Effect of Welding Current and Electrode Polarity on Weld Bead Geometry and Shape Relationships in Gravity-Assisted Mechanized Contact Shielded Metal Arc Welding

The paper reports how welding current and electrode polarity affect on weld bead geometry and shape relationships in a gravity-assisted SMAW process. An air-hardening MFH 350 electrode was used. Various weld bead geometry parameters, i.e., bead height, bead penetration, bead width, and shape relationships, i.e., weld reinforcement form factor, weld penetration shape factor, percent dilution, and linear heat input, have been recorded and computed. A gravity-assisted mechanized setup, fabricated in the welding research laboratory was used for continuous mechanized contact welding. The mechanization fully eliminated the effect of the welder’s skill on the melting rate and the BG and SR. The melting rate and hence the welding speed of the bead on plate deposition were varied by varying the welding current. The welding current was varied from 120 to 180 amperes. The whole experiment was conducted with DCEN and DCEP.