Recently, a Hydrex diving team was mobilised to Curaçao to perform large insert repairs on a 190-metre bulker that had developed several holes in its hull.
Hydrex was contacted by the owner to perform repairs on the hull plating of his vessel in Cuba. To obtain a good overview of the damage it was proposed to first carry out an underwater inspection after which a tailor-made open top cofferdam would be designed and manufactured. Hydrex arranged to carry out the inspection and subsequent repairs in Curaçao close to the headquarters of its local support base. An expert Hydrex technician flew to this location to assist with the inspection, to decide on the equipment that would be needed for the repairs and to take the exact measurements needed by our technical department to design a cofferdam that would conform precisely with the shape of the hull.
While additional Hydrex divers/welders flew to Curacao together with the required lightweight equipment from the company's fast response centre, arrangements were made to have the cofferdam built by a local company which started the construction under the supervision of a Hydrex technician as soon as it received the instructions.
When the open top cofferdam with a height of 4500mm and a width of 5700mm was delivered it was immediately installed onto the hull of the vessel and all water was removed from it, creating a dry underwater area in which to work. A small additional cofferdam was also installed inside the area spanned by the large cofferdam to facilitate the water discharge from the ship. Next the cement boxes, installed by the crew to temporarily stop the leaks, were removed from the inboard side of the hull together with the piping and framework to allow the removal of the two affected areas and the installation of the new inserts from the outside.
One large L-shaped insert plate was installed in two phases covering a total height of 2900mm and a width of 4200mm. This was followed by the fitting of a second plate with a size of 300mm x 600mm. Both inserts were curved in the same way as the cofferdam to fit the rounded shape of the hull.
Ultrasonic testing showed the repair to be successful and five large frames each with a height of over three metres were reinstalled on the inboard side of the hull. Finally the cofferdam was removed, concluding the repairs.
The operation was performed in accordance with Russian Register requirements. Working closely together with its local support base in Curacao, the Hydrex technical department was able to keep the time frame of the repair work to the absolute minimum of only seven days.
For further information contact: