ガラスインサート金型によるランナー分岐部流動挙動の解析
Visual Analysis of Melt Flow Behavior in a Split Runner Portion Using a Glass-Inserted Mold
横井秀俊・村田泰彦・長谷元弘
Yokoi, Hidetoshi / Murata, Yasuhiko / Nagaya, Motohiro
On molded products which are manufactured in a multi-cavity mold, the part weight scatter between molded products and short-shots become problems. In this paper, we have attempted to analyze the melt flow behavior inside the runner of a three cavity mold by utilizing a Glass-Inserted Mold. The results obtained through the visual analysis are summarized below.
(1) The flow front advance velocity after the flow front passes through the split runner portion becomes almost constant under various molding conditions except at low injection rates and various molding materials.
(2) The time when the flow front reaches each cavity depends on the flow front shape at the split runner portion.
(3) The flow front shape at the split runner portion dose not depend on the injection rate, but depends on the presence of filler and the filler shape. As the content and the aspect ratio of the filler increase, the flow front sticks out in the flow direction.
(4) The flow front shape at the split runner portion does not depend on the die swell ratio of the molding material, but depends on the filler orientation and the cohesion force acting between fillers.
Key words: Injection molding / Visual analysis / Glass-inserted mold / Split runner portion / Filler orientation