外文翻譯外文原稿LessonOneRunnerSystemInthischapter,youwilllearnaboutthefunctions,characteristics,andshapesofthesprue,runner,andgate.Themoltenplasticinjectedfromtheinjectornozzlewillgothroughasprue(spruebush),arunner,andagateandfillupinthecavity.Asthetemperatureofmoltenplasticisloweredwhilegoingthroughthesprueandrunner,theviscositywillrise；therefore,theviscosityisloweredbyshearheatgeneratedwhengoingthroughthegatetofillthecavity.SprueAsprueisachannelthroughwhichtotransfermoltenplasticinjectedfromthenozzleoftheinjectorintothemold.Itisapartofspruebush,whichisaseparatepartfromthemold.RunnerArunnerisachannelthatguidesmoltenplasticintothecavityofamold.GateAgateisanentrancethroughwhichmoltenplasticentersthecavity.Thesprue,therunner,andthegatewillbediscardedafterapartiscomplete.However,therunnerandthegateareimportantitemsthataffectthequalityorthecostofparts.GateThegateiscategorizedintorestrictivegate,whichnarrowstheentrance,andnonrestrictivegate,whichdoesnotnarrowtheentrance.Thegatehasthefollowingfunctions:Restrictstheflowandthedirectionofmoltenplastic.Simplifiescuttingofarunnerandmoldingstosimplifyfinishingofparts.Quicklycoolsandsolidifiestoavoidbackflowaftermoltenplastichasfilledupinthecavity.RestrictiveGateArestrictivegatehasanarrowentrancetothecavitytorestricttheamountofmoltenplasticinordertoimprovefillinginthecavity.Therestrictivegatehasthefollowingcharacteristics.oGeneratesshearheatbygoingthroughthenarrowgate,raisingthetemperatureofmoltenplasticandimprovingthefillinginthecavity.oReducesresidualstress,andthusreducespartdefectsuchaswarp.oAsthecoolingsolidificationtimeisshortened,moldingcycleisalsoshortened.oAsthegatetraceisless,itispossibletocompletefinishingprocessinashorttime.Therestrictivegatehasthefollowingtypes.SideGateSubmarineGate(TunnelGate)Themostcommongate.Puttothesideofparts.Thegatetracewillbeleft.Oftenusedforthestructurewithmorethantwocavities.Thegatewillbeautomaticallycutoffduringmoldopening.Thepositionisflexible(front,side,orbackofparts).Thegateneedstobethoughtaboutnottobeleftinsidethecavity.PinPointGateFanGateSuitableformoldingmultipleparts.Thepositionisrelativelyflexible.Thestructureiscomplicatedduetothreeplatemethodofdie.Suitableforlargeandflatplateparts.Finishingisdifficultandcostishighduetothewidegate.Thegatetracewillbeleft.FilmGateValveGateSuitableforthinplateparts.Finishingisdifficultandcostishighduetothewidegate.Thegatetr