Priorities of Mold Design

Presentation on theme: "Priorities of Mold Design"— Presentation transcript:

1 Priorities of Mold Design
模具設計的優先順序 Priorities of Mold Design 澆注系統設計 (Filling System Design) 排氣系統設計 (Venting System Design) 冷卻系統設計 (Cooling System Design) 脫模系統設計 (Ejecting System Design)

2 Priorities of Filling System Design
澆注系統設計的優先順序 Priorities of Filling System Design 產品設計 (Part Design) 型腔設計 (Cavity Design) 澆口設計 (Gate Design) 流道設計 (Runner Design) 噴嘴設計 (Nozzle Design)

3 Typical Filling System
典型的澆注系統 Typical Filling System 豎澆道 Sprue 主流道 Main Runner 成品 Part 澆口 Gate 冷料井 Cold Slug Well 支流道 Branch Runner

4 壁厚不均 Non-uniform Wall Thickness
壁厚不均是注塑成型中最大的麻煩製造者。 這對薄壁產品尤然。 這些麻煩包括了遲滯現象、短射、凹陷、發赤、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-uniform wall thickness is the biggest trouble maker in plastic injection molding. This is especially true to thin-wall part. The troubles, including hesitation, short shot, sink mark, blush, jetting, warpage and long cooling time etc., can be predicted, directly or indirectly, by using CAE.

5 壁厚設計 Wall Thickness Design 差 [Poor] 較好 [Better] 最好 [Best]

6 掏空設計 (1) Coring Out Design (1) 改進設計 [Improved] 原設計 [Original]

7 掏空設計 (2) Coring Out Design (2) 差 [Poor] 改進 [Improved]

8 Void or/and Sink Mark Forming
氣泡或/和凹陷的形成 Void or/and Sink Mark Forming 氣泡 ( Void ) 凹陷 ( Sink Mark )

9 The Effect of Rib Thickness & Fillet Radius
肋厚和內圓角半徑的影響 The Effect of Rib Thickness & Fillet Radius

10 Bottom Thickness of Rib
肋的底部厚度 Bottom Thickness of Rib W 0.5W 2.5W 1.2WD 1.5WD (A) (B)

11 肋的設計 (1 ) Rib Design ( 1 ) t = wall thichness B = 0.5t C = 3 t A
D = 2 B E = 0.13 mm(radius) F = deg 假如需要更大的強度,可增加肋的數目 If more strength is required, add additional ribs. F B D E C t

12 肋的設計 (2) Rib Design ( 2 )

13 肋的設計 (3) Rib Design ( 3 )

14 Boss at Wall ( Thermoplastics )
與側壁相連之凸轂 (熱塑性塑膠) Boss at Wall ( Thermoplastics ) A = 凸轂附著處壁厚 wall thickness B = 凸轂外環直徑 dia. of boss over radii C = 0.5 A D = 2 B E = 1 ~ 2 deg F = 0.13 mm ( radius ) G = D H = 0.8 A I = A / 4 J = 2 B K = 0.3 ~ 1 J L = 0.5 A L H A' K E I G J D A F C B Section A'-A'

15 Boss Away From Wall ( Thermoplastics )
遠離側壁之凸轂 (熱塑性塑膠) Boss Away From Wall ( Thermoplastics ) A =凸轂附著處壁厚 wall thickness B =凸轂外環直徑 (含底部修整圓弧半徑) dia. of boss over radii C = 0.5 A D = 2 B E = deg F = 0.13 mm ( radius ) G = 0.95 D H = 0.3 G min. to G max. I = 0.5 A H E F D G C B A I

16 外側凸轂 Outside Boss A' A ( DIA ) B B = A B= 2A ( max. ) Section A'-A'

17 撓曲剛性 Flexural Rigidity
Where 1/r : 樑的曲率 curvature of the beam M : 彎曲力矩 bending moment E : 彈性模數 modulus of elasticity I : 斷面積對中立軸的慣性矩 moment of inertia of the cross- sectional area with respect to the neutral axis EI : 撓曲剛性 flexural rigidity

18 各種一體成型的內鎖件 能增加薄殼的剛性。 A variety of molded-in interlocks can add stiffness to thin-wall housing designs.

