done in a shop or inthe field.5

Face of Weld. The exposed surface of a weld on the side from which the weldingwas done.5,8

Filler Metal. Metal to be added in welding, soldering, brazing, or braze welding.8

Fillet Weld. A weld of an approximately triangular cross section joining twosurfaces approximately at right angles to each other in a lap joint, tee joint, cornerjoint, or socket weld.5 See Fig. A1.8.

Fire Hazard. Situation in which a material of more than average combustibilityor explodibility exists in the presence of a potential ignition source.5

Flat-Land Bevel. A square extended root face preparation extensively used ininert-gas, root-pass welding of piping. See Fig. A1.9.

FIGURE A1.8 Fillet weld. FIGURE A1.9 Flat-land bevel.


FIGURE A1.10 Welding in the flat position.

Flat Position. The position of welding which is performed from the upper sideof the joint, while the face of the weld is approximately horizontal. See Fig. A1.10.

Flaw. An imperfection of unintentional discontinuity which is detectable by anondestructive examination.7

Flux. Material used to dissolve, prevent accumulation of, or facilitate removal ofoxides and other undesirable substances during welding, brazing, or soldering.

Flux-Cored Arc Welding (FCAW ). An arc welding process that employs a contin-uous tubular filler metal (consumable) electrode having a core of flux for shielding.Adding shielding may or may not be obtained from an externally supplied gas orgas mixture.

Forge Weld. A method of manufacture similar to hammer welding. The termforge welded is applied more particularly to headers and large drums, while hammerwelded usually refers to pipe.

Forged and Bored Pipe. Pipe produced by boring or trepanning of a forged billet.

Full-Fillet Weld. A fillet weld whose size is equal to the thickness of the thinnermember joined.8

Fusion. The melting together of filler and base metal, or of base metal only, whichresults in coalescence.8

Fusion Zone. The area of base metalmelted as determined on the cross sec-tion of a weld. See Fig. A1.11.

Galvanizing. A process by which the FIGURE A1.11 Fusion zone is the section ofsurface of iron or steel is covered with the parent metal which melts during the weld-a layer of zinc. ing process.

Gas Metal Arc Welding (GMAW ). An arc welding process that employs a contin-uous solid filler metal (consumable) electrode. Shielding is obtained entirely froman externally supplied gas or gas mixture.4,8 (Some methods of this process havebeen called MIG or CO2 welding.)

Gas Tungsten Arc Welding (GTAW ). An arc welding process that employs atungsten (nonconsumable) electrode. Shielding is obtained from a gas or gas mix-


ture. Pressure may or may not be used, and filler metal may or may not be used.(This process has sometimes been called TIG welding.) When shielding is obtainedby the use of an inert gas such as helium or argon, this process is called inert-gastungsten arc welding.8

Gas Welding. Welding process in which coalescence is produced by heating witha gas flame or flames, with or without the application of pressure and with orwithout the use of filler metal.4

Groove. The opening provided for a groove weld.

Groove Angle. The total included angle of the groove between parts to be joinedby a groove weld. See Fig. A1.12.

FIGURE A1.12 The groove angle is twice theFIGURE A1.13 A groove face.bevel angle.

Groove Face. That surface of a member included in the groove. See Fig. A1.13.

Groove Radius. The radius of a J or U groove. See Fig. A1.14.

Groove Weld. A weld made in the groove between two members to be joined.The standard type of groove welds are square, single-V, single-bevel, single-U,single-J, double-V, double-U, double-bevel, double-J, and flat-land single, and dou-ble-V groove welds. See Fig. A1.15 for a typical groove weld.

FIGURE A1.15 Groove weld.FIGURE A1.14 A groove radius.

Hammer Weld. Method of manufacturing large pipe (usually NPS 20 or DN 500and larger) by bending a plate into circular form, heating the overlapped edges toa welding temperature, and welding the longitudinal seam with a power hammerapplied to the outside of the weld while the inner side is supported on an over-hung anvil.

Hangers and Supports. Hangers and supports include elements which transfer theload from the pipe or structural attachment to the supporting structure or equipment.They include hanging-type fixtures such as hanger rods, spring hangers, sway braces,counterweights, turnbuckles, struts, chains, guides, and anchors and bearing-typefixtures such as saddles, bases, rollers, brackets, and sliding supports.5 Refer toChap. B5 of this handbook.


Header. A pipe or fitting to which a number of branch pipes are connected.

Heat-Affected Zone. That portion of the base metal which has not been meltedbut whose mechanical properties or microstructure has been altered by the heatof welding or cutting.8 See Fig. A1.16.

FIGURE A1.17 Horizontal position filletFIGURE A1.16 Welding zones. weld.

Heat Fusion Joint. A joint made in thermoplastic piping by heating the partssufficiently to permit fusion of the materials when the parts are pressed together.

Horizontal Fixed Position. In pipe welding, the position of a pipe joint in whichthe axis of the pipe is approximately horizontal and the pipe is not rotated duringthe operation.

Horizontal-Position Fillet Weld. Welding is performed on the upper side of anapproximately horizontal surface and against an approximately vertical surface. SeeFig. A1.17.

Horizontal-Position Groove Weld. The position of welding in which the weldaxis lies in an approximately horizontal plane and the face of the weld lies in anapproximately vertical plane. See Fig. A1.18.

FIGURE A1.18 Horizontal position grooveweld. FIGURE A1.19 Horizontal rolled position.

Horizontal Rolled Position. The position of a pipe joint in which welding isperformed in the flat position by rotating the pipe. See Fig. A1.19.

Hot Bending. Bending of piping to a predetermined radius after heating to asuitably high temperature for hot working. On many pipe sizes, the pipe is firmlypacked with sand to avoid wrinkling and excessive out-of-roundness.

Hot Taps. Branch piping connections made to operating pipelines, mains, or otherfacilities while they are in operation.


Hot Working. The plastic deformation of metal at such a temperature and ratethat strain hardening does not occur. Extruding or swaging of chrome-moly pipingat temperatures between 2000 and 1600F (1093 and 871C) would be consideredhot-forming or hot-working operations.

Hydraulic Radius. The ratio of area of flowing fluid to the wetted perimeter.

Impact Test. A test to determine the behavior of materials when subjected tohigh rates of loading, usually in bending, tension, or torsion. The quantity measuredis the energy absorbed in breaking the specimen by a single blow, as in Charpy orIzod tests.

Imperfection. A condition of being imperfect; a departure of a quality characteris-tic from its intended condition.5

Incomplete Fusion. Fusion which is less than complete and which does not resultin melting completely through the thickness of the joint.

Indication. The response or evidence from the application of a nondestructive ex-amination.5

Induction Heating. Heat treatment of completed welds in piping by means ofplacing induction coils around the piping. This type of heating is usually performedduring field erection in those cases where stress relief of carbon- and alloy-steelfield welds is required by the applicable code.

Inspection. Activities performed by an authorized inspector to verify whether anitem or activity conforms to specified requirements.

Instrument Piping. All piping, valves, and fittings used to connect instruments tomain piping, to other instruments and apparatus, or to measuring equipment.2

Interpass Temperature. In a multiple-pass weld, the minimum or maximum tem-perature of the deposited weld metal before the next pass is started.

Interrupted Welding. Interruption of welding and preheat by allowing the weldarea to cool to room temperature as generally permitted on carbon-steel and onchrome-moly alloy-steel piping after sufficient weld passes equal to at least one-third of the pipe wall thickness or two weld layers, whichever is greater, havebeen deposited.

Joint. A connection between two lengths of pipe or between a length of pipe anda fitting.

Joint Penetration. The minimumdepth a groove weld extends from itsface into a joint, exclusive of reinforce-ment.5 See Fig. A1.20.

Kinematic Viscosity. The ratio of theabsolute viscosity to the mass density. FIGURE A1.20 Weld joint penetration.In the metric system, kinematic viscosityis measured in strokes or square centimeters per second. Refer to Chap. B8 ofthis handbook.


Laminar Flow. Fluid flow in a pipe is usually considered laminar if the Reynoldsnumber is less than 2000. Depending upon many possible varying conditions, theflow may be laminar at a Reynolds number as low as 1200 or as high as 40,000;however, such conditions are not experienced in normal practice.

Lap Weld. Weld along a longitudinal seam in which one part is overlapped bythe other. A term used to designate pipe made by this process.

Lapped Joint. A type of pipe joint made by using loose flanges on lengths of pipewhose ends are lapped over to give a bearing surface for a gasket or metal-to-metal joint.

Liquid Penetrant Examination or Inspection. This is a nondestructive examina-tion method for finding discontinuities that are open to the surface of solid andessentially nonporous materials. This method is based on capillary action or capillaryattraction by which the surface of a liquid in contact with a solid is elevated ordepressed. A liquid penetrant, usually a red dye, is applied to the clean surface ofthe specimen. Time is allowed for the penetrant to seep into the opening. Theexcess penetrant is removed from the surface. A developer, normally white, isapplied to aid in drawing the penetrant up or out to the surface. The red penetrantis drawn out of the discontinuity, which is located by the contrast and distinctappearance of the red penetrant against the white background of the developer.

Local Preheating. Preheating of a specific portion of a structure.

Local Stress-Relief Heat Treatment. Stress-relief heat treatment of a specificportion of a weldment. This is done extensively with induction coils, resistancecoils, or propane torches in the field erection of steel piping.

Machine Welding. Welding with equipment which performs the welding operationunder the observation and control of an operator. The equipment may or may notperform the loading and unloading of the work.

Magnetic Particle Examination or Inspection. This is a nondestructive examina-tion method to locate surface and subsurface discontinuities in ferromagnetic materi-als. The presence of discontinuities is detected by the use of finely divided ferromag-netic particles applied over the surface. Some of these magnetic particles aregathered and held by the magnetic leakage field created by the discontinuity. Theparticles gathered at the surface form an outline of the discontinuity and generallyindicate its location, size, shape, and extent.

Malleable Iron. Cast iron which has been heat-treated in an oven to relieve itsbrittleness. The process somewhat improves the tensile strength and enables thematerial to stretch to a limited extent without breaking.

Manual Welding. Welding wherein the entire welding operation is performedand controlled by hand.5

Mean Velocity of Flow. Under steady state of flow, the mean velocity of flow ata given cross section of pipe is equal to the rate of flow Q divided by the area ofcross section A. It is expressed in feet per second or meters per second.


where v mean velocity of flow, in feet per second, ft/s (meters per second, m/s)Q rate of flow, in cubic feet per second, ft3/s (cubic meters per second,

m3/s)A area of cross section, in square feet, ft2 (square meters, m2)

Mechanical Joint. A joint for the purpose of mechanical strength or leak resistanceor both, where the mechanical strength is developed by threaded, grooved, rolled,flared, or flanged pipe ends or by bolts, pins, and compounds, gaskets, rolled ends,caulking, or machined and mated surfaces. These joints have particular applicationwhere ease of disassembly is desired.5

Mill Length. Also known as random length. The usual run-of-mill pipe is 16 to20 ft (5 to 6 m) in length. Line pipe and pipe for power plant use are sometimesmade in double lengths of 30 to 35 ft (10 to 12 m).

Miter. Two or more straight sections of pipe matched and joined on a line bisectingthe angle of junction so as to produce a change in direction.4

Newtonian Liquid. A liquid is called newtonian if its viscosity is unaffected bythe kind and magnitude of motion or agitation to which it may be subjected, aslong as the temperature remains constant. Water and mineral oil are examples ofnewtonian liquids.

Nipple. A piece of pipe less than 12 in (0.3 m) long that may be threaded onboth ends or on one end and provided with ends suitable for welding or a mechanicaljoint. Pipe over 12 in (0.3 m) long is regarded as cut pipe. Common types of nipplesare close nipple, about twice the length of a standard pipe thread and without anyshoulder; shoulder nipple, of any length and having a shoulder between the pipethreads; short nipple, a shoulder nipple slightly longer than a close nipple and ofa definite length for each pipe size which conforms to manufacturer standard; longnipple, a shoulder nipple longer than a short nipple which is cut to a specific length.

Nominal Diameter (DN ). A dimensionless designator of pipe in metric system.It indicates standard pipe size when followed by the specific size designation numberwithout the millimeter symbol (for example, DN 40, DN 300).

Nominal Pipe Size (NPS). A dimensionless designator of pipe. It indicates stan-dard pipe size when followed by the specific size designation number without aninch symbol (for example, NPS 1, NPS 12).2

Nominal Thickness. The thickness given in the product material specification orstandard to which manufacturing tolerances are applied.5

Nondestructive Examination or Inspection. Inspection by methods that do notdestroy the item, part, or component to determine its suitability for use.

Normalizing. A process in which a ferrous metal is heated to a suitable tempera-ture above the transformation range and is subsequently cooled in still air atroom temperature.5


Nozzle. As applied to piping, this term usually refers to a flanged connection ona boiler, tank, or manifold consisting of a pipe flange, a short neck, and a weldedattachment to the boiler or other vessel. A short length of pipe, one end of whichis welded to the vessel with the other end chamfered for butt welding, is alsoreferred to as a welding nozzle.

Overhead Position. The position of welding performed from the underside ofthe joint.

Oxidizing Flame. An oxyfuel gas flame having an oxidizing effect caused byexcess oxygen.

Oxyacetylene Cutting. An oxygen-cutting process in which metals are severed bythe chemical reaction of oxygen with the base metal at elevated temperatures. Thenecessary temperature is maintained by means of gas flames obtained from thecombustion of acetylene with oxygen.

Oxyacetylene Welding. A gas welding process in which coalescence is producedby heating with a gas flame or flames obtained from the combustion of acetylenewith oxygen, with or without the addition of filler metal.

Oxyfuel Gas Welding (OFGW ). A group of welding processes in which coales-cence is produced by heating with a flame or flames obtained from the combustionof fuel gas with oxygen, with or without the application of pressure and with orwithout the use of filler metal.

Oxygen Cutting (OC). A group of cutting processes used to sever or removemetals by means of the reaction of oxygen with the base metal at elevated tempera-tures. In the case of oxidation-resistant metals, the reaction is facilitated by use ofa chemical flux or metal powder.8

Oxygen Gouging. An application of oxygen cutting in which a chamfer or grooveis formed.

Pass. A single progression of a welding or surfacing operation along a joint, welddeposit, or substrate. The result of a pass is a weld bead, layer, or spray deposit.8

Peel Test. A destructive method of examination that mechanically separates a lapjoint by peeling.8

Peening. The mechanical working of metals by means of hammer blows.

Pickle. The chemical or electrochemical removal of surface oxides. Followingwelding operations, piping is frequently pickled in order to remove mill scale, oxidesformed during storage, and the weld discolorations.

Pipe. A tube with a round cross section conforming to the dimensional require-ments for nominal pipe size as tabulated in ASME B36.10M and ASME B36.19M.For special pipe having diameter not listed in the above-mentioned standards, thenominal diameter corresponds to the outside diameter.5

Pipe Alignment Guide. A restraint in the form of a sleeve or frame that permitsthe pipeline to move freely only along the axis of the pipe.8


Pipe Supporting Fixtures. Elements that transfer the load from the pipe or struc-tural attachment to the support structure or equipment.8

Pipeline or Transmission Line. A pipe installed for the purpose of transmittinggases, liquids, slurries, etc., from a source or sources of supply to one or moredistribution centers or to one or more large-volume customers; a pipe installed tointerconnect source or sources of supply to one or more distribution centers or toone or more large-volume customers; or a pipe installed to interconnect sourcesof supply.2

Piping System. Interconnected piping subject to the same set or sets of design con-ditions.1

Plasma Cutting. A group of cutting processes in which the severing or removalof metals is effected by melting with a stream of hot ionized gas.1

Plastic. A material which contains as an essential ingredient an organic substanceof high to ultrahigh molecular weight, is solid in its finished state, and at some stageof its manufacture or processing can be shaped by flow. The two general types ofplastic are thermoplastic and thermosetting.

Polarity. The direction of flow of current with respect to the welding electrodeand workpiece.

Porosity. Presence of gas pockets or voids in metal.

Positioning Weld. A weld made in a joint which has been so placed as to facilitatethe making of the weld.

Postheating. The application of heat to a fabricated or welded section subsequentto a fabrication, welding, or cutting operation. Postheating may be done locally, asby induction heating; or the entire assembly may be postheated in a furnace.

Postweld Heat Treatment. Any heat treatment subsequent to welding.5

Preheating. The application of heat to a base metal immediately prior to a weldingor cutting operation.5

Pressure. The force per unit that is acting on a real or imaginary surface within afluid is the pressure or intensity of pressure. It is expressed in pounds per square inch:

where p absolute pressure at a point, psi (kg/cm2)w specific weight, lb/ft3 (kg/m3)h height of fluid column above the point, ft (m)

pa atmospheric pressure, psi (kg/cm2)


The gauge pressure at a point is obtained by designating atmospheric pressureas zero:

where p gauge pressure. To obtain absolute pressure from gauge pressure, addthe atmospheric pressure to the gauge pressure.

Pressure Head. From the definition of pressure, the expression p/w is the pressurehead. It can be defined as the height of the fluid above a point, and it is normallymeasured in feet.

Purging. The displacement during welding, by an inert or neutral gas, of theair inside the piping underneath the weld area in order to avoid oxidation orcontamination of the underside of the weld. Gases most commonly used are argon,helium, and nitrogen (the last is principally limited to austenitic stainless steel).Purging can be done within a complete pipe section or by means of purging fixturesof a small area underneath the pipe weld.

Quenching. Rapid cooling of a heated metal.

Radiographic Examination or Inspection. Radiography is a nondestructive testmethod which makes use of short-wavelength radiations, such as X-rays or gammarays, to penetrate objects for detecting the presence and nature of macroscopicdefects or other structural discontinuities. The shadow image of defects or disconti-nuities is recorded either on a fluorescent screen or on photographic film.

Reinforcement. In branch connections, reinforcement is material around a branchopening that serves to strengthen it. The material is either integral in the branchcomponents or added in the form of weld metal, a pad, a saddle, or a sleeve. Inwelding, reinforcement is weld metal in excess of the specified weld size.

Reinforcement Weld. Weld metal on the face of a groove weld in excess of themetal necessary for the specified weld size.5

Repair. The process of physically restoring a nonconformance to a condition suchthat an item complies with the applicable requirements, including the code require-ments.6

Resistance Weld. Method of manufacturing pipe by bending a plate into circularform and passing electric current through the material to obtain a welding temper-ature.

Restraint. A structural attachment, device, or mechanism that limits movementof the pipe in one or more directions.8

Reverse Polarity. The arrangement of direct-current arc welding leads with thework as the negative pole and the electrode as the positive pole of the welding arc;a synonym for direct-current electrode positive.8


Reynolds Number. A dimensionless number. It is defined as the ratio of thedynamic forces of mass flow to the shear stress due to viscosity. It is expressed as

where R Reynolds numberv mean velocity of flow, ft/s (m/s) weight density of fluid, lb/ft3 (kg/m3)

D internal diameter of pipe, ft (m) absolute viscosity, in pound mass per foot second [lbm/(ft s)] or poundal

seconds per square foot (centipoise)

Rolled Pipe. Pipe produced from a forged billet which is pierced by a conicalmandrel between two diametrically opposed rolls. The pierced shell is subsequentlyrolled and expanded over mandrels of increasingly large diameter. Where closerdimensional tolerances are desired, the rolled pipe is cold- or hot-drawn throughdies and then machined. One variation of this process produces the hollow shellby extrusion of the forged billet over a mandrel in a vertical, hydraulic piercing press.

Root Edge. A root face of zero width.

Root Face. That portion of the groove face adjacent to the root of the joint. Thisportion is also referred to as the root land. See Fig. A1.21.

FIGURE A1.21 Nomenclature at joint of groove weld.

Root of Joint. That portion of a joint to be welded where the members to bejoined come closest to each other. In cross section, the root of a joint may be apoint, a line, or an area. See Fig. A1.21.

Root Opening. The separation, between the members to be joined, at the rootof the joint.5 See Fig. A1.21.

Root Penetration. The depth which a groove weld extends into the root of a jointas measured on the centerline of the root cross section. Sometimes welds areconsidered unacceptable if they show incomplete penetration. See Fig. A1.21.


Root Reinforcement. Weld reinforcement at the side other than that from whichthe welding was done.

Root Surface. The exposed surface of a weld on the side other than that fromwhich the welding was done.

Run. The portion of a fitting having its end in line, or nearly so, as distinguishedfrom branch connections, side outlets, etc.

Saddle Flange. Also known as tank flange or boiler flange. A curved flange shapedto fit a boiler, tank, or other vessel and to receive a threaded pipe. A saddle flangeis usually riveted or welded to the vessel.

Sample Piping. All piping, valves, and fittings used for the collection of samplesof gas, steam, water, oil, etc.2

Sargol. A special type of joint in which a lip is provided for welding to make thejoint fluid tight, while mechanical strength is provided by bolted flanges. The Sargoljoint is used with both Van Stone pipe and fittings.

Sarlun. An improved type of Sargol joint.

Schedule Numbers. Approximate values of the expression 1000P/S, where P isthe service pressure and S is the allowable stress, both expressed in pounds persquare inch.

Seal Weld. A fillet weld used on a pipe joint primarily to obtain fluid tightnessas opposed to mechanical strength; usually used in conjunction with a threaded joint.8

Seamless Pipe. A wrought tubular product made without a welded seam. It ismanufactured by hot-working steel or, if necessary, by subsequently cold-finishingthe hot-worked tubular product to produce the desired shape, dimensions, and prop-erties.

Semiautomatic Arc Welding. Arc welding with equipment which controls onlythe filler metal feed. The advance of the welding is manually controlled.3

Semisteel. A high grade of cast iron made by the addition of steel scrap to pipiron in a cupola or electric furnace. More correctly described as high-strengthgray iron.

Service Fitting. A street ell or street tee having a male thread at one end.

Shielded Metal Arc Welding (SMAW ). An arc welding process in which coales-cence is produced by heating with an electric arc between a covered metal electrodeand the work. Shielding is obtained from decomposition of the electrode covering.Pressure is not used, and filler metal is obtained from the electrode.8

Shot Blasting. Mechanical removal of surface oxides and scale on the pipe innerand outer surfaces by the abrasive impingement of small steel pellets.


Singl