Investigation of cutting parameters effect for minimization of sur face roughness in internal turning

Abstract

NOMENCLATURE R a,n = Surface roughness with new insert R a,u = Surface roughness with slightly used insert η n = Signal to Noise ratio of R a,n Minimizing the surface roughness is one of the primary objectives in most of the machining operations in general and in internal turning in particular. Poor control on the cutting parameters due to long boring bar generates non conforming parts which results in increase in cost and loss of productivity due to rework or scrap. In this study, the Taguchi method is used to minimize the surface roughness by investigating the rake angle effect on surface roughness in boring performed on a CNC lathe. The control parameters included besides tool rake angle were insert nose radius, cutting speed, depth of cut, and feedrate. Slight tool wear was included as a noise factor. Based on Taguchi Orthogonal Array L 18 , a series of experiments were designed and performed on AISI 1018 steel. Analysis of variance, ANOVA, was employed to identify the significant factors affecting the surface roughness and S/N ratio was used to find the optimal cutting combination of the parameters. It was concluded that tool with a high positive rake angle and smaller insert nose radius produced lower surface roughness value in an internal turning operation. It was also concluded that high feedrate and low cutting speed has produced the lowest surface roughness.

Delik içi tornalamada kesici ucun ve delik işleme barasının delik işlemeye etkisi

“…Çelik baranın kullanımı, küçük delik boyları (L/D < 4) için uygun olurken, büyük delik boylarında (L/D > 4) karbür baranın kullanımının daha uygun olabileceği, ayrıca karbür baranın çelik baraya göre titreşimi azalttığı ifade edilmiştir [5,6]. Kesici ucun da, titreşim üzerinde etkili olduğu; [7,8], titreşim sönümlemeli (AVB: Anti Vibration Bar) delik baralarının titreşimi önemli derecede azaltarak delik içi yüzey pürüzlülüğünü iyileştirdiği, karbür baralara göre daha uzun takım ömrüne sahip olduğu, dolayısı ile de daha az maliyetli olabileceği belirtilmiştir [15]- [17]. Bununla birlikte incelenen çalışmalarda, farklı çaplara, malzemelere ve özelliklere sahip delik işleme baraları ile farklı geometrilere, uç yarıçaplarına ve malzemelerine sahip kesici uçların da kullanıldığı görülmüştür.…”

Experimental Investigation of the influence of the Cutting Conditions on the Surface Roughness in Hole turning the SCM400 Steel

“…Muhammad Munawar et al [2] conducted an experimental study on grinding the AISI 1018 steel when changing parameters including the rake angle of the cutter, radius of the cutter nose, cutting speed, feed rate, and cutting depth. Their research has shown that with a knife with a positive rake angle and a small cutter nose radius, the machining surface had a small roughness.…”

Dynamics Analysis of Unbalanced Motorized Spindles Supported on Ball Bearings

“…Due to the complexity of the reliability and performance problems caused by profound high speed effects [1][2][3], the machine tools capable of achieving the high speed cutting were first introduced commercially in 1980s, which lags behind the theory of high speed metal cutting by 50 years [4]. Motorized spindles are the core components of CNC machine tools and greatly improve the cutting speed, while the inevitable unbalance of the spindle system caused by unexpected errors during manufacturing and installation process strongly influences the machining productivity and finish quality of workpieces in high speed operating conditions [5][6][7][8][9][10][11].…”