1. 20038
BATTERY COVER
David Deng
2005/05/29

2. Contents
Plastic Material Introduction
Product Model Introduction
Cooling System Design
Feed System Design
Analysis Indication
Processing Conditions
Analysis Results ~27
Conclusions & Suggestions

3. PP POLYPROPYLENES CM1171 Taiwan PP VI(245)84 OCT-08-2002 JUL93
Material introduction
PP POLYPROPYLENES CM Taiwan PP VI(245)84 OCT JUL93
1. Conductivity W/m/ deg.C Ejection temperature deg.C
2. Specific heat J/kg/ deg.C Min. melt temperature deg.C
3. Melt density kg/cu.m Max. melt temperature deg.C
4. Max. shear stress MPa Min. mold temperature deg.C
5.Max. shear rate /s Max. mold temperature deg.C

4. Product model introduction
Thickness distribution is not even. Min. wall thickness is about 0.64mm, Max. wall thickness is about 5.00mm. As shown below the plot, the blue is the thinner region, and the red is the thicker region(include injection and cooling system).
210 51 87
Max. contour dimension(mm)
Thickness distribution

5. Cooling System Design Cooing network Ø10
Cooling system have 20 circuits. Core have 12 circuits and cavity have 8 circuits.

6. Feed System Design Gate location 9 Ø 5 Gate Ø 8 Ø 4.15 16 2.2 124 2
The mold is cold feed system, two cavities, one banana gate. The dimension of the gate is shown in top plot.

7. Analysis Indication
Moldflow CAE analysis includes Flow,Cooling and Warp results,aimed to optimize the feed system, the cooling system of the mold.

8. Processing Conditions
Packing profile:
Filling Conditions:
MPa
Mold temperature: deg.C
Melt temperature: deg.C
Injection time ﹕ sec
Total Volume (cavity): cu.cm
Part Volume : cu.cm
Sprue/runner/gate volume: cu.cm
Total Weight : g
Runner Weight﹕ g
Circuit Inlet Temp : 25.0 deg.C 30 s
Pressure [MPa] Time [sec]
Cooling Conditions:

9. Best Gate Location Gate Analysis Results\
The best gate location lie in the marked region.
It is difficult to design mold, so can’t be accepted in fact.

10. Fill Time Flow Analysis Results\
Fill time is about 3.8sec, and the filling pattern is satisfied. The marked region is filled last.The below plot is the scene of filling 99%(V/P switch over).
Click for animation

11. Fill Time Flow Analysis Results\
Fill time is about 3.8sec, and the filling pattern is satisfied. The marked region is filled last.The below plot is the scene of filling 99%(V/P switch over).
Click for animation

12. Injection Pressure Flow Analysis Results\
Max. injection pressure is 33 Mpa (V/P switch over).

13. Injection Pressure Flow Analysis Results\
The pressure drop in runner system is about 24MPa, which is 72.7% of injection pressure.
The below plot is the pressure distribution of filling 99%(V/P switch over).

14. Flow Front Temperature
Flow Analysis Results\
Flow Front Temperature
Gate
The flow front temperature is from 221 to deg.C, and the distribution is not very uniform. The minimum temperature is shown in the marked region.Pay attention to the weldlines in this area.

15. Weld Lines Flow Analysis Results\
Main weld lines are shown as red lines.
Pay more attention to the weldlines in this area.
Gate

16. Air Traps Flow Analysis Results\
Air traps locations are shown by small pink balls. Most of them lie in the last filling or the interface area, so can be vented easily.
Gate

17. Sink Index Flow Analysis Results\
Pay attention to the Sink Mark in marked region.
Gate

18. Clamp Force Centroid locates
Flow Analysis Results\
Clamp Force
Clamp Force Centroid locates
in the center of mold.
Clamp Force(Max.=61.3Ton)
Variation curve of pressure&clamp force in cycle time shown by above figure.

19. Cool Analysis Results\
Coolant Temp
Coolant temp difference is very small,so the number of circuits is enough.
Temp difference(Max.=0.23 deg.C)

20. Temp (part) Cool Analysis Results\
The distribution of temp is not very uniform.
Pay more attention for the cooling in marked region.

21. Temp (part) Cool Analysis Results\
Pay more attention for the cooling in marked region.

22. Cool Analysis Results\
Frozen Time(part)
Click for animation.

23. Frozen Time(part) The frozen time is non-uniform.
Cool Analysis Results\
Frozen Time(part)
The frozen time is non-uniform.
The frozen time of most area is about 23 S, 6.1S in gate area.
Pay more attention for the cooling in marked region.

24. Cool Analysis Results\
Frozen Time(gate)
The frozen time of gate is about 6.45S,less than the frozen time of most area in the part,which will do harm to packing.
Design larger gate.

25. X Deflection Warp Analysis Results
The X direction belongs to natural shrinkage basically.

26. Y Deflection Warp Analysis Results
Deflection in Y direction is shown in the left plot, belongs to natural shrinkage basically.

27. Z Deflection Warp Analysis Results
Deflection in Z direction is uniform.
0.58
0.41
0.42
Gate

28. Conclusions&Suggestions
From the above analysis:
Some weld lines maybe affect the strength of molding part, and air traps are vented easily.
The packing effect is the main cause of sink mark,deflection. Deflection is very uniform,improve packing will get small deflection.
The distribution of temp is not very uniform.
Suggestions:
To use baffle,bubbler and inserts to improve cooling effect.
To design larger gate.