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1、模具設計的優(yōu)先順序PrioritiesofMoldDesign澆注系統(tǒng)設計(FillingSystemDesign)排氣系統(tǒng)設計(VentingSystemDesign)冷卻系統(tǒng)設計(CoolingSystemDesign)脫模系統(tǒng)設計(EjectingSystemDesign)澆注系統(tǒng)設計的優(yōu)先順序PrioritiesofFillingSystemDesign產(chǎn)品設計(PartDesign)型腔設計(CavityDesign)澆口設計(GateDesign)流道設計(RunnerDesign)噴嘴設計(NozzleDesign)豎澆道Sprue主流道MainRunner
2、成品Part澆口Gate冷料井ColdSlugWell支流道BranchRunner典型的澆注系統(tǒng)TypicalFillingSystem壁厚不均是注塑成型中最大的麻煩製造者。這對薄壁產(chǎn)品尤然。這些麻煩包括了遲滯現(xiàn)象、短射、凹陷、發(fā)赤、噴流、翹曲及長冷卻時間等;目前都可用CAE以直接或間接的方式預測。Non-uniformwallthicknessisthebiggesttroublemakerinplasticinjectionmolding.Thisisespeciallytruetothin-wallpart.Thetroubles,includinghesitat
3、ion,shortshot,sinkmark,blush,jetting,warpageandlongcoolingtimeetc.,canbepredicted,directlyorindirectly,byusingCAE.壁厚不均Non-uniformWallThickness壁厚設計WallThicknessDesign差[Poor]較好[Better]最好[Best]掏空設計(1)CoringOutDesign(1)改進設計[Improved]原設計[Original]差[Poor]改進[Improved]掏空設計(2)CoringOutDesign(2)氣泡或
4、/和凹陷的形成Voidor/andSinkMarkForming氣泡(Void)凹陷(SinkMark)肋厚和內(nèi)圓角半徑的影響TheEffectofRibThickness&FilletRadius肋的底部厚度BottomThicknessofRibW0.5W2.5WW1.2WD1.5WD(A)(B)肋的設計(1)RibDesign(1)t=wallthichnessB=0.5tC=3tAAD=2BE=0.13mm(radius)F=1.5-2deg假如需要更大的強度,可增加肋的數(shù)目Ifmorestrengthisrequired,addadditionalribs.FB
5、DECt肋的設計(2)RibDesign(2)肋的設計(3)RibDesign(3)與側壁相連之凸轂(熱塑性塑膠)BossatWall(Thermoplastics)A=凸轂附著處壁厚wallthicknessB=凸轂外環(huán)直徑dia.ofbossoverradiiC=0.5AD=2BE=1~2degF=0.13mm(radius)G=DH=0.8AI=A/4J=2BK=0.3~1JL=0.5ALHA'A'KEIGJDAFCBSectionA'-A'遠離側壁之凸轂(熱塑性塑膠)BossAwayFromWall(Thermoplastics)A=凸轂附著處壁厚wallthic
6、knessB=凸轂外環(huán)直徑(含底部修整圓弧半徑)dia.ofbossoverradiiC=0.5AD=2BE=1-2degF=0.13mm(radius)G=0.95DH=0.3Gmin.toGmax.I=0.5AHEFDFGCBAI外側凸轂OutsideBossA'A'A(DIA)BB=AB=2A(max.)SectionA'-A'Where1/r:樑的曲率curvatureofthebeamM:彎曲力矩bendingmomentE:彈性模數(shù)modulusofelasticityI:斷面積對中立軸的慣性矩momentofinertiaofthecross-section
7、alareawithrespecttotheneutralaxisEI:撓曲剛性flexuralrigidity撓曲剛性FlexuralRigidityAvarietyofmolded-ininterlockscanaddstiffnesstothin-wallhousingdesigns.各種一體成型的內(nèi)鎖件能增加薄殼的剛性。結構設計是薄殼成型零件的基礎。Structuraldesignisthebaseofthin-wallmoldingparts.薄殼成型產(chǎn)品不僅僅是一趨勢,而且也是降低成本和提高競爭力的有效途徑。Thi