Underwater rudder repair in the Shetland Islands
Hydrex received an enquiry for a rudder repair on a 120-meter trawler. The ship was operating off the coast of the Shetland Islands when a defect occurred on its flap rudder, making it difficult to navigate safely. They immediately mobilized a diver/technician team to the vessel’s location in Lerwick.
A comprehensive inspection revealed that all bolts connecting the rudder flap to the link pin were broken. As a result, the rudder flap had come loose. This made it impossible to correctly position the flap, which in turn made steering difficult. To keep on sailing without a repair posed a great risk as there was a real chance that the damage would get worse. Securing the rudder flap was the only possible underwater solution.
During this inspection exact measurements were taken. Combined with drawings received from the OEM, this gave the team all the information necessary to fabricate eight stiffeners.
The rudder and its flap were then put in the neutral position. Four stiffeners were placed on each side of the rudder, securing the flap to it. The plates were welded underwater by the Hydrex divers. Next the sliding pin was also secured with welding plates. A steering test was successfully performed, concluding the repair.
The ship had a well calibrated rudder again. Because of the remote location of the vessel there was no suitable drydock close by. By immediately mobilizing a team to the Shetland Islands to carry out a temporary repair, Hydrex made it possible for the owner to sail his vessel safely to a drydock of his choice in the Netherlands.