Major emergency repairs carried out on two vessels afloat in Dakar

Two vessels with serious hull damage were recently repaired in Dakar, Senegal, demonstrating once again how complex steel repairs can be carried out while ships remain afloat. By mobilizing experienced teams and specialized equipment, Hydrex was able to stabilize damaged structures and carry out permanent repairs without requiring the vessels to enter drydock. 

Both projects involved different types of hull damage and required tailored repair methods. In each case, the work was performed in close cooperation with the vessel’s representatives, classification society surveyors and local partners.

Immediate stabilization of damaged hull plating 
The first intervention involved a tanker that had sustained hull damage and required structural reinforcement. When the team arrived on site, the priority was to stabilize the affected areas and restore the integrity of the hull. 

After mobilizing our team and equipment to Dakar, preparations began immediately. Four steel plates were fabricated locally and prepared for installation while additional personnel and equipment were on the way and arrived shortly afterwards. Because the vessel’s location was accessible only by water, the team worked from a workboat during the operation. 

The four doubler plates had been constructed using exact measurements to follow the contours of the hull plating. They were carefully installed over the damaged areas of the hull and secured with screwdogs to ensure a tight fit. A neoprene sealing layer was applied around the edges before the plates were fully welded in place.Additional brackets were then installed to reinforce the structure and ensure the strength of the repair. Once the welding was completed, the screwdogs were removed and the areas were inspected by the Hydrex divers to confirm the integrity of the installation. 

Permanent insert repairs on LNG carrier 
Shortly afterwards, a second vessel required more extensive structural repairs while anchored in Dakar. The ship had suffered severely deformed and cracked hull plating on the starboard side of a water ballast tank. 

After consultation with the attending classification surveyor, it was decided that the damage would be repaired by installing two permanent insert plates in the vessel’s shell plating. The work was carried out according to the Hydrex class-approved welding procedure.

To create a dry and controlled workspace, the team designed and fabricated two cofferdams that were installed over the damaged sections of the hull. These cofferdams allowed the repair team inside the vessel to safely remove the damaged plating and prepare the area for the new inserts.Prefabricated insert plates were then positioned and welded in place using full penetration welds from inside the vessel. After welding, non-destructive testing was carried out by an independent surveyor to verify the quality of the work. The internal structural frames were subsequently reinstalled and inspected before the cofferdams were removed. 

Complex steel repairs without drydock 
Both projects highlight how serious hull damage can be addressed effectively while vessels remain afloat. By combining underwater operations with internal steel work, Hydrex was able to carry out both temporary reinforcements and permanent structural repairs without requiring a drydock visit.In both of these cases, Hydrex was contacted based on previous positive experiences working with their teams.

Having already seen how they approach complex repairs and cooperate with crews and classification societies, the customers knew they could rely on Hydrex again when new challenges arose. 

Source: Hydrex Underwater Technology