1、BRITISH STANDARD BS EN ISO 18279:2003 Brazing Imperfections in brazed joints The European Standard EN ISO 18279:2003 has the status of a British Standard ICS 25.160.50 BS EN ISO 18279:2003 This British Standard was published under the authority of the Standards Policy and Strategy Committee on 16 Ja
2、nuary 2004 BSI 16 January 2004 ISBN 0 580 43238 6 National foreword This British Standard is the official English language version of EN ISO 18279:2003. It is identical with ISO 18279:2003. The UK participation in its preparation was entrusted to Technical Committee WEE/19, Brazing and bronze weldin
3、g, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Catalogue under th
4、e section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct applicat
5、ion. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monit
6、or related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN ISO title page, pages 2 to 28, an inside back cover and a back cover. The BSI copyright notice displayed in this document indicates
7、when the document was last issued. Amendments issued since publication Amd. No. Date CommentsEUROPEANSTANDARD NORMEEUROPENNE EUROPISCHENORM ENISO18279 August2003 ICS25.160.50 Englishversion BrazingImperfectionsinbrazedjoints(ISO18279:2003) BrasagefortDfautsdanslesassemblagesralisspar brasagefort(ISO
8、18279:2003) HartltenUnregelmigkeiteninhartgelteten Verbindungen(ISO18279:2003) ThisEuropeanStandardwasapprovedbyCENon17March2003. CENmembersareboundtocomplywiththeCEN/CENELECInternalRegulationswhichstipulatetheconditionsforgivingthisEurope an Standardthestatusofanationalstandardwithoutanyalteration.
9、Uptodatelistsandbibliographicalreferencesconcernings uchnational standardsmaybeobtainedonapplicationtotheManagementCentreortoanyCENmember. ThisEuropeanStandardexistsinthreeofficialversions(English,French,German).Aversioninanyotherlanguagemadebytra nslation undertheresponsibilityofaCENmemberintoitsow
10、nlanguageandnotifiedtotheManagementCentrehasthesamestatusasthe official versions. CENmembersarethenationalstandardsbodiesofAustria,Belgium,CzechRepublic,Denmark,Finland,France,Germany,Greece, Hungary,Iceland,Ireland,Italy,Luxembourg,Malta,Netherlands,Norway,Portugal,Slovakia,Spain,Sweden,Switzerland
11、andUn ited Kingdom. EUROPEANCOMMITTEEFORSTANDARDIZATION COMITEUROPENDENORMALISATION EUROPISCHESKOMITEEFRNORMUNG ManagementCentre:ruedeStassart,36B1050Brussels 2003CEN Allrightsofexploitationinanyformandbyanymeansreserved worldwideforCENnationalMembers. Ref.No.ENISO18279:2003EINES:97281O3002(E) 2 Con
12、tents Page Foreword3 Introduction .4 1 Scope 5 2 Termsanddefinitions. .6 3 Symbols 7 4 Classification8 4.1 General8 4.2 Externalimperfections 8 4.3 Internalimperfections .8 AnnexA (informative) Guidelinesforpracticalevaluationofimperfections 20 AnnexB (informative) Evaluation 21 Bibliography 28 Page
13、2 ENISO18279:2003INES:97281O3002( E) 3 Foreword Thisdocument(ENISO18279:2003)hasbeenpreparedbyTechnicalCommitteeCEN/TC 121“Welding“,the secretariatofwhichisheldbyDS,incollaborationwithTechnicalCommitteeISO/TC44“Weldingandallied processes”. This EuropeanSt andard EN ISO18 279:2003sh all be given the
14、status ofana tionals tandard, either by publication ofanidenticaltextorbyendorsement,att helatest byJune2004andconflictingnationalstandardsshallbe withdrawn at the latest by June 2004. Annexes AandBar e informative. AccordingtotheCEN/CENELECInternalRegulations,thenationalstandardsorganizationsofthef
15、ollowing countriesareboundtoimplementthisEuro peanStandard:Austria,Belgium,CzechRepublic,Denmark,Finland, France,Germany,Greece,Hungary,Iceland,Ireland,Italy,Luxembourg,Malta,Netherlands,Norway,Portugal, Slovakia,S pain, Sweden,Swi tzerlandandtheUnitedKin gdom. Page3 ENISO18279:2003INES:97281O3002(E
16、) 4 Introduction Brazedjointsusuallycontainimperfectionsofvarioustypes,someofwhichwillbedetrimentalinalmosteverycase butothersmaybedetrimentalorharmless,dependingentirelyontheservicerequirementsofthejointinquestion. Thereforeitwillfrequentlybenecessarytoclassifytheimperfectionsinabrazedjointandthent
17、rytoassessthe significanceoftheireffectsonthebehaviourofthejointinservice.Theclassificationis,relatively,easyandTable1 describestheimperfectionsthatmostcommonlyoccur.Theassessmentofsignificanceisnoteasy(seealso AnnexA). Forweldedjoints,therehasbeenextensiveworkcarriedoutformanyyearsonthesignificance
18、ofimperfectionsin servicebutsuchworkhasnotbeencarriedoutonbrazedjoints.Moreovertheworkonweldedjointsisonlyrarely relevanttobrazedjoints,mainlybecauseofdifferencesingeometryandstressing.Thereforethisstandardcannot givedefinitivequalitylevelsforbrazedjoints.Thesecanonlybeproducedasexperienceisgainedfr
19、omindustrial applications.However,AnnexBgivessomesuggestionsforqualitylevelsforgeneralapplications,whichmaybeof helpwheredetailedinformationisnotavailable.Ithastobeemphasizedthattheuseofqualitylevelscanonlybe successfuliftheimperfectionsthatarerelevanttotheapplicationofthebrazedjointaredetermined. P
20、age4 ENISO18279:2003INES:97281O3002(E) 5 1Scope ThisEuropeanStandarddetailsaclassificationofimperfectionsthatcanoccurinbrazingjoints.Inaddition guidanceisprovidedonqualitylevelsandsuggestedlimitsforimperfectionsaredetailed. Forrequirementsnotcoveredbythisstandard,referenceistobemadetoothersources,e.
