1、RecommendedPractices forAir CarbonArc Gougingand CuttingAWS C5.3:2000An American National Standard550 N.W. LeJeune Road, Miami, Florida 33126AWS C5.3:2000An American National StandardApproved byAmerican National Standards InstituteNovember 21, 2000Recommended Practices forAir Carbon Arc Gouging and
2、CuttingSupersedes ANSI/AWS C5.3-91Prepared byAWS C5 Committee on Arc Welding and CuttingUnder the Direction ofAWS Technical Activities CommitteeApproved byAWS Board of DirectorsAbstractThis publication establishes a method of conveying to the welder/operator the proper setup and use of air carbon ar
3、cgouging and cutting. Instructions and procedures are supplied in detail so the welder/operator can establish the correctair pressure, amperage, voltage, and techniques.Key WordsAir carbon arc, gouging, cutting, recommended practicesStatement on Use of AWS American National StandardsAll standards (c
4、odes, specifications, recommended practices, methods, classifications, and guides) of the AmericanWelding Society are voluntary consensus standards that have been developed in accordance with the rules of the AmericanNational Standards Institute. When AWS standards are either incorporated in, or mad
5、e part of, documents that areincluded in federal or state laws and regulations, or the regulations of other governmental bodies, their provisions carrythe full legal authority of the statute. In such cases, any changes in those AWS standards must be approved by thegovernmental body having statutory
6、jurisdiction before they can become a part of those laws and regulations. In allcases, these standards carry the full 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 stan
7、dard must be byagreement between the contracting parties.International Standard Book Number: 0-87171-630-5American Welding Society, 550 N.W. LeJeune Road, Miami, FL 33126 2001 by American Welding Society. All rights reservedPrinted in the United States of AmericaAWS American National Standards are d
8、eveloped through a consensus standards development process that bringstogether volunteers representing varied viewpoints and interests to achieve consensus. While AWS administers the processand establishes rules to promote fairness in the development of consensus, it does not independently test, eva
9、luate, orverify the 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 spe-cial, indirect, consequential or compensatory, directly or indirectly
10、resulting from the publication, use of, or reliance on thisstandard. 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 onb
11、ehalf of any person or entity. Nor is AWS undertaking to perform any duty owed by any person or entity to someoneelse. Anyone using these documents should rely on his or her own independent judgment or, as appropriate, seek the adviceof a competent professional in determining the exercise of reasona
12、ble care in any 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. AWS disclaims liability for the infringementof any patent resulting f
13、rom the use or reliance on this standard.Finally, AWS does not monitor, police, or enforce compliance with this standard, nor does it have the power to do so.Official interpretations of any of the technical requirements of this standard may be obtained by sending a request, in writ-ing, to the Manag
14、ing Director Technical Services, 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 maybe rendered. However, such opinions represent only the personal opinions of the particul
15、ar individuals giving them. Theseindividuals do not speak on behalf of AWS, nor do these oral opinions constitute official or unofficial opinions or interpre-tations of AWS. In addition, oral opinions are informal and should not be used as a substitute for an official interpretation.This standard is
16、 subject to revision at any time by the AWS C5 Committee on Arc Welding and Cutting. It must be re-viewed every five years and if not revised, it must be either reapproved or withdrawn. Comments (recommendations, addi-tions, or deletions) and any pertinent data that may be of use in improving this s
17、tandard are required and should beaddressed to AWS Headquarters. Such comments will receive careful consideration by the AWS C5 Committee on ArcWelding 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
18、the AWS C5 Committee on Arc Welding and Cutting to express their com-ments verbally. Procedures for appeal of an adverse decision concerning all such comments are provided in the Rules ofOperation of the Technical Activities Committee. A copy of these Rules can be obtained from the American WeldingS
