Study On Injection Molding Parameter Based On Cavity Pressure Monitoring Technology

Plastic injection process is widely applied in various industrial fields, which is an importantproduction method to produce plastic products. At present, the precision and update cycle ofplastic products in various fields is required to higher and higher. However, the adjustment ofinjection parameters always depends on engineers’ experience, which lacks reliable scientificbasis and is in low efficiency. The change of melt plastic in the cavity of the injection process canbe directly viewed by the means of cavity pressure sensor. In this paper, cavity pressure andtemperature were taken as research object to research the relationship between the cavity pressurecurve and product warpage. The effects of injection parameters and mold structure on the cavitypressure and temperature was also researched.BP neutral network was used to establish the prediction model for the plastic products warpagein this paper. According to the characteristics of the cavity pressure curve,3characteristic valueswere extracted from the cavity pressure curve, as are Pmax(maximum of cavity pressure),△t1(injection time length) and△t2(shaping time length). And the3cavity pressure curvecharacteristic values were chosen as the network input parameters, while the warpage as theoutput parameters. The prediction network was established, trained and tested on the Matlabsoftware platform. The warpage prediction model was established on the basis of cavity pressurecurve. And the effectiveness and robustness of the prediction model was verified.Orthogonal experiment was adopted to conduct in the mold with ingate sleeves of2°and4°.And the influence laws of injection pressure, injection time, parking pressure, melt temperatureand mold temperature on the maximum of cavity pressure and temperature were researched. Theresults indicate that packing pressure is the significant factor for the maximum of cavity pressurein the mold with ingate sleeve of2°. Above-mentioned injection parameters don’t have significanteffects on the maximum of cavity pressure in the mold with ingate sleeve of4°. As to themaximum of cavity temperature, mold temperature is a significant factor in different moldstructure.