Underwater rudder crack repair in South Africa

Hydrex performs repairs on any type of rudder at anchorage or while the vessel is berthed, without interrupting cargo operations. In most cases these repairs are permanent and do not require follow up. In some cases, the repairs are temporary and subject to further action when the ship is next in drydock. This was the case with the operation in Durban.
 
A team of Hydrex diver/welders traveled from our headquarters in Antwerp to Durban where they met up with their local support base. The company has a large global network with state-of-the-art equipment at the ready. This allows them to mobilize for smaller operations like this almost immediate.
 
After arriving on-site, the team set up their equipment while the team leader discussed the scope of work with the superintendent of the ship. The divers then started the underwater operation by cleaning the area around the crack. This allowed them to make a detailed inspection of the affected area.
 
With the measurements taken during this inspection, a complete assessment of the damage could be made. This allowed them to create the best possible repair plan for the problem.
 
The crack was found to be 650-mm in length, covering the weld seam of the starboard side rudder cover plate. The crack was curved over the left top corner of the inspection plate.
 
To prevent the crack from spreading, crack arrests were drilled at its extremities. Next the diver/technicians ground out the crack in a v-shape over its entire length. They also ground the surrounding area. Then a root pass was made in the crack. It was then filled with full penetration welding.
 
As a result of this repair the owner of the vessel did not have to go off schedule for an emergency visit to drydock, but could make arrangements for a follow up repair at a more convenient time and location.