19、ociety, 550 N.W. LeJeune Road, Miami, FL 33126.Photocopy RightsAuthorization to photocopy items for internal, personal, or educational classroom use only, or the internal, personal, oreducational classroom use only of specific clients, is granted by the American Welding Society (AWS) provided that t
20、heappropriate fee is paid to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, Tel: 978-750-8400;online: http:/.iiiPersonnelAWS C5 Committee on Arc Welding and CuttingB. L. Shultz, Chair The Taylor Winfield Corp.J. R. Hannahs, 1st Vice Chair ConsultantN. E. Larson, 2nd Vice Chai
21、r ConsultantC. R. Fassinger, Secretary American Welding Society*D. B. Arthur J. W. Harris-Welco*E. R. Bohnart Welding Education and ConsultingH. A. Chambers TRW Nelson Stud Welding DivisionC. Connelly ConsultantD. A. Fink The Lincoln Electric CompanyI. D. Harris Edison Welding Institute*R. T. Hemzac
22、ek ConsultantG. K. Hicken Sandia National Laboratory*J. E. Hinkel The Lincoln Electric CompanyD. B. Holliday Northrop Grumman Corp.S. R. Potter ConsultantN. A. Sanders HyperthermR. L. Strohl Tweco-ArcairE. G. Yevick Weld-Met International GroupAWS Subcommittee on Air Carbon Arc CuttingR. L. Strohl,
23、Chair Tweco-ArcairC. R. Fassinger, Secretary American Welding SocietyJ. DeVito ESAB Wldg and Cutting ProductsB. L. Shultz The Taylor Winfield Corp.G. Snyder Tri-County Vocational Schools*AdvisorivForeword(This Foreword is not a part of AWS C5.3:2000, Recommended Practices for Air Carbon Arc Gouging
24、and Cutting,but is included for information purposes only.)These recommended practices have been prepared by the Subcommittee on Air Carbon Arc Cutting, of the AWS ArcWelding and Cutting Committee. It is important to recognize that this publication does not present the only possibleconditions for us
25、ing the air carbon arc cutting process. The data given are presented merely as guides in establishingoperating conditions.Comments and suggestions for the improvement of this standard are welcome. They should be sent to the Secretary,AWS C5 Committee on Arc Welding and Cutting, American Welding Soci
26、ety, 550 N.W. LeJeune Road, Miami, FL33126.vTable of ContentsPage No.Personnel iiiForewordivList of Tables.viiList of Figures.vii1. General 11.1 Scope.11.2 Description11.3 History 11.4 Applications 12. Referenced Standards23. Fundamentals of the Process.23.1 General23.2 Power Sources.23.3 Compressed
27、 Air 23.4 Electrodes23.5 Gouging and Cutting Leads 43.6 Manual Cutting Torches43.7 Mechanized Cutting Torches 43.8 Vacuum Gouging 64. Operating Techniques64.1 Gouging 64.2 Cutting 84.3 Washing.84.4 Beveling 85. Equipment Selection .85.1 Cutting Torch 85.2 Power Sources.85.3 Mechanized Systems.106. P
28、rocess Variables.106.1 Introduction.106.2 Electrode Diameter and Type106.3 Amperage106.4 Voltage 106.5 Air Pressure and Flow Rate 126.6 Travel Speed126.7 Electrode Push Angle126.8 Base Metals.127. Advantages and Limitations137.1 Advantages137.2 Limitations 14viPage No.8. Troubleshooting.149. Safe Pr
29、actices 149.1 Introduction.149.2 Noise .149.3 Gases.159.4 Radiant Energy1610. Bibliography16Annex ACommonly Used Metric Conversion17Annex BSafety References.19Annex CGuidelines for Preparation of Technical Inquiries for AWS Technical Committees .21AWS List of Documents on Arc Welding and Cutting .23
30、viiList of TablesTable Page No.1 Recommended Minimum Air Requirements .42 Recommended Number and Size of Gouging and Cutting Leads for Various Currents and Lengths.53 Suggested Current Ranges for Commonly Used Electrode Types and Sizes 64 Mechanized CAC-A U-Groove Gouging Conditions 115 Automatic CA
31、C-A J-Groove Operating Data 116 Primary Process Variables127 Gouging Recommendations.138 Results of Corrosion Testing on Type 304L Stainless Steel 149 CAC-A Troubleshooting 1510 Particulate Matter with Possible Significant Fume Concentration in the Arc Cutters Breathing Zone16List of FiguresFigure P
32、age No.1 Typical Arrangement for the Air Carbon Arc Cutting Process32 How a Standard CAC-A Torch Works .33 Manual Torch .54 Mechanized Cutting Torch.65 Flat Position Gouging 76 Vertical Position Gouging 77 Horizontal Position Gouging .78 Overhead Position Gouging .79 Severing/Piercing with CAC-A910
33、Pad Washing with CAC-A .911 Methods of Beveling with CAC-A.10AWS C5.3:200011. General1.1 Scope. This publication presents the basic conceptsof the air carbon arc cutting (CAC-A)1process to providea fundamental understanding of the process and its vari-ables. In addition, specific technical data are
34、presented asa guide in establishing optimum operation of this process.This standard makes use of the U.S. Customary Units.Approximate mathematical equivalents in the Interna-tional System of Units (SI) are provided for comparisonin parentheses ( ) or in appropriate columns in tables andfigures. Anne
