Effect of Chemistry of Weld Metal in Submerged Arc Welding

Abstract

The submerged arc welding process is the most widely used arc welding process for joining thick plates and pipes. The features that distinguishing submerged arc welding from other arc welding process is graduallyfusible material termed as flux. The flux used in submerged arc welding contributes a major part (above 50%) towards the total welding cost. The properties of weld metal have been found to be dependent upon flux-electrode-base metal-composition on welding parameters. Flux and filler metal play a central role in ascertaining the property of weld metal. In the present work, the effect of operating arc voltage, welding current, welding speed and nozzle distance on flux consumption and chemical composition of carbon and silicon has been studied.A Mathematical model was developed from data generated using two level-half factorial technique. The experiment is conducted as per the design matrix. Design Expert software 7 is used in order to (i) the designing of a set of experiments for adequate and reliable measurement of the true mean response of interest (ii) the determining of mathematical model with best fits (iii) finding the optimum set of experimental factors that produces maximum or minimum value of response and (iv) representing the direct effects of procedure variables on the flux utilization, current and silicon through two dimensional graphs. It was observed that the flux utilization decrease with an increase in wire feed rate and its welding speed. The flux utilizationan increase with an increase in arc voltage. The effect of constant tip to work distance has in significant effect on flux utilization. Carbon percentage an increase with an increase in arc voltage and welding speed. Carbon percentage reduce with raise in welding current. Silicon percentage decrease as an increase in current and voltage.