外文翻译-起重机的用途与历史

毕业设计中英文翻译起重机的用途与历史学生姓名学号学院机械工程与自动化学院专业机械设计制造及其自动化指导教师年06月THEUSEANDHISTORYOFCRANEEVERYTIMEWESEEACRANEINACTIONWEREMAINSWITHOUTWORDS,THESEMACHINESARESOMETIMESREALLYHUGE,TAKINGUPTONSOFMATERIALHUNDREDSOFMETERSINHEIGHTWEWATCHWITHAMAZEMENTANDABITOFTERROR,THINKINGABOUTWHATWOULDHAPPENIFTHELOADCOMESOFFORIFTHEMOVEMENTOFTHECRANEWASWRONGITISAREALLYFASCINATINGSYSTEM,SURPRISINGBOTHADULTSANDCHILDRENTHESEAREESPECIALLYTOWERCRANES,BUTINREALITYTHEREAREPLENTYOFTYPESANDTHEYAREINUSEFORCENTURIESTHECRANESAREFORMEDBYONEORMOREMACHINESUSEDTOCREATEAMECHANICALADVANTAGEANDTHUSMOVELARGELOADSCRANESAREEQUIPPEDWITHAWINDER,AWIREROPEORCHAINANDSHEAVESTHATCANBEUSEDBOTHTOLIFTANDLOWERMATERIALSANDTOMOVETHEMHORIZONTALLYITUSESONEORMORESIMPLEMACHINESTOCREATEMECHANICALADVANTAGEANDTHUSMOVELOADSBEYONDTHENORMALCAPABILITYOFAHUMANCRANESARECOMMONLYEMPLOYEDINTHETRANSPORTINDUSTRYFORTHELOADINGANDUNLOADINGOFFREIGHT,INTHECONSTRUCTIONINDUSTRYFORTHEMOVEMENTOFMATERIALSANDINTHEMANUFACTURINGINDUSTRYFORTHEASSEMBLINGOFHEAVYEQUIPMENT1OVERVIEWTHEFIRSTCONSTRUCTIONCRANESWEREINVENTEDBYTHEANCIENTGREEKSANDWEREPOWEREDBYMENORBEASTSOFBURDEN,SUCHASDONKEYSTHESECRANESWEREUSEDFORTHECONSTRUCTIONOFTALLBUILDINGSLARGERCRANESWERELATERDEVELOPED,EMPLOYINGTHEUSEOFHUMANTREADWHEELS,PERMITTINGTHELIFTINGOFHEAVIERWEIGHTSINTHEHIGHMIDDLEAGES,HARBORCRANESWEREINTRODUCEDTOLOADANDUNLOADSHIPSANDASSISTWITHTHEIRCONSTRUCTIONSOMEWEREBUILTINTOSTONETOWERSFOREXTRASTRENGTHANDSTABILITYTHEEARLIESTCRANESWERECONSTRUCTEDFROMWOOD,BUTCASTIRONANDSTEELTOOKOVERWITHTHECOMINGOFTHEINDUSTRIALREVOLUTIONFORMANYCENTURIES,POWERWASSUPPLIEDBYTHEPHYSICALEXERTIONOFMENORANIMALS,ALTHOUGHHOISTSINWATERMILLSANDWINDMILLSCOULDBEDRIVENBYTHEHARNESSEDNATURALPOWERTHEFIRSTMECHANICALPOWERWASPROVIDEDBYSTEAMENGINES,THEEARLIESTSTEAMCRANEBEINGINTRODUCEDINTHE18THOR19THCENTURY,WITHMANYREMAININGINUSEWELLINTOTHELATE20THCENTURYMODERNCRANESUSUALLYUSEINTERNALCOMBUSTIONENGINESORELECTRICMOTORSANDHYDRAULICSYSTEMSTOPROVIDEAMUCHGREATERLIFTINGCAPABILITYTHANWASPREVIOUSLYPOSSIBLE,ALTHOUGHMANUALCRANESARESTILLUTILIZEDWHERETHEPROVISIONOFPOWERWOULDBEUNECONOMIC2HISTORYANCIENTGREECETHECRANEFORLIFTINGHEAVYLOADSWASINVENTEDBYTHEANCIENTGREEKSINTHELATE6THCENTURYBCTHEARCHAEOLOGICALRECORDSHOWSTHATNOLATERTHANC515BCDISTINCTIVECUTTINGSFORBOTHLIFTINGTONGSANDLEWISIRONSBEGINTOAPPEARONSTONEBLOCKSOFGREEKTEMPLESSINCETHESEHOLESPOINTATTHEUSEOFALIFTINGDEVICE,ANDSINCETHEYARETOBEFOUNDEITHERABOVETHECENTEROFGRAVITYOFTHEBLOCK,ORINPAIRSEQUIDISTANTFROMAPOINTOVERTHECENTEROFGRAVITY，THEYAREREGARDEDBYARCHAEOLOGISTSASTHEPOSITIVEEVIDENCEREQUIREDFORTHEEXISTENCEOFTHECRANETHEINTRODUCTIONOFTHEWINCHANDPULLEYHOISTSOONLEADTOAWIDESPREADREPLACEMENTOFRAMPSASTHEMAINMEANSOFVERTICALMOTIONFORTHENEXTTWOHUNDREDYEARS,GREEKBUILDINGSITESWITNESSEDASHARPDROPINTHEWEIGHTSHANDLED,ASTHENEWLIFTINGTECHNIQUEMADETHEUSEOFSEVERALSMALLERSTONESMOREPRACTICALTHANOFFEWERLARGERONESINCONTRASTTOTHEARCHAICPERIODWITHITSTENDENCYTOEVERINCREASINGBLOCKSIZES,GREEKTEMPLESOFTHECLASSICALAGELIKETHEPARTHENONINVARIABLYFEATUREDSTONEBLOCKSWEIGHINGLESSTHAN1520TONSALSO,THEPRACTICEOFERECTINGLARGEMONOLITHICCOLUMNSWASPRACTICALLYABANDONEDINFAVOROFUSINGSEVERALCOLUMNDRUMSALTHOUGHTHEEXACTCIRCUMSTANCESOFTHESHIFTFROMTHERAMPTOTHECRANETECHNOLOGYREMAINUNCLEAR,ITHASBEENARGUEDTHATTHEVOLATILESOCIALANDPOLITICALCONDITIONSOFGREECEWEREMORESUITABLETOTHEEMPLOYMENTOFSMALL,PROFESSIONALCONSTRUCTIONTEAMSTHANOFLARGEBODIESOFUNSKILLEDLABOR,MAKINGTHECRANEMOREPREFERABLETOTHEGREEKPOLISTHANTHEMORELABORINTENSIVERAMPWHICHHADBEENTHENORMINTHEAUTOCRATICSOCIETIESOFEGYPTORASSYRIATHEFIRSTUNEQUIVOCALLITERARYEVIDENCEFORTHEEXISTENCEOFTHECOMPOUNDPULLEYSYSTEMAPPEARSINTHEMECHANICALPROBLEMSMECH18，853A32853BL3ATTRIBUTEDTOARISTOTLE384322BC,BUTPERHAPSCOMPOSEDATASLIGHTLYLATERDATEAROUNDTHESAMETIME,BLOCKSIZESATGREEKTEMPLESBEGANTOMATCHTHEIRARCHAICPREDECESSORSAGAIN,INDICATINGTHATTHEMORESOPHISTICATEDCOMPOUNDPULLEYMUSTHAVEFOUNDITSWAYTOGREEKCONSTRUCTIONSITESBYTHENANCIENTROMETHEHEYDAYOFTHECRANEINANCIENTLIMESCAMEDURINGTHEROMANEMPIRE,WHENCONSTRUCTIONACTIVITYSOAREDANDBUILDINGSREACHEDENORMOUSDIMENSIONSTHEROMANSADOPTEDTHEGREEKCRANEANDDEVELOPEDITFURTHERWEARERELATIVELYWELLINFORMEDABOUTTHEIRLIFTINGTECHNIQUESTHESIMPLESTROMANCRANE，THETRISPASTOS,CONSISTEDOFASINGLEBEAMJIB,AWINCH,AROPE,ANDABLOCKCONTAININGTHREEPULLEYSHAVINGTHUSAMECHANICALADVANTAGEOF31,ITHASBEENCALCULATEDTHATASINGLEMANWORKINGTHEWINCHCOULDRAISE150KG3PULLEYSX50KG150,ASSUMINGTHAT50KGREPRESENTTHEMAXIMUMEFFORTAMANCANEXERTOVERALONGERTIMEPERIODHEAVIERCRANETYPESFEATUREDFIVEPULLEYSPENTASPASTOSOR,INCASEOFTHELARGESTONE,ASETOFTHREEBYFIVEPULLEYSPOLYSPASTOSANDCAMEWITHTWO,THREEORFOURMASTS,DEPENDINGONTHEMAXIMUMLOADTHEPOLYSPASTOS,WHENWORKEDBYFOURMENATBOTHSIDESOFTHEWINCH，COULDALREADYLIFT3000KG3ROPESX5PULLEYSX4MENX50KG30HKGINCASETHEWINCHWASREPLACEDBYATREADWHEEL,THEMAXIMUMLOADEVENDOUBLEDTO6000KGATONLYHALFTHECREW,SINCETHETREADWHEELPOSSESSESAMUCHBIGGERMECHANICALADVANTAGEDUETOITSLARGERDIAMETERTHISMEANTTHAT,INCOMPARISONTOTHECONSTRUCTIONOFTHEEGYPTIANPYRAMIDS,WHEREABOUT50MENWERENEEDEDTOMOVEA25TONSTONEBLOCKUPTHERAMP50KGPERPERSON,THELIFTINGCAPABILITYOFTHEROMANPOLYSPASTOSPROVEDTOBE60TIMESHIGHER3000KGPERPERSONHOWEVER,NUMEROUSEXTANTROMANBUILDINGSWHICHFEATUREMUCHHEAVIERSTONEBLOCKSTHANTHOSEHANDLEDBYTHEPOLYSPASTOSINDICATETHATTHEOVERALLLIFTINGCAPABILITYOFTHEROMANSWENTFARBEYONDTHATOFANYSINGLECRANEATTHETEMPLEOFJUPITERATBAALBEK,FORINSTANCE,THEARCHITRAVEBLOCKSWEIGHUPTO60TONSEACH，ANDONECORNERCORNICEBLOCKEVENOVER100TONS,ALLOFTHEMRAISEDTOAHEIGHTOFABOUT19MINROME,THECAPITALBLOCKOFTRAJANSCOLUMNWEIGHS533TONS,WHICHHADTOBELIFTEDTOAHEIGHTOFABOUT34MSEECONSTRUCTIONOFTRAJARTSCOLUMNMIDDLEAGESDURINGTHEHIGHMIDDLEAGES,THETREADWHEELCRANEWASREINTRODUCEDONALARGESCALEAFTERTHETECHNOLOGYHADFALLENINTODISUSEINWESTERNEUROPEWITHTHEDEMISEOFTHEWESTERNROMANEMPIRETHEEARLIESTREFERENCETOATREADWHEELMAGNAROTAREAPPEARSINARCHIVALLITERATUREINFRANCEABOUT1225,FOLLOWEDBYANILLUMINATEDDEPICTIONINAMANUSCRIPTOFPROBABLYALSOFRENCHORIGINDATINGTO1240INNAVIGATION,THEEARLIESTUSESOFHARBORCRANESAREDOCUMENTEDFORUTRECHTIN1244，ANTWERPIN1263，BRUGGEIN1288ANDHAMBURGIN1291,WHILEINENGLANDTHETREADWHEELISNOTRECORDEDBEFORE1331GENERALLY,VERTICALTRANSPORTCOULDBEDONEMORESAFELYANDINEXPENSIVELYBYCRANESTHANBYCUSTOMARYMETHODSTYPICALAREASOFAPPLICATIONWEREHARBORS,MINES,AND,INPARTICULAR,BUILDINGSITESWHERETHETREADWHEELCRANEPLAYEDAPIVOTALROLEINTHECONSTRUCTIONOFTHELOFTYGOTHICCATHEDRALSNEVERTHELESS,BOTHARCHIVALANDPICTORIALSOURCESOFTHETIMESUGGESTTHATNEWLYINTRODUCEDMACHINESLIKETREADWHEELSORWHEELBARROWSDIDNOTCOMPLETELYREPLACEMORELABORINTENSIVEMETHODSLIKELADDERS,HODSANDHANDBARROWSRATHER,OLDANDNEWMACHINERYCONTINUEDTOCOEXISTONMEDIEVALCONSTRUCTIONSITESANDHARBORSAPARTFROMTREADWHEELS,MEDIEVALDEPICTIONSALSOSHOWCRANESTOBEPOWEREDMANUALLYBYWINDLASSESWITHRADIATINGSPOKES,CRANKSANDBYTHE15THCENTURYALSOBYWINDLASSESSHAPEDLIKEASHIPSWHEELTOSMOOTHOUTIRREGULARITIESOFIMPULSEANDGETOVERDEADSPOTSINTHELIFTINGPROCESSFLYWHEELSAREKNOWNTOBEINUSEASEARLYAS1123THEEXACTPROCESSBYWHICHTHETREADWHEELCRANEWASREINTRODUCEDISNOTRECORDED,ALTHOUGHITSRETURNTOCONSTRUCTIONSITESHASUNDOUBTEDLYTOBEVIEWEDINCLOSECONNECTIONWITHTHESIMULTANEOUSRISEOFGOTHICARCHITECTURETHEREAPPEARANCEOFTHETREADWHEELCRANEMAYHAVERESULTEDFROMATECHNOLOGICALDEVELOPMENTOFTHEWINDLASSFROMWHICHTHETREADWHEELSTRUCTURALLYANDMECHANICALLYEVOLVEDALTERNATIVELY,THEMEDIEVALTREADWHEELMAYREPRESENTADELIBERATEREINVENTIONOFITSROMANCOUNTERPARTDRAWNFROMVITRUVIUSDEARCHITECTURAWHICHWASAVAILABLEINMANYMONASTICLIBRARIESITSREINTRODUCTIONMAYHAVEBEENINSPIRED，ASWELL，BYTHEOBSERVATIONOFTHELABORSAVINGQUALITIESOFTHEWATERWHEELWITHWHICHEARLYTREADWHEELSSHAREDMANYSTRUCTURALSIMILARITIESSTRUCTUREANDPLACEMENTTHEMEDIEVALTREADWHEELWASALARGEWOODENWHEELTURNINGAROUNDACENTRALSHAFTWITHATREADWAYWIDEENOUGHFORTWOWORKERSWALKINGSIDEBYSIDEWHILETHEEARLIERCOMPASSARMWHEELHADSPOKESDIRECTLYDRIVENINTOTHECENTRALSHAFT，THEMOREADVANCEDCLASPARNVTYPEFEATUREDARMSARRANGEDASCHORDSTOTHEWHEELRIM,GIVINGTHEPOSSIBILITYOFUSINGATHINNERSHAFTANDPROVIDINGTHUSAGREATERMECHANICALADVANTAGECONTRARYTOAPOPULARLYHELDBELIEF,CRANESONMEDIEVALBUILDINGSITESWERENEITHERPLACEDONTHEEXTREMELYLIGHTWEIGHTSCAFFOLDINGUSEDATTHETIMENORONTHETHINWALLSOFTHEGOTHICCHURCHESWHICHWEREINCAPABLEOFSUPPORTINGTHEWEIGHTOFBOTHHOISTINGMACHINEANDLOADRATHER,CRANESWEREPLACEDINTHEINITIALSTAGESOFCONSTRUCTIONONTHEGROUND，OFTENWITHINTHEBUILDINGWHENANEWFLOORWASCOMPLETED,ANDMASSIVETIEBEAMSOFTHEROOFCONNECTEDTHEWALLS,THECRANEWASDISMANTLEDANDREASSEMBLEDONTHEROOFBEAMSFROMWHEREITWASMOVEDFROMBAYTOBAYDURINGCONSTRUCTIONOFTHEVAULTSTHUS,THECRANEGREWANDWANDEREDWITHTHEBUILDINGWITHTHERESULTTHATTODAYALLEXTANTCONSTRUCTIONCRANESINENGLANDAREFOUNDINCHURCHTOWERSABOVETHEVAULTINGANDBELOWTHEROOF，WHERETHEYREMAINEDAFTERBUILDINGCONSTRUCTIONFORBRINGINGMATERIALFORREPAIRSALOFTHARBORUSAGEACCORDINGTOTHE“PRESENTSTATEOFKNOWLEDGE”UNKNOWNINANTIQUITY,STATIONARYHARBORCRANESARECONSIDEREDANEWDEVELOPMENTOFTHEMIDDLEAGESTHETYPICALHARBORCRANEWASAPIVOTINGSTRUCTUREEQUIPPEDWITHDOUBLETREADWHEELSTHESECRANESWEREPLACEDDOCKSIDESFORTHELOADINGANDUNLOADINGOFCARGOWHERETHEYREPLACEDORCOMPLEMENTEDOLDERLIFTINGMETHODSLIKESEESAWS,WINCHESANDYARDSTWODIFFERENTTYPESOFHARBORCRANESCANBEIDENTIFIEDWITHAVARYINGGEOGRAPHICALDISTRIBUTIONWHILEGANTRYCRANESWHICHPIVOTEDONACENTRALVERTICALAXLEWERECOMMONLYFOUNDATTHEFLEMISHANDDUTCHCOASTSIDE,GERMANSEAANDINLANDHARBORSTYPICALLYFEATUREDTOWERCRANESWHERETHEWINDLASSANDTREADWHEELSWERESITUATEDINASOLIDTOWERWITHONLYJIBARMANDROOFROTATINGINTERESTINGLY,DOCKSIDECRANESWERENOTADOPTEDINTHEMEDITERRANEANREGIONANDTHEHIGHLYDEVELOPEDITALIANPORTSWHEREAUTHORITIESCONTINUEDTORELYONTHEMORELABORINTENSIVEMETHODOFUNLOADINGGOODSBYRAMPSBEYONDTHEMIDDLEAGESUNLIKECONSTRUCTIONCRANESWHERETHEWORKSPEEDWASDETERMINEDBYTHERELATIVELYSLOWPROGRESSOFTHEMASONS,HARBORCRANESUSUALLYFEATUREDDOUBLETREADWHEELSTOSPEEDUPLOADINGTHETWOTREADWHEELSWHOSEDIAMETERISESTIMATEDTOBE4MORLARGERWEREATTACHEDTOEACHSIDEOFTHEAXLEANDROTATEDTOGETHERTODAY,ACCORDINGTOONESURVEY,FIFTEENTREADWHEELHARBORCRANESFROMPREINDUSTRIALTIMESARESTILLEXTANTTHROUGHOUTEUROPE28BESIDETHESESTATIONARYCRANES,FLOATINGCRANESWHICHCOULDBEFLEXIBLYDEPLOYEDINTHEWHOLEPORTBASINCAMEINTOUSEBYTHE14THCENTURYRENAISSANCEMECHANICALPRINCIPLESTHEREARETWOMAJORCONSIDERATIONSINTHEDESIGNOFCRANESTHEFIRSTISTHATTHECRANEMUSTBEABLETOLIFT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了这样新型的提升物料的技术，它利用了一些小型的石块来来代替人块的石头，这样更具实用性。