1、Recommended Practices for Electrogas Welding AWS C5.7:2000 (R2006) An American National Standard550 N.W. LeJeune Road, Miami, FL 33126 AWS C5.7:2000 (R2006) An American National Standard Approved by the American National Standards Institute May 5, 2000 Recommended Practices for Electrogas Welding Su
2、persedes ANSI/AWS C5.7-89 Prepared by the American Welding Society (AWS) C5 Committee on Arc Welding and Cutting Under the Direction of the AWS Technical Activities Committee Approved by the AWS Board of Directors Abstract Electrogas Welding (EGW) is a specialized welding process having similarities
3、 to the gas metal arc welding (GMAW) or the flux cored arc welding (FCAW) processes for vertical position welding. The electrode deposits filler metal in the cavity formed by backing plates or shoes that bridge the groove between the plates being welded. The elec- trode may be solid, metal cored, or
4、 flux cored, and additional shielding may or may not be obtained from an externally supplied gas or gas mixture. The weld is usually completed in a single pass. Fundamentals of the process, including the various methods of welding, are presented. A discussion of equipment, consumables, applications,
5、 and metallurgical advantages and limitations is provided. The selection of process variables and operating conditions and typical EGW procedures is then presented. Inspection of welds, and training and qualifica- tion of welding procedures and operators are described. Finally, a troubleshooting gui
6、de, safety considerations, and a supplementary reading list are presented.ii AWS C5.7:2000 (R2006) International Standard Book Number: 0-87171-575-9 American Welding Society 550 N.W. LeJeune Road, Miami, FL 33126 2000 by American Welding SocietyAll rights reserved Printed in the United States of Ame
7、rica Reaffirmed: October 16, 2006 Photocopy Rights. No portion of this standard may be reproduced, stored in a retrieval system, or transmitted in any form, including mechanical, photocopying, recording, or otherwise, without the prior written permission of the copyright owner. Authorization to phot
8、ocopy items for internal, personal, or educational classroom use only or the internal, personal, or educational classroom use only of specific clients is granted by the American Welding Society provided that the appropriate fee is paid to the Copyright Clearance Center, 222 Rosewood Drive, Danvers,
9、MA 01923, tel: (978) 750-8400; Internet: .iii AWS C5.7:2000 (R2006) Statement on the Use of American Welding Society Standards All standards (codes, specifications, recommended practices, methods, classifications, and guides) of the American Welding Society (AWS) are voluntary consensus standards th
10、at have been developed in accordance with the rules of the American National Standards Institute (ANSI). When AWS American National Standards are either incorporated in, or made part of, documents that are included in federal or state laws and regulations, or the regulations of other govern- mental
11、bodies, their provisions carry the full legal authority of the statute. In such cases, any changes in those AWS standards must be approved by the governmental body having statutory jurisdiction before they can become a part of those laws and regulations. In all cases, these standards carry the full
12、legal authority of the contract or other document that invokes the AWS standards. Where this contractual relationship exists, changes in or deviations from requirements of an AWS standard must be by agreement between the contracting parties. AWS American National Standards are developed through a co
13、nsensus standards development process that brings together volunteers representing varied viewpoints and interests to achieve consensus. While AWS administers the process and establishes rules to promote fairness in the development of consensus, it does not independently test, evaluate, or verify th
14、e accuracy of any information or the soundness of any judgments contained in its standards. AWS disclaims liability for any injury to persons or to property, or other damages of any nature whatsoever, whether special, indirect, consequential or compensatory, directly or indirectly resulting from the
15、 publication, use of, or reliance on this standard. AWS also makes no guaranty or warranty as to the accuracy or completeness of any information published herein. In issuing and making this standard available, AWS is not undertaking to render professional or other services for or on behalf of any pe
16、rson or entity. Nor is AWS undertaking to perform any duty owed by any person or entity to someone else. Anyone using these documents should rely on his or her own independent judgment or, as appropriate, seek the advice of a competent professional in determining the exercise of reasonable care in a
