1. OPTIMIZATION OF PART AND MOLD DESIGN
FOR CYCLE TIME REDUCTION
Dr. Ir. O. Verhoyen
OPTIM TEST CENTER,
Rue Bonne Fortune, 102
4430 Ans
BELGIUM
Content
› Who is Optim Test Center ?
› The container project
• Concept 1 : Initial design
• Concept 2 : Wall thickness reduction
• Concept 3 : Conformal cooling channel
• Concept 4 : Caloducs
› Summary & Conclusions
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2. Who is Optim Test Center ?
40 years of helping our customers grow by developing
and supplying top level plastic parts
www.simonisgroup.be
Belgium: China:
rue Bonne Fortune, 102 - 4430 Ans No. 228 Jinxing 2 Road - YuYao Mould City - 315400 Zhejiang
Tel: +32 (4) 239-8833 Tel: +86 (0)159 8864–1778
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3. Parts Design and Development
Material Selection
Design Support
Rapid Prototyping
Mould Design
Numerical Simulation
Mould Manufacturing
Mould Validation
Excellence in Injection Moulding
› Custom Moulding (6-550To)
• 2K Injection Moulding
• Clean room production
› Production Automation
› Part Finishing
• Painting
• metallisation
› Sub-Assembly
• US welding
• Clean room assembly
› Quality
• ISO 9001
• ISO 13485
• ISO 14001
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4. Simonis Group Produces Top Quality Parts
AERONAUTICS AUTOMOTIVE RAIL MEDICAL
R&D,
Material Mould Design, Mould Quality Post-
Project Concept Selection
Simulation, Testing Injection Production
Management Studies, &
& &
Prototyping Moulding Operations
Parts Design Manufacturing Validation
Defense INDUSTRIAL ELECTRO-TECHNICS
MACHINES
The container project
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5. Container Project history
› Concept 1 : First (Prototype) Design based on the old packaging
• 2mm thickness
• Conventional cooling mold concept
› Concept 2 : Second (Production) Design with a wall thickness
reduction
• 1,3mm thickness
• Conventional cooling mold concept
› Concept 3 : Second design
• 1,3mm thickness
• Mold with Conformal cooling channel
› Concept 4 : Third design
• Minor changes due to Cartouche diameter reduction
• 1,1-1,3mm thickness
• Mold with Caloducs
Concept 1 : Prototype design
› Customer’s request C0
• To adapt the packaging to his new product
• To reduce the packaging volume
› Prototype design
• Size: 26 x 36 x 53mm
• Thickness: 2mm C1
• Material : PP
› Prototype mold
• 1 cavity
• Hot nozzle
• Steel
• Conventional cooling (baffle)
› => Cycle time:45s
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6. Concept 2 : Production Design
› Concept 2 : Production Design
• Size: 26 x 36 x 53mm
• Wall thickness reduction C1 C2
- 1,3mm thickness
• Add of one functional rib
• Material : PP
• Series: 50000 parts/year
› Production mold
• 1 cavity
• Hot nozzle
• Steel
• Conventional cooling (baffle)
Mold thermal analysis
› With the same injection parameters
Material PP
Cooling time 30 (s)
Cooling channel temperature 10°C
Melt temperature 250°C
Eject temperature 120°C
Report 6055
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7. Mold thermal analysis
C1 C2
The temperature for the core is decreased by 25°C (107°C  81°C)
Report 6055
Thermal analysis
C1
V1 C2
V2
The cooling time is the time needed to reduce the temperature of the part from
injection temperature (250°C) to ejection temperature (120°C).
With the C2 design the cooling time is reduced by 15 (s)
Report 6055
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8. C1 – C2 comparison
› With the C2 configuration
• A reduction of cooling time of around 15(s) is observed
• A reduction of the core temperature of around 25°C is observed
C1 C2
› Cycle time reduction from 45s to 30s
• Still too long but the mould has been build by classical mould
manufacturing with a conventional cooling baffle
• The narrow space in the core Moulding area
do not allow the possibility to
place cooling channel into the
moulding area
› Concept 3
• Use of conformal cooling to improve cooling efficiency
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9. Concept 3: Use of conformal cooling to improve cooling
efficiency
› Medical sector
› Material: PP
C2
› Size: 26 x 36 x 53mm
› Thickness: 1.3 mm
› Part very tiny:
• Core insert with a very narrow space
• =>internal cooling very difficult
• => productivity issue (cycle time 30s)
› Quality issues
• Difficulties for ejection: warpage and
tearing off plastic in the bottom, due
to the higher T°
› Series 150000 parts/year
› => Target reduction of the cycle time
to less than 20s.
