ANSI ASME B1.30-2002 Screw Threads Standard Practice for Calculating and Rounding Dimensions《螺纹 尺寸计算和尺寸修约的标准实施规程》.pdf

1、ASME B1.30-2002(Revision of ASME B1.30M-1992)ASME B1.30-2002(Revision of ASME B1.30M-1992)SCREW THREADS:STANDARD PRACTICEFOR CALCULATINGAND ROUNDINGDIMENSIONSSCREW THREADS:STANDARD PRACTICEFOR CALCULATINGAND ROUNDINGDIMENSIONSAN AMERICAN NATIONAL STANDARDREAFFIRMED 2017Intentionally left blank AN AM

2、ERICAN NATIONAL STANDARDSCREW THREADS:STANDARD PRACTICEFOR CALCULATINGAND ROUNDINGDIMENSIONSASME B1.30-2002Revision of ASME B1.30M-1992Date of Issuance: April 25, 2003This Standard will be revised when the Society approves the issuance of a new edition. There willbe no addenda or written interpretat

3、ions of the requirements of this Standard issued to this edition.ASME is the registered trademark of The American Society of Mechanical Engineers.This code or standard was developed under procedures accredited as meeting the criteria for American NationalStandards. The Standards Committee that appro

4、ved the code or standard was balanced to assure that individuals fromcompetent and concerned interests have had an opportunity to participate. The proposed code or standard was madeavailableforpublicreviewandcommentthatprovidesanopportunityforadditionalpublicinputfromindustry,academia,regulatory age

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7、tirely their own responsibility.Participation by federal agency representative(s) or person(s) affiliated with industry is not to be interpreted asgovernment or industry endorsement of this code or standard.ASME accepts responsibility for only those interpretations of this document issued in accorda

8、nce with the establishedASME procedures and policies, which precludes the issuance of interpretations by individuals.No part of this document may be reproduced in any form,in an electronic retrieval system or otherwise,without the prior written permission of the publisher.The American Society of Mec

9、hanical EngineersThree Park Avenue, New York, NY 10016-5990Copyright 2003 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll rights reservedPrinted in U.S.A.CONTENTSForeword ivCommitteeRoster v1 General . 12 Rounding of Decimal Values 13 Calculations From Formulas 24 Thread Form Constants . 2Tables1

10、NumberofDecimalPlacesUsedinCalculations 22 ExampleofExternalInchScrewThreads,12-28UNEF-2A. 43 ExampleofInternalInchScrewThreads,12-28UNEF-2B 74 ExampleofExternalInchScrewThreads,1964-36UNS-2A. 95 ExampleofInternalInchScrewThreads,1964-36UNS-2B 126 ExampleofExternalMetricScrewThreads,M12H115471.75-4g

11、6g . 147 ExampleofInternalMetricScrewThreads,M12H115471.75-6H 168 ExampleofExternalMetricScrewThreads,M13H115470.9-4g6g 189 ExampleofInternalMetricScrewThreads,M13H115470.9-6H. 2010 ThreadFormData. 22Nonmandatory AppendixA ThreadCharacteristicsGovernedbythisStandard 23iiiFOREWORDTheAmericanNationalS

12、tandardsCommitteeB1forstandardizationofscrewthreadswasorganizedin1920assectionalCommitteeB1underthesponsorshipoftheAmericanEngineeringStandardsCommittee(latertheAmericanStandardsAssociation,thentheUnitedStatesofAmericaStandardsInstituteandasofOctober6,1969,theAmericanNationalStandardsInstitute,Inc.)

13、,withtheSocietyofAutomotiveEngineersandTheAmericanSocietyofMechanicalEngineersas joint sponsors. As a result, a great deal of effort was expended through the years towarddevelopmentofseveralscrewthreadstandards.Recognizingtheneedtostandardizethemethodofroundingdecimalvaluesinthecalculationofscrewthr

14、eaddimemsions,theASMEStandardsCommitteeB1chargedSubcommittee30withtheresponsibilityforproducingsuchastandard.ThisStandarddesignatedASMEB1.30wasdevelopedonlytoserveasthebasisforroundingofdecimalvaluesassociatedwiththecomputationofscrewthreaddimensions.The examples and formulas depicted within this St

15、andard are for reference only and arepresentedonlytoclarifytheroundingproceduresdescribed.Whencalculatingthedifferentthreadcharacteristicsforaparticularthreadform,refertotheappropriateASMEB1standardfortheformulasandmethodologyofcalculationforthatthread.ThisStandardwasoriginallyapprovedasanAmericanNa

