Effect of Process Parameters on Weld Spatter in Robotic Welding

Abstract

This research deals with the investigation of a real-life industrial problem of excessive weld spatter produced in an automated welding robot cell using gas metal arc welding process. Spatter generation was attributed to a number of sources including incorrect machine settings, surface contaminants, and erratic wire feeding. Random variation of different welding process parameters such as voltage, wire feed speed, and torch travel angle, affected spatter production, which served as a motivation to embark on a systematic study involving design of experiments. A total of ten most significant parameters were identified through a brainstorming process involving robotic cell operators, section managers, and subject matter experts. Using the selected ten parameters, preliminary experiments were conducted to determine the appropriate operating range for each process parameter that has the most significant impact on weld spatter. An Orthogonal L16 Array from Taguchi’s designs was chosen with four parameters at 4-levels, four parameters at 2-levels, and two parameters were held constant at 1-level. Following the establishment of a defined set of parameters and corresponding ranges of values, a series of designed experiments were conducted to measure the effect of process parameters on weld spatter production. During each designed experiment, six different responses were recorded that included, the weight of wire used, the weight of the weld bead deposited, the mass of spatter collected in a tray, audio signals generated, the spatter particle count using ImageJ, and the quality of the weld bead. The optimal process parameters identified in this study were of practical significance, and as such the recommended parameters were implemented in the industry.