- 學位論文
高穴數射出成型之流動平衡分析研究
Study on the simulation and experiment of inbalanced flow of multi-cavity products
摘要
精密塑膠製品在考量模具開發成本及高產能的需求，常需搭配高穴數模具及良好的成型穩定性。由於各模穴因模具加工誤差，以及成型過程中受剪切效應與成形條件所影響，易造成流動不平衡的現象，也因各模穴充填不均而致使不同模穴成型品的品質差異。本研究採用Moldflow CAE軟體，針對一模192穴進行模擬分析。模具構造為三板式模具，流道佈置為H型非幾何平衡流道。CAE網格類型採用3D實體網格，分別針對幾何平衡流道區(16模穴)、非幾何平衡流道區(24模穴)、以及整模的四分之ㄧ區(48模穴)進行充填分析。調整方式則以變更流道截面尺寸進行模擬分析，並利用模擬分析完成後的最佳流道設計值進行模具開發，並藉由實際射出的流道來驗證高模穴的模流分析準確性。結果顯示流道設計變更後，幾何平衡流道區的秒差由0.4 ms改善為0.1 ms，非幾何平衡流道區的秒差由1.1 ms改善為0.1 ms，整模的四分之ㄧ區的秒差由1.2 ms改善為0.3 ms，充填結果更加接近平衡。以實際射出驗證後，可得設計變更後的充填相較於設計變更前有顯著改善。
並列摘要
As considering the cost of mold for precise plastic products and high capacity requirement, it often needs to be used with multi-cavity molds and good molding stability. Because of the inside of each cavity will occur imbalanced flow due to the mold machining error or the cutting effects in the molding process, the filling of each cavity becomes uneven and the temperature and pressure can not be completely consistent, thereby also leads to each mold cavity quality different in the molding process. In this study, we use three-plate mold to make actual injection for verifying the analytic results of multi-cavity mold flow and focus on the adjustment of flow balance by the layout of 192 cavity with H-type balance runner and changing the cross-sectional area of the flow channel. We use Moldflow CAE software to analyze flow (filling) process. Because of the symmetry of the flow channel, we adopt a quarter models to analyze. The setting of mesh type is 3D mesh, and we select “ Flow ” as our analysis type. When we interpret the results, this study determines it is whether in line with actual situation according to flow similarity, filling time and maximum filling pressure. From our analysis results, it can significantly reduce the maximum filling pressure and the in-cavity pressure of the mold by the change of design parameters, and obviously reduces the situation of the mold life shortening due to template warpage caused by excessive injection pressure. This change of design parameters can make the flow more balanced, and improve molding stability, and can effectively improve the yield rate in the production process.