16、tionalStandardonJune29,1992.Thisissueupdatesthe1992issueandincludes:(a) theadditionofanotetopara.1.2fortheclarificationoftheuseofthisStandardformetricapplications;(b) theadditionofanexceptioninpara.3.1.3tothenumberofdecimalplacesfortheallowance2AwhenusedinintermediatecalculationsasTd2;(c) theadditio

17、nofthemaximumexternalUNminordiameter,maximumandminimuminternalpitchdiametersandtheminimuminternalmajordiametertotheexampleinpara.3.2.1;(d) removal of Appendix A containing various common values for 60 deg thread elements.This was done because the values are either listed or can be calculated by form

18、ulas in otherexistingB1standards;(e) theadditionofanexampleforastandardmetricsizethatislistedinASMEB1.13MandISO261;(f) theadditionofanexampleforaspecialinchsizeshowinghowtoroundnumberswithaninfinitenumberofdigitsafterthedecimalpoint;(g) added a new Appendix A with a table listing the number of decim

19、al places for each ofthethreadcharacteristicsusedintheexamplesinB1.30.SuggestionsforimprovementofthisStandardwillbewelcome.TheyshouldbesenttoSecretary,ASMEB1StandardsCommittee,ThreeParkAvenue,NewYork,NY10016-5990U.S.A.ThisrevisionwasapprovedasanAmericanNationalStandardonJuly12,2002.ivASME STANDARDS

20、COMMITTEE B1Standardization and Unification of Screw Threads(The following is the roster of the Committee at the time of approval of this Standard.)OFFICERSA. L. Barrows, ChairD. S. George, Vice ChairJ. R. Bird, SecretaryCOMMITTEE PERSONNELG. L. Allen, The L. S. Starrett Co.A. L. Barrows, Kennametal

21、-IPGM. H. Bernier, Standard Nut and BoltJ. R. Bird, The American Society of Mechanical EngineersF. G. Calderone, Quality Systems ImplementersJ. Davis, U.S. Nuclear Regulatory CommissionL. N. Dixon, Jr., General ElectricR. Dodge, Pennoyer-Dodge Co.G. A. Flannery, Mercury Gage Co.D. Skierski, Alternat

22、e, Mercury Gage Co.H. N. Frost, Defense Supply Center PhiladelphiaD. S. George, Ford Motor Co.J. R. Gervasi, Kerr Lakeside Inc.J. Greenslade, Greenslade EXAMPLE:1.01235 1.01241.0123500 1.01241.012345 1.012351.01234500 1.01235(b) ifthe5nextbeyondthefigureinthelastplacetoberetainedarefollowedbyanyfigu

23、resotherthanzero,ASME B1.30-2002 SCREW THREADS: STANDARD PRACTICE FORCALCULATING AND ROUNDING DIMENSIONSTable 1Number of Decimal Places Used in CalculationsUnits Pitch Constants Intermediate FinalInch 8 8 6 4 (except as outlined in para. 3.1.3)Metric as designated 7 5 3thefigureinthelastplaceretaine

24、dshouldbeincreasedby1.EXAMPLE:1.0123501 1.01241.0123599 1.01241.01234501 1.012351.01234599 1.012352.1.4 Thefinalroundedvalueisobtainedfromthemost precise value available and not from a series ofsuccessiverounding.Forexample,0.5499shouldberoundedto0.550,0.55and0.5(not0.6),sincethemostprecisevalueavai

25、lableislessthan0.55.Similarly,0.5501shouldberoundedas0.550,0.55and0.6,sincethemostprecisevalueavailableismorethan0.55.Inthecaseof0.5500roundingshouldbe0.550,0.55and0.6,sincethemostprecisevalueavailableis0.5500.3 CALCULATIONS FROM FORMULAS3.1 General Rules3.1.1 Valuesforpitchandconstantsderivedfromaf

26、unction of pitch are used out to eight decimal placesforinchseries.Theeightplacevaluesareobtainedbyroundingtheirtruncatedtenplacevalues.Sevendecimalplacevaluesformetricseriesconstantsarederivedbyroundingtheirtruncatednineplacevalues.Seepara.4forthreadformconstants.Valuesusedinintermediatecalculation

27、sareroundedtotwoplacesbeyondthenum-ber of decimal places retained for the final value, seeTable1.EXAMPLE:np28threadsperinchPp1/nPp1/28Pp0.0357142857Pp0.035714293.1.2 Roundingtothefinalvalueisthelaststepinacalculation.3.1.3 Forinchscrewthreaddimensions,fourdecimalplacesarerequiredforthefinalvaluesofp

