1、| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BRITISH STANDARD BS EN ISO 4042:2000 The E
2、uropean Standard EN ISO 4042:1999 has the status of a British Standard ICS 21.060.01; 25.220.40 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Fasteners Electoplated coatingsThis British Standard, having been prepared under the direction of the Engineering Sector Committee, w
3、as published under the authority of the Standards Committee and comes into effect on 15 May 2000 BSI 05-2000 ISBN 0 580 34867 9 BS EN ISO 4042:2000 Amendments issued since publication Amd. No. Date Comments National foreword This British Standard is the official English language version of EN ISO 40
4、42:1999. It is identical with ISO 4042:1999. The UK participation in its preparation was entrusted by Technical Committee FME/9, Bolts, nuts and accessories, to Subcommittee FME/9/1, Mechanical properties of fasteners, which has the responsibility to: aid enquirers to understand the text; present to
5、 the responsible European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. A list of organizations represented on this subcommittee can be obtained on req
6、uest to its secretary. Cross-references Attention is drawn to the fact that CEN and CENELEC Standards normally include an annex which lists normative references to international publications with their corresponding European publications. The British Standards which implement international or Europe
7、an publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necess
8、ary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, the EN ISO title page,
9、the EN ISO foreword page, the ISO title page, pages ii and iii, a blank page, pages 1 to 23, the annex ZA page, an inside back cover and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued.A Referencenumbe r ISO4042:1999 (E) INTERNATIONAL STA
10、NDARD ISO 4042 Secondedition 19990615 FastenersElectroplatedcoatings lmentsdefixationRevtementslectrolytiquesISO4042:1999(E) ii Contents Page 1Scop e1 2Normativereference s1 3Termsanddefinition s.2 4Dimensionalrequirementsandgaugin g.3 4.1Dimensionalrequirementsbeforeelectroplatin g3 4.2Dimensionalr
11、equirementsafterelectroplatin g.3 5Othercoatingrequirement s3 6Hydrogenembrittlementrelie f3 7Corrosionprotectio n.4 8Applicabilitytofastenersthatcutorformtheirownmatingthread s4 9Specificationofcoatingthicknes s.4 10Measurementofcoatingthicknes s5 10.1Localthicknes s.5 10.2Batchaveragethicknes s7 1
12、0.3Agreementontestmetho d7 11Samplingforthicknesstest s7 12Orderingrequirementsforelectroplatin g.7 13Designatio n7 AnnexA (informative) Hydrogenembrittlementrelie f.8 AnnexB (informative) Saltspraycorrosionprotectionperformanceofmetalliccoating s.10 AnnexC (informative) Guidanceonproceduresthatmayb
13、eadoptedtoaccommodatethickcoating s.12 AnnexD (normative) Determinationofbatchaveragethicknes s13 AnnexE (normative) Designationcode,systemA,forelectroplatedcoatingsonthreadedparts .16 AnnexF (informative) Examplesforcoatingdesignatio n.19 AnnexG (informative) Surfaceareasofbolts,screwsandnut s20 Bi
14、bliography23 ISO4042:1999(E) iii Foreword ISO (the InternationalOrganizationforStandardization)isaworldwidefederationofnationalstandardsbodies(ISO memberbodies).TheworkofpreparingInternationalStandardsisnormallycarriedoutthroughISOtechnical committees.Eachmemberbodyinterestedinasubjectforwhichatechn
15、icalcommitteehasbeenestablishedhas therighttoberepresentedonthatcommittee.Internationalorganizations,governmentalandnongovernmental,in liaisonwithISO,alsotakepartinthework.ISOcollaboratescloselywiththeInternationalElectrotechnical Commission(IEC)onallmattersofelectrotechnicalstandardization. Interna
16、tionalStandardsaredraftedinaccordancewiththerulesgivenintheISO/IECDirectives,Part3. DraftInternationalStandardsadoptedbythetechnicalcommitteesarecirculatedtoth ememberbodiesforvoting. PublicationasanInternationalStandardrequiresapprovalbyatleast75%ofthememberbodiescastingavote. International Standar
17、d ISO 4042 waspreparedbyTechnicalCommitteeISO/TC2, Fasteners,SubcommitteeSC1, Mechanicalpropertiesoffasteners . Thissecondeditioncancelsandreplacesthefirstedition(ISO4042:1989)whichhasbeentechnicallyrevised. AnnexesDandEformanormativepartofthisInternationalStandard.AnnexesA,B,C,FandGareforinformatio
