Problems encountered in underwater welding and remedies- a review

Abstract

Wet underwater welding has proved to be the most suitable solution for underwater repairs and fabrication works. However, number of difficulties are faced that are specifically depicted in the testing and analysis of welds obtained while welded underwater. Major issues that are faced include immediate contact of workpiece with water leading to severe quenching effect, hydrogen diffusion due to dissociation of water which causes hydrogen induced cracking, arc instability, porosity in welds due to infused gases, loss of alloying elements leading to degradation of mechanical properties and microstructure of weld metal, increased hardness of HAZ and associated cracking. Since its inception during world war I, number of researchers have worked on finding the way out to control the harmful effects due to problems encountered during underwater welding. This paper discusses the experimental works conducted for detailing the problems encountered and the solutions suggested by researchers to overcome them. Controlling the input parameters during welding, addition of alloying elements into the electrode coating and multipass welding are the suggested solutions for obtaining desired characteristics in the welds.