螺纹联接Screw课件

螺纹联接Screw主讲人：刘宝生12螺纹紧固件及其联接螺纹联接的预紧和防松ThreadedfastenersandtheirconnectionsPretighteningandantilooseningofthreadedconnections目录CONTENTS1螺纹紧固件及其联接ThreadedfastenersandtheirconnectionsONE一、螺纹紧固件及其联接Threadedfastenersandtheirconnections螺纹紧固件是利用螺纹起联接作用，使两个零件联接固定在一起。Threadfastenersusethreadstoconnectandfixtwopartstogether.一、螺纹紧固件及其联接Threadedfastenersandtheirconnections常用的螺纹紧固件:螺栓、双头螺柱、螺母、螺钉、垫圈等。Threadfastenersusethreadstoconnectandfixtwopartstogether.六角头螺栓Hexagonheadedbolt双头螺柱Studbolt六角头螺母Hexagonnut六角开槽螺SlottedHexNut圆螺母Nut内六角圆柱头螺钉Hexagonsocketheadcapscrew开槽圆柱头螺钉Slottedcylindricalheadscrews半圆头螺钉Halfroundheadscrew开槽沉头螺Slottedcountersunkheadscrew钉紧定螺钉Tightenthesetscrew平垫圈flatwasher弹簧垫Washer圆螺母用止动垫圈

Tabwashersforroundnut一、螺纹紧固件及其联接Threadedfastenersandtheirconnections螺纹紧固件的结构形式和尺寸已经标准化，使用时可根据有关标准选取，不需画出零件图，只需写出标记，便于外购。Thestructuralformandsizeofthreadedfastenershavebeenstandardized,andtheycanbeselectedaccordingtorelevantstandardsduringuse.Thereisnoneedtodrawpartdrawings,onlymarkingsneedtobewrittenforeasyoutsourcing.一、螺纹紧固件及其联接Threadedfastenersandtheirconnections螺纹紧固件联接的主要形式Themainformsofthreadedfastenerconnection螺栓联接boltconnection双头螺柱联接Studandnut螺钉联接Screwconnection紧定螺钉联接Tighteningscrewconnection一、螺纹紧固件及其联接Threadedfastenersandtheirconnections1.螺栓联接boltconnectionnutgrommetboltConnectedparts螺栓联接boltconnection螺栓联接剖视图Sectionalviewofboltedconnection孔与螺杆之间留有间隙Leaveagapbetweentheholeandthescrew垫圈的作用是防止拧紧螺母时损伤被联接零件的表面，并使螺母的压力均匀分布到零件表面上。螺栓联接用于联接两个较薄零件。普通螺栓的杆与孔之间有间隙，通孔的加工要求低，结构简单，装拆方便，应用广泛。Thefunctionofthewasheristopreventdamagetothesurfaceoftheconnectedpartswhentighteningthenut,andtoevenlydistributethepressureofthenutonthesurfaceoftheparts.Boltedconnectionsareusedtoconnecttwothinnerparts.Thereisagapbetweentherodandtheholeofordinarybolts,andtheprocessingrequirementsforthroughholesarelow.Thestructureissimple,easytoassembleanddisassemble,anditiswidelyused.一、螺纹紧固件及其联接Threadedfastenersandtheirconnections2.双头螺柱联接StudandnutStuds(threadedonbothends)nutgrommetThinconnector(lighthole)Thickconnector(threadedhole)双头螺柱联接剖视图SectionalViewofDoubleEndStudConnection一、螺纹紧固件及其联接Threadedfastenersandtheirconnections2.双头螺柱联接Studandnut双头螺柱Doubleheadedstuds双头螺柱两端都是螺纹，一端必须全部旋入被联接件螺孔内，称为旋入端;另一端用以拧紧螺母，称为紧固端。Bothendsofthedoubleheadedboltarethreaded,andoneendmustbefullyscrewedintothescrewholeoftheconnectedpart,whichiscalledthescrewedend;Theotherendisusedtotightenthenut,knownasthefasteningend.一、螺纹紧固件及其联接Threadedfastenersandtheirconnections2.双头螺柱联接Studandnut双头螺柱联接剖视图SectionalViewofDoubleEndStudConnection双头螺柱联接用于被联接件之一较厚，不宜于用螺栓联接，较厚的被联接件强度较差，又需经常拆卸的场合。Doubleheadedboltconnectionisusedinsituationswhereoneoftheconnectedpartsisthickandnotsuitableforboltconnection.Thickconnectedpartshavepoorstrengthandrequirefrequentdisassembly.一、螺纹紧固件及其联接Threadedfastenersandtheirconnections3.螺钉联接Screwconnection不用螺母，只用螺钉，直接把螺钉拧进被联接件的螺钉孔中。适用于载荷较轻，且不经常装拆的场合。Nonuts,onlyscrews,directlyscrewthescrewsintothescrewholesoftheconnectedparts.Suitableforoccasionswithlightloadsandinfrequentassemblyanddisassembly.螺钉联接剖视图Sectionalviewofscrewconnection一、螺纹紧固件及其联接Threadedfastenersandtheirconnections3.螺钉联接Screwconnection内六角圆柱头螺钉Hexagonsocketheadcapscrew开槽圆柱头螺钉Slottedcylindricalheadscrews内六角半圆头螺钉Hexagonsockethalfroundheadscrew开槽沉头螺钉Slottedcountersunkheadscrew按头部形状分为:内六角圆柱头、开槽圆柱头、半圆头、沉头螺钉等。Accordingtotheshapeofthehead,itcanbedividedinto:hexagonalcylindricalhead,slottedcylindricalhead,halfroundhead,countersunkheadscrews,etc.一、螺纹紧固件及其联接Threadedfastenersandtheirconnections3.螺钉联接Screwconnection螺钉联接结构简单、紧凑，一般用于两个被联接件中一个较厚，受力不大，且不需要经常拆卸的场合，以免螺纹孔损坏。Thescrewconnectionstructureissimpleandcompact,andisgenerallyusedinsituationswhereoneofthetwoconnectedpartsisthicker,lessstressed,anddoesnotrequirefrequentdisassemblytoavoiddamagetothethreadedhole.螺钉联接剖视图Sectionalviewofscrewconnection一、螺纹紧固件及其联接Threadedfastenersandtheirconnections4.紧定螺钉联接Tighteningscrewconnectiona）平端紧定螺钉Flatendsetscrew利用拧入零件螺纹孔中的螺纹末端顶住另一零件的表面或顶入另一零件上的凹坑中，以固定两个零件的相对位置。Usetheendofthethreadthatisscrewedintothethreadedholeoftheparttopressagainstthesurfaceofanotherpartorintoarecessontheotherparttofixtherelativepositionofthetwoparts.紧定螺钉联接剖视图Sectionalviewoffasteningscrewconnection