19 Structural Design & Thin-wall Molding Parts
結構設計和薄殼成型產品 Structural Design & Thin-wall Molding Parts 結構設計是薄殼成型零件的基礎。 Structural design is the base of thin-wall molding parts. 薄殼成型產品不僅僅是一趨勢，而且也是降低成本和提高競爭力的有效途徑。 Thin-wall molding part is not only a trend but also an effective way to achieve cost reduction and competitiveness increase.

20 Melt-Front Advancement
熔膠波前推進 Melt-Front Advancement 充填模式,積風和熔接線 Filling Patterns, Air-Traps and Weld Lines Location

21 熔接線 Weld Lines

22 Weld Lines Can Be Relocated By Changing Gate Location
更改澆口位置以重新定位熔接線 Weld Lines Can Be Relocated By Changing Gate Location 原設計 [Original] 更改設計 [Revised] 材料 [Material] : PC-GF50

23 Typical Butt Weld Tensile Strength Retention Values
典型對頭熔接線伸張強度保留值 Typical Butt Weld Tensile Strength Retention Values

24 熔接線冷料井 Weld Slug Well 熔接線冷料井 [Weld slug well] 對頭熔接線 [Butt weld]

25 積風 Air Traps

26 排氣 Vent 大部份熱塑性塑膠 耐隆和聚縮醛 ( POM ) A D B SEC. A'-A' C A'
Most Thermoplastics A mm B mm C mm D mm 耐隆和聚縮醛 ( POM ) Nylon and Acetal ( POM ) A mm 進料流道 Feed Runner 塑膠成品 Plastic Part A D 排氣孔 Vent B SEC. A'-A' C A'

27 澆口數目 The Number of Gates
每增加一個澆口，至少增加一條熔接線，同時增加一個澆口痕跡、增加流道的體積以及增加較多的積風。 Every time one gate is added, one weld line, at least, one gate mark, more runner volume and more air traps will be added. 在型腔能夠完滿充填的前提下，澆口數目是愈少愈好。 As long as the cavity is able to be filled appropriately, gates are the less the better. 為了減少澆口數目，每一澆口應就塑流力所能及的流長/壁厚比之內，找出可以涵蓋最大產品面積的進澆位置。 In order to reduce the number of gates, each gate shall be located at where the melt is able to cover maximum part area based on the largest melt flow length/thickness ratio.

28 充填均衡 Flow Balance 熔膠波前於同一時間抵達型腔各末端。
Melt front reaches the ends of cavity at the same time.

29 洗衣機圈板

30 洗衣機圈板

31 Air-conditioner Grille - Original
冷氣通風飾罩-原始設計 Air-conditioner Grille - Original 18 gates pressure: 76 MPa

32 Air-conditioner Grille - Revised
冷氣通風飾罩-修正設計 Air-conditioner Grille - Revised 8 gates pressure: 75 MPa

33 Comparison of Analysis Results
分析結果比較表 Comparison of Analysis Results

34 十二澆口設計 12 Gate Design 原始設計 Original Design 電子零件置物箱 材料 Material：ABS

35 四澆口設計 4 Gate Design 修正設計 Revised Design 電子零件置物箱 材料 Material：ABS

36 電子零件置物箱四澆口 和十二澆口設計比較表

37 如何快速平衡眾多模穴之流道 How to Balance Flow In A Multi-cavity Mold
首先調整一排支流道內之次支流道尺寸，使此支流道內之各模穴可平衡充填。 First, adjust runner size in one branch to make flow balanced in this branch. 再調整各支流道前段之尺寸，使各支流道可平衡充填。 Then, adjust the first section’s runner size in each branch to make flow balanced in all branches.

38 Unbalanced Flow In A Branch
一排支流道之不平衡充填 Unbalanced Flow In A Branch

39 Balanced Flow In A Branch
一排支流道平衡後之充填 Balanced Flow In A Branch

40 Unbalanced Flow In A Mold
全模具(128模穴)之不平衡充填 Unbalanced Flow In A Mold

41 全模具(128模穴)平衡後之充填 Balanced Flow In A Mold

42 The melt fills the inside cavities before filling the outside cavities.

43 The runner system shows that warmer, low-viscosity material (yellow and red) follows the inside wall when the melt splits at an intersection.

