Customer : TYCO

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Customer TYCO Part No. C5C Material
PBT-VALOX 357-SABIC(GE) Analyser Johnson Xu
Report Date 25th Mar , 2008
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• Background Information
• Main Thickness 1.2 mm
• Length 120 mm
• Width 18.85 mm
• Height 36.5 mm
• Volume(1 Cavity) 103.356 c.c.
• Original Plastic Material
• PBT-VALOX 357-SABIC(GE)
• Original Process
• Fill Time 0.12 Sec
• Melt Temp 260 ?
• Mold Temp 80?

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Original DesignMaterial Information PBT-VALOX
357-SABIC(GE)

• Viscosity
• Viscosity is a measure of the resistive force of
  a fluid against the flow. The higher the
  viscosity the higher the resistive force and
  flow becomes more difficult. For typical
  thermoplastic, viscosity is a function of the
  plastics composition, temperature, pressure ,
  shear rate, etc.
• pvT Relationship
• Because the specific volume or density of
  thermoplastic is defined as a function of phase
  state, temperature and pressureetc., we can
  commonly derive and quantify it with a state
  equation (or a PVT equation). Once the parameters
  in the PVT equation were acquired from
  experiments, they can be used to calculate the
  value of the specific volume or density at any
  given temperature and pressure.

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Original DesignMaterial Information PBT-VALOX
357-SABIC(GE)

• Heat Capacity
• The thermal energy required to increase the
  temperature one degree per unit mass of polymer.
  Polymer with high specific heat are more
  insensitive to temperature variations, and vice
  versa.
• Thermal Conduction
• Thermal conductivity is a measure of the thermal
  conduction characteristics of a substance. A
  higher thermal conductivity is equivalent to an
  excellent effect of thermal conduction, i.e.,
  polymer tends to have a uniform temperature
  without hot spots caused by accumulation of local
  thermal energy. Thermal conductivity and specific
  heat are closely related to polymer heat transfer
  and cooling characteristics , they can also
  affect the cooling time.

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Original DesignMaterial Information PBT-VALOX
357-SABIC(GE)

