转子系统在注塑模具设计中的椭圆截面形状

转子系统在注塑模具设计中的椭圆截面形状(中文5300字,英文3700字)
摘要
本文介绍了注射成型工艺模具设计中流道系统的一种新的横截面形状。新几何结构的目标是减少废料，缩短周期时间，并减轻模具工具的流道系统弹出。针对两个厚度为1mm的圆形平板，提出了具有不同比例的椭圆横截面形状。 SolidWorks Plastic采用有限元法（FEM）来模拟注塑零件。 SolidWorks Plastic分析了注塑成型过程中塑料零件的短缺缺陷，以验证新建议的几何结构。对新的几何结构进行了聚丙烯圆形平板注射成型工艺的实验研究。所选择的输入机器参数是填充时间，熔体温度，模具温度，压力保持时间和纯冷却时间。研究结果显示，与新的几何形状相比，没有短路缺陷，与圆形截面相比，废钢和冷却时间分别显着减少25％和2.5％。流道系统与模具壁的接触表面的减少也改善了流道系统从模腔排出的容易性。这项研究的贡献是设计冷流道系统的新几何结构，以减少废料，循环时间，并提供注射成型中流道系统的简单排出。

关键词 注塑工艺；模具设计；浇道几何形状；短缺缺陷

Elliptical cross sectional shape of runner system in injection mold design
Mehdi  Moayyedian1    •     Kazem  Abhary1    •
Romeo Marian1
Received: 3 June 2015 / Accepted: 21 July 2016 / Published online: 27 July  2016
© Central Institute of Plastics Engineering & Technology   2016
Abstract This paper presents a new cross sectional shape  of the runner system  in the mold design of the injection molding process. The aim of the new geometry is to reduce scrap, cycle time and ease the ejection of runner system from mold tools. An elliptical cross sectional shape of runner with different ratios was proposed for two circular flat plates with thickness 1 mm. Finite element method (FEM) is employed in SolidWorks Plastic for simulation of the injected part. Short shot defect in the plastic part during the injection molding process is analyzed by SolidWorks Plastic to validate the new proposed geometry. An experimental study of the injection molding process of polypropylene circular flat plates is conducted for the new geometry. The input machine parameters selected are filling time, melt temperature, mold temperature, pressure holding time, and pure cooling time. The research outcomes show no short shot defect associated with the new geometry and also significant 25 and 2.5 % reduction in scrap and cooling time respectively compared to round cross sections. Reduction in contact surface of the runner system with mold walls improved the ease of ejection of runner system out of the cavity as well. The contribution of this study is to design a new geometry of a cold runner system to reduce scrap, cycle time and also provide easy ejection of runner system in the injection molding.
Keywords Injection molding process • Mold design • Runner geometry • Short shot defects