44 Melt ” Flipper ”

45 Gate Design for Flat Part
導致平直產品的澆口設計 Gate Design for Flat Part 中心澆口 Center Gate 扇形澆口 Fan Gate 最壞的 Worst 壞的 Worse 較好的 Better 最好的 Best 側澆口 Edge Gate 薄模澆口 Film Gate

46 Gate Design to Avoid Hesitation
澆口設計(減少滯流效應) Gate Design to Avoid Hesitation 澆口 gate 薄 thin 厚 thick 差的設計 Poor 好的設計 Good

47 幫浦零件 (Part, Pump) 塑料 (Polymer) : POM 公稱厚度 3.2 mm

48 幫浦零件 (Part, Pump) 塑料 (Polymer): POM 沒有遲滯現象

49 Gate Design to Avoid Sink Mark & Void
澆口設計(避免凹陷和氣泡) Gate Design to Avoid Sink Mark & Void 澆口 gate 差的 Poor 好的 Good

50 Avoid Jetting by Using Overlap Gate
使用重疊澆口以避免噴流 Avoid Jetting by Using Overlap Gate 差的 Poor 好的 Good

51 Avoid Jetting by Locating Gate Correctly
正確的澆口位置以避免噴流 Avoid Jetting by Locating Gate Correctly 差的 Poor 好的 Good

52 Avoid Jetting by Using Tab Gate
使用凸片澆口以避免噴流 Avoid Jetting by Using Tab Gate

53 Avoid Jetting by Profiling Gate Properly
使用適當的澆口形狀以避免噴流 Avoid Jetting by Profiling Gate Properly 差的 Poor 好的 Good

54 幫浦零件(Part, Pump) 塑料(Polymer): POM 進澆處(Polymer entrance)： 澆口厚(Gate thickness) 1.2mm，模穴厚(Cavity thickness) 3.2mm 問題 (Problem)： 噴流(Jetting)

55 Poor Design Causing Jetting
Part : Handle, Refrigerator Material : ABS Problem : Jetting Mark Gas Pin Gate

56 氣輔成型冰箱把手 澆口及氣針入口 澆口太小,導致噴流痕產生 厚度差異過大,導致二次噴流痕產生
R角過小,氣體通路接近把手內側,外側則因體積收縮造成凹陷痕跡

57 閥澆口 Valve Gate 1. 閥澆口梢 Valve-Gate Pin 2. 加熱管 Heater 3. O型環
2. 加熱管 Heater 3. O型環 #610 "0" Ring 4. 流道歧管模板 Manifold Plate 5. 軸封環 Seal Retainer 6. 套筒軸封 Sleeve Seal 7. 枕塊 Support Pillar 8. 油壓缸 Hydraulic Cylinder

58 閥澆口 (1) Valve Gate ( 1 ) 全部閥澆口同時打開時之充填狀況
Mold filling with all the valve gates ( shut-off gates ) opened at the same time.

59 閥澆口 (2) Valve Gate ( 2 ) 部份閥澆口延遲打開，改變充填模式
Mold filling with delayed valve gate opening; filling pattern, weld lines and air traps are changed.

60 多澆口設計 Multi-Gate Design

61 閥式澆口 Valve Gate

62 澆口種類 Gate Types 針點澆口 Pin Gate 扇型澆口 Fan Gate 潛伏澆口 Submarine Gate
邊緣(薄膜)澆口 Edge ( Film ) Gate 凸片澆口 Tab Gate 閥澆口 Valve Gate 環狀澆口 Ring Gate

63 Rectangular Edge Gate Design
矩形邊緣澆口設計 Rectangular Edge Gate Design L = 0.5 ~ mm W = 澆口寬度 ( mm ) gate width in mm A = 型腔表面積 ( mm ) surface area of cavity in mm2 n = 材料常數 material constant 0.6 for PE, PS 0.7 for POM, PC, PP 0.8 for CA, PMMA, PA 0.9 for PVC h = n t h = 澆口厚度( gate thick. in mm ) t = 零件壁厚( wall thick. in mm ) W t L h

64 扇形澆口設計 Fan Gate Design L= 1.3mm W= w= 澆口寬度 [mm] gate width in mm
A= 型腔表面積 [ mm2 ] surface area of cavity in mm2 n= 材料常數[ material constant ] 0.6 for PE, PS 0.7 for POM, PC, PP 0.8 for CA, PMMA, PA 0.9 for PVC 澆口厚度[ gate thick. in mm] t= 零件壁厚[ wall thick. in mm ] h1 = n t h2 = wh1/D

