Abstract
In this paper, a correlation analysis between the melt temperature variation inside the nozzle measured using an integrated thermocouple ceramic sensor and the observations of the plastication state using a visual-heating cylinder was carried out, and improvements in the melt temperature variation using a barrier flight screw were studied. The results can be summarized as below:
(1) The temperature deviation profile inside the nozzle showed a maximum around 2.4mm from the nozzle center during the continuous plastication process and around 1.8mm from the center during the reciprocating plastication process.
(2) From the results of the correlation analysis between the melt temperature at the nozzle and observations using the visual-heating cylinder, we confirmed that the melt temperature variation is directly influenced by the plastication state inside the heating cylinder, especially the solid-bed break-up phenomenon.
(3) We confirmed the decrease of the solid-bed after the sub-flight of the barrier flight screw and the considerable effects that this decrease had on the uniformity of the melt temperature.
From the results above, the validity of the melt temperature variation inside the nozzle as a monitor for the synthetic measurement of the plastication state or as a screw evaluation system was proved by the combination of this sensor and the visual-heating cylinder.