b）锥端紧定螺钉Coneendsetscrewc）圆柱端紧定螺钉Cylindricalendsetscrew2螺纹联接的预紧和防松PretighteningandantilooseningofthreadedconnectionsTWO二、螺纹联接的预紧和防松Pretighteningandantilooseningofthreadedconnections1.螺纹联接的预紧Pretighteningofthreadedconnections绝大多数螺纹联接在装配时都必须拧紧，使联接在承受工作载荷之前，预先受到力的作用。Thevastmajorityofthreadedconnectionsmustbetightenedduringassembly,sothattheconnectionissubjectedtoforceinadvancebeforebearingtheworkingload.预紧的目的是增强联接的可靠性和紧密性，以防止受载后被联接件间出现缝隙或发生相对滑移。Thepurposeofpretighteningistoenhancethereliabilityandtightnessoftheconnection,inordertopreventgapsorrelativeslippagebetweentheconnectedpartsafterbeingloaded.对于重要的螺纹联接，应控制其预紧力，因为预紧力的大小对螺纹的可靠性、强度和密封性均有很大的影响。Forimportantthreadedconnections,thepretighteningforceshouldbecontrolled,asthemagnitudeofthepretighteningforcehasasignificantimpactonthereliability,strength,andsealingofthethread.二、螺纹联接的预紧和防松Pretighteningandantilooseningofthreadedconnections(1)定力矩扳手:预先设置一个特定扭矩值的螺纹拧紧工具。扳手的扭矩大小主要靠调节扭矩弹簧得到，而扭矩弹簧是靠调整螺塞得到。Fixedtorquewrench:Athreadedtighteningtoolwithaspecifictorquevaluepre-set.Thetorqueofthewrenchismainlyobtainedbyadjustingthetorquespring,whichisobtainedbyadjustingthescrewplug.二、螺纹联接的预紧和防松Pretighteningandantilooseningofthreadedconnections(2)测力矩扳手:指针式扭矩扳手除内装扭矩产生及控制机构外，还装有一只外露扭矩表，能随时指示出施加的扭矩值。它也可作扭矩值的校准工具，通过扭矩表直接指示并读出所施加的扭矩值。Torquemeasuringwrench:Inadditiontothebuilt-intorquegenerationandcontrolmechanism,thepointertypetorquewrenchisalsoequippedwithanexposedtorquegaugethatcanindicatetheappliedtorquevalueatanytime.Itcanalsobeusedasacalibrationtoolfortorquevalues,directlyindicatingandreadingtheappliedtorquevaluethroughatorquemeter.二、螺纹联接的预紧和防松Pretighteningandantilooseningofthreadedconnections2.螺纹联接的防松Antilooseningofthreadedconnections在冲压、振动或变载荷的作用下，联接可能失去自锁作用而松脱，使联接失效，造成事故。Undertheactionofstamping,vibration,orvariableload,theconnectionmayloseitsself-lockingeffectandbecomeloose,causingtheconnectiontofailandcausingaccidents.防松:防止螺纹副的相对转动。Antiloosening:preventstherelativerotationofthethreadedpair.按工作原理不同，可分为三类:摩擦防松、机械防松(直接锁住)和破坏螺纹副的运动关系防松。Accordingtodifferentworkingprinciples,itcanbedividedintothreecategories:frictionantiloosening,mechanicalantiloosening(directlylocking),andantilooseningthatdamagesthemotionrelationshipofthethreadedpair.二、螺纹联接的预紧和防松Pretighteningandantilooseningofthreadedconnections2.螺纹联接的防松Antilooseningofthreadedconnections(1)摩擦力防松:使螺纹联接中的摩擦不随外载荷增加而减小或加大阻力矩。Frictionprevention:topreventthefrictioninthreadedconnectionsfromdecreasingorincreasingtheresistancemomentwiththeincreaseofexternalload.图1双螺母防松Figure1Doublenutantiloosening图2尼龙锁紧圈防松looseningFigure2Nylonlockingringantiloosening两螺母对顶，螺栓始终受到附加拉力和附加摩擦力的作用Twonutsarefacingeachother,andtheboltisalwayssubjectedtoadditionaltensionandfriction拧紧后尼龙圈内孔被螺栓箍紧而起到防松Aftertightening,theinnerholeofthenylonringistightenedbyboltstopreventloosening二、螺纹联接的预紧和防松Pretighteningandantilooseningofthreadedconnections2.螺纹联接的防松Antilooseningofthreadedconnections(2)利用联接件的形状防松:利用附加零件的形状或改变螺纹联接形状，使被联接件不能相对运动。

