Reduction of Undercuts in Fillet Welded Joints Using Taguchi Optimization Method

Joseph Achebo^1*, Sule Salisu²

¹Department of Production Engineering, University of Benin, Benin, Nigeria.
²Department of Mechanical Engineering, Petroleum Training Institute, Effurun, Nigeria.

DOI: 10.4236/jmmce.2015.33020                

Abstract

This project work focuses on the reduction of weld undercuts using the Taguchi method. The phenomenon of weld undercuts constitutes a major problem for the welding industry. When undercuts occur, and particularly when such cuts are deep, it has a negative impact on the weld as it lowers the integrity and quality of the weldment. Therefore, efforts are made globally to reduce the depth of such weld undercuts to the barest minimum. Several optimization methods have been adopted; however, in this study, the Taguchi method is applied. “The smaller the better components” of the Taguchi method is applied. From the results obtained from applying this Taguchi method, the optimum process parameters obtained are A₂-B₁-C₂, which are a voltage of 20 V, a current of 180 A, and a welding speed of 130 mm/s, required to form an undercut of 0.03 mm. Whereas the existing process parameters used by the company are A₁-B₃-C, which make an undercut to a depth of 0.09 mm. It is concluded that the use of Taguchi method has been able to reduce the depth of undercut as shown in this study. A step-by-step approach is presented in the study.

Keywords

Bead Geometry, Fillet Weld, Process Parameters, Taguchi Method, Weld Undercut

Conflicts of Interest

The authors declare no conflicts of interest.

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