基于Moldflow的轿车后视镜镜框注塑工艺优化

Optimization of Injection Molding Process for Car Rearview Mirror Frame Based on Moldflow

以轿车后视镜镜框为例,根据行标QCn29017–1991,确定了后视镜镜框塑件8个抽检尺寸的尺寸公差。在Moldflow 2021 DOE功能的帮助下,采用田口方法筛选因子,建立了针对塑件尺寸公差影响产品合格率的两响应(优化目标)7因子实验方案。通过模流分析,分别确定了对2个响应影响最大的3个因子。选用响应面法中的Box-Behnken Design(BBD)实验设计方法,建立针对两个响应的两大组实验。根据实验结果利用Minitab建立分析模型并求解最优值。在考虑因子实际取值范围和工艺条件容易实现的情况下,分别求解两个响应取最小值时对应因子的取值。用Moldflow证明体积收缩率和翘曲变形量都大幅度降低。结果表明,利用Moldflow2021 DOE功能能快速筛选出对响应影响较大的因子,结合Moldflow的模流分析、响应面法和Minitab,无论是几个响应,也无论因子是否有交互作用,该法都能够快速有效地解决因子取值问题。该研究方法能够高效地解决复杂条件下工艺参数的取值问题,在不改变模具结构的情况下能够有效提高塑件产品合格率。

Taking the car rearview mirror frame as an example,according to the standard QCn29017–1991,the dimensional tolerances of 8 sampling dimensions of rearview mirror frame plastic parts were determined.With the help of Moldflow 2021 DOE function,Taguchi method was used to screen factors,and a 2-response(optimization objective),7-factor experimental scheme for the influence of plastic part dimensional tolerance on product qualification rate was established.Through mode flow analysis,the three factors that have the greatest impact on the two responses were determined respectively.Using the Box-Behnken Design(BBD)experimental design method of response surface method,two groups of experiments for two responses were established.According to the experimental results,Minitab was used to establish the analysis model(function)and solve the optimal value.Considering the actual value range of factors and the easy realization of process conditions,the value of the corresponding factor when the two responses take the minimum value was solved respectively.It is verified by Moldflow that the volume shrinkage and warpage deformation during ejection were greatly reduced.The results show that using Moldflow 2021 DOE function can quickly screen out the factors that have a great impact on the response.Combined with Moldflow’s model flow analysis,response surface method and Minitab,this method can quickly and effectively solve the problem of factor value regardless of several responses and whether the factors interact or not.This research method can efficiently solve the value problem of process parameters under complex conditions,and can effectively improve the qualified rate of plastic parts without changing the die structure.