Arc characterization study for submerged arc welding of HSLA (API X80) steel

The load bearing capacity of weld is highly influenced by the mode of metal transfer which in turn is dependent on welding current and arc voltage. This paper presents the results of V-I (voltage-current) transient investigation carried out for Submerged arc welding (SAW) of API X80 steel at three different levels of heat input (20 kJ/cm; 25 kJ/cm; 27 kJ/cm). Statistical analysis and Probability density distribution (PDD) curves of recorded V-I transient data are presented for arc voltage as well as welding current. Through this study, an attempt has been made to correlate PDD curves with the metal transfer characteristic of the welding arc. Work described in this paper paves the way to provide a feedback to achieve the online monitoring and automatic control of the weld quality.