Tornalamada Ortogonal Kesme İçin Tırlama Titreşimi Ve Kararlılığın Lineer Analizi

Year 2006, Volume: 19 Issue: 2, 89 - 108, 31.12.2006

Sezan Orak , Erol Türkeş

Abstract

 Takım tezgahlarında maksimum talaş kaldırma hızının artırılması, yüksek talaş genişliği ve işleme hızları gerektirmektedir. Bu gereksinimlerin aşırı zorlanması ise, kesme hızının değişimine neden olarak titreşim meydana getirir. Bu durum ise düşük parça işleme hassasiyeti, yüksek işleme kuvvetleri ve aşınma gibi bir çok problemlere sebep olmaktadır. Kesici takım ve iş parçası arasındaki dinamik etkileşimden dolayı kendi kendini besleyen tırlama titreşimi meydana gelmektedir. Bu çalışmada, tornalamada ortogonal kesme için tırlama tahmini yapılmıştır. Bir serbestlik dereceli kesme modelinin lineer analizi yapılarak kararlılığı analitik olarak incelenmiştir. Sistemin lineer analizi, yönlendirilmiş transfer fonksiyonu (OTF) ve τ dekompozisyon formlarının Nyquist kriterine uygulanmasıyla yapılmıştır. Her iki yaklaşımdan elde edilen tırlama frekansı tahminleri, modal analizle elde edilen sonuçlarla ve kesme testleriyle karşılaştırılmıştır. Her iki f

Keywords

Takım tezgahları, Tornalama, Tırlama, Kararlılık analizi..

Lınear Analysıs Of Chatter Vıbratıon And Stabılıty For Orthogonal Cuttıng In Turnın

Abstract

Increasing of the Maximum Metal Removal Rate (MMRR) in machine tools requires high metal removing widths  and machining speeds. Rigorous forcing of these two conditions cause changes in the cutting speed which result in cutting tool vibrations. This phenomenon leads to such problems as detrimental effects on the machined surface finish, decreasing of the machining efficiency, adverse effects on the work surface finish, high machining forces, tool wear and, shortening of the tool life. Due to dynamic interactions between cutting tool and workpiece, self-excited chatter vibration occurs. In the current study, chatter prediction was made for orthogonal cutting in turning operations. A linear analysis of the Single Degree of Freedom (SDOF) model was performed by applying Oriented Transfer Function (OTF) and τ decomposition forms to Nyquist criteria. Chatter frequency predictions obtained from both approaches were compared to the results obtained from modal analysis and cutting tests. The required computer programs  were written by using MATLAB

Keywords

Machine tools, Turning, Chatter, Stability analysis..

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