**4.6 Main effect plot for bead width**

The main effect plot will help to determine the optimum value of the input parameter. Main effect plot is obtained for S/N ratio and mean for bead width by using Minitab 18 statistical software [8]. The main effect plot will represent significant the level of each input parameter as shown in **Figures 1** and **2**. Optimum value to obtained optimum bead width with their significant level is given in **Table 18**.


**Experiment no. Process parameter**

*DOI: http://dx.doi.org/10.5772/intechopen.93974*

**Table 12.**

**Signal-tonoise ratio**

Larger is better

Nominal is best

Smaller is better

**Table 13.** *S/N ratio.*

**175**

*Orthogonal array actual value.*

**The goal of the experiment Data**

Target the response and you want to base the signal-to-noise ratio on standard deviations only

Maximize the response Positive �10log <sup>1</sup>

Minimize the response Non-negative with a

**characteristics**

Positive, zero, or negative

target value of zero

**Signal-to-noise ratio formulas**

*n*

<sup>i</sup>¼<sup>0</sup>̄yi

�10log.[<sup>P</sup>

�10log.1/n [ P <sup>i</sup>¼<sup>0</sup>yi2]

2/s2 ]

[ P *<sup>i</sup>*¼01*=y*i2]

**P B FT**

*Application of Taguchi Method in Optimization of Pulsed TIG Welding Process Parameter*