65 重疊式澆口設計 Overlap Gate Design W= w= 澆口寬度 [mm] gate width in mm
A= 型腔表面積 [ mm2 ] surface area of cavity in mm2 n= 材料常數[ material constant ] 0.6 for PE, PS 0.7 for POM, PC, PP 0.8 for CA, PMMA, PA 0.9 for PVC 澆口厚度[ gate thick. in mm] = nt 澆口長度[ land length in mm ] t= 零件壁厚[ wall thick. in mm ] L1 = 0.5~0.75 L2 = h+( w/2 )

66 凸耳澆口設計 Tab Gate Design L= 0.5~0.75mm W= w= 澆口寬度 [mm] gate width in mm
A= 型腔表面積 [ mm2 ] surface area of cavity in mm2 n= 材料常數[ material constant ] 0.6 for PE, PS 0.7 for POM, PC, PP 0.8 for CA, PMMA, PA 0.9 for PVC 澆口厚度[ gate thick. in mm] t= 零件壁厚[ wall thick. in mm ] h1 = n t h2 = 0.9 t

67 針點澆口設計 Pin Gate Design L = 0.5 ~ 0.75 mm d = 澆口直徑( mm )
gate diameter in mm t = 零件壁厚( mm ) wall thick. in mm A = 型腔表面積 ( mm2 ) surface area of cavity in mm2 n = 材料常數 material constant 0.6 for PE, PS 0.7 for POM, PC, PP 0.8 for CA, PMMA, PA 0.9 for PVC d L t

68 潛伏式澆口設計 Subgate Design W= w= 澆口寬度 [mm] gate width in mm
A= 型腔表面積 [ mm2 ] surface area of cavity in mm2 n= 材料常數[ material constant ] 0.6 for PE, PS 0.7 for POM, PC, PP 0.8 for CA, PMMA, PA 0.9 for PVC 澆口厚度[ gate thick. in mm] = nt t= 零件壁厚[ wall thick. in mm ] 30 ~ 15º ~ 25º

69 剪切速率 Shear Rate

70 剪切應力 Shear Stress 剪 切 應 力 shear Stress 黏 度 viscosity 剪 切 速 率
剪 切 應 力 shear Stress 黏 度 viscosity 剪 切 速 率 shear rate

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75 水力直徑 Hydraulic Diameter Where is the hydraulic diameter 水力直徑
A is the cross-sectional area of the flow 流路斷面積 P is the wetted perimeter 濕周長

76 水力直徑 Hydraulic Diameter
在不同剖面形狀，相同斷面積下之變化 Various runner profiles, based on the same cross-sectional area

77 流道尺寸設計 (1) Runner Sizing (1)
D : 流道直徑 ( mm ) runner diameter in mm W : 下游塑膠重量 ( g ) downstream plastic weight L : 流道長度 ( mm ) runner length in mm

78 流道尺寸設計 (2) Runner Sizing (2)

79 流道尺寸設計 (3) Runner Sizing (3)

80 流道尺寸設計 (4) Runner Sizing (4)

81 流道尺寸設計(A1) Runner Sizing (A1)
G( g ) D' ( mm ) for PS, ABS, SAN, CAB G : 重量 weight S : 零件厚度 thickness D' : 參考直徑 reference diameter

82 流道尺寸設計(A2) Runner Sizing (A2)
G( g ) D' ( mm ) for PE, PP, PA, POM G : 重量 weight S : 零件厚度 thickness D' : 參考直徑 reference diameter

83 流道尺寸設計(B) Runner Sizing (B)
fL L (mm) D = D' ‧fL D' : 參考直徑 reference diameter L : 長度 length fL : 長度係數 Length coefficient D : 流道直徑 runner diameter

84 冷料井設計 Cold Slug Well Design 2d 次流道 澆口 d 主流道 型腔 Secondary runner Gate
Primary runner 澆口 Gate 型腔 Cavity

85 slug-well sprue puller
冷料井設計 Cold Slug Well Design 倒椎度冷料井 豎澆道拉料桿 Reverse taper cold slug-well sprue puller Z型冷料井 " Z "- taper cold 溝型冷料井 Grooved cold

86 澆道襯套尺寸 Sprue Bushing Sizing