英语由军亮陈频阳张晓勇邓超.ppt

小组 由军亮陈频阳张小勇邓超Team YouJunliangChenPinyangZhangXiaoyongDengChao 工程机械专业英语ConstructionMachineryProfessionalEnglish 2 Zhangxiaoyong Youjunliang Chenpinyang Dengchao Self introduction 3 Hello Mydearteacher Mynameisyoujunliang IcomefromDINGZHOU HEBEIprovince Iamatallboywithshortblackhair 4 I magoodteamplayer I mahard working persistentperson Ihavestrongorganizationalskills Teamwork 5 Myhobbyisdoingsports especiallyplayingbasketball Ioftenplaywithmyfriendsafterschool Ithinkitisgreatfun IlikewatchNBA AsallweknowYaoisthebestplayerfromChina IlikeYao sshowinginNBA 6 Inadditiontoplayingbasketball IalsoliketoplayPCgames AlotofgrownupsthinkplayingPCgameshindersthestudentsfromlearning 7 IthinkPCgamescouldmotivatemetolearnsomethingsuchasEnglish 8 Ithinklanguageisveryinteresting Icouldexpressonesubstancebyusingdifferentsounds SoIwishIcouldstudyandreadmoreEnglishliteraturesandenlargemyknowledge 9 That sallmyself thankyou 10 SelfIntroduction Hello I mChenPinyang agirlwholikessmile I m22nowandthereisashorttimeformeincollege maybe afterfewmonthsIwillbeayoungladywhoaretakingacalm dispassionateviewofthesituation 11 MyHometown Xiangxiang 12 This sthefamousresort YunMenTempleinourhomntown 13 Iliketravel IhopeIhavethechancestovisitTibet 14 Ilikeallthefriendsaroundme it sthemostvaluablememoryincollege 15 Asanoldsayinggoes NothingisimpossibleifyousetyourmindtodoitIconsideritasmymotto MynameisZhangXiaoYong IwasborninX inYuJiangXi Itisabeautifulcity IstartedlearningEnglishsinceIwas12yearsold Inmysparetime IliketodoanythingrelatingtoEnglishsuchaslisteningtoEnglishsongs 17 Ilikeacomputer Iwanttoseethesea Iusedtogoabroadforashort termEnglishstudy Thereare5peopleinmyfamily Myfatherworkinafactory Mymotherworkathome Ihavetwosisters Otherworkinshanghai anotherinthehome Ihaveworkedveryhardatmymajorcourses soastolayasolidfoundationoftheoreticalknowledge 18 Iwanttotraveltheworld whichismydream Iwouldliketoapplyforthepostofindustrialengineer whichyourcompanyoffered IfeelthatIamtherightsortofpersonforthepostbecausemyqualificationsandexperiencearereallysuitablefortheposition 19 Mymottoisthatthesuccessbelongstothosewhoareprepared 20 Hello everyone Plea seallowmetointroducemyself MychinesenameisDengchao andmyEnglishisNicky YoucancallmeNickythelikeit 21 IamfromHunanprovince Myhometownisaquietandbeautifulvillage Thevillagersareverykind hearted ihaveaccumulatedalotofworkingexperienceandpracticalknowledge Inmyopinion thiscityisacompetitiveandchallengingone ilikethiscity Itmakesmestrongerandstronger 22 Also Ilikemakingfriendswithdifferentpeople especiallythosewhoardeasy goingandopen minded Whenyougetalongwithmeforawhile youwillfinditeastandhappytocommunicatewithme What smore I