28、itchdiameter,majordiameter,andminordiameterwiththeexceptionofClass1Band2Binternalthreadminordiametersforthreadsizes0.138andlarger,seebelow.Thefinalvaluesfortheallowancesandtolerancesappliedtothreadele-ments are expressed to four decimal places except for2externalthreadpitchdiametertolerance,Td2,whic

29、hisexpressedtosixdecimalplaces.(a) MinorDiameterExceptionsforInternalThreads:(1) MinimumMinorDiameter.Allclassesarecalcu-latedandthenroundedofftothenearest0.001in.andexpressedinthreedecimalplacesforsizes0.138in.andlarger.ForClass3B,azeroisaddedtoyieldfourdecimalplaces.(2) MaximumMinorDiameter.Allcla

30、ssesarecalcu-latedbeforerounding,thenroundedforClasses1Band2Btothenearest0.001in.forsizes0.138in.andlarger.Class3Bvaluesareroundedtofourdecimalplaces.3.1.4 Metricscrewthreadsaredimensionedinmilli-meters.Thefinalvaluesofpitchdiameter,majordiame-ter,minordiameter,allowanceandthreadelementtolerancesare

31、expressedtothreedecimalplaces.3.1.5 Values containing multiple trailing zeros outto the required number of decimal places can beexpressedbydisplayingonlytwoofthembeyondthelastsignificantdigit.EXAMPLE: 20 threads per inch has a pitch equal to 0.05000000andcanbeexpressedas0.0500.3.2 ExamplesTheformula

32、sintheexamplesforinchscrewthreadsinTables2,3,4and5arebasedonthoselistedinASMEB1.1, Unified Inch Screw Threads. Tables 2 and 3 arebasedonasizethatwhenconvertedfromafractiontoa decimal will result in a number that has only fourdecimalplaces.Tables4and5arebasedonasizethatwhen converted will result in a

33、 number with infinitenumbersofdigitsafterthedecimalpoint.TheformulasintheexamplesformetricscrewthreadsinTables6,7,8and9arebasedonthoselistedinASMEB1.13M,MetricScrewThreads.Tables6and7showtheuseofthetabulatedvaluesforallowancesandtolerances(inaccordancewithISO965-1)forthecalculationofsizelimitsforsta

34、ndarddiameter/pitchcombinationslistedinbothISO261andASMEB1.13M.Theconstantvaluesdifferfromthoseusedforinchscrewthreads,inaccor-dancewiththepolicyofroundingofthisStandard,becausemetriclimitsofsizeareexpressedtoonlythreedecimalplacesratherthanfour.4 THREAD FORM CONSTANTSForthreadformdatatables,seeTabl

35、e10.Thenumberof decimal places and the manner in which they areSCREW THREADS: STANDARD PRACTICE FOR ASME B1.30-2002CALCULATING AND ROUNDING DIMENSIONSlistedshouldbeconsistent.Threadformconstantsprintedinolderthreadstandardsarebasedonafunctionofthreadheight(H)orpitch(P).Theequivalentofthecorrespondin

36、g function is also listed. There are someconstantsthatwouldrequirethesevaluesto8or7deci-malplacesbeforetheywouldroundtoequivalentval-ues.Forstandardizationthetabulatedlistingofthread3valuesbasedonafunctionofpitchhasbeenestablished,withthreadheightusedasareferenceonly.Allthreadcalculations are to be

37、performed using a function ofpitch (P), rounded to 8 decimal places for inch seriesand as designated for metric series, not a function ofthreadheight(H).Threadheightistobeusedforrefer-enceonly.ASME B1.30-2002 SCREW THREADS: STANDARD PRACTICE FORCALCULATING AND ROUNDING DIMENSIONSTable2ExampleofExter

38、nalInchScrewThreads,12-28UNEF-2AThreadSizep12-28or0.5000-28UNEF-2ACharacteristicDescriptionExampleofSizeCalculationAdditionalInformation(1)Maximumexternalmajordiameter(dmax.)dmax.pdbsces.pBasicmajordiameter(dbsc)allowance(es)dbscp0.5000Thisisthefinalvalueofthebasicmajordiameterwhichisroundedtofourde

39、cimalplaces.esp0.300(Td2forclass2A)FortheClass2Apitchdiametertolerance,seeTable2(4).esp0.300(0.003668)ThesixdecimalplacevalueforClass2Apitchdiametertolerance(Td2)isusedinthiscalculation.esp0.001100Thisfigureisroundedtofourdecimalplacestoobtainthefinalvalueofes.esp0.0011.dmax.p0.50000.0011.dmax.p0.49

