Comparison of Different Cooling Systems in Plastic Injection Molding

Year 2022, Volume: 34 Issue: 3, 472 - 478, 30.09.2022

Oğuz Girit

https://doi.org/10.7240/jeps.1168047

Abstract

Injection molding is preferred for plastic products due to its high efficiency. However, one of the most important factors after injection is the cooling of the part. Therefore, the cooling process considers being an essential part of the total molding time. Generally, the cooling process in plastic injection molds is done by circulating the cooling liquid through the holes opened in the radial and axial direction on the mold. However, in cases where the cooling is not at the wanted level, the efficiency is increased by placing high thermal conductivity coefficients materials in the molds. With the development of manufacturing methods, conformal cooling systems with cooling channels that follow the molded part geometry have emerged as an alternative to this method. However, this is an expensive method, and studies are ongoing. In this study, the mold cooling times were analyzed and compared with the help of the MoldFlow analysis program on a sample part with a conventional cooling system, as a result of placing a conformal cooling system and a material (insert) with a high thermal conductivity coefficient in the mold.

Keywords

Plastic Injection, Conformal Cooling Channels, Cooling of Plastic Injection Molding, Analysis of Mold Cooling Times

Plastik Enjeksiyon Kalıplamada Farklı Soğutma Sistemlerinin Karşılaştırılması

Abstract

Enjeksiyon kalıplama, plastik ürünler için yüksek verimlilik sebebiyle tercih edilmektedir. Enjeksiyon sonrasında en önemli unsurlardan birisi de parçanın soğutulmasıdır. Soğutma işlemi, toplam kalıplama süresinin önemli kısmını oluşturmaktadır. Genellikle plastik enjeksiyon kalıplarında soğutma işlemi kalıp üzerine radyal ve eksenel yönde açılan deliklerden soğutma sıvısı dolaştırılması ile yapılır fakat soğumanın istenilen düzeyde olmaması durumlarında kalıplara ısı iletkenlik kat sayısı yüksek olan malzemeler yerleştirilerek verim arttırılmaya çalışılır. İmalat yöntemlerinin gelişmesiyle bu metoda alternatif olarak kalıplanan parça geometrisini takip eden soğutma kanallarına sahip olan şekil uyumlu (konformal) soğutma sistemleri ortaya çıkmıştır. Ancak bu pahalı bir yöntemdir ve üzerinde çalışmalar devam etmektedir. Bu çalışmada, klasik soğutma sistemine sahip ve üretimi devam eden örnek bir parçada MoldFlow analiz programı yardımı ile klasik soğutma sistemi, şekil uyumlu (konformal) soğutma sistemi ve kalıba ısı iletkenlik katsayısı yüksek olan bir malzeme (insert) yerleştirilmesi sonucunda kalıp soğutma sürelerinin analizleri yapılarak karşılaştırılmıştır.

Keywords

Plastik Enjeksiyon, Konformal Soğutma Kanalları, Plastik Enjeksiyonda Soğutma, Kalıp Soğutma Sürelerinin Analizi

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