Determination of Volumetric Shrinkage in High Performance Polymers by Mold Flow Analyses

Öz

In today's technology, computer-aided engineering analyzes are used to determine the dimensional errors that may occur in the injection of high-performance advanced polymers and plastic products. In this study, it is proposed to determine the dimensional errors that may occur after product injection with high performance advanced polymers such as PPS (Polypropilen Sulfite) and PK (Polyketone) with different injection temperatures, with the Mold Flow plastic flow analysis program. For this purpose, 18 Mold Flow analyzes planned according to Taguchi experimental design (L9) were conducted. In the analyses, volumetric shrinkage values were obtained by using three injection conditions such as melt temperature, cooling time and runner gate. After the study, it was seen that the most effective injection condition on the dimensional errors caused by volumetric shrinkage was firstly the runner gate and then the melt temperature. As a result, thanks to Mold flow flow analysis, the injection processes of the plastic product can be determined in advance, and significant savings can be achieved on the cost.

Anahtar Kelimeler

• High performance polymers
• Dimensional errors
• Mold Flow analyses.

Yüksek Performanslı Polimerlerde Hacimsel Çekmenin Mold Flow Analizleri ile Belirlenmesi

Öz

Yüksek performanslı ileri polimerler ile plastik ürünlerin basımında oluşabilecek ölçüsel hataların daha önceden belirlenmesinde, günümüz teknolojisinde bilgisayar destekli mühendislik analizlerinden önemli ölçüde yararlanılmaktadır. Bu çalışmada, farklı enjeksiyon sıcaklığına sahip PPS (Polipropilen Sülfit) ve PK (Poliketon) gibi yüksek performanslu ileri polimerler ile ürün basımı sonrasında meydana gelebilecek ölçüsel hataların, Mold Flow plastik analiz programı ile tahmin edilmesi hedeflenmiştir. Bu amaç için Taguchi deneysel tasarıma göre (L9) planlanmış 18 Mold Flow analizi gerçekleştirilmiştir. Analizlerde, eriyik sıcaklığı, soğutma süresi ve yolluk giriş yeri gibi üç enjeksiyon şartı kullanılarak, hacimsel çekme değerleri elde edilmiştir. Çalışma sonrasında, hacimsel çekmeden kaynaklı ölçüsel hatalar üzerinde en etkili enjeksiyon şartının öncelikle yolluk giriş yeri ve sonra da eriyik sıcaklığı olduğu görülmüştür. Sonuç olarak, Mold flow akış analizleri sayesinde plastik ürünün basım süreçleri daha önceden belirlenerek maliyet üzerinde önemli kazançlar sağlanabilir.

Anahtar Kelimeler

• Yüksek performanslı polimerler
• Ölçüsel hatalar
• Moldflow analizleri

Destekleyen Kurum

GÜNEŞ PLASTİK KALIP SANAYİ TİCARET A.Ş.

Teşekkür

Güneş Plastik Kalıp Sanayi A.Ş. ve çalışanlarına teşekkür ederiz

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