Mais conteúdo relacionado Semelhante a The Isoplaten -"Thermal Performance of Electrically Heated Platens" - May 2011 (6) The Isoplaten -"Thermal Performance of Electrically Heated Platens" - May 20112. Introduction to Isoplatens®
Heated platens are fundamental components in
the molding process of a variety of composites.
Platens provide heat necessary to complete the
molding /curing reaction.
Conventionally heated platens consist of a single
level of heaters housed in a plate.
Acrolab’s Isoplaten® is a bi-level matrix of
heaters and Isobar® heat pipes housed in a metal
plate.
Acrolab Ltd.© May 2011
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3. Standard Platen With Heaters
Standard
electrically
heated platen
with five
cartridge
heaters and one
thermocouple
Acrolab Ltd.© May 2011
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4. Standard Platen With Heaters
Electrically
heated
Isoplaten® with
5 cartridge
heaters (yellow)
and 17 Isobars®
(white & red)
Acrolab Ltd.© May 2011
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5. Standard Platens
Standard platens do not
provide uniform temperature
distribution on the plate
surface.
Temperatures can vary by
up to 25 C along the surface
of the platen.
Non-uniformity can result
in insufficient curing,
increased cycle times,
Thermogram of a standard electrically
heated platen
decreased thermal recovery,
and poor part quality.
Acrolab Ltd.© May 2011
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6. Isoplatens® “Provide for exceptional temperature uniformity”
Temperature distribution varies
only 2 C across 95% of the
platen.
Temperature uniformity results in:
1. Decrease in under and over
cured parts
2. Rapid temperature recovery
3. Decreased cycle times
4. Reduced energy consumption
5. Improved overall part quality
Thermogram of an electrically
heated Isoplaten®
Acrolab Ltd.© May 2011
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7. Research Experiment
Objective:
A comparative analysis of an
electrically heated Isoplaten® vs. a
conventional or standard electrically
heated platen of the same physical
dimensions, the same thermal energy
in-put and with the same load
conditions.
Acrolab Ltd.© May 2011
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8. Experiment Stages
Steady state, loading, boiling/thermal
footprint growth, beginning of recovery,
recovery, complete recovery.
Isoplaten® with 20mL of water in 4” load
container; central loading location (5)
Raw data from “Thermacam Researcher” as
seen during experiment.
Acrolab Ltd.© May 2011
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9. Overview: Research Experiment
1. To characterize the difference in thermal response between
conventional standard platens and Isoplatens® when subjected to
various thermal loads, at different load positions.
2. A comparative examination of the surface thermal uniformity of
either platen when they are subjected to random cartridge heater
failures.
Standard Platen Isoplaten ®
Acrolab Ltd.© May 2011
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10. Experiment - Set up
Equipment
18” x 18” Isoplaten
IR Camera: FLIR
SC3000
Sampling rate: 1 Hz
Image size: 320 x
180
DAC: Real-time
monitoring
Recording of IR
image sequence
Acrolab Ltd.© May 2011
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11. Configuration common to both platens
Loading Container Loading Positions
Load
Chamber
Acrolab Ltd.© May 2011
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12. Experiment Phases (3)
Phase 1: Comparative dynamic thermal load analysis
a) Steady state
b) Loading
c) Boiling/thermal footprint growth,
d) Beginning of recovery
e) Recovery
f) Complete recovery
Acrolab Ltd.© May 2011
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13. Phase 2 – Position #5
20 mL of water in 4” load chamber; central loading position #5
(both platens)
Load
Chamber
Position# 5
Acrolab Ltd.© May 2011
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14. Position #5 - Temperature difference Isotherms
Loading at location 5 (center of platen)
T(t)-T0 are plotted during the recovery period
Acrolab Ltd.© May 2011
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15. Position #5 - Animated sequences
Absolute Temperature
Platen Isoplaten
Acrolab Ltd.© May 2011
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16. Position #5 - Animated sequences
Temperature Difference
Platen Isoplaten
Acrolab Ltd.© May 2011
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17. Thermographic video sequence
1. Steady state
2. Loading
3. Boiling/thermal footprint growth,
4. Beginning of recovery
5. Recovery
6. Complete recovery
Acrolab Ltd.© May 2011
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19. Phase 2 – Position #7
20 mL of water in 4” load chamber; central loading position #7
(Both platens)
Load
Chamber
Position# 7
Acrolab Ltd.© May 2011
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20. Position #7 - Animated sequences
Absolute Temperature
Platen Isoplaten
The true measured temperature
Acrolab Ltd.© May 2011
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21. Position #7 - Animated sequences
Temperature Difference
Platen Isoplaten
The temperature difference between the two platens
Acrolab Ltd.© May 2011
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22. Conventional platen vs. Isoplaten®
Conventional Platen Acrolab Isoplaten®
Isoplaten:
Uniform heat distribution = Quality improvement
Reduction of hot spots in molds = Quality Improvement
Uniform cure rate = Quality Improvement
Improvement of cycle time = Productivity improvement
Reduction of thermal energy required from heaters = Energy Savings
Acrolab Ltd.© May 2011
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23. Summary
Steady-state performance of the Isoplaten is
improved over that of the platen, even with
heater failure.
Recovery time is reduced in all loading modes:
C (θ = 63%) 7 – 26 %
T (within 1 C of SS) 14 – 30 % (or more)
The recovery time is mostly affected by load
position.
Acrolab Ltd.© May 2011
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24. Results
The Isoplaten® provides for curing times that
are shorter than the standard platen.
The time over the standard platen. faster
curing
Isoplaten® provides for a 44-54%
The Isoplaten® also has a faster recovery
time.
The Isoplaten® will decrease cycle times and
energy consumption.
Acrolab Ltd.© May 2011
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25. Acrolab R & D Labs & Manufacturing Centre
Let our team at Acrolab optimize your thermal footprint … call today.
1 800 265 9542 Toll free in North America
1 800 465 9674 Fax
519 944 5900 Direct
www.acrolab.com
©Acrolab 2011 Advanced Research & Development 25