框形零件浇口的优化设计

翘曲变形是框形零件在注塑成型生产过程中产生的主要缺陷.翘曲变形不仅影响产品的外观、尺寸,严重时还会影响后续的装配.塑件产生翘曲变形的因素有很多,除了工艺参数的设置、模具的加工制造,还有一个很重要的因素就是模具结构的设计.传统的模具设计主要依靠设计人员的经验,但随着人们对产品的综合要求越来越高以及模具行业本身的竞争日益激烈,仅依靠工程技术人员的经验,很难在短时间内精确地设计出既可降低成本,又可提高产品质量和合格率的最佳方案.因此CAE技术越来越受模具设计人员的青睐.以框形零件为例,采用具有注塑成型仿真工能的软件模拟分析了3种不同浇口方案下塑件的注射成型过程:方案一熔接痕出现在矩形边框,变形呈下凹趋势,最大变形量为0.533 2mm;方案二熔接痕出现在主体区域,变形呈外凸趋势,最大变形量为0.497 1mm;方案三熔接痕出现在主体区域,各部位变形基本一致,最大变形量为0.437 3mm.通过分析比较,方案三为最优化设计.该模拟结果可为实践生产提供参考,缩短产品的试模周期.

Moldflow-based optimization design of injection mould gate for box-shaped part

Warpage is the main defect of the box-shaped parts in the injection molding production process. There are many factors, including the process parameters, manufacturing and design, leading to defects. Traditional mold design is based on the experience of the designers, but with the increasing high demand of the products and the increasing competition, it is difficult to design a good program with low costs and high quality only relying on the engineering and technical personnel. So, CAE becomes more popular. Three injection molding processes for a box-shaped part were simulated by Moldflow software in which the simulation results of melt flowing and filling status, and warping deformation were compared and analyzed： In the plan one, weld lines appear in the rectangular frame, deformation trend is concave and maximum deformation is 0. 533 2 ram; in the plan two, weld lines appear in the subject area, deformation trend is convex and the maximum deformation is 0. 497 1 ram; in the plan three, weld lines appear in the subject area, each part deformation is basically the same and maximum deformation is 0. 437 3 ram. At last, the optimum gate is obtained for molding and the tryout period reduces a lot.