瓶坯尺寸对拉伸吹塑成型PET瓶壁厚分布的影响

摘要

通过对多个瓶坯的拉吹成型过程进行模拟分析，预测出不同尺寸的瓶坯所成型的PET瓶壁厚分布，并分析比较瓶坯尺寸对制品壁厚分布的影响。结果表明，瓶坯尺寸对于拉吹成型PET瓶的壁厚均匀性有较大影响，其中瓶坯局部厚度及瓶坯高度是主要影响因素。瓶坯整体壁厚对PET瓶轴向壁厚分布影响较小。PET瓶（不考虑体积时）最优瓶坯高度受瓶坯壁厚影响不大，采用有限元建模(FEM)仿真试验进行模拟分析可得到瓶坯最优高度取值范围。通过模拟计算和对瓶坯进行优化设计，可显著提高吹塑成型PET瓶的壁厚均匀性，且有助于PET瓶轻量化设计。%The size distribution of the wall thickness of PET bottle molded by its preform with different sizes was predicted through the simulation analysis of stretch-blow molding process of multiple performing. The effect of preform sizes on the thickness distribution was analyzed as well. The results show that the size of stretch-blow molding preform of PET bottles have a greater impact on the wall thickness uniformity of products, the preform thickness and partial height are the main factor. The impact of the overall thickness of preform on the uniformity of axial wall thickness distribution of PET bottles is relatively small. The optimal height of PET bottle preform, regardless of volume is little affected by the perform wall thickness. The optimal height value range of bottle preform is available by the FEM simulation experiment for simulation analysis. The simulation and optimization design for preform can significantly improve the thickness uniformity of blow molding PET bottle, and contributes to the lightweight design of PET bottles as well.