搜索
1西南交通大学本科毕业设计（论文）外文资料及翻译年级:2007级学号:20077657姓名:王雪扬专业:工程机械指导老师:李春林2011年5月2LoadingmachinesFormaterialshandinginconstruction,useismadeofloaders.Practicehasshownthatexcavatorsarelesseffectiveinthecapacityofloadsinquarriesandstoragesofnonmetallicmaterialsthanloaders.Bythekindofloadshandled,loadersareclassifiedasforkliftloadsandscoopingloadersforloosematerials.Soopingloadersaredividedintosingle-bucketandcontinuous-actionMulti-bucketloaders.Single-bucketloadersaregeneral-purposemachinessuitedengineeringandinapplicationsrequringcontinuousworkingprocess.Dependingonthekindofrunninggear,crawlerandanailable.Crawlerloadershaveahighpassblibityanddevelopagreatthrustefftort.Wheeledloadersfeatureahighmanoeuvrabilityandhightravelingspeedsmakingnodamagetotheroadpavementandthestorageareas.Unloadersareusedforunloadingsand,gravel,crushedstone,cementformrailwaycars.Powerandpneumaticunloadersareused,powerforunloadingmaterialsfromflatcarsorgondolacars(openwagons)andpneumaticforunloadingcement.Themainworkingmemberoffork-liftloadersistheforkservingtoloadandunloadpieceloads.Theseloadershavedifferentchangeattachments.Whenequippedwithbucketsorgrabs,theyareusedforloadinglooseandsmall-piecematerials,andtheboomattachmentmakestheseloaderssuitedforhoistingloadstoasmallheigheandsometimesforerectionworkinconstruction.Fork-liftloadersareoperatedonhard-pavementareas,thereforetheyaremainlyusedinstorehouseandasfactorymaterials-handingequipment.Theyaremadeonthebasisofatruckthereforetheyarealsocalledtruckloaders.theyarepoweredbyinternalcombustionenginesorelectricmotorswithstoragebatteries.Enginepoweredtruckareusedforlargewarehouseandstock-handingapplication,forgeneralyardworkandfprloadingandunloadingofvehicles.Torqueconvertertransmissionprovidessmoothoperation;powersteeringandall-weathercabsareoptionsavailable.3Single-bucketloadershaveacrawlertractororawheeledtruckasacarriermounting.Theloaderpermitsmechanizationofloadingconstructionanderectionandworkwiththeaidofchangeattachments,ofwhichthemainoneisthebucket.Theloadingequipmentisavailableinthreemodifications:front-end,overloading,andhalf-swing,jib-type.Thefront-endattachmentprovidesalsosideunloading.Theoverloadingmodifiactaionpermitsbackunloading.Presentlyfront-endloaderwiththepositivedisplacementhydraulicdrivesfortheattachmentaremostwidelyused.Theoutputofmulti-bucketloadersis40to60percenthigherthanofsingle-bucketmachinesatthesamepowerrating,itisexpedienttousetheminbrickyards,prefabricatedconcreteproductsplants,railwaystationswithlargevolumesofloading