18、n only.INTERNATIONALSTANDARD ISO4042:1999(E) 1 FastenersElectroplatedcoatings 1Scope This International Standard specifiesdimensionalrequirementsforelectroplatedfastenersofsteelorcopperalloy.It specifiescoatingthicknessesandgivesrecommendationsforhydrogenembrittlementreliefforfastenerswithhigh tensi
19、lestrengthorhardnessandforsurfacehardenedfasteners. This International Standard primarily concerns the electroplatingofthreadedfasteners,butitmayalsobeappliedto otherthreadedparts.Fortheapplicabilitytoscrewsthatcutorformtheirownmatingthreads,seeclause8. The specifications given in this International
20、 Standardmayalsobeappliedtononthreadedpartssuchaswashers andpins. 2Normativereferences The followingnormativedocumentscontainprovisionswhich,throughreferenceinthistext,constituteprovisionsof thisInternationalStandard.Fordatedreferences,subsequentamendmentsto,orrevisions of,anyofthese publications do
21、 not apply. However,partiestoagreementsbasedonthisInternationalStandardareencouragedto investigatethepossibilityofapplyingthemostrecenteditionso fthenormativedocumentsindicatedbelow.For undatedreferences,thelatesteditionofthenormativedocumentreferredtoapplies.MembersofISOandIEC maintainregistersofcu
22、rrentlyvalidInternationalStandards. ISO9651:1999, ISOgeneralpurposemetricscrewthreadsTolerancesPart1:Principlesandbasicdata. ISO9652:1999, ISOgeneralpurposemetricscrewthreadsTolerancesPart2:Limitsofsizesforgeneral purposeboltandnutthreadsMediumquality . ISO9653:1999, ISOgeneralpurposemetricscrewthre
23、adsTolerancesPart3:Deviationsforconstructional threads. ISO1456:1988, MetalliccoatingsElectrodepositedcoatingsofnickelpluschromiumandofcopperplusnickel pluschromium. ISO1458:1988, MetalliccoatingElectrodepositedcoatingsofnickel . ISO1502:1996, ISOgeneralpurposemetricscrewthreadsGaugesandgauging . IS
24、O2064:1996,Metallicandothernonorganiccoatings Definitionsandconventionsconcerningthe measurementofthickness . ISO2081:1986, MetalliccoatingsElectroplatedcoatingsofzinconironorsteel . ISO2082:1986, MetalliccoatingsElectroplatedcoatingsofcadmiumonironorsteel .ISO4042:1999(E) 2 ISO3269: 1) , FastenersA
25、cceptanceinspection . ISO4520:1981, Chromateconversioncoatingsonelectroplatedzincandcadmiumcoatings . ISO9227:1990, CorrosiontestsinartificialatmospheresSaltspraytests . ISO9587: 2) ,MetallicandotherinorganiccoatingsPretreatmentsofironorsteelforreducingtheriskof hydrogenembrittlement . ISO15330: 2)
26、,Fasteners Preloadingtestforthedetectionofhydrogenembrittlement Parallelbearing surfacemethod. 3Termsanddefinitions ForthepurposesofthisInternationalStandard,thedefinitionsgiveninISO2064(inparticular,thedefinitionsof significantsurface,measuringarea,localthicknessandminimumlocalthickness)an dISO3269
27、togetherwiththe following,apply. 3.1 batch quantityofidenticalfastenersfromthesamemanufacturinglotprocessedtogetheratonetime 3.2 productionrun thosebatchesofpartsprocessedcontinuouslywithoutanychangesincoatingtechniquesorconstituents 3.3 batchaveragethickness calculatedaveragethicknessofacoatingifit
28、wasuniformlydistributedoverthesurfaceofthepartsofthebatch 3.4 baking processofheatingpartsforadefinitetimeatagiventemperatureinordertominimizetheriskofhydrogen embrittlement 3.5 bakingduration timeatwhichthepartsareheldatthespecifiedtemperaturewhichtheyshallhavecompletelyreached 1) Tobepublished.(Re
29、visionofISO3269:1988) 2) Tobepublished.ISO4042:1999(E) 3 4Dimensionalrequirementsandgauging 4.1Dimensionalrequirementsbeforeelectroplating Beforecoating,partsshallcomplywiththerelevantInternationalStandardsifapplicableorotherstandardsas specified, except where threads or other featuresarespecificall
30、ymanufacturedtoallow,forfunctionalreasons,the applicationofthickercoatingsthanarepossibleonnormalthreads. CoatingthicknesseswhichcanbeappliedonISOmetricthreadsinaccordancewithISO9651 , ISO 965 2 and ISO 9653dependonthefundamentaldeviationavailable,whichitselfdependsonthescrewthreadandthefollowing to
