1、AWS C3.3:2008An American National StandardRecommendedPractices forthe Design,Manufacture, andExamination ofCritical BrazedComponents550 N.W. LeJeune Road, Miami, FL 33126AWS C3.3:2008An American National StandardApproved by theAmerican National Standards InstituteApril 21, 2008Recommended Practices
2、for theDesign, Manufacture, and Examinationof Critical Brazed Components3rd EditionSupersedes AWS C3.3:2002Prepared by theAmerican Welding Society (AWS) C3 Committee on Brazing and SolderingUnder the Direction of theAWS Technical Activities CommitteeApproved by theAWS Board of DirectorsAbstractThis
3、standard lists the necessary steps to assure the suitability of brazed components for critical applications. Althoughsuch applications vary widely, they have certain common considerations with respect to materials, design, manufacture,and inspection. It is the intent of this document to identify and
4、 explain these common considerations and the best tech-niques for dealing with them. It is beyond the scope of this document to provide specific details on these techniques,which the user must adapt to fit each particular application.iiAWS C3.3:2008International Standard Book Number: 978-0-87171-092
5、-5American Welding Society550 N.W. LeJeune Road, Miami, FL 33126 2008 by American Welding SocietyAll rights reservedPrinted in the United States of AmericaPhotocopy Rights. No portion of this standard may be reproduced, stored in a retrieval system, or transmitted in anyform, including mechanical, p
6、hotocopying, recording, or otherwise, without the prior written permission of the copyrightowner.Authorization 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 Weldi
7、ng Society provided that the appropriatefee is paid to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, tel: (978) 750-8400; Internet:.iiiAWS C3.3:2008Statement on the Use of American Welding Society StandardsAll standards (codes, specifications, recommended practices, methods,
8、 classifications, and guides) of the AmericanWelding Society (AWS) are voluntary consensus standards that have been developed in accordance with the rules of theAmerican National Standards Institute (ANSI). When AWS American National Standards are either incorporated in, ormade part of, documents th
9、at are included in federal or state laws and regulations, or the regulations of other govern-mental bodies, their provisions carry the full legal authority of the statute. In such cases, any changes in those AWSstandards must be approved by the governmental body having statutory jurisdiction before
10、they can become a part ofthose laws and regulations. In all cases, these standards carry the full legal authority of the contract or other documentthat invokes the AWS standards. Where this contractual relationship exists, changes in or deviations from requirementsof an AWS standard must be by agree
11、ment between the contracting parties.AWS American National Standards are developed through a consensus standards development process that bringstogether volunteers representing varied viewpoints and interests to achieve consensus. While the AWS administers theprocess and establishes rules to promote
12、 fairness in the development of consensus, it does not independently test, evalu-ate, or verify 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, wh
13、etherspecial, indirect, consequential, or compensatory, directly or indirectly resulting from the publication, use of, or relianceon this standard. AWS also makes no guarantee or warranty as to the accuracy or completeness of any informationpublished herein.In issuing and making this standard availa
14、ble, AWS is neither undertaking to render professional or other services for oron behalf 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
15、, seek theadvice of a competent professional in determining the exercise of reasonable care in any given circumstances. It isassumed that the use of this standard and its provisions are entrusted to appropriately qualified and competent personnel.This standard may be superseded by the issuance of ne
16、w 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 acceptany and all liabilities for infringement of any patent or trade name items. AWS disclaims liability for the infring
17、ement ofany patent or product trade name resulting from the use of this standard.Finally, the AWS does not monitor, police, or enforce compliance with this standard, nor does it have the power to do so.On occasion, text, tables, or figures are printed incorrectly, constituting errata. Such errata, w
18、hen discovered, are postedon 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 appropriate technical committee. Such requests should be addressed to the American Welding Society,A
