SOĞUK DÖVME KALIPLARINDA ÖMÜR ARTIŞI ELDE ETMEK İÇİN BASKIN HASAR MEKANİZMASININ BELİRLENMESİ

Bu çalışma kapsamında soğuk dövme yöntemiyle üretilen M10x16 konik kafa T50 soketli bağlantı elemanının üretiminde kullanılan soğuk dövme kalıpları ele alınmıştır. Üretim hattında düşük çevrimde kırıldığı tespit edilen zımba adaptörü için detaylı çalışmalar yürütülmüştür. Üretimden alınan hasarlı kalıplar incelenmiş ve sonlu elemanlar yöntemi kullanılarak şekillenme ve kalıp analizi simülasyonları gerçekleştirilmiştir. İlgili çalışmalar göz önünde bulundurularak kalıp tasarımı revize edilmiş ve kalıp ömründe yaklaşık 20 kat iyileşme elde edilmiştir. Revize edilen ve üretimde kullanılmış hasarlı kalıplar için incelemeler tekrarlanmış ve baskın hasar mekanizmasının değiştiği tespit edilmiştir. Yapılan çalışmalar kapsamında, soğuk dövme kalıplarında ömür artışı elde edilmesi için baskın hasar mekanizmasının ortaya çıkarılması ve karşı tedbir alınması gerektiği ve bu döngünün hedeflenen kalıp ömrü elde edilene kadar devam edilmesi gerektiği ortaya konmuştur.

Anahtar Kelimeler:

Soğuk dövme, hasar mekanizmalarının incelenmesi, sonlu elemanlar yöntemi, kalıp gerilme analizi

Determination of Effective Failure Mechanism to Improve Tool Life of Cold Forging Dies

In this study, production tools of cold forged M10x16 conic head fasteners with T50 socket were investigated. Punch adapter, one of the production tools of the investigated fastener, was examined due to early failure observed during production. Failed punch adapters were examined and finite element simulations were carried out. Based on the detailed examination, the design of the punch adaptor was revised and approximately 20 times life enhancement was achieved. The failed punch adaptor after design improvement was re-investigated and it was shown that the effective failure mechanism acting on the punch adaptor was changed. According to investigations carried out in this study, it was shown that tool life enhancement could be obtained by determining the effective failure mechanism and applying countermeasures. This procedure has to be carried out until the target service life is achieved.

Keywords:

Cold forging, failure analysis, finite element method, tool stress analysis,

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