Research On Hot Runner System Of PET Bottle Preform Mould With72Cavities In One Mould

The great development of economy has brought a large improvement to plasticsindustry．As one of the main forming methods，the injection also grew fast in the past fewdecades．However，the quantity of demand for plastic products has been so large that thetraditional forming methods cannot meet the requirements．Hot runner technology is one ofthe advanced injection technologies which has been used by more and more mold companiesbecause of its significant advantages such as higher quality and efficiency，shorter productioncycle，less costs，and etc．This article researchs on hot runner system of PET bottle preform mould with72cavities in one mould，firstly，combined with the performance of PET material and the processof injection molding as well as based on the rheology principles，the paper uses the naturalbalance method to design gating system of PET preform which has72-cavities in one mold，analyzes plastic melt filling in the flow channel and optimizes the section size of flow channelat various levels with the help of Moldflow software；Secondly，based on the principles ofheat transfer，study manifolds temperature field with the help of ANSYS Workbench (AWB)software，which provides evidence for manifold heaters reasonable arrangement；Thirdly，hot runner system works at high temperature，so the major components of hot runner systemwhich install at room temperature change their relative positions due to thermal expansion，therefore studying the thermal expansion of manifold contribute to the analysis of manifoldheat compensation as well as providing guidance for the deformation of each template；Fourthly，doing some experiments for the PET bottle preform mould with72cavities in onemould，such as the measurement of the height of the nozzle needle valve，the heating test ofthe hot runner manifold，the measurement of the cavity plate flatness；The study in the paperwill provide guidances for design and analysis of large-scale and multi-cavities precisioninjection mold．...