17、ny given circumstances. This standard may be superseded by the issuance of new editions. Users should ensure that they have the latest edition. Publication of this standard does not authorize infringement of any patent or trade name. Users of this standard accept any and all liabilities for infringe
18、ment of any patent or trade name items. AWS disclaims liability for the infringement of any patent or product trade name resulting from the use of this standard. Finally, AWS does not monitor, police, or enforce compliance with this standard, nor does it have the power to do so. On occasion, text, t
19、ables, or figures are printed incorrectly, constituting errata. Such errata, when discovered, are posted on the AWS web page (www.aws.org). Official interpretations of any of the technical requirements of this standard may only be obtained by sending a request, in writing, to the Managing Director,
20、Technical Services Division, American Welding Society, 550 N.W. LeJeune Road, Miami, FL 33126 (see Annex C). With regard to technical inquiries made concerning AWS standards, oral opinions on AWS standards may be rendered. However, such opinions represent only the personal opinions of the particular
21、 individuals giving them. These individuals do not speak on behalf of AWS, nor do these oral opinions constitute official or unofficial opinions or interpretations of AWS. In addition, oral opinions are informal and should not be used as a substitute for an official interpretation. This standard is
22、subject to revision at any time by the AWS C5 Committee on Arc Welding and Cutting. It must be reviewed every five years, and if not revised, it must be either reaffirmed or withdrawn. Comments (recommendations, additions, or deletions) and any pertinent data that may be of use in improving this sta
23、ndard are required and should be addressed to AWS Headquarters. Such comments will receive careful consideration by the AWS C5 Committee on Arc Welding and Cutting and the author of the comments will be informed of the Committees response to the comments. Guests are invited to attend all meetings of
24、 the AWS C5 Committee on Arc Welding and Cutting to express their comments verbally. Procedures for appeal of an adverse decision concerning all such comments are provided in the Rules of Operation of the Technical Activities Committee. A copy of these Rules can be obtained from the American Welding
25、 Society, 550 N.W. LeJeune Road, Miami, FL 33126.This page is intentionally blank. iv AWS C5.7:2000 (R2006)v AWS C5.7:2000 (R2006) Personnel (Reaffirmation) *Advisor AWS C5 Committee on Arc Welding and Cutting N. A. Sanders, Chair Hypertherm, Incorporated D. B. Holliday, Vice Chair Northrop Grumman
26、Corporation R. M. Dull, 2nd Vice Chair Edison Welding Institute B. C. McGrath, Secretary American Welding Society *E. R. Bohnart Welding Education & Consulting R. D. Campbell Bechtel National, Incorporated *R. M. Campbell Consultant H. A. Chambers Consultant J. D. Colt Hypertherm, Incorporated C. Co
27、nnelly Poly-Weld J. DeVito ESAB D. A. Fink The Lincoln Electric Company J. R. Hannahs Consultant *I. D. Harris Edison Welding Institute *R. T. Hemzacek Consultant G. K. Hicken Sandia National Labs K. Y. Lee The Lincoln Electric Company R. P. Munz The Lincoln Electric Company S. R. Potter SSP Consult
28、ing Services F. A. Schweighardt Air Liquide Industrial US, LP R. L. Strohl Tweco Products E. G. Yevick Weld-Met International Group A. P. Yost The Lincoln Electric Company AWS C5P Subcommittee on Electrogas Welding K. Y. Lee, Chair The Lincoln Electric Company B. C. McGrath, Secretary American Weldi
29、ng Society J. H. Devletian Portland State University D. A. Fink The Lincoln Electric Company *J. R. Hannahs Consultant *W. M. Kavicky Trans Bay Steel Corporation J. S. Lee Chicago Bridge and Iron Company, Incorporated *R. D. Thomas, Jr. R D Thomas & CompanyThis page is intentionally blank. vi AWS C5
30、.7:2000 (R2006)vii AWS C5.7:2000 (R2006) Personnel (Original) *Advisor AWS C5 Committee on Arc Welding and Cutting J. R. Hannahs, Chair Consultant N. E. Larson, Vice Chair Consultant M. O. Kulp, Jr., Secretary American Welding Society *D. B. Arthur J. W. Harris Welco *E. R. Bohnart Welding Education
31、 and Consulting H. A. Chambers TRW Nelson Stud Welding Division C. Connelly Consultant R. M. Dull Edison Welding Institute D. A. Fink The Lincoln Electric Company I. D. Harris Edison Welding Institute *R. T. Hemzacek Consultant G. K. Hicken Sandia National Laboratory *J. E. Hinkel Lincoln Electric C
32、ompany D. B. Holliday Northrop Grumman Corporation R. P. Munz The Lincoln Electric Company S. R. Potter Consultant N. A. Sanders Hypertherm *B. L. Shultz The Taylor Winfield Corporation R. L. Strohl Tweco/Arcair E. G. Yevick Weld-Met International Group AWS C5P Subcommittee on Electrogas Welding D.
33、A. Fink, Chair The Lincoln Electric Company M. O. Kulp, Jr., Secretary American Welding Society J. H. Devletian Oregon Graduate Institute *J. R. Hannahs Consultant R. H. Juers Naval Surface Warfare Center *W. M. Kavicky Trans Bay Steel Corporation D. Y. Ku American Bureau of Shipping J. S. Lee Chica
34、go Bridge and Iron Company, Incorporated *B. L. Shultz The Taylor Winfield Corporation *R. D. Thomas, Jr. R. D. Thomas and Company *L. D. Smith ConsultantThis page is intentionally blank. viii AWS C5.7:2000 (R2006)ix AWS C5.7:2000 (R2006) Foreword This foreword is not part of AWS C5.7:2000 (R2006),
35、Recommended Practices for Electrogas Welding, but is included for informational purposes only. Electrogas welding (EGW) was introduced as a practical fabricating process in 1961. In recent years, advances have been made so that electrogas welding is now accepted as an efficient and practical method
36、in some metal joining appli- cations. EGW applications should continue to expand as fabricators become more familiar with the fundamentals, tech- niques, and advantages of this welding process. The increased usage and interest in EGW prompted the American Welding Society to sponsor this Recommended
37、Practices for Electrogas Welding. Sufficient data have been gathered and organized to yield an authoritative source of sound technical practices for electrogas welding. Accordingly, the AWS C5 Committee on Arc Welding and Cutting has prepared these recommended practices as compiled by the Subcommitt
38、ee on Electrogas Welding. These recommended practices are based on a survey of electrogas welding as used in the metal fabricating and construction industry. The description of electrogas welding and its features is presented here as clearly and concisely as possible. The Committee has developed the
39、se guidelines in the hope that they will lead to further development of the electrogas welding process and thus, to higher quality and performance standards. Comments and suggestions for the improvement of this standard are welcome. They should be sent to the Secretary, AWS C5 Committee on Arc Weldi
40、ng and Cutting, American Welding Society, 550 N.W. LeJeune Road, Miami, FL 33126.This page is intentionally blank. x AWS C5.7:2000 (R2006)xi AWS C5.7:2000 (R2006) Table of Contents Page No. Personnel (Reaffirmation)v Personnel (Original) vii Foreword .ix List of Tables xiii List of Figuresxiv 1. Gen
41、eral .1 1.1 Scope 1 1.2 Introduction 1 2. Referenced Standards.1 3. Definitions 3 4. Fundamentals 5 4.1 Process Description 5 4.2 Principles of Operation.5 4.3 Electrode Variations .5 4.4 Consumable Guide Variations6 5. Equipment9 5.1 Welding Power Source.9 5.2 Wire (Electrode) Feeder .9 5.3 Electro
42、de Guide Oscillators9 5.4 Electrode Guide9 5.5 Backing Shoes (Dams) .9 5.6 Controls 10 6. Electrodes and Shielding Gas.10 6.1 Electrodes .10 6.2 Shielding.10 6.3 AWS Specification for Electrogas Filler Metal10 7. Applications .10 7.1 Base Metals 10 7.2 Joint Design11 7.3 Assembly and Alignment .11 7
43、.4 Typical Applications 14 8. Metallurgical Advantages and Limitations.14 8.1 Electrogas Welding Thermal Cycle14 8.2 Weld Macrostructure22 8.3 Preheat 23 8.4 Postweld Heat Treatment .24 8.5 Residual Stresses and Distortion 24 8.6 Mechanical Properties 24 9. Selection of Process Variables and Other W
44、elding Conditions 27 9.1 Welding Voltage.27 9.2 Welding CurrentWire Feed Speed27xii Page No. AWS C5.7:2000 (R2006) 9.3 Form Factor 27 9.4 Electrode Extension29 9.5 Electrode Oscillation 29 9.6 Joint Opening29 9.7 Work Lead30 9.8 EGW Procedures 30 10. Inspection of Welds and Rework .30 10.1 Methods o
45、f Inspection 30 10.2 Acceptance .30 10.3 Quality Control.30 10.4 Rework .30 11. Training45 11.1 Process Variables45 11.2 Equipment Familiarization .47 12. Qualifications.47 12.1 Process and Equipment.47 12.2 Welding Procedure .47 12.3 Welding Operator .47 13. Troubleshooting Guide .47 13.1 Weld Star
46、t Porosity.47 13.2 Weld Porosity .47 13.3 Weld Termination Porosity 48 13.4 Centerline Weld Cracking 48 13.5 Incomplete Fusion at Weld Toes48 13.6 Incomplete Fusion to One Groove Face.48 13.7 Overlap and Poor Fusion48 13.8 Underfill .48 13.9 Starting Tab Melt-Through.48 13.10 Copper Pickup 48 13.11
47、Metal Spillage.48 13.12 Electrode Wander .49 13.13 Arcing to Groove Faces49 13.14 Hourglass Nugget Shape 49 14. Safety Recommendations49 14.1 Radiant Energy .49 14.2 Burn Protection.50 14.3 Electrical Hazards.50 14.4 Fumes and Gases 50 14.5 Noise and Hearing Protection.51 14.6 Safety and Health Info
48、rmation Sources51 Annex A (Informative)Safety and Health References53 Annex B (Informative)Supplementary Reading List .55 Annex C (Informative)Guidelines for the Preparation of Technical Inquiries.57 List of AWS Documents on Arc Welding and Cutting59xiii AWS C5.7:2000 (R2006) List of Tables Table Pa
49、ge No. 1 Chemical Composition Requirements for Solid Electrodes 11 1A Chemical Composition Requirements for Weld Metal From Composite Flux Cored and Metal Cored Electrodes12 2 A5.26 Tension Test Requirements (As-Welded).13 2M A5.26M Tension Test Requirements (As-Welded) .13 3 A5.26 Impact Test Requirements (As-Welded).13 3M A5.26M Impact Test Requirements (As-Welded) .13 4 Typical As-Welded Mechanical Properties of Structural Steels Welded with Self-Shielded Flux Cored Electrodes25 5 Typical As-Welded Mechanical Properties of Steels Welded with Gas Shielded Flux Cored Electrodes.26 6 As
