Chapter3MachineryandEquipmentforDirect/IndirectHotExtrusionTHEMACHINERYANDEQUIPMENTrequiredforrod（杆，棒，竿）andtubeextrusionisdeterminedbythespecificextrusionprocess.Ideally,themachineryandequipmentshouldhaveflexibilitybut,also,providespecificextrusionprocesswiththeoptimum（最适宜的）qualityandeconomicefficiency.Directhotextrusionisthemostwidelyusedprocess,andthetermextrusionusuallyreferstothisprocess.Themachineryusedisusuallybasedonso-calledstandarddesigns.Theotherextrusionprocessesusuallyrequirespeciallydevelopedmachines.Theyaredesignedaccordinglyandbuilttomeettheneedsoftheoperator.注释：rod[rɔd]杆，棒，竿optimum['ɔptiməm]最适宜的3.1MachineryforDirectExtrusionThedesignofadirect-extrusionpressisdeterminedbythefollowingfactors：●Producta.Aluminumandaluminumalloys(lightmetal)easytoextrudeand/ordifficulttoextrude.Wire（金属丝制的；金属网制的）,bar（木、金属等的条）,section,hollowsection,andwideflatsectionsb.Copper（铜）andcopperalloysincludingbrass（黄铜）(heavymetal)easytoextrudeand/ordifficulttoextrude.Wire,bar,andsectionc.Steelandhigh-strengthsteelalloyseasytoextrudeand/ordifficulttoextrude.●Processtechnologya.Extrusionwithoutlubrication（润滑）andwithoutashell（壳）b.Extrusionwithoutlubricationandwithashellc.Extrusionwithlubricationwithoutashell●Toolinga.Container（挤压筒）,stem（杆）,dummyblock（挤压垫）,anddieThewiderangeofdifferentdesignsforextrusionpresseshasrecentlybeenreducedinmostextrusionplantstoafewhigh-output（高输出）types.Therefore,onlyextrusionpressdesignsthatdominate（主导）today’smarketarediscussedinthischapter.ThesearereferredtoasstandardextrusionpressesinTable3.1.Direct-extrusionpressesaccountformorethan95%ofthetotalvolumeofallpresses.Thedirect-extrusionpressisusedforallcurrentextrusionprocesses.Machinesforthedirecthotextrusionoflight-metalalloysaremainlyusedfortheextrusionofsection(80%),tube(10%),androd(<10%)inaluminumandaluminumalloys.Themachinesfordirecthotextrusionofheavymetals,mainlycopperandcopperalloys,areusedfortheextrusionofrod,wire,andsection(60%)(mainlyinbrass)andtube(40%)(mainlyincopper).Table3.1Pressesforthedirectextrusionofaluminumalloys(lightmetal),copperalloys(heavymetal),andsteelSteelandsteelalloysareonlyproducedbyextrusiontoalimitedextent（范围,程度）,andthenonlywhenrolling（滚压；轧制）isnotpossibleorthevolumesaretoosmall.Thefollowingmajorpointsmustbeconsideredintheconstructionofextrusionpresses:●Technologyrequirements:Thiscoversthemetallurgical（冶金的,冶金学的）aspectsofthedeformationtechnologyofextrusion.●Economicfactors:Theeconomicneedforrationalization（合理化）intheconstructionofextrusionpressesismostclearlyseeninaluminumextrusion.Newextrusionplantsarebuiltasintegrated（整合的）productionlines.Theyincludebilletstores,billetheating,extrusionpress,handlingequipmentwithlongitudinal（纵向的）andtransverse（横向的）conveyors（输送带）,sectioncoolingsystems,stretcher（拉伸机）,cut-to-lengthsaws（定长剪切锯床）andstackers（栈式存储器）,aswellasheattreatmentequipmentandpacking（包装）lines.Similardevelopmentscanbefoundinheavy-metalextrusionplants.Sophisticated（富有经验的；精致的；复杂的）systemsforelectronicdatacollectionanddataanalysisfortheeconomicoptimalproductionarealreadyconsideredtobestandard.注释：Wire['waiə]金属丝制的；金属网制的bar[bɑ:](木、金属等的)条Copper['kɔpə]铜brass[brɑ:s]黄铜lubrication[,lu:bri'keiʃ...
