Observation of Impact of Progressive Cooling System on Temperature Field Distributions on Surfaces of Injection Moulded Plastic Parts

Abstract:

Cooling the injection moulds with using of liquid CO₂ is rated among progressive and innovative tempering systems nowadays. In the ideal case this cooling method is chosen in combination with conventional drilled or milled tempering channels where the heat transfer medium flows. These wide-spread ways of cooling are not very often effective enough and they do not provide required accuracy of heat transfer control during production by injection moulding technology. Implementation of capillary tubes that bring the liquid CO₂ to critical zones enables local increasing of heat transfer. Regulation of liquid CO₂ amount that is injected into mould enables removal of required heat quantity in a very short time period. In this way the homogenous rate of part cooling can be achieved which is very difficult when producing the parts with complex geometry or with combination of various wall thickness. The final mechanical and physical properties of moulded parts accrue from properties of polymer material, part design and used technological parameters. This article deals with evaluation of technological parameters, concretely the cooling parameters of both the conventional cooling method and the system utilizing the cooling potential of liquid CO₂. The analysis is focused on observation of temperature field distribution on injected part surfaces.

• Periodical: Key Engineering Materials (Volume 669)
• Pages: 19-28
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.669.19
• Online since: October 2015
• Authors: Martin Seidl*, Jiří Bobek, Petr Lenfeld, Jiří Habr, Luboš Bĕhálek, Iva Nováková
• Keywords: CO₂, Injection Moulding, Spot Cooling

References

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