31、lerancepositions: g,f,eforexternalthreads; GforinternalthreadsorHifrequired. Thetolerancepositionsapplypriortoapplicationoftheelectroplatedcoating. 4.2Dimensionalrequirementsafterelectroplating Aftercoating,ISOmetricscrewthreadsshallbegaugedinaccordancewithISO 1502withaGOgaugeoftolerance positionhfo
32、rexternalthreadsandHforinternalthreads. Otherproductdimensionsapplyonlybeforecoating. NOTE Care should be exercised whererelativelythickcoatings mayaffectdi mensionswiths malltolerancesasinthecase ofinternaldrives;inthesecasesanagreementshouldbemadebetweenthesupplierandthepurchaser. The applicabilit
33、y oftherecommendedcoatingstoISOmetricthreadsislimitedbythefundamentaldeviationofthe threadsconcernedandhence,bythepitchandtolerancepositions.Thecoatingshallnotcausethezeroline(basic size)tobeexceededinthecaseofexternalthreads,norshallitfallbelowthislineinthecaseofinternalthreads. Thismeansthatforani
34、nternalthreadoftolerancepositio n H,ameasurablecoatingthicknesscanonlybeapplied tothethreadsifthetolerancezoneisnottakenuptothezeroline(basicsize). 5Othercoatingrequirements TheelectroplatedcoatingshallcomplywiththeprovisionsoftherelevantInternationa lStandards(ISO1456, ISO 1458,ISO 2081,ISO 2082)fo
35、rthecoatingconcernedinrespec tofappearance,adhesion,ductility,corrosion resistance,etc. 6Hydrogenembrittlementrelief Incasesofparts withhightensilestrengthorhardnessorwhichhavebeensurfacehardened, whichhaveabsorbedhydrogenand areundertensilestress thereistheriskoffailureduetohydrogenembrittlement. W
36、henthecoreorsurfacehardnessisabove320HV,processinvestigationshallbeconductedusingatest to detect hydrogenembrittlement,forexamplethe“Parallelbearingsurfacemethod“inaccordancewit hISO 15330,tobe surethattheprocesswithregardtoembrittlementisunder control.Ifembrittlementisdiscovered,modificationof them
37、anufacturingprocesswillbenecessary,suchastheinclusionofabakingprocess(seeinformativeannex A for moreinformation).ISO4042:1999(E) 4 Forfastenersofhardnessinexcessof365HV,awrittenagreementshouldexistbetweenthecustomerand manufacturer to define how to manage therisk.Ifwrittenagreementdoesnotexist,thema
38、nufacturershallprocessthe partsinaccordancewithhisrecommendedpracticestoreducetheriskofhydrogenembrittlement. Complete elimination of hydrogen embrittlement cannot beassured.Ifareducedprobabilityofencountering hydrogenembrittlementisdesired,alternativeproceduresshouldbeevaluated. NOTE Investigations
39、areproceedingtodevelopmethodsforthereductionofhydrogenembrittlement. 7Corrosionprotection The corrosion protection of an electroplated coating dependstoaconsiderableextentonitsthickness.Inadditionto greatercoatingthickness,achromateconversiontreatmentcanbespecifiedforincreasedcorrosionprotectionon z
40、incandcadmiumcoatings. Contactwithothermetalsandmaterials,thefrequencyanddurationofwettingandservicetemperaturesmay influencetheprotectiveperformanceofcoatingsandexpertadviceisessentialwhenuncertaintiesofchoicearise. CoatingsofZnandCdappliedtoferroussubstratesarelesselectropositivethanth esteelbasem
41、etaland consequentlyprovidecathodicprotection.Incontrast,NiandCrcoatingsaremoreelectropositivethanthesteel basemetalandmayintensifypartcorrosionwherethecoatingisdamagedorpitted. Cadmium coatingsaredealtwithinISO2082. ZinccoatingsaredealtwithinISO2081. NickelcoatingsaredealtwithinISO1458. Nickel 1chr
42、o miumandcopper 1nic kel 1chro mium coatingsaredealtwithinISO1456. Chromateconversiontreat mentsaredealtwithinISO4520. NOTE InformationonsaltspraycorrosionprotectionperformanceofmetalliccoatingsisgivenininformativeannexB. 8Applicabilitytofastenersthatcutorformtheirownmatingthreads Allrecommendedcoat
43、ingsmaybeappliedtoscrewsthatcutorformtheir ownmatingthreadssuchaswood screws, self tapping screws, selfdrillingscrewsandthreadformingscrews.Themaximumvalueforbatchaverage thicknessgiveninTable1maybeignoredunlessotherwisespecified. 9Specificationofcoatingthickness Thelocalandbatchaveragethicknessesco
44、rrespondingtoth enominalcoatingthicknessesrecommendedinthe relevantInternationalStandardsforelectroplatingaregiveninTable1. Inordertoreducetheriskofinterferenceonassemblyofthreadswithelectroplatedcoatings,th e coating thickness shallnotexceedonequarterofthefundamentaldeviationofthethread.ThesevaluesarespecifiedinTable2. NOTE Foraccommodationofthickcoatin
