Low temperature nitrogen gas in gas-assisted injection moulding, as opposed to the conventional GAIM process, was used to produce hollow rod shape specimens, This new method aims to accelerate the cooling rate of GAIM samples by enhancing internal heat transfer from the Polymer at the gas channel internal surface. Although the concept seems relatively simple, its implementation required the development of new production equipment to be used with the standard GAIM. An overview of the set-up is described. Two methods for the injection of low temperature gas are considered. One consists on the simple injection of low temperature nitrogen gas, using conventional GAIM practice. The other employs the cyclic compression followed by adiabatic expansion of the low temperature gas, during the cooling stages. Gas temperature and pressure profiles, measured upstream of the gas injection nozzle, were compared for the different methods. Further, cavity melt temperature was recorded at different locations in the specimens and compared for the different methods. The effect of using low temperature nitrogen gas on the residual wall thickness distribution of the different specimens was assessed
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