mhelpful Asitisknown godhelpsandtryourbesttorescuethemoutofthetrouble Asanoldsayinggoes NothingisimpossibleifyousetyourmindtodoitIconsideritasmymotto Iamstrong mindedtochallengeeverythingnomatterhowserioustheresultwiube 23 24 Ourhomework 25 Anothertypeoftwo pressuresystememployswhatistermedadifferentialunloadinggovernor Itisappliedinahigh lowortwo pumpcircuit Thegovernorautomatically throughpressuresensing unloadsthelargevolumepumptoaminimumdeadheadpressuresetting 另一种双压力系统采用的是可以应用在高 低压或者双作用泵回路的卸载控制器 通过压力传感 控制器自动对大容积泵卸载到空载压力状态 Paragraph1 26 Deadheadpressurereferstoaspecificpressurelevelestablishedasaresultingactionofthevariable displacement pumpcontrolmechanism Thepumpingactionandtheresultingfluidflowatdeadheadconditionareequaltotheleakageinthesystemandpilot controlflowrequirements空载压力指的是由于变量泵控制机构作用所形成的一种特殊压力级 空载状态下泵的功率和流量相与系统和控制回路的泄漏 27 Nomajorpowermovementoccursatthistime eventhoughthehydraulicsystemmaybeprovidingaclampingorholdingactionwhilethepumpisindeadheadposition 尽管泵在空载位置也可能有夹持等动作发生 但是此时没有大功率运动 28 Thegovernorisbasicallyahydraulicallyoperated two pressurecontrolwithadifferentialpistonthatallowscompleteunloadingwhensufficientexternalpilotpressureisappliedtothepilotunloadport Paragraph2 29 控制器是基于液动操作 当一个有效的外部控制压力加载在卸载口时候 在一个不同的位置 双压控制容许完全卸载 TranslateParagraph2 30 TheminimumdeadheadpressuresettingiscontrolledbythemaingovernorspringA Themaximumpressureiscontrolledbytherelief valveadjustmentB Theoperatingpressureforthegovernorisgeneratedbythelarge volumepumpandentersthroughorificeC Paragraph3 31 最小空载压力是主控制弹簧A控制的 最大压力由溢流阀B决定 控制器的控制压力来自于大容积泵C TranslateParagraph3 32 Tousethisdeviceletusassumethatthecircuitrequiresamaximumpressureof1000psi whichwillbesuppliedbya5 gpmpump Italsoneedsalargeflowatapressureupto500psi itcontinuesto1000psiatthereducedflowrate Paragraph4 让我们假设回路要求的最大压力为1000psi 由一个5gpm的泵提供 在压力达到500psi的时候需要一个大的流量 随着增压到1000psi流量按比例减小 33 Atwo pumpsystemwithanunloadinggovernoronthe40 gpypumpwillprovidetheneeds 含有一个40gpm泵及卸载控制器的双泵系统就能满足流量要求 34 Wecanunloadthe40 gpmpumpat500psitoaminimumpressuresettingof200psi whichthe5 gpmpumptakesthecircuitupto1000psiormore 我们在500psi下卸载40gpm泵到最小压力200psi 这时5gpm的泵就能使回路加压到1000psi甚至更高 Paragraph5 35 NoteinFigurethattwosourceofpilotpressurearerequired One the40 gpmpump providespressurewithinthehousingsothatmaximumpressuresettingcanbeobtained Thesettingofthespring 如图要求两个控制压力源 一个40 gpm的泵 提供最大压力 弹簧的设置 降低了控制器内的压力 决定了40 gpm泵的最大压力 Paragraph6 36 Thesecondpilotsourceiscircuitproper whichwillgoto1000psi ThispilotlineentersthegovernorthroughorificeDandactsontheunloadingpistonE TheareaofpistonEis15 percentgreaterthantheeffectiveareaofthereliefpoppetF 第二个控制源是主回路 能达到1000psi 这条控制线进入控制器 作用在卸载位置 活塞E的面积比安全阀中提动阀F的有效面积大15 37 