Research And Opitimaze The Forming Process Of Injection-stretch-blow Molding Medicial PET Bottles

With its excellent physical properties and chemical properties, medical PETbottle has now become the most important medical replace glass containers. Itsforming process and the design of PET bottleneck are so complicated that both themanufacturing cost and bottle performance are affected. Therefore, many researchersstudied hard to find the forming process and design the PET bottleneck. The paper isfocused on the study of the Finite element simulation of streteh-blow molding of thePET bottle and achieve design optimization of process and PET perform dimensions.The research status of PET bottles and the numerical simulation of PET bottleblowing process and preform optimization were summarized. Then, the PET materialcharacteristics and forming process of PET bottles were analyzed. An optimizeddesign scheme for PET bottles was proposed which optimized the process conditionsand the size of PET bottle preform with the result data of numerical simulation for thestretch blow molding process of PET bottles by POLYFLOW software.Simulated stretch-blow molding phase of PET Serum separation bottle formingprocess by using the POLYFLOW software and, then, analyed the effect of theprocess conditions and preform size on the uniformity of wall thickness distribution.The optimization design was carried out based on the analysis. The result shows thatthe tensile speed, blowing delay time, preblow pressure and the size of stretch-blowmolding preform of PET bottles have a great impact on the wall thickness uniformityof products. The faster the tensile speed, the more uniform PET sidewall thicnessdistribution. However, too fast speed would easily lead to pull the preform broken.Bottle blowing delay time mainly have a great influence on the shoulder and bottompart of preform. It is beneficial to the uniform distribution of the wall thickness ofPET bottles in a certain range. The impact of preblowing pressure on the uniformthickness distribution around the bottom part of bottles is very obvious, too big or toosmall are not conducive to the uniform distribution of wall thickness. Secondaryblowing press--ure has little affect on the uniformity of axial wall thicknessdistribution. The impact of the overall thickness of preform on the uniformity of axial wall thickness distribution of PET bottles is relatively small while the impact of theheight and the partial preform thickness are great. Sectional preform thickness designcan effectively improve the uniformity of axial thickness distribution and reduce theweight of products. The optimal height value range and thickness distribution ofbottle preform ia available by the simulation experiment.The simulation andoptimization design for process conditions and preform cam significantly improve thethickness uniformity of blow molding PET bottles, and contributes to the lightweightdesign of PET bottles as well.