Study of Porosity Location in Fresh Water Wet Welds

The objective of this work was to determine for particular water depth, the optimum current ranges in terms of best porosity location. Pores located at the top part of each weld bead were generally eliminated through re-melting by the next weld bead. This finding was consistent in fresh water wet welds on ASTM A36 steel using three commercial electrodes: E6013, E7018 and E7024 grades. Two depth levels were studied, 50 and 100 meters. A gravity feed welding system was used in a hyperbaric chamber of 200 m pressure capability. Through visual analysis and with help of a computer software, the optimal weld parameters for each electrode and depth regarding pore location were determined. Additionally, it was observed that porosity increases with increasing current and depth. Similar to welding in seawater, it was also verified that the E6013 electrodes presented greater arc stability and produced the best beads, while the E7018 electrodes did not produce good results. The E7024 electrode exhibited easy arc opening and reopening but did not present good stability. Finally, it was observed that the optimal current range reduced as depth increases.