Numerical Study on Local Heating for Thin-Walled Product by External Air Heating

Abstract

Gas-assisted mold temperature control (GMTC) is a new technique in the field of mold temperature control. It enables rapid heating and cooling of the cavity surface during the injection molding process. In general, the goals of mold temperature control are to increase the mold surface to the target temperature before filling of the melt and to cool the melt to the ejection temperature. In this paper, dynamic mold temperature control is used for a thin-walled molding part as the temperature distribution and the heating rate are observed. The heating step of DMTC is achieved via hot-air flow directly to the thin-walled area. The results show that the heating rate reached 7.0 °C/s and that the temperature of the mold surface increased from 25 °C to greater than 165 °C within 20 s. A comparison showed that the difference between the simulation and experiment temperatures was less than 5.0 °C. Thus, this method can be used to accurately predict the outcome of a heating step before the actual process is carried out.