• Content

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Original Design Runner Layout
Hot Runner
RunnerØ5.5mm
Gate Ø1
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Original Layout Process Conditions
Flow Rate
Injection Pressure
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Original Design Part Thickness
???? 4 mm ???? 1.2 mm ???? 0.6 mm
1.5mm
1.5mm
0.6mm
1mm
2mm
1.2mm
2.5mm
1.7mm
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Original DesignMelt Front 10
The advancement of melt front at different time
is displayed by different color. The time scale
is shown in color bar. From the melt front
advancement one can examine the filling/packing
pattern of the melt. Incomplete filling/short
shot, over-pack flash, weld line, and air trap
problems can be detected and avoided by modifying
design or processing variables.
10
Welding Line
10
Original DesignMelt Front 20
The advancement of melt front at different time
is displayed by different color. The time scale
is shown in color bar. From the melt front
advancement one can examine the filling/packing
pattern of the melt. Incomplete filling/short
shot, over-pack flash, weld line, and air trap
problems can be detected and avoided by modifying
design or processing variables.
20
????????(1mm)???,????????????????
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Original DesignMelt Front 35
The advancement of melt front at different time
is displayed by different color. The time scale
is shown in color bar. From the melt front
advancement one can examine the filling/packing
pattern of the melt. Incomplete filling/short
shot, over-pack flash, weld line, and air trap
problems can be detected and avoided by modifying
design or processing variables.
35
12
Original DesignMelt Front 55
The advancement of melt front at different time
is displayed by different color. The time scale
is shown in color bar. From the melt front
advancement one can examine the filling/packing
pattern of the melt. Incomplete filling/short
shot, over-pack flash, weld line, and air trap
problems can be detected and avoided by modifying
design or processing variables.
55
13
Original DesignMelt Front 75
The advancement of melt front at different time
is displayed by different color. The time scale
is shown in color bar. From the melt front
advancement one can examine the filling/packing
pattern of the melt. Incomplete filling/short
shot, over-pack flash, weld line, and air trap
problems can be detected and avoided by modifying
design or processing variables.
75
Welding Line
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Original DesignMelt Front 98
The advancement of melt front at different time
is displayed by different color. The time scale
is shown in color bar. From the melt front
advancement one can examine the filling/packing
pattern of the melt. Incomplete filling/short
shot, over-pack flash, weld line, and air trap
problems can be detected and avoided by modifying
design or processing variables.
98
Welding Line
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Original DesignMelt Front 100
The advancement of melt front at different time
is displayed by different color. The time scale
is shown in color bar. From the melt front
advancement one can examine the filling/packing
pattern of the melt. Incomplete filling/short
shot, over-pack flash, weld line, and air trap
problems can be detected and avoided by modifying
design or processing variables.
100
Vent Position
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Original Design Melt Front Animation
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Original Design Melt Front Animation
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Original Design Flow / Pressure
From the pressure distribution one can check the
pressure transmission situation and detect if
there is any over-packing problem.
??????????87.8 MPa
??????30.5MPa
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Original Design Flow / Center Temperature
Center temperature is the melt temperature of the
middle layer(partline) in the thickness direction
at EOF/EOP. Center temperature is an indicator of
thermal energy supply of the fresh hot melt. In
general , the center temperature is an indicator
of incomplete filling(short shot).If the center
temperature is too low, flow hesitation happens
and there will be a short shot problem.
??????????257.58267.28ºC
??????????33.28ºC
????????,??????,????????????,??????
????????260ºC??,??????
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Original Design Flow /Shear Stress
Shear stress at EOF/EOP is shown in different
color according to different stress level.Shear
stress is one of source of the molded-in residual
stress in molded parts. If the shear stress is
not distributed evenly, it will cause some
dimensional problems.Too high the shear stress
level will result in stress-induced problems in
the molded part. The shear stress should be
controlled to be lower than 1 MPa.
????????????00.971MPa
???????????????1 MPa??,????????????????
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Original Design Flow /Shear Rate
The distribution of shear rate of part cavity is
shown in different colors at the moment of
EOF/EOP. Shear rate is the rate of shear
deformation of the material while the polymer is
being proceeded. A higher shear rate of polymer
is equivalent to a higher rate of deformation,
i.e. the molecular chains were drastically
deformed and got no chance to relax or recoil.
Therefore, shear rate distribution is related to
the variation of velocity gradient and molecular
orientation.Shear rate reveals the velocity
gradient of the flow field and is related to
molecular/fiber orientation, viscous
heating...and so on. High shear rate tends to
deform molecular chain and will lead to
degradation problem. If the shear rate is too
high,molecular chain will be broken and the
strength of products will be decreased. Viscous
heating due to high shear rateshould be
noticed.The shear rate should be controlled to be
smaller than 10,000 sec-1 in general.
??????????10000 1/Sec????
?????10000 1/Sec??????????????????????
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Original Design Packing / Volumetric Shrinkage
Volumetric shrinkage shows the percentage of part
volume change due to pvT change as the part is
cooled from high temperature, high pressure
conditions at EOF/EOP to room temperature,
ambient temperature conditions.Positive value
represents volume shrinkage while negative value
represents volume expansion due to
over-pack.Non-uniform volumetric shrinkage will
lead to warpage and distortion of demolded parts.
?????????? 015.277
????????,?????????????
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Original Design Cooling / Volumetric Shrinkage
Volumetric shrinkage shows the percentage of part
volume change due to pvT change as the part is
cooled from high temperature, high pressure
conditions at EOF/EOP to room temperature,
ambient temperature conditions.Positive value
represents volume shrinkage while negative value
represents volume expansion due to
over-pack.Non-uniform volumetric shrinkage will
lead to warpage and distortion of demolded parts.
?????????? 015.277
????????,?????????????
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Original Design Warpage / X-Displacement
Shows the X-component of the total displacement (
All effects are considered)after the part is
ejected and cooled down to room temperature.
X???????? 1.255 1.210mm
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Original Design Warpage / Y-Displacement
Shows the X-component of the total displacement (
All effects are considered)after the part is
ejected and cooled down to room temperature.
Y???????? 0.22690.2154mm
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Original Design Warpage / Z-Displacement
Shows the Z-component of the total displacement (
All effects are considered)after the part is
ejected and cooled down to room temperature.
Z???????? 0.26930.5873mm
-
Z???

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Original Design Warpage / Total-Displacement
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Original Design Warpage / Warpage_Total
Differential Shrinkage Displacement(PVT Effect)
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Conclusion

• 1. ?PBT??????? 245275?,?????232
  ?,?????,????????????,???????0.2s??,???????????????
  ???
• 2. ???????????????,???????????,???3s
• ??????????,?????0.015-1.275mm,Z????????0.26930.5
  873mm
• ???????????,?????????

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Thank you!