Abstract - This paper deals with the literature review of various factors that affect the turning operation. Traditionally, Turning is done manually on lathe machine which require constant supervision of operator on lathe machine, or on automated lathe machine which does not require continuous supervision. Such type of automation is called computer numerical control or CNC. In this paper various process parameters like speed, depth of cut, feed, nose radius, etc. are studied. This study will help us in understanding, which parameters is significant parameter for Surface Roughness, Material Removal Rate, Feed Force, Tangential Force, Tool Life, etc.

Index Terms – Taguchi method, S/N ratio, Optimization, Orthogonal array, ANNOVA.

I. INTRODUCTION
The Taguchi method determine the quality characteristics by using loss function. Loss function values are converted to a signal-to-noise (S/N) ratio. S/N ratio is the ratio of the mean to standard deviation. Signal represents the square of mean value of the quality characteristics while noise is the measure of the variability of the characteristics. The S/N ratio characteristic is divided into three categories namely:- Smaller-the-Better: - This category of S/N ratio is selected when the characteristic like circularity, surface roughness, power consumption, etc. are required to minimize. Larger-the-Better: -This case is opposite to the smaller the better case. This category of S/N ratio is selected when objective function is to maximize the characteristic like Material Removal Rate. Nominal-the-Best: - When a specified value is most desired, meaning that neither a smaller-the-better nor a larger-the-better value is desirable.

ANNOVA or Analysis of variance is useful for determining the influence or significance of input parameters. While performing analysis of variance or ANNOVA, Degree of freedom should be considered. The data are used to obtain the F value. The P value i.e. percent contribution shows how much factor influences the machining
Roughness is basically a high frequency, short wavelength component of measured surface. Rough surface usually wear more quickly than smooth surface. Roughness may increase adhesion. Decreasing the roughness of a surface will increase the manufacturing cost. Surface roughness tester is the instruments which measures the surface roughness.

Cutting Forces: - The relative forces in a turning operation are very important parameters in the design of machine tools. The machine tool and its components must be able to withstand these forces any deflections, vibrations or chatter during the operation. There are three principal forces during turning process; Tangential force acts downward on the tool tip allowing the work piece to deflect upward. It supplies the energy required for cutting operation. Feed Force acts in the longitudinal direction. It is called feed force because it is in the feed direction of the tool. This force pushes the tool away from the chuck. Thrust Force acts in the radial direction which tends to push the tool away from the work