40、89.(2)Minimumexternalmajordiameter(dmin.)dmin.pdmax.Td.pMaximumexternalmajordiameter(dmax.)majordiametertolerance(Td)Tdp0.0603H20906P2.Tdp0.0603H20906(0.03571429)2Allthreadcalculationsaretobeperformedusing(P)roundedto8decimalplaces.Tdp0.0603H209060.001276).Tdp0.060(0.108463).Tdp0.006508Thisfigureisr

41、oundedtofourdecimalplacestoobtainthefinalvalueofTd.Tdp0.0065.dmin.p0.49890.0065.dmin.p0.4924.4SCREW THREADS: STANDARD PRACTICE FOR ASME B1.30-2002CALCULATING AND ROUNDING DIMENSIONSTable2ExampleofExternalInchScrewThreads,12-28UNEF-2A(Contd)ThreadSizep12-28or0.5000-28UNEF-2ACharacteristicDescriptionE

42、xampleofSizeCalculationAdditionalInformation(3)Maximumexternalpitchdiameter(d2max.)d2max.pdmax.2has.pMaximumexternalmajordiameter(dmax.)twicethe2hasp0.64951905P.externalthreadaddendum(2has)2hasp0.64951905(0.03571429)Allthreadcalculationsaretobeperformedusing(P)roundedto8decimalplaces.2hasp0.023197.d

43、2max.p0.49890.023197.d2max.p0.475703Thisfigureisroundedtofourdecimalplacestoobtainthefinalvalueofd2max.d2max.p0.4757.(4)Minimumexternalpitchdiameter(d2min.)d2min.pd2max.Td2.pMaximumexternalpitchdiameter(d2max.)externalpitchdiametertolerance(Td2)Td2p0.00153H20906dbsc+0.0015H20906LE+0.0153H20906P2LE(l

44、engthofengagement)requiredinthisexample,isequalto9P.SeeASMEB1.1forLEapplicationsforotherthreadseries.Td2p0.00153H209060.5000+0.0015H209069(0.03571429)+0.0153H20906(0.03571429)2.Td2p0.00153H209060.5000+0.0015H209060.321429+0.0153H209060.001276.Td2p(0.0015)(0.793701)+(0.0015)(0.566947)+(0.015)(0.10846

45、3).Td2p0.001191+0.000850+0.001627.Td2p0.003668ThisfigureisroundedtosixdecimalplacestoobtainthefinalvalueoftheexternalpitchdiametertoleranceTd2.d2min.p0.47570.003668.d2min.p0.472032Thisfigureisroundedtofourdecimalplacestoobtainthefinalvalueofd2min.d2min.p0.4720.5ASME B1.30-2002 SCREW THREADS: STANDAR

46、D PRACTICE FORCALCULATING AND ROUNDING DIMENSIONSTable2ExampleofExternalInchScrewThreads,12-28UNEF-2A(Contd)ThreadSizep12-28or0.5000-28UNEF-2ACharacteristicDescriptionExampleofSizeCalculationAdditionalInformation(5)MaximumexternalUNRminordiameter(d3max.)d3max.pdmax.2hs.pMaximumexternalmajordiameter(

47、dmax.)doubleheight2hsp1.19078493P.ofexternalUNRthread(2hs)2hsp1.19078493(0.03571429)Allthreadcalculationsaretobeperformedusing(P)roundedto8decimalplaces.2hsp0.042528.d3max.p0.49890.042528.d3max.p0.456372Thisfigureisroundedtofourdecimalplacestoobtainthefinalvalueofd3max.d3max.p0.4564.(6)Maximumextern

48、alUNminordiameter(d1max.)d1max.pdmax.2hs.pMaximumexternalmajordiameter(dmax.)doubleheight2hsp1.08253175PForUNthreads,2hsp2hnofexternalUNthread(2hs)2hsp1.08253175(0.03571429)Allthreadcalculationsaretobeperformedusing(P)roundedto8decimalplaces.2hsp0.038662.d1max.p0.49890.038662.d1max.p0.460238Thisfigu

49、reisroundedtofourdecimalplacestoobtainthefinalvalueofd1max.d1max.p0.4602.GENERALNOTES:(a)Alldimensionsexpressedininchesforcalculationsinthistable.(b)Pp1/np1/28p0.03571429.6SCREW THREADS: STANDARD PRACTICE FOR ASME B1.30-2002CALCULATING AND ROUNDING DIMENSIONSTable3ExampleofInternalInchScrewThreads,12-28UNEF-2BThreadSizep12-28or0.5000-28UNEF-2BCharacteristicDescriptionExampleofSizeCalculationAdditionalInformation(1)Minimuminternalminordiameter(D1min.)D1min.pDbsc2hn.pBasicmajordiameter(Dbsc)doubleheightofinternal2hnp1.08253175P.thread(2hn)2hnp1.08253175(0.0357