-unloadingoperatinsandalsoforloadingloosematerials.Inaddition,theyaresuitedforsizegradingofloosematerials,forwhichpurposetheyareprovidedwithspecialvibratingscreens.Multi-bucketloadersareveryefficientinunloadingflatcarswithsidedumpingofthehandlematerial.Theseloaderscanbeappliedintheproductionlinesofprefabricatdeainstructionproductsplantsandalsoinroadbuilding.Inthelattercasetheyareusedforloadingsandandgravelintodryingdrumsandmixers.Theworkingmemberoftheloaderisascrewfeederconsistingoftowright-handandleft-handscrews,whicharearrangedonbothsidesofabucketelecator.Whenthefeederrotates,theloadedmaterialisdeliveredtothebucketstomakethescoopingeasier.Ascraperissecuredunderneaththescrewfeeder.Theelevatorofthemulti-bucketloaderusuallydischangesthematerialontobeltconveyersthatdeliverittotiansportfacilities.Someloadersdischargethehandlematerialintotranportfacilitiesthroughhoppersorchutes.4装载机在建筑施工中，材料的装卸是用装载机和写在机进行的。实践证明，在采石场和非金属材料的仓库作业中，挖掘机的装在效率要比装载机高。根据所装载材料的种类，装载机可以分为叉式装载机，用于装在整块物料；铲斗式装载机，用于装载松散物料。铲斗装载机分为单斗装载机和连续作业多斗装载机。单斗装载机式通用机械，适用于多种条件下作业。多斗装载机用于大型仓库、公路工程以及需要连续作业的工作。按照行走装置的类型，可以分为履带行走装载机和轮胎式装载机。履带行走式装载机具有良好的通过性，能产生很大的推进力。轮胎装载机机动性能良好。行走速度快，对公路路面和存活地面从不产生破坏作用。装载机用来卸掉火车车厢里的砂子、砾石、碎石和水泥。卸载机分为机动卸载和气动卸载机。既定卸载机用于从平板货车或敞蓬车上卸货；气动卸载机用于卸水泥。叉车的主要工作装置是用于装卸整件货物的叉子。这些装载机有不同的换装部件。当装上铲斗或抓斗时，可用语装卸松散和小块物料，叉架机构使这些装载机能适于把货物举升到一个不大的高度，有时也适于建筑安装工程。因为叉车在硬路面上作业，因此，主要用于仓库并作为工厂物料的装卸设备。这些装载机是根据卡车的原理制造的，所以也叫卡车装载机，他们以内燃机或带有蓄电池的电动机为动力。以发动机为动力的卡车用于大型仓库和材料搬运工作，用于一般的堆放场和车辆装卸。液力变距传动系统使运动平稳。还可以选配动力转向及全天候驾驶室。单斗装载机以履带拖拉机或轮胎拖拉机作为行走机架。该装载机可使装载作业、建筑施工、安装工程实现机械化。在这些换装装置中，主要附件是铲斗。装载设备有三种不同的形式，即前卸式、翻转式和侧卸式。前卸式机构只允许从装料的一侧卸料；侧卸式机构是侧面卸料；翻转式机构则从后面卸料。目前，具有变量液压驱动的工作装置的前卸式装载机使用得最为广泛。多斗装载机的产量比同一额定功率的单斗装载机的产量高40%~60%。多斗装载机适于砖厂、混泥土预制品厂及装卸量大的火车站，也同样适用于装载松散5物料。此外，该机还适用于对松散物料的颗粒分级，为此，可以安装一个专用的振动筛。用多斗装载机为侧边卸料的平板车卸料，其效率很高。多斗装载机可用于混凝土预制品厂的生产线中，也可用于筑路。在筑路中，用于将砂子和砾石装入烘干筒和搅拌机里。该装载机的工作机构是两个左右螺旋杆组成的螺旋给料器，安装在斗式提升机的两侧。当给料器旋转时，物料被送入各个铲斗内，使得装料比较容易。刮板固定在螺旋给料器的下方。多斗装载机的提升机把物料卸在传送带上，再由传送带将物料运送到设备中。有些装载机用漏斗或料槽把物料送进运输设备中。PneumaticMotorsandToolsCompressdeaircanbeusedforawidevarietyofoperations,suchas:todriveairmotorsandairhammers,tooperateaircylinders,toatomizeliquids,toconverymaterials,todisplaceandagitateliquids,toserveasacushion,tocreateavacuum,toacceleratecombustion,andtoserveasacoolantandlubricant.Anelectricmotorisadeviceinwhichelectricalenergyisconvertedintomechanicalenergy.Afluidmotorisadeviceforconvertingfulidenergyintomechanicalenergy.Inthischapter,themainfeaturesofpneumaticmotorsandpneumatictoolsarediscussed.GENERALTYPESOFAIRMO