慈溪市云升环保注塑外贸参考资料

1Dr.ApiwatMuttamaraOutline•Equipmentandprocesssteps•DesignforPart•Designformanufacturing,toolinganddefectsTHERMOPLASTIC,THERMOSET:•Thermoplasticsareresinsthatcanberegroundaftermolding,andmoldedagain.•ThermoplasticareoftencomparedtoWax.•Thermosetscanbemoldedonceonly;theytendtobedensermaterialsforspecialpurposes,thermosetsareoftencomparedtoanegg;oncetheeggishardboileditcan'tbereturnedtoaliquidandrecookedassunnysideup.PlasticsProcessing:InjectionMoldingMoldStructure:PartinglineAdividinglinebetweenacavityplateandacoreplateofamold.-Makeapartinglineonaflatorsimple-curvedsurfacesothatflashcannotbegenerated.-Ventinggasorair.TwoplatemoldOnepartinglineThreeplatemoldTwopartinglinesMeltDeliveryGate-Deliverstheflowofmoltenplastics.-Quicklycoolsandsolidifiestoavoidbackflowaftermoltenplasticshasfilledupinthecavity.-Easycuttingfromarunner-Locationisimportanttobalanceflowandorientationandtoavoiddefects.L=0.5-0.75mmh(thickness)=n.tW=nA1/230RunnercrosssectionRunnercrosssectionthatminimizesliquidresistanceandtemperaturereductionwhenmoltenplasticsflowsintothecavity.-Toobig-Longercoolingtime,morematerial,cost-Toosmall-shortshot,sinkmark,badquality-Toolong-pressuredrop,waste,coolingHotrunner,runnerlessmoldRunnerbalancingBalancedNotbalancedDefectsMoldingdefectsarecausedbyrelatedandcomplicatedreasonsasfollows:*Malfunctionsofmoldingmachine*Inappropriatemoldingconditions*Flawsinproductandmolddesign*ImproperSelectionofmoldingmaterialWeldlineThisisaphenomenonwhereathinlineiscreatedwhendifferentflowsofmoltenplasticsinamoldcavitymeetandremainundissolved.Itisaboundarybetweenflowscausedbyincompletedissolutionofmoltenplastics.Itoftendevelopsaroundthefaredgeofthegate.CauseLowtemperatureofthemoldcausesincompletedissolutionofthemoltenplastics.SolutionIncreaseinjectionspeedandraisethemoldtemperature.Lowerthemoltenplasticstemperatureandincreasetheinjectionpressure.Changethegatepositionandtheflowofmoltenplastics.Changethegatepositiontopreventdevelopmentofweldline.FlashesFlashesdevelopatthemoldpartinglineorejectorpininstallationpoint.Itisaphenomenonwheremoltenpolymersmearsoutandstickstothegap.CausePoorqualityofthemold.Themoltenpolymerhastoolowviscosity.Injectionpressureistoohigh,orclampingforceistooweak.SolutionAvoidingexcessivedifferenceinthicknessismosteffective.Slowdowntheinjectionspeed.Applywell-balancedpressuretothemoldtogetconsistentclampingforce,orincreasetheclampingforce.Enhancethesurfacequalityofthepartinglines,ejectorpinsandholes.ShortshotThisisthephenomenonwheremoltenplasticsdoesnotfillthemoldcavitycompletely.andtheportionofpartsbecomesincompleteshape.CauseTheshotvolumeorinjectionpressureisnotsufficient.Injectionspeedissoslowthatthemoltenplasticsbecomessolidbeforeitflowstotheendofthemold.SolutionApplyhigherinjectionpressure.Installairventordegassingdevice.Changetheshapeofthemoldorgatepositionforbetterflowoftheplastics.WarpageThisdeformationappearswhenthepartisremovedfromthemoldandpressureisreleased.CauseUnevenshrinkageduetothemoldtemperaturedifference(surfacetemperaturedifferenceatcavityandcore),andthethicknessdifferenceinthepart.Injectionpressurewastoolowandinsufficientpacking.SolutionTakealongercoolingtimeandlowertheejectionspeed.Adjusttheejectorpinpositionorenlargethedraftangle.Examinethepartthicknessordimension.Balancecoolinglines.Increasepackingpressure.Sinkmarks-Equalcoolingfromthesurface-Secondaryflow-CollapsedsurfaceSinkMarktsttstCAE(computeraidedengineering)ProcesssimulationMaterialdatabaseCADMOLDFLOWC-FlowConsiderationsindesignofinjectionmoldedpartsGuideline(3)gatelocationdeterminesweldlinesweldlines*Source::moldswithmovingcoresandside-actioncams-Ifthegeometryoftheparthasundercuts[definition?]MoldStructure:Undercut,SlidecoreDesigninginjectionmolds:typicalfeatures[source:](a)Shut-offhole:nosideactionrequired(b)Latch:nosideactionrequired(c)AngledLatch:Sideactioncamrequired(a)Shut-offhole:nosideactionrequired(b)Latch:nosideactionrequired(c)AngledLatch:SideactioncamrequiredDesigninginjectionmolds:typicalfeaturesDesignSteps•Ex.ABS=0.5%,PP=1-3%1.Plastic’sType-Shrinkage2.Partingline3.CoreCavity3.NumberofCavityEjectorsystemCoolingSystem