与更早先的古希腊人神殿的建筑材料的尺寸不断变得越来越大趋势相比较，希腊古典庙宇比如帕台农神庙的石块重景都小于1520吨。而且，要把巨型的石柱竖立起来的作业使希腊人实际上更喜欢用好几块像鼓一样的圆柱石块堆叠而成。尽管确切何时从斜坡运输进入起重机提升技术时代的时间还不是很淸楚。但是当时古希腊不稳定的社会周势、和政治情况使得建造神殿更适合雇佣小观的、更加专业的建筑团队而不是像埃及和亚述那样大量使用的没有技术的分动力。这样的情况使得起重机更像希腊城邦发明的而非釆用纯究动力斜坡运送货物的埃及或是亚述那样的独裁国家。文学上第一次的明确的记载滑轮组的复合系统是出现在亚里士多德的机械难题中，但清楚组成文字可能还要稍晚一些。与此同时，用于建造希腊神庙的石块尺寸再一次开始赶上他们的古代前辈了，这标志着当时更多的久经考验的的滑轮组在希腊建筑史上找到了它们的一席之地。22古罗马时期起重机械在古代的全盛时期却足在古罗马帝国展幵的。当时建筑物的数景激增，而且这些建筑都达到了巨型的尺寸。罗马人采用了希腊人的起重机并将其发扬光大。多亏了那些维特兽程师们撰写的相当冗长的文献和亚历山大帝的苍鹭的巢，我们才得以如此详细地了解到了它们的其中技术。三饼滑车是古罗马最简单的一种起重机，它是由一个单梁吊臂、一个绞盘、一条绳子和一个三个滑轮组成的滑轮组组成的。经计算，假设一个人用尽力气能够长时间地提起相当于重50千克的物体那么通过这样的起重机械他以提升约150千克的物体3个滑轮X50千克150千克）。更加重型的起重机就拥有五个滑轮（五饼滑车），最大的起重机会在两根、三根甚至是四根桅杆上面装上三饼和五饼的复合滑轮组（复滑车），这足由最大的负载载荷决定的。复滑车工作的时候两边需要4个人两边各站两个已经可以提起重约3000千克的物体（3条绳子X5个滑轮X4个人X50千克3000千克）。如果用踏车来代替绞盘的话，最大的起重载荷可以在人工减半的情况下达到两倍一6000千克，因为踏车有更大的直径能够提供多个人的力矩。这意味着，和建造埃及金字塔时50个人才能通过斜坡搬动25吨的石块（50千克每人）的情况相比，罗马的复滑车的提升能力把工作的效率提高60倍（3000千克每人）。然而，大量现存的古罗马建筑中那些石块的重量比复滑车所能操作的负载耍重得多。这表明古罗马人全面的起重的能力要远远大于任何简单的起重机。以BAALBEK的JUPITER神庙为例，那些楣梁的石块每块都重达60吨以上，每个檐口的石块甚至达到了100吨以上，所有这些石料都被提升到了19M的半空中。在罗马TRAJAN之柱的主要石块重达533吨，而这些石块必须被提升到34M的高度。（见TRAJIAN之柱）23中世纪时期在中世纪时，随着西罗马帝国的灭亡，欧洲的科技技术水平一落千丈。这时踏车式的起重机再次被大范围地使用。最早的提到踏车式是大约1225年法国的一部档案文学作品，它在一份手稿上也说明叙述了直到1240年法国人的血统起源。在航海方面，最大的港口起重机是在1244年的UTRECHT、1263年的ANTWERP、1288年的BRUGGE和1291年的HAMBURG,而在英格兰踏车式的起重机直到1331年才有所记录。一般来说，釆用起重机来垂直运输比传统的方法更加的安全和经济。典型的应用领域就包括港口、矿井。值得一提的是在哥特式人教堂的建造过程中，踏车式的起重机起到了一个不可成缺的重要作用。但是，档案和图画都显示了当时新引进的机械系统如踏车、独轮手推车等却没有完全替代那些楼梯、木桶、手推车等依赖劳动力的生产方法。这样，旧式的和新式的机械在继续在中世纪的建筑和港口共存。除了踏车，中世纪的文献中也记载了由手动驱动带幅轮和曲柄的绞盘的起重机，在15世纪时也是由卷扬机发展成为了类似船轮的系统。为了缓冲这些不规则的冲击力和解决提升过程中的死点问题，调速轮最早在1123年开始投入使用。踏车式起觅机具体以何种方式再次被釆用的已经无从考证，尽管它多次被使用在建筑领域，被毋庸置疑地认为和哥特式建筑的崛起有相当密切的关系。踏车式起重机的再次出现可能导致了卷扬机的技术发展，因为卷扬机在踏车式起重机的结构和机械方面都有所发展。中世纪的踏车可以看作是罗马VITRUVIUSDE工程师设计品的一个精心改造品，它们可以在很多寺庙馆藏中看到。3结构与用途中世纪的踏车结构是由一个木轮围绕在一根中心轴上，中心轴的两旁有足够宽的踏板以供两旁的工人踩踏。虽然以前的圆盘臂奋轮辐可以直接用来驱动中心轴，更为先进的