欢迎来到人人文库网! | 帮助中心 人人文库renrendoc.com美如初恋!
人人文库网
首页 人人文库网 > 资源分类 > DOC文档下载

外文翻译---尺寸控制.doc

  • 资源大小:57.50KB        全文页数:9页
  • 资源格式: DOC        下载权限:游客/注册会员/VIP会员    下载费用:5
游客快捷下载 游客一键下载
会员登录下载
下载资源需要5

邮箱/手机号:
您支付成功后,系统会自动为您创建此邮箱/手机号的账号,密码跟您输入的邮箱/手机号一致,以方便您下次登录下载和查看订单。注:支付完成后需要自己下载文件,并不会自动发送文件哦!

支付方式: 微信支付    支付宝   
验证码:   换一换

友情提示
2、本站资源不支持迅雷下载,请使用浏览器直接下载(不支持QQ浏览器)
3、本站资源下载后的文档和图纸-无水印,预览文档经过压缩,下载后原文更清晰   

外文翻译---尺寸控制.doc

附录附录1英文翻译DIMENSIONALCONTROLINTHEEARLYDAYSOFENGINEER,THEMATINGOFPARTSWASACHIEVEDBYMACHININGONEPARTASNEARLYASPOSSIBLETOTHEREQUIREDSIZE,MACHININGTHEMATINGPARTNEARLYTOSIZE,ANDTHENCOMPLETINGITSMACHINING,CONTINUALLYOFFERINGTHEOTHERPARTTOIT,UNTILTHEDESIREDRELATIONSHIPWASOBTAINEDIFITWASINCONVENIENTTOOFFERONEPARTTOTHEOTHERPARTDURINGMACHINING,THEFINALWORKWASDONEATTHEBENCHBYAFITTER,WHOSCRAPEDTHEMATINGPARTSUNTILTHEDESIREDFITWASOBTAINED,THEFITTERTHEREFOREBEINGA‘FITTER’INTHELITERALSENSEITISOBVIOUSTHATTHETWOPARTSWOULDHAVETOBEDONEALLOVERAGAININTHESEDAYS,WEEXPECTTOBEABLETOPURCHASEAREPLACEMENTFORABROKENPART,ANDFORITTOFUNCTIONCORRECTLYWITHOUTTHENEEDFORSCRAPINGANDOTHERFITTINGOPERATIONSWHENONEPARTCANBEUSED‘OFFTHESHELF’TOREPLACEANOTHEROFTHESAMEDIMENSIONANDMATERIALSPECIFICATION,THEPARTSARESAIDTOBETOBEINTERCHANGEABLEASYSTEMOFINTERCHANGEABILITYUSUALLYLOWERSTHEPRODUCTIONCOSTS,ASTHEREISNONEEDFORANEXPENSIVE‘FIDDLING’OPERATION,ANDITALSOBENEFITSTHECUSTOMERINTHEEVENTOFTHENEEDTOREPLACEWORNPARTSITALSO,HOWEVER,DEMANDSTHATTHEDIMENSIONOFMATINGPARTSBESPECIFIED,ANDTHATDIMENSIONALVARIATIONS,DUETOMACHINEANDOPERATORSHORTCOMINGS,BETAKENINTOACCOUNTSOMEFORMOFINSPECTIONMUSTBEINTRODUCEDTOENSURETHATTHEMANUFACTUREISCONTROLLED;THISISPARTICULARLYIMPORTANT,BECAUSEDIMENSIONALERRORSMAYNOTBEREVEALEDUNTILSOMETIMEHASELAPSED,ANDOFTENMANYMILESFROMTHEPLACEWHERETHEMACHININGWASDONE1TOLERANCEANDLIMITSOFSIZESINCEITISACCEPTEDTHATITISVIRTUALLYIMPOSSIBLETOMANUFACTUREAPARTWITHOUTERROR,ORINTHERAREEVENTOFAPARTBEINGWITHOUTERROR,TOBEABLETOPROCLAIMITTOBEPERFECTBECAUSETHEMEASURINGINSTRUMENTSARESUBJECTTOERRORS,ITISNECESSARYTOINDICATETHEMAXIMUMERRORSPERMITTEDTHEDRAUGHTSMANMUSTINDICATETHELARGESTANDSMALLESTSIZESTHATTHELIMITSOFSIZE,ANDTHEDIFFERENCEBETWEENTHEMISCALLEDTHETOLERANCE,THEACTUALTOLERANCEMUSTBEINCREASEDWITHSIZETHETOLERANCESHOULDBEASLARGEASPOSSIBLE,TOKEEPTHECOSTTOAMINIMUMTHEMETHODOFINDICATING,ONADRAWING,THEPERMITTEDTOLERANCEDEPENDSMAINLYUPONTHETYPEOFOPERATIONINVOLVED,BUTLOCALPREFERENCEMUSTALSOBETAKENINTOACCOUNTTHEFOLLOWINGEXAMPLESWILLILLUSTRATESOMEOFTHEMETHODSUSED,1UNILATERALLIMITSTHESEAREUSUALLYUSEDWHENTHEDISTANCEBETWEENTWOFACES,ORTHEDIAMETEROFAHOLEORSHAFTIDSPECIFIEDFOREXAMPLE,WHENADIAMETERISBEINGGROUND,THEMACHINISTWOULDPREFERTOAIMATTHELARGESTSIZEPERMITTED,SOTHAT,INTHEEVENTOFHISREACHINGADIAMETERTHATISJUSTALITTLELARGERTHANTHEMAXIMUMSIZEPERMITTED,HECANTAKEANOTHERCUT,KNOWINGTHATHECANUSEUPTHEWHOLEOFTHETOLERANCEBEFORETHEJOBISREJECTEDADRAUGHTSMANMIGHTDIMENSIONANOMINAL750012MMDIAMETERSHAFTASD75SIMILARLY,ANOMINAL75MMHOLEMIGHTDIMENSIONEDASD750012,THESAMEREASONINGAPPLIESASFORSHAFTS2BILATERALLIMITSTHESEAREUSUALLYAPPLIEDWHEN,FOREXAMPLE,THEPOSITIONOFAHOLEISSPECIFIEDTHEMACHINEOPERATORMAYPOSITIONHEHOLENEARERTHEDATUMORFURTHERFROMTHEDATUMTHANINTENDED,HEMUSTAIMBETWEENTHELIMITSOFPOSITION,SOTHATTHEMAXIMUMERRORCANBEMADEWITHOUTCAUSINGTHEPARTTOBEREJECTEDTHECENTERDISTANCEBETWEENTWOHOLESWOULDTHEREFOREBESPECIFIEDAS,FOREXAMPLE,100002MM2FITSARECONCERNEDWITHTHERELATIONSHIPBETWEENTWOPARTSCONSIDERASHAFTANDAHOLECOMBINATIONIFTHESHAFTISLARGERTHANTHEHOLE,THECONDITIONISSAIDTOBEOFINTERFERENCE;ANDIFSMALLERTHANTHEHOLE,THECONDITIONISSAIDTOBEOFCLEARANCETHEINTERFERENCEMAYBESUCHTHATTHETWOPARTSCANBEASSEMBLEDONLYBYSHRINKING,ORITMAYBEVERYSLIGHT,SOTHATTHEPARTSCANBEASSEMBLEDBYHANDOPERATEDPRESSSIMILARLY,THECLEARANCECANBESLIGHT,SOTHATTHESHAFTCANROTATEEASILYINTHEHOLE,ORBELARGE,SOTHATTHEREISAMPLECLEARANCEFORBOLTSTOPASSTHROUGHINORDERTHATTHEPRECISECONDITIONISENSURED,THELIMITSOFSIZEOFBOTHTHESHAFTANDTHEHOLEMUSTBESTIPULATED1CLASSESOFFITTHESEARECLASSIFIEDASFOLLOWSCLEARANCEFITWHENTHELIMITSOFSIZEOFBOTHTHEHOLEANDTHESHAFTARESUCHTHATTHESHAFTISALWAYSSMALLERTHANTHEHOLE,THEFITIDSAIDTOBEACLEARANCEFITINTERFERENCEFITWHENTHELIMITSOFSIZEOFBOTHTHEHOLEANDTHESHAFTARESUCHTHATTHESHAFTISALWAYSLARGERTHANTHEHOLE,THEFITIDSAIDTOBEAINTERFERENCEFITTRANSITIONFITWHENTHELIMITSOFSIZEOFBOTHTHEHOLEANDTHESHAFTARESUCHTHATTHECONDITIONMAYBECLEARANCEORINTERFERENCE,THEFITIDSAIDTOBEATRANSITIONFIT2HOLEBASEDSYSTEMANDSHAFTBASEDSYSTEMINORDERTOOBTAINARANGEOFDEGREESOFCLEARANCE,ANDDEGREESOFINTERFERENCE,ITISNECESSARYTOUSEAWIDEVARIATIONOFHOLESIZESANDSHAFTSIZESFOREXAMPLE,AMANUFACTURINGCOMPANYCOULDBEMAKINGANUMBEROFPARTS,ALLOFANOMINAL25MMDIAMETER,BUTWHICHAREALLSLIGHTLYDIFFERENTINACTUALLIMITSOFSIZE,TOSUITTHEACTUALFITREQUIREDOFEACHPAIROFPARTSTHISSITUATIONCOULDMEANTHATALARGENUMBEROFDRILLS,REAMERS,GAUGES,ETCWEREREQUIREDITISLOGICALTHAT,TOREDUCETHISNUMBER,ASTANDARDHOLECOULDBEUSEDFOREACHNOMINALSIZE,ANDTHEVARIATIONOFFITEOBTAINEDBYMAKINGTHEMATINGSHAFTSMALLERORLARGERTHANTHEHOLETHISISKNOWNASAHOLEBASEDSYSTEMALTERNATIVELY,ASTANDARDSHAFTCOULDBEUSEDFOREACHNOMINALSIZE,ANDTHEVARIATIONOFFITISOBTAINEDBYMAKINGTHEMATINGHOLELARGERORSMALLER,ASREQUIREDTHISISKNOWNASASHAFTBASEDSYSTEMAHOLEBASEDSYSTEMISUSUALLYPREFERRED,BECAUSEITSTANDARDIZES“FIXEDSIZE”EQUIPMENTSUCHASREAMERANDPLUGGAUGES;BUTASHAFTBASEDSYSTEMISUSUALLYALSOPROVIDED,BECAUSESOMETIMESITISMORECONVENIENTTOEMPLOYACOMMONSHAFTTOWHICHANUMBEROFCOMPONENTSISASSEMBLED,EACHWITHADIFFERENTFIT,ANDSOMETIMESITISCONVENIENTTOUSEBARSTOCKWITHOUTFURTHERMACHINING3SYSTEMSOFLIMITSANDFITSITISCONVENIENTTOESTABLISHASTANDARDIZEDSYSTEMOFLIMITSANDFITS,NOTONLYTOELIMINATETHENEEDFORTHEDRAUGHTSMANTODETERMINETHELIMITSEACHTIMEANASSEMBLYISDETAILED,BUTALSOTOSTANDARDIZETHETOOLSANDGAUGESREQUIREDASYSTEMOFLIMITSANDFITSSHOULDCATERFORAWIDERANGEOFNOMINALSIZESTOSATISFYTHEVARIOUSNEEDSOFINDUSTRY,ANDSHOULDCATERFORAWIDERANGEOFQUALITYOFWORKTHESYSTEMSHOULD,IFPOSSIBLE,BETABULATED,TOSAVETHEUSERTHETROUBLEOFHAVINGTOCALCULATETHELIMITSOFSIZETOSUITOFTHECLASSOFFIT,THEQUALITYOFTHEWORK,ANDTHESIZEOFTHEPART4BRITISHSTANDARD45001969,ISOLIMITSANDFITSTHISSTANDARDREPLACEBS4500ISESSENTIALLYAREVISIONOFBS1961TOBRINGTHEBRITISHSTANDARDINTOLINEWITHTHELATESTRECOMMENDATIONSOFTHEINTERNATIONALORGANIZATIONFORSTANDARDIZATIONISOTHESYSTEMREFERSTOHOLESANDSHAFTS,BUTTHESETERMSDONOTONLYAPPLYTOCYLINDRICALPARTSBUTCANEQUALLYWELLBEAPPLIEDTOTHESPACECONTAINEDBYORCONTAINING,TWOPARALLELFACESORTANGENTPLANESTHESYSTEMISTABULATED,ANDCOVERSSIZESUPTO3150MMTHENUMERICALCONTROL’SDEVELOPMENTTHEFIRSTELECTRONICCOMPUTERINTHEWORLDEMERGEDIN1946,THISINDICATESTHEMANKINDHASCREATEDTHETOOLTHATCANSTRENGTHENANDREPLACETHEMENTALLABOURPARTLYIT,ANDMANKINDTHOSETHATCREATETOSTRENGTHENTOOLOFMANUALLABORCOMPAREAMONGAGRICULTURE,INDUSTRIALSOCIETY,THEQUALITATIVELEAPHASARISEN,HASESTABLISHEDTHEFOUNDATIONTHATTHEMANKINDENTERSTHEINFORMATIONINTENSIVESOCIETY6YEARSLATER,NAMELYIN1952,THETECHNOLOGYOFTHECOMPUTERWASAPPLIEDTOTHELATHE,THEFIRSTNUMERICALCONTROLLATHEHASEMERGEDINUSAFROMTHENON,THETRADITIONALLATHEHADPRODUCEDTHECHANGEOFTHEQUALITYINNEARLYHALFACENTURY,THENUMERICALCONTROLSYSTEMWENTTHROUGHTWOSTAGESANDSIXGENERATIONSDEVELOPMENTTHENUMERICALCONTROLLATHEISREGARDEDASTHEINTEGRATEDTYPICALPRODUCTSOFELECTROMECHANICS,PLAYANENORMOUSROLEAMONGMECHANICALMANUFACTURINGINDUSTRY,SOLVESTRUCTURECOMPLICATED,ACCURATE,BATCHLITTLE,CHANGEABLEPROCESSINGPROBLEMOFPARTINTHEMODERNMACHINEBUILDINGWELL,ANDCANSTABILIZETHEPROCESSINGQUALITYOFTHEPRODUCTS,IMPROVEPRODUCTIONEFFICIENCYBYALARGEMARGINBUTSEENFROMSITUATIONWHICHENTERPRISESFACEATPRESENT,BECAUSETHENUMERICALCONTROLLATHEPRICEISRELATIVELYEXPENSIVE,AMBASSADORSENTERPRISESAREUNABLETODOWHATONEWANTSVERYMUCHTODOTORELATIVELYMAKETHEINVESTMENTONCEONLYOURCOUNTRYCANYETBEREGARDEDASAKINDOFBETTERGOODPLANTOTHENUMERICALCONTROLTRANSFORMATIONOFTHEORDINARYLATHEASTHELATHEBIGCOUNTRYTHISTEXTPROPOSESTOTHEDOMESTICENTERPRISESCURRENTSITUATIONATPRESENTTHEECONOMICNUMERICALCONTROLOFTHESIMPLEANDEASYTYPETRANSFORMSTHETHINKINGANDDESIGNMETHODFORTECHNICALSTAFFOFNUMERICALCONTROLSREFERENCENUMERICALCONTROLTRANSFORMATIONMEANTOORDINARYLATHESOMEPOSITIONMAKECERTAINTRANSFORMATIONGENERALLY,MATCHTHENUMERICALCONTROLDEVICE,THUSMAKETHELATHEHAVEWORKINGABILITYOFNUMERICALCONTROL,ITSPURPOSEISFORIMPROVINGMACHININGACCURACYOFTHEOLDEQUIPMENTANDPRODUCTIONEFFICIENCY,ADAPTTOMANYVARIETYANDPRODUCTION,SHORTRUNOFPART,CANMAKEINDUSTRIALGRADECANPROCESSTHEHIGHQUALITYPARTTOOTHANLOWWORKERATTHESAMETIME,REDUCEINVESTMENTOFTECHNOLOGICALTRANSFORMATIONOFTHEEQUIPMENT,ETCPRICEPERFORMANCEONALLTHESEFORIMPROVINGBEENFORLATHETHAN,NAMELYLASTMECHANICAL

注意事项

本文(外文翻译---尺寸控制.doc)为本站会员(英文资料库)主动上传,人人文库网仅提供信息存储空间,仅对用户上传内容的表现方式做保护处理,对上载内容本身不做任何修改或编辑。 若此文所含内容侵犯了您的版权或隐私,请立即通知人人文库网(发送邮件至[email protected]或直接QQ联系客服),我们立即给予删除!

温馨提示:如果因为网速或其他原因下载失败请重新下载,重复下载不扣分。

关于我们 - 网站声明 - 网站地图 - 资源地图 - 友情链接 - 网站客服客服 - 联系我们

网站客服QQ:2846424093    人人文库上传用户QQ群:460291265   

[email protected] 2016-2018  renrendoc.com 网站版权所有   南天在线技术支持

经营许可证编号:苏ICP备12009002号-5