Comparison of Coolant Flow Strategies for Conformal Cooling Channels in Plastic Injection Molding

Öz

In order to increase the production speed and improve product quality in plastic injection molding, more efficient cooling is required for conformal cooling channels. In this study, the cooling efficiency of the conformal channels with spiral, zigzag and parallel flow strategies designed by a systematic design method and straight cooling channels in plastic injection molds were investigated. For this purpose, numerical cooling and warp analyzes were performed and the effects of cooling channels on the cycle time and warpage on the plastic part were determined. With the use of a conformal cooling channels instead of a linear channel, the cooling time has been reduced by up to 51% and the amount of distortion up to 25%. The shortest cycle time was obtained in the spiral-shaped channel and the lowest warpage was obtained with the zigzag-shaped channel. Plastic injection molds with spiral and linear cooling channels were manufactured, production tests were made and the experimental results obtained were compared with the analysis results. It has been observed that the numerical and experimental results are compatible with each other.

Anahtar Kelimeler

• Conformal cooling channels
• plastic part warping
• cooling time

Proje Numarası

07/2018-08

Plastik Enjeksiyon Kalıplamada Şekil Uyumlu Soğutma Kanalları için Soğutma Sıvısı Akış Stratejilerinin Karşılaştırılması

Öz

Plastik enjeksiyon kalıplamada üretim hızının artırılması ve ürün kalitesinin iyileştirilmesi amacıyla daha etkin soğutmanın gerçekleştirilebilmesi için şekil uyumlu soğutma kanallarına ihtiyaç duyulmaktadır. Bu çalışmada sistematik bir tasarım metodu ile tasarlanmış spiral, zikzak ve paralel akış hatlarına sahip şekil uyumlu ve düz soğutma kanallarının plastik enjeksiyon kalıplarındaki soğutma etkinlikleri incelenmiştir. Bu amaçla sayısal olarak soğuma ve çarpılma analizleri yapılarak tasarlanan soğutma kanallarının çevrim süresine ve plastik parça üzerindeki çarpılmaya etkileri belirlenmeye çalışılmıştır. Doğrusal kanal yerine şekil uyumlu soğutma kanalı kullanımı ile soğutma süresi %51 ve çarpılma miktarı %25 seviyesine kadar düşüş sağlanmıştır. Şekil uyumlu soğutma kanalları arasında en kısa çevrim süresi spiral formlu kanalda, en düşük çarpılma ise zikzak formlu kanalda elde edilmiştir. Spiral ve doğrusal formlu soğutma kanalına sahip plastik enjeksiyon kalıpları imal edilerek baskı denemeleri yapılmış ve elde edilen deneysel sonuçlar analiz sonuçları ile karşılaştırılmıştır. Sayısal ve deneysel sonuçların birbiri ile uyumlu oldukları görülmüştür.

Anahtar Kelimeler

• Şekil uyumlu soğutma kanalları
• plastik parçalarda çarpılma
• soğutma süresi

Destekleyen Kurum

Gazi Üniversitesi Bilimsel Araştırma Projeleri

Proje Numarası

07/2018-08

Teşekkür

Bu araştırmaya sağladığı destekten dolayı Gazi Üniversitesi Bilimsel Araştırma Projeleri’ne (BAP) teşekkür ederiz.

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