Purposes of Mold Cooling Design

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1 Purposes of Mold Cooling Design
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)

2 冷卻設計 Cooling Design 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.

3 Injection Molding Cycle Time
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

4 冷卻設計 Cooling Design 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.

5 Typical Cooling System
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

6 模具冷卻管路 Mold Schematic

7 冷卻孔道 Cooling Channels 入口 Inlet 出口 Outlet

8 噴泉管 Bubbler

9 障板管 Baffle

10 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 )

11 The Application Of Heat Pipe
熱管的應用 The Application Of Heat Pipe

12 Min. Possible Cooling Time
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.

13 Cooling Time and Thickness Profile
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

14 Recommended Diameter, Depth & Pitch
冷卻孔道直徑、深度和節距建議值 Recommended Diameter, Depth & Pitch D : 直徑為10至14mm Diameter of Cooling Channel, 10 to 14 mm d : 深度為D至3D Depth, D, to 3D P : 節距為3D至5D Pitch, 3D to 5D

15 原始設計 Original Design

16 修正設計 Revised Design A SEC. A-A

17 原始設計 Original Design 母模板 澆道襯套 Cavity Plate Sprue Bushing 母模嵌塊
Cavity Insert 公模嵌塊 Core Insert 公模板 Core Plate 承板 Support Plate

18 修正設計 Revised Design 母模板 澆道襯套 Cavity Plate Sprue Bushing 母模嵌塊
Cavity Insert 公模嵌塊 Core Insert 公模板 Core Plate 承板 Support Plate

19 原始設計 Original Design 公模嵌塊 core insert O型環 O-ring 空氣囊 air pocket

20 修正設計 (1) Revised Design ( 1 ) 公模嵌塊 core insert O型環 O-ring

21 修正設計 (2) Revised Design ( 2 ) 公模嵌塊 core insert O型環 O-ring

22 不平衡的設計 Unbalanced Design

23 平衡的設計 Balanced Design

24 Internal Manifold Design without Frop's
不用限流孔梢的內歧管設計 Internal Manifold Design without Frop's

25 Internal Manifold Design Utilizing Frop's
使用限流孔梢的內歧管設計 Internal Manifold Design Utilizing Frop's

26 Flow Resistance Orifice Pin
限流孔梢 Flow Resistance Orifice Pin

27 Turbulent and Laminar Flows
紊流和層流 Turbulent and Laminar Flows 紊流 Turbulent Flow 層流 Laminar Flow

28 雷諾數 Reynolds Number 雷諾數(無因次) 密度 直徑 速度 黏度
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)

29 Nusselt Number Vs. Reynolds Number
Nu對雷諾數(Re) Nusselt Number Vs. Reynolds Number 層流 Laminar 紊流 Turbulent

30 差的設計 Poor Design

31 好的設計 Better Design

32 差的設計 Poor Design

33 好的設計 Better Design

34 差的設計 Poor Design

35 好的設計 Better Design

36 Cooling Design Principles
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.