Application of Response Surface Methodology to Predict Arc Length of Tig Mild Steel Welds

Abstract

TIG welding finds its application in aviation, marine and automobile
industries. To ensure the safety of lives and properties, weld quality
has continuously been experiencing improvement over the years. The
arc length is the space measurement between the welding torch and
the work piece during welding and this in turn affect the welder’s
comfortability as well as the weld product. This research study was
carried out to optimize and predict the arc length in Tungsten inert
gas welding using response surface methodology. The central
composite design matrix was employed to collect data from the set of
experiment. The samples were cut from mild steel plate, measuring
60mm x 40mm x 10mm. From the result, a model possessing an RSquared value of 92% "Predicted R-Squared” value of 77% which is
in reasonable agreement with the "Adj R-Squared" value of 85%.
Adequate precision measuring the signal to noise ratio of 10.649
indicating adequate signal were observed. An optimal settings of
input parameters; welding current 130Amps, welding voltage
20.94V, and welding speed 0.48m/s resulting in a minimized arc
length of 2.0044mm was obtained.