Usingtheshapeoftheconnectingpartstopreventloosening:Usingtheshapeofadditionalpartsorchangingtheshapeofthreadedconnectionstopreventrelativemovementoftheconnectedparts.图1开口销和带槽螺母防松Figure1Cotterpinandslottednutantiloosening图2带翅垫片防松Figure2Antilooseningofwingedgasket槽形螺母拧紧后，开口销从螺母的槽口和螺栓尾部的孔中穿过，起到防松作用Aftertighteningthegroovenut,thecotterpinpassesthroughthegrooveofthenutandtheholeattheendofthebolttopreventloosening拧紧螺母后，将垫片外翅之一折嵌于螺母的一个槽内，起到防松作用Aftertighteningthenut,foldoneoftheouterwingsofthegasketintoagrooveofthenuttopreventloosening二、螺纹联接的预紧和防松Pretighteningandantilooseningofthreadedconnections2.螺纹联接的防松Antilooseningofthreadedconnections(2)利用联接件的形状防松:利用附加零件的形状或改变螺纹联接形状，使被联接件不能相对运动。

Usingtheshapeoftheconnectingpartstopreventloosening:Usingtheshapeofadditionalpartsorchangingtheshapeofthreadedconnectionstopreventrelativemovementoftheconnectedparts.将垫片折边，分别弯靠在螺母和被联接件的侧边，以固定螺母和被联接件的相对位置，起到防松作用Twonutsarefacingeachother,andtheboltisalwayssubjectedtoadditionaltensionandfriction图3止动垫片防松Figure3Lockingwasherantiloosening图4金属丝防松Figure4Metalwireantiloosening利用钢丝使一组螺栓头部相互约束，无法松动，防松可靠,用于高速、振动、冲击等场合Usingsteelwiretoconstrainagroupofboltheadstoeachother,preventinglooseningandensuringreliableantiloosening.Usedinhigh-speed,vibration,impact,andothersituations二、螺纹联接的预紧和防松Pretighteningandantilooseningofthreadedconnections2.螺纹联接的防松Antilooseningofthreadedconnections（3）利用附加材料防松：将螺母焊死在螺杆上，或者用粘合剂涂在旋合螺纹表面，粘合剂硬化后固连零件，还可以起到密封作用，此法适合不拆卸防松用。Usingadditionalmate