模具冷却设计.ppt

模具冷卻設計的目的,Purposes of Mold Cooling Design,1.,均衡冷卻(改良產品品質),Even Cooling(Improve Part Quality),2.,有效冷卻(提高生產力),Efficient Cooling(Increase Productivity),薄殼產品不像傳統壁厚者,一般,可以承受較大的,因,熱傳不均而產生的殘餘應力,。為了將收縮彎翹控制在可以接受的程度，均衡的冷卻設計變得非常重要。,Thin-wall part can not afford as much thermal induced residual stress as the conventional one does.An even cooling design becomes very important to control the shrinkage and,warpage,at an acceptable level.,冷卻設計,Cooling Design,射出成型週期時間,Injection Molding Cycle Time,充填時間,Fill Time,開模時間,Open Time,後充填時間,Post-fill Time,對冰箱蔬果盤之類的大零件而言,，,材料往往佔成本,50%,以上,。對小而薄,的零件而言,，成形機費用可佔成本的90%，材料6%，而模具只佔4%。,小而薄的產品較之厚者更能從冷卻的改善而獲得效益,。,For larger molded parts,material typically represents more than 50%of the part cost for a refrigerator crisper tray.In the case of a thin-wall small part,the press cost could be 90%of the cost of the part;material constitutes 6%and the mold only 4%of the cost of each part.Small thin-wall parts typically benefit from improved cooling more than thick parts.,冷卻設計,Cooling Design,典型的冷卻系統,Typical Cooling System,模溫調節機,Temperature controlling unit,軟管,Hoses,冷卻迴路 2,Cooling Circuit 2,冷卻迴路 1,Cooling Circuit 1,泵,Pump,收集歧管,Collection manifold,供給歧管,Supply manifold,模具冷卻管路,Mold Schematic,冷卻孔道,Cooling Channels,入口,Inlet,出口,Outlet,入口,Inlet,出口,Outlet,噴泉管,Bubbler,障板管,Baffle,熱管,Heat Pipe,蒸發部位熱輸入,Heat In,凝結部位熱輸出,Heat Out,液體,Liquid,蒸汽,Vapor,燈心(毛細管),Wick (Capillary),熱管的應用,The Application Of Heat Pipe,理論上最短冷卻時間,Min.Possible Cooling Time,理論上最短冷卻時間,the min.possible cooling time,產品最大厚度,the max.part thickness,熔膠的熱擴散度,thermal diffusivity of the melt,射出溫度,injection temp.,冷卻液溫度,coolant temp.,頂出溫度,ejection temp.,冷卻時間和厚度分佈,Cooling Time and Thickness Profile,差的設計,Bad Design,好的設計,Good Design,冷卻孔道直徑、深度和節距建議值,Recommended Diameter,Depth&Pitch,D:,直徑為10至14,mm,Diameter of Cooling Channel,10 to 14 mm,d:,深度為,D,至,3,D,Depth,D,to 3D,P:,節距為,3,D,至,5,D,Pitch,3D to 5D,原始設計,Original Design,修正設計,Revised Design,A,A,SEC.A-A,原始設計,Original Design,母模板,Cavity Plate,澆道襯套,Sprue,Bushing,母模嵌塊,Cavity Insert,公模嵌塊,Core Insert,公模板,Core Plate,承板,Support Plate,修正設計,Revised Design,母模板,Cavity Plate,澆道襯套,Sprue,Bushing,母模嵌塊,Cavity Insert,公模嵌塊,Core Insert,公模板,Core Plate,承板,Support Plate,原始設計,Original Design,公模嵌塊,core insert,O,型環,O-ring,空氣囊,air pocket,修正設計(1),Revised Design(1),公模嵌塊,core insert,O,型環,O-ring,修正設計(2),Revised Design(2),公模嵌塊,core insert,O,型環,O-ring,不平衡的設計,Unbalanced Design,平衡的設計,Balanced Design,不用限流孔梢的內歧管設計,Internal Manifold Design without,Frop,s,使用限流孔梢的內歧管設計,Internal Manifold Design Utilizing,Frop,s,限流孔梢,Flow Resistance Orifice Pin,紊流和層流,Turbulent and Laminar Flows,紊流,Turbulent Flow,層流,Laminar Flow,雷諾數,Reynolds Number,雷諾數(無因次),Reynolds number(dimensionless),密度,density(g/cm3),直徑,diameter(cm),速度,velocity(cm/sec),黏度,viscosity(poise or dyne-sec/cm2 or g/cm-sec),Nu,對雷諾數(,Re),Nusselt,Number Vs.Reynolds Number,層流,Laminar,紊流,Turbulent,差的設計,Poor Design,好的設計,Better Design,差的設計,Poor Design,好的設計,Better Design,差的設計,Poor Design,好的設計,Better Design,冷卻設計原則,Cooling Design Principles,選擇熱擴散係數大的塑料。,Select Plastic Material with large thermal diffusivity.,採用薄而均一的製件厚度。,Use a thin and uniform part thickness.,在型腔周圍均衡的配置冷卻孔道。,Layout cooling channels around cavities evenly.,在熱傳的道路上移除空氣間隙和空氣囊。,Remove air gaps and pockets from heat transfer path.,平衡冷卻液流動。,Balance coolant flow.,檢查冷卻效率。,Check cooling efficiency.,促使冷卻勻稱。,Make cooling evenly.,選擇適當設備。,Select appropriate equipment.,