Hipermoulding mould concept (C3)
› Tool material: steel 1.2344 (50
HRC)
› Exploiting the possibility to reuse
the existing supply and return
channels
› The only modification in the
production mold
• the length of the tube
• the extra sealing ring in top of the
tube to separate the inlet and
outlet
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10. Insert drawing
› New design of the core insert cooling channel to
increase the heat exchange in the moulding area
• The channel was generated by the Hipermoulding
software in PowerShape.
• Conformal cooling channels have a diameter of 1.5
mm.
Conformal cooling layout
Design Validation by Moldex 3D
Conventional cooling design Hipermoulding cooling design
C2 C3
Moulding area
Moulding area
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11. Mold Temperature after cooling time
C2 C3
Conventional cooling design Hipermoulding cooling design
Around 100°C
Less than 20°c
Required cooling time
Conventional cooling design Hipermoulding cooling design
C2 C3
To obtain a temperature of 110°c all over the To obtain a temperature of 110°c all over the part
part, Moldex estimate a cooling time of 15 s with a coolant flow rate of 35 cm³/s, Moldex
estimate a cooling time of 7,5 s
(to reduce the pressure drop into the coolant, a
lower flow rate is necessary)
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12. Moldex3D results summary
› With the C3 configuration
• A reduction of cooling time of around 8(s) is simulated
• The core temperature exceed the set point of the coolant by 10 °C
(against 90°C for the C2 concept)
• Cycle time is reduced from 30 sec to 20sec
- The cycle is improved by more than 30%
•  Need to find a technical solution to manufacture this third concept.
Core Insert manufacturing
› Laser melting mold manufacturing technology (ConceptLaser)
• Reduction of the LBMM building time by splitting the insert in two blocks
• CNC Machining of the base
• Building top part by Laser melting with 0,3mm overdimension
• Finishing
- CNC machining
- Heat treatment
- EDM is required to finish the fine slots
- Polishing with Norton Paper to P600 grit
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13. Cycle time comparison for Concept 3
(core insert with conformal cooling channel)
1,3mm thickness (conformal
cooling)
Simulation Real
Cooling time 7,5 7
packing time 8,5 6
Subtotal 15,5 13
stroke time 0,5 0,9
open time 4 4,5
Total 20 18,4
Conclusions
› With the optimised cooling design :
• Improvement of part quality
- Important reduction of the core temperature (20°c against 100°c)
• Improvement of productivity
- Important reduction of the cooling time
(4,5-7,5s against 15s depending of the coolant flow rate) )
› The conformal cooling insert was in production during 1 year …
until obstruction of the tiny channels
› => Potential problems to solve
• Water treatment
• Stainless steel
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14. Concept 4: Need of a new part design
› Medical sector C4
› Material: PP
› Size: 26 x 36 x 53mm
› Thickness: 1,1-1,3 mm
› Part very tiny:
• Core insert with a very narrow space
• =>internal cooling very difficult
› Quality issues
• Difficulties for ejection: warpage and
tearing off plastic in the bottom, due
to the higher T°
› Series 300000 parts/year
› => Target reduction of the cycle time
to less than 20s.
C4 mould concept
› 2 cavities mold
• Hot runner
› Tool material:
• steel 1.2344 (50 HRC)
› Conventional Cooling channels
• Use of caloducs
› => Cycle time:22,5s
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15. Summary & Conclusions
Summary
› C1 conventional cooling 45s
2mm thickness
-33%
› C2 conventional cooling 30s
1,3mm thickness
-35%
-25%
› C3 conformal cooling 19s
1,3mm thickness
+18%
› C4 caloduc cooling 22,5s
1,3mm thickness
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16. Conclusions for cycle time optimisation
› Think part design
e.
2
10
6 
8 T T 
• Thickness tcool   ln 2  melt mold 
a. 2   T T 
• Thermal conductivity of the material  eject mold 
› Think mold design
• Alternative conventional cooling methods
- Copper / BeCu inserts
- Caloducs
- …
• Conformal cooling
- Where conventional is not possible
- Where surface temperature homogeneity is a must
 aesthetical parts
THANKS FOR YOUR ATTENTION
Contact : Dr Ir O. Verhoyen
Email : olivier.verhoyen@optim.be
As partner of
www.optim.be
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