注塑成型中一模两腔流道平衡优化设计

Runner balance optimization design in double-cavity mold injection

具有配合关系的2个塑件一模两腔注塑成型时,容易产生填充、压力及温度不平衡等问题。文章通过理论计算和实验相结合的方法,分析了玩具电脑A、B面壳成型中存在的翘曲、飞边等缺陷,采用浇口平衡设计理论和有限元变截面法对该浇注系统进行优化设计。模拟结果表明,充填时间不平衡率控制在0.61%,充填压力不平衡率控制在3.87%,且翘曲值有所减小。优化后塑件缺陷分析结果表明,塑件飞边得到解决,翘曲有明显改善,从而说明流道平衡对改善塑件质量有较好的效果。

The two plastic parts with cooperative relationship are apt to the problems such as unbalanced filling, pressure and temperature in double-cavity mold injection progress. In this paper, the defects of toy computer A and 13 shells forming including warp and flash are discussed through the combination of theoretical calculation and experimental method. Furthermore, the design theory of runner balance and the finite element method of variable section are applied to optimizing the gating system. The simulation results show that the filling time imbalance rate and the filling pressure imbalance rate should be controlled at 0. 61% and 3.87% respectively, and the warp value decreases to a certain extent. Finally, the parts defects are analyzed through optimized experiment. The results show that plastic flash is solved and the warp is improved significantly, which indicates that runner balance has good effect in improving the quality of plastic parts.