21、g.statutoryregulations, codesofpracticeandtechnicaldeliveryconditions. Noinformationisgivenonhowimperfectionsaretobeassessedinindividualcasesbecausethisdependsonthe requirementsfortheparticularbrazedjoint.Theseimperfectionsarenotalwaysdetectablebytheuseofnon destructivetestingalone. Thestandardcover
22、sonlyimperfectionsthatcanoccurinconnectionwithbrazingwithouttheeffectofany additionalserviceloads.Onlythetype,shapeandpositionofsuchimperfectionsarecovered;noindicationisgiven oftheconditionsofoccurrenceorcauses. Forrequirementsforbrazedjointswhicharerelevantandessentialtotheparticularfunctionofthec
23、omponent, referenceshouldbemadetotherelevantdocumentation,e.g.manufacturingdocumentsorproceduresheets. NOTE It is important that these requirements be precisely prescribed and that compliance with them be verifiable. Compliancemaybeestablishedbytestingeitherthebrazedassemblyitselforatestpieceproduce
24、dundercomparable conditions.Therequirementsshouldbeestablishedandfullydocumentedbeforeanyclassificationisundertaken. ThisEuropeanStandarddoesnotlaydownrequirementsforacceptancelevelsforimperfectionssincethesewill differverymarkedly,dependingontheapplication,butitdoessuggestsomequalitylevelswhichmayb
25、eofvaluein theabsenceofmoredetailedinformation. Page5 ENISO18279:2003INES:97281O3002(E) 6 a)Simplebrazedassembly Key Parentmaterial Parentmaterialaffectedbybrazing(heataffectedzone(HAZ) Diffusiontransitionzone Brazemetal NOTE ExtentofHAZwillvarywithmaterialsandbrazingprocess. b)Sectionthroughassembl
26、yina) Figure1Schematicofbrazedassembly 2 Termsanddefinitions ForthepurposesofthisEuropeanStandardtheareasofabrazedassemblyaredefinedasshownschematicallyin Figure1.Inadditionthefollowingtermanddefinitionapply. Page6 ENISO18279:2003INES:97281O3002(E) 7 2.1 imperfections irregularitiesinthebrazedjoint,
27、deviationsfromtheintendedrelativepositionsofthepartsjoinedbybrazingand fromtheintendedshapeofthebrazedcomponent,wheresuchdeviationsaredependentonthebrazing 3Symbols Thefollowingsymbolsareused: l lengthofthebrazedoverlap; l r requiredbrazedlength; l u lengthofoverlapbeforebrazing; l 1,2 dimensionsoft
28、hebrazedimperfection; t j thicknessofbrazedjoint; t 1,2 wallorplatethicknessorthicknesses. t t t l l l l l 1 j 2 1 2 r u NOTE Thisfigureillustratesaplanarimperfection. Figure2Symbolsusedfordimensions Page7 ENISO18279:2003INES:97281O3002(E) 8 4Classification 4.1General Theimperfectionsareclassifiedin
29、tosixgroupsasfollows: group I Cracks; group II Cavities; group IIISolid inclusions; group IVBonding imperfections; groupV Shapeandsizeimperfections; groupVI Miscellaneousimperfections. Imperfectionsareidentifiedbydesignations. Afurtherdistinctioncanbemadebetweentheexternalandinternalimperfectionstha
30、tmayoccurinbrazedjoints. 4.2Externalimperfections Externalimperfectionsinbrazedjointsinclude: underfill; cracks; surfacebreaking porosity; incompletefillet; overlap; localized melting; roughsurfaceofseam; flux seepage; discoloration; spatter; residual flux; surfaceerosionofparentmaterial. 4.3Interna
31、limperfections Internalimperfectionsinbrazedjointsinclude: cracks; filling imperfections; Page8 ENISO18279:2003INES:97281O3002(E) 9 solid inclusions; gas entrapment; flux inclusion; lack of fusion; excessivealloyingoffillermaterialandparentmaterial(sometimescallederosion). Page9 ENISO18279:2003INES:
32、97281O3002(E) 01 Table1Classificationofimperfections Designation Description Remarks Drawing ICracks 1A a AAA crack Limitedseparationofthematerial,predominantlytwo dimensionalextension.Acrackmaybelongitudinalor transverse Itcanlieinoneormoreofthefollowing: 1A a AAB inthebrazemetal 1A a AAC attheinte