19、ttention: Managing Director, Technical Services Division, 550 N.W. LeJeune Road, Miami, FL 33126 (see Annex F).With regard to technical inquiries made concerning AWS standards, oral opinions on AWS standards may be rendered.These opinions are offered solely as a convenience to users of this standard
20、, and they do not constitute professionaladvice. Such opinions represent only the personal opinions of the particular individuals giving them. These individualsdo not speak on behalf of AWS, nor do these oral opinions constitute official or unofficial opinions or interpretations ofAWS. In addition,
21、oral opinions are informal and should not be used as a substitute for an official interpretation.This standard is subject to revision at any time by the AWS C3 Committee on Brazing and Soldering. It must bereviewed every five years, and if not revised, it must be either reaffirmed or withdrawn. Comm
22、ents (recommendations,additions, or deletions) and any pertinent data that may be of use in improving this standard are required and should beaddressed to AWS Headquarters. Such comments will receive careful consideration by the AWS C3 Committee onBrazing and Soldering and the author of the comments
23、 will be informed of the Committees response to the comments.Guests are invited to attend all meetings of the AWS C3 Committee on Brazing and Soldering to express their commentsverbally. Procedures for appeal of an adverse decision concerning all such comments are provided in the Rules ofOperation o
24、f the Technical Activities Committee. A copy of these Rules can be obtained from the American WeldingSociety, 550 N.W. LeJeune Road, Miami, FL 33126.This page is intentionally blank.ivAWS C3.3:2008vAWS C3.3:2008PersonnelAWS C3 Committee on Brazing and SolderingP. T. Vianco, Chair Sandia National Lab
25、oratoriesR. W. Smith, Vice Chair Materials Resources InternationalS. N. Borrero, Secretary American Welding SocietyG. L. Alexy The Prince Table 2, which identifies design considerations with respect to brazeability; Table 3,which identifies metallurgical aspects of brazeability; Annex D, which provi
26、des information on braze-induced disconti-nuities and inspection methods; Annex E, which presents brazement design criteria; and Annex F, which presents guide-lines for the preparation of inquiries to AWS technical committees.Comments and suggestions for the improvement of this standard are welcome.
27、 These should be sent to the Secretary,AWS C3 Committee on Brazing and Soldering, American Welding Society, 550 N.W. LeJeune Road, Miami, FL 33126.This page is intentionally blank.viiiAWS C3.3:2008ixAWS C3.3:2008Table of ContentsPage No.PersonnelvForeword viiList of Tables xList of Figures.x1. Scope
28、.12. Normative References .13. Terms and Definitions.14. Brazing Materials14.1 Filler Metals.14.2 Form.24.3 Fluxes.24.4 Packaging and Storage.24.5 Identification25. Design .25.1 Basic Considerations .25.2 Qualification of Brazers and Processes .25.3 Application 25.4 Documentation.25.5 Materials 35.6
29、 Configuration.45.7 Brazing Process Selection45.8 Postbrazing Operations45.9 Acceptance Criteria .65.10 Systematic Criteria in Brazement Design65.11 Strength of the Brazed Joints.66. Manufacture 66.1 Facilities and Equipment .66.2 Procedures77. Examination.87.1 Introduction87.2 Common Discontinuitie
30、s in Brazed Joints 87.3 Examination Methods for Brazed Joints9Annex A (Informative)Informative References .13Annex B (Informative)Sample Specifications for Specific Critical Components15Annex C (Informative)Brazing Risk Management 21Annex D (Informative)Inspection: Quantification of the Scope and Ma
31、gnitude of Braze-InducedAnnex D (Informative)Discontinuities.23Annex E (Informative)Brazement Design Criteria.25Annex F (Informative)Guidelines for the Preparation of Technical Inquiries .29List of AWS Documents on Brazing and Soldering 31xAWS C3.3:2008List of TablesTable Page No.1 Filler Metal Sele
32、ction32 Primary Aspects of Brazeability as Impacted by Joint Features and Configuration 43 Primary Metallurgical Aspects of Brazeability 5D.1 Inspection and Quality of Brazed Joints .23List of FiguresFigure Page No.C.1 Brazing Risks and Process Variables21AWS C3.3:200811. ScopeThese recommended prac
33、tices encompass those proce-dures that should be followed in the design, manufacture,and examination of brazed joints for critical componentsin order to assure their reliability in service.The procedures recommended represent the best currentpractice and are necessary to the control of brazed jointq
34、uality. These practices are applicable to all products andbrazing processes. Whenever any or some of these prac-tices are omitted when producing critical components,the omission should be the result of a rational decision,not the result of a lack of knowledge of the best practice.This document is di
