:: Artigo completo: https://doi.org/10.1007/s40194-025-02095-2
Abstract
This work investigates the application of pulsed current in underwater wet welding with a covered stick electrode. The underwater wet welding technique is widely employed in the offshore industry to support repair operations, highlighting the need for researchers to examine its operational characteristics and address its inherent challenges. shielded metal arc welding (SMAW) is preferred due to its cost-effectiveness, acceptable weld quality, and ease of use. This study specifically involves performing wet welds using a specialized power source that enables electronic control of the welding current, applying pulsed modulation while maintaining a consistent mean current in DC-mode. Welds were simulated at depths of 0.3 m and 30 m, using both direct and reverse polarity. The key findings reveal that increasing the pulse frequency enhances the operational stability of the oxyrutile stick electrode, as indicated by reduced arc voltage fluctuation and increased arc stiffness in DCEP polarity at a depth of 30 m. Additionally, the melting rate and weld bead penetration were positively correlated with the Root-Mean-Square current (IRMS). Lower pulse frequencies and higher welding current amplitudes led to a higher melting rate, attributed to an increased Joule effect.
Keywords: Pulsed current; Arc stability; Hydrostatic pressure; Wet welding; Melting rate; Weld bead penetration
Referência:
CASTELLANOS-GONZALEZ, O.M., MORENO-URIBE, A.M., SANCHEZ-LOBO, E.J.; ARIAS, A. R.; SILVA, R. H. G.; HASSEL, T.. Pulsed shielded metal arc welding: a new approach for underwater applications. Weld World (2025). https://doi.org/10.1007/s40194-025-02095-2