33、rfaceandincludingthediffusionzone 1A a AAD IntheHAZ 1A a AAE intheunaffectedparentmaterial 1AAAD 1AAAE 1AAAC 1AAAB a Inthecaseofanintergranularcrack,changethissecondsymbolAtothesymbolF. Inthecaseofatransgranularcrack,changethissecondsymbolAtothesymbolH. Page10 ENISO18279:2003INES:97281O3002(E) 11 Ta
34、ble1Classificationofimperfections (continued) Designation Description Remarks Drawing IICavities 2AAAA cavity 2BAAA gascavity Gasfilledcavity 2BAAA 2BGAA gaspore Spheroidalgasinclusion. Itcanoccuras: 2BGGA uniformlydistributedporosity 2BGMA localized(clustered)porosity 2BGHA linearporosity 2LIAA lar
35、gegaspockets Largevoidsmaybethewidthofthejointwithelongated shape Page11 ENISO18279:2003INES:97281O3002(E) 21 Table1Classificationofimperfections (continued) Designation Description Remarks Drawing 2BALF b surfacepore Gasporebreakingthesurface. 2MGAF b surfacebubble Gasporenearthesurfacewhichresults
36、inswelling b Theseimperfectionsoftenoccurtogether. Page12 ENISO18279:2003INES:97281O3002(E) 31 Table1Classificationofimperfections (continued) Designation Description Remarks Drawing III.Solidinclusions 3AAAA solidinclusion Inclusionofforeignmetalornonmetallicparticlesinthe brazemetal Maybeposssible
37、todivideinto: 3DAAA oxideinclusion 3FAAA metallicinclusion 3CAAA fluxinclusion 3AAAA IVBondingimperfections 4BAAA bondingimperfection Nobondingorinadequatebondingbetweenthebrazemetal andtheparentmaterial Page13 ENISO18279:2003INES:97281O3002(E) 41 Table1Classificationofimperfections (continued) Desi
38、gnation Description Remarks Drawing 4JAAA fillingimperfection Incompletefillingofthegap 4JAAA 4CAAA incompletepenetration Thebrazemetalhasfailedtoflowthroughtherequired lengthofthejoint l t l r l Thearrowindicatesthedirectionofflowthroughthe joint. Page14 ENISO18279:2003INES:97281O3002(E) 51 Table1C
39、lassificationofimperfections (continued) Designation Description Remarks Drawing VShapeandsizeimperfections 6BAAA excessbrazemetal Brazemetalhasspilledoverontoparentmaterialsolidifying asabeadorathicklayer 6BAAA 5AAAA imperfectshape Departurefromtheprescribedshapeofthebrazedjoint 5EIAA linearmisalig
40、nment (linearoffset) Thecomponentsareparallelbutoffset 5EJAA angularmisalignment Thecomponentsformanangledeviatingfromtherequired value. 5BAAA distortion Unwantedchangeintheshapeofthebrazedassembly Page15 ENISO18279:2003INES:97281O3002(E) 61 Table1Classificationofimperfections (continued) Designatio
41、n Description Remarks Drawing 5FABA localizedmelting(or meltthrough) Throughgoingholeinthebrazedjointornexttoit 5FABA 7NABD fusedparentmaterial surface Fusedsurfaceofthebrazedassemblyintheregionofthe joint 7OABP erosionbyfillermetal Erosivedamagetothesurfaceofthebrazedassembly. 6GAAA recessedbrazeme
42、tal (recessedfillet) Thesurfaceofthebrazemetalinthebrazedjointisbelow therequireddimension Thesurfaceofthebrazemetalhassunkbelowthesurfaceof theparentmaterial 6GAAA 6GAAA Page16 ENISO18279:2003INES:97281O3002(E) 71 Table1Classificationofimperfections (continued) Designation Description Remarks Drawi
43、ng 5HAAA roughsurface Irregularsolidification,liquation,etc. 6FAAA insufficientfillet Filletbelowspecifiedsizehasformed 5GAAA irregularfillet Appearanceoffilletvariable VIMiscellaneousimperfections 7AAAA miscellaneous imperfection ImperfectionthatcannotbeclassifiedintogroupsItoVof thistable. Page17
44、ENISO18279:2003INES:97281O3002(E) 81 Table1Classificationofimperfections (continued) Designation Description Remarks Drawing 4VAAA fluxseepage Emergenceoffluxresiduesatsurfacepores 4VAAA 7CAAA spatter Dropsofbrazemetaladheringtothesurfaceofthebrazed assembly. 7SAAA discoloration/oxidation Oxidation/fluxaction/depositionofvolatizedfiller