35、x A is included to identify metric equivalentsif the reader requires precise conversion information.Safety and health issues and concerns are beyond thescope of this standard and, therefore, are not fully ad-dressed herein. Some safety and health information canbe found in Section 9. Safety and heal
36、th information isavailable from other sources, including, but not limitedto, ANSI Z49.1, Safety in Welding, Cutting, and AlliedProcesses, and applicable federal and state regulations.1.2 Description. CAC-A is a physical means of metalremoval in contrast to the oxidation reaction in oxyfuelgas cuttin
37、g (OFC). In the CAC-A, the intense heat of thearc between the carbon electrode and the workpiece meltsa portion of the workpiece. Simultaneously, a jet of air ispassed parallel to the arc and is of sufficient volume andvelocity to blow away the molten material. The exposedsolid metal is then melted
38、by the heat of the arc, and thesequence continues.CAC-A does not depend on oxidation to maintain thecut, so it is capable of cutting metals that OFC will notcut. The process is used successfully on carbon steel,stainless steel, many copper alloys, and cast irons. Themelting rate is a function of cur
39、rent. The metal removalrate is dependent upon the melting rate and the efficiency1. CAC-A (Carbon Arc Cutting-Air) was formerly AAC (AirArc Cutting).of the air jet in removing the molten metal. The air mustbe capable of lifting the molten metal out and clear of thearc region before resolidification.
40、1.3 History. CAC-A was developed in the 1940s as anextension of an existing processcarbon arc cutting.Faced with the removal, in the flat position, of severalhundred feet of cracked stainless steel weld, a weldingengineer developed CAC-A. Carbon arc cutting was usedto remove defective welds and rive
41、t heads, but only in theoverhead and vertical positions. The carbon arc meltedthe metal and gravity moved the molten metal out of thearea. It was reasoned that an air jet could provide the forceto remove the metal in the flat position.A direct current electrode negative (DCEN) carbon arcwas tried, a
42、nd an air blast was provided by the secondcutter with an air nozzle directed at the pool. This attemptwas not very successful because the arc was not stable.Direct current electrode positive (DCEP) was tried, andthe result made air carbon arc cutting practical. The basicprinciple remains the same to
43、day, but the equipment andapplications have been improved and expanded.In 1948, the first air carbon arc torch was introduced tothe welding industry. No longer were two cutters needed.The air was fed through the torch and out beneath theelectrode at the correct location. This new tool was foundto sa
44、ve time on backgouging of welds and removal ofcracks and other weld defects on carbon, alloy, and stain-less steels. Previously, this type of work had been done bygrinding or chipping. As the use of the CAC-A expanded,torches were designed for more efficient and cleaner metalremoval and for cutter c
45、omfort.1.4 Applications. The CAC-A process is used through-out industry in a variety of applications, such as metalfabrication and casting finishing, chemical and petro-leum technology, construction, mining, general repair,and maintenance. CAC-A torches and electrodes are usedto create groove weld p
46、reparations in plates butted to-gether. If the process is performed properly a minimalRecommended Practices forAir Carbon Arc Gouging and CuttingAWS C5.3:20002amount of additional cleaning and grinding is required.The CAC-A process can then be used to backgouge thejoint to sound metal to ensure comp
47、lete joint penetration.If during welding, a problem arises and an area of theweld does not meet specifications, the CAC-A processcan be used to remove the defective weld metal withoutdamaging or detrimentally affecting the base metal. TheCAC-A process is used in the foundry industry to removefins an
48、d risers from castings and then used to wash thecontact areas smooth with the surface in preparation forshipment of the casting. The air carbon arc process pre-sents great flexibility, efficiency, and cost effectivenesswhen applied to practically any type of metal. Carbonsteel, stainless steel, gray
49、, malleable, and ductile iron,aluminum, nickel, copper alloys, and other nonferrousmetals can be worked on with CAC-A.2. Referenced StandardsThe following standards contain provisions which,through reference in the text, constitute provisions of thisAWS standard. For dated references, subsequent amend-ments to, or revisions of, any of these publications do notapply. However, parties to agreements based on this AWSstandard are encouraged to investigate the possibility ofapplying the most recent editions of the documents shownbelow. For undated references, the latest ed