Rotating arc welding technique is a variant of gas metal arc welding (GMAW) process, in which the wire is rotated at a controlled speed, and in a controlled direction. Rotating arc welding (RAW) is widely employed in the joining of high thickness plates, because of its inherent advantages such as no need of edge preparation, capability to weld in all positions and higher productivity.

In this present investigation, high thick mild steel plates were joined by RAW and the process parameters such as welding current, welding voltage, welding speed, wire feed rate and arc rotating speed were optimized to attain full penetration in square butt joints with narrow heat affected zone.

The responses like bead width, depth of penetration, reinforcement height, weld metal area and heat affected zone areas were measured experimentally. The experiments were conducted based on five factors, five levels central composite design matrix.

The empirical relationships were developed to predict the bead geometry incorporating RAW process parameter. The results indicate that arc voltage had the greater influence on the formation of bead profile.

By increasing the arc voltage, responses such as bead width, reinforcement height, depth of penetration and bead angle increases. This is because higher arc voltage generates more heat input.

Similarly, while increasing the arc rotating speed, reinforcement height, width of heat affected zone and bead angle decreases. This is because of higher arc rotating speed that results in lower heat input.

This article is shared by R. Rajpradeep, S. Malarvizhi, V. Balasubramanian, A. Hafeezur Rahman and V. Balaguru