State-of-the-art and trends of development in underwater wet welding and NDT inspection

Huge amount of underwater structures that are used in oil and gas production, as well as increasing intensity of naval transport presents the technological cornerstone of the economical development and strategic issues. On the other hand, almost daily we are witnesses in various cases of environmental pollution that are caused by means of improper usage of these installations or inadequate maintenance. Maintenance of these structures or eventual repairs under the water line demands application of appropriate technologies such are underwater welding and inspection. Due to high safety risks, great importance and responsibility in performing of these activities is on the highly trained and educated human resources, including divers and organization team on the surface. Specially designed equipment is necessary for successful accomplishing of practical tasks. In global aspects investigations for improvement and application of underwater welding and NDT techniques have been highly intense through recent decade. In Croatia, this field is very important, due to great intensity of oil transport and gas production in the Adriatic sea. Based on that, there are several projects about underwater activities that are conducted within Department of Welded Structures, Faculty of mechanical engineering and naval architecture at University of Zagreb. In this article, main issues about problems in underwater welding and inspection are presented. Beside that, current state-of-the-art in underwater welding and inspection in Croatia is given, as well as possible alternatives in development.