基于正交试验的医用微球囊拉伸吹塑优化设计

Optimization Design of Stretch Blow Molding Process of Medical Microballoon based on Orthogonal Test

为提高医用微球囊壁厚均匀性以及成型稳定性,以成型温度、成型压力、拉伸距离和保温时间四个拉伸吹塑工艺参数为优化对象,在完成田口正交试验与极值分析的基础上,进一步择优缩小各因素的水平范围,设计并实施了具有因素交互作用的正交试验。交互试验结果表明,成型温度和成型压力的交互作用及成型温度和拉伸距离的交互作用对球囊壁厚均匀性影响明显。依据两次正交试验获得的优化参数进行成型实验与测量统计,对比发现,交互正交试验优化结果下的球囊壁厚均匀性平均值略高于田口正交实验优化结果,达到96.03%,两者之间的差值为0.17%;但是两组参数下球囊壁厚均匀性的方差相差较大,前者相较于后者降低了10.58%,表明交互正交试验优化结果提高了球囊成型的稳定性。

An orthogonal experiment with factor interaction was designed and implemented with the level range of each factor was further narrowed based on the completion of Taguchi orthogonal test and extreme value analysis,taking the four stretch blow molding process parameters of molding temperature,molding pressure,stretching distance,and holding time as optimization objects to improve the uniformity of wall thickness and molding stability of medical microballoons.The interactive test results show that the interaction of molding temperature and molding pressure,as well as molding temperature and stretching distance,have obvious effects on the wall thickness uniformity of the balloon.The molding experiments and measurement statistics were performed based on the optimized parameters obtained from these two orthogonal tests.It can be found from the comparison that the average value of the balloon wall thickness uniformity under the optimization results of the interactive orthogonal experiment is 96.03%,which is slightly higher than that of the Taguchi orthogonal experiment,and the difference between these two experiments is 0.17%;however,the variance of the balloon wall thickness uniformity under the former test is reduced by 10.58%compared with the latter,which shows the great difference between these two tests and indicates that the optimization results of the interactive orthogonal experiment improve the ball stability of ball molding.