hegovernorwillunloadat500psiandbeactivatedat15percentbelow500psi or450psi Byunloading wecanmeanzeroflowoutputofthe40 gpmpump 因此这个卸载控制器的不同就在这15 上 控制器在500psi卸载 在425psi工作 所谓卸载 就是指每分钟40加仑流量的泵无输出流量 38 Aspressureinthecircuitincreasesfromzeroto500psi thepressurewithinthegovernorhousingalsoincreaseuntiltherelief valvesettingisreached atwhichtimetherelief valvecracksopen allowingflowtothetank 随着回路中的压力从0增长到500psi 控制器的压力也随着增长 直到达到溢流阀的调定压力 此时溢流阀开启 油液回到油箱 Paragraph7 39 Thepressuredropinthehousingisamaximumadditivevalue allowingthepumptodeadhead Meanwhile thesystempressurecontinuestoriseabove700psi resultinginagreaterforceonthebuttonofpistonEonthetop 腔内的压力降是个最大的叠加值 容许泵空载 同时系统压力连续增长到700psi以上 导致活塞底部的压力比上部大 Paragraph8 40 ThepistonthencompletelyunseatspopetF whichresultsinafurtherpressuredropwithinthegovernorhousingtozeropressurebecauseofthefullopenpositionofthereliefpoppetF FlowenteringthehousingthroughorificeCisdirectedtothetankpastthereliefpoppetwithoutincreasingthepressureinthehousing Thedeadheadpressureofthe40 gpmpumpthendecreasetothelowersetvalue 活塞完全从提升阀移开 这将由于减压阀处于全开位置 导致控制腔内更大的压力降 进入腔中的液压油经过C口和减压提升阀直接回到油箱而不会造成腔内压力的增加 40 gpm泵的空载压力值降低到低于设定值 41 Thusatthesettingoftheunloadinggovernor the40 gpmpumpgoestodeadhead Theflowratetothecircuitdecreasesto5 gpmasthepressureincreasesto1000psi At1000psi the5 gpmpumpisalsoatitsdeadheadsetting thusonlyholdingsystempressure 因此 在设定了卸载控制器的情况下 40gpm泵空载 随着回路压力增加到1000psi流量减少到5 gpm 在1000psi压力下 5 gpm泵也处于空载状态 仅仅维持着系统压力 42 在液压系统中 受到液体的运动类似于电力系统中的电流的运动 在电力系统里 通过电流运动来完成工作 液压系统也类似 Inafluid powersystem themovementofpressurizedfluidresemblestheactionofelectriccurrentinanelectricalsystem Insuchasystem electricalenergyiscontinuallymovingwhenworkisbeingdone Thesameistrueofafluid powersystem Paragraph1 43 在直流电力系统中 执行机构的速度可以通过改变流入执行元件的电流来改变 在交流电力系统中通过调节相应获得速度控制 液压系统中可通过不同控制方式来调节速度 气动系统由于气体的弹性改变 只可以得到相对粗的速度控制 Inadirect currentelectricalsystem thespeedofadeviceisvariedbychangingtheflowofcurrenttothedevice Alternating currentsyetem usephaseshiftingtoattainsimilarspeedcontrol Hydraulicsystemcanobtaininfinitespeedvariationsbyseveralmethodsofcontrol Pneumaticsystems becauseofthespringinessofthegas haverelativelycrudespeedcontrol Paragraph2 44 在液压系统中 我们可以对泵进行设计 以便利用泵的变量机构来改变所输出的高压液体的流量 从而使液压马达或其他装置获得不同的速度 Influid powersystems thepumpcanbedesignedsothedischargeflowofthepressurizedliquidcanbevariedbymanipulatingthepumpmechanism givingvaryingspeedsofthehydraulicmotororotheroutputdevice Paragraph3 45 利用泵出口管道的节流调节 可以按在直流电力系统相似的原理来控制液体流动 在需要时 液压系统可以利用阀来改变液体流向不同通道 获得速度控制 Arestrictionunthepumpoutletcanlimitthefluidflowinaignitionofthefluidbyhotfurnacesorotherhigh temperaturesurfaceswhenaleakoccurs Forthisreason fire resistanthydraulicfluidareoftenusedtoday 46 Thankyouforwacth