Verifying the Gas Heating Method for Injection Molding

In recently year, the plastic product is almost made by injection molding method. In this paper, a hot gas was used for mold heating with the gas temperature varied from 200°C to 400°C. The results showed that with three types of gas temperature, the heating rate is high in the first 20 s and the highest heating speed of 8.25°C/s could be achieved with 400°C gas. In all cases, the mold temperature has a limitation after 30 s of heating. In our experiment, the limitation of cavity temperature is 172.2°C. This cavity temperature is almost good for the melt flow in to the cavity, especially with the thin wall molding cases.