35、vided into clauses addressing mate-rials, design, manufacturing, and examination. Theseclauses are followed by Annex A, which presents a list ofinformative references; Annex B, which presents samplespecifications that are intended as guides for the prepara-tion of the users documents; Annex C, which
36、 presents adiscussion of brazing risk management; Annex D, whichpresents a table relating to the quantification of the scopeand magnitude of braze-induced discontinuities; AnnexE, which presents systematic criteria for design of brazedcomponents; and Annex F, which presents guidelines forthe prepara
37、tion of inquiries for AWS technical committees.This standard does not require units of measure. There-fore, no equivalents or conversions are contained exceptwhen they are cited in examples.Procedures for the protection of the safety and health ofthose performing brazing and related operations are o
38、fgreat importance. Among the potential hazards to beconsidered are exposure to fumes and gases, radiation,and toxic materials. Safety and health issues may not befully addressed by this standard. Users of this standardshould consult ANSI Z49.1, Safety in Welding, Cutting,and Allied Processes, applic
39、able federal, state, and localregulations and other relevant documents concerningsafety and health issues not addressed herein. Additionalinformation on safety and health is included in the Amer-ican Welding Society Brazing Handbook.2. Normative ReferencesThe standards listed below contain provision
40、s, which,through reference in this text, constitute mandatory pro-visions of this AWS standard. For undated references,the latest edition of the referenced standard shall apply.For dated references, subsequent amendments to, or revi-sions of, any of these publications do not apply.American Welding S
41、ociety standard:1AWS A3.0:2001, Standard Welding Terms and Defi-nitions, Including Terms for Adhesive Bonding, Brazing,Soldering, Thermal Cutting, and Thermal Spraying3. Terms and DefinitionsAWS A3.0, Standard Welding Terms and Definitions,Including Terms for Adhesive Bonding, Brazing, Solder-ing, T
42、hermal Cutting, and Thermal Spraying, providesthe basis for terminology used herein.For the purposes of this document, the following termand definition applies:critical component. A component whose primary fail-ure would cause significant danger to persons orproperty or would result in a significant
43、 operationalpenalty.4. Brazing Materials4.1 Filler Metals. The brazing filler metal to be usedas well as its quantity, dimensions, and placementshould be specified on the engineering drawing oraccompanying documents and should meet the require-ments of AWS A5.8, Specification for Filler Metals forBr
44、azing and Braze Welding, unless otherwise specified1AWS standards are published by the American WeldingSociety, 550 N.W. LeJeune Road, Miami, FL 33126.Recommended Practices for the Design, Manufacture,and Examination of Critical Brazed ComponentsAWS C3.3:20082by the engineering drawing or accompanyi
45、ng docu-ments. Each incoming lot, batch, or heat of brazing fillermetal should be verified to the specification. Identifica-tion and traceability should be provided.4.2 Form. Brazing filler metals are available in severaldifferent physical shapes and sizes that should be speci-fied by the user as fo
46、llows:(1) Wire: Diameter, length, and dimensions of theformed shapes; temper, if for use in automatic feedingequipment;(2) Foil: Thickness, width, and length; temper, if foruse in automatic feeding equipment;(3) Powder: Particle size or size distribution, or both;(4) Paste: Binder type and percentag
47、e, and powderparticle size;(5) Plasticized tape: Thickness, width, percent den-sity, and binder type;(6) Brazing sheet: Cladding thickness and composi-tion; and(7) Plating: Electrolytic or electroless, and thickness.4.3 Fluxes. For information on fluxes, refer to AWSA5.31, Specification for Fluxes f
48、or Brazing and BrazeWelding.4.4 Packaging and Storage. The methods of packagingto prevent contamination or the loss of identificationshould be specified. Storage conditions and shelf lifeshould be specified, when appropriate.4.5 Identification. Procedures should be established tomaintain the integri
49、ty of the identification of materialsduring use.5. Design5.1 Basic Considerations. Reliability requires deliberatesteps during the design phase to assure the effective con-trol of quality. Quality control procedures must not beafterthoughts that are specified once the design is final-ized, they should be developed concurrently with thedesign and verified as appropriate. Consideration shouldbe given to the practical aspects of brazing, the charac-teristics of the filler and base materials involved, and thelimitations of the inspection procedures.The requirements of the brazing and ins
