We were contacted by the representative of a 163-meter roro vessel to carry out a crack repair during the ship’s stop in Zeebrugge. The operation was carried out swiftly during the Pentecost weekend in May.
A team of Hydrex diver/welders travelled from our Headquarters in Antwerp to Zeebrugge with all the required equipment. Because our fast response centers have a large stock of state-of-the-art equipment ready, mobilization for smaller operations like this can be almost immediately.
When the work area was declared gas free, our divers started the operation with an inspection of the damaged area and this on both sides of the hull. The crack was located in the engine room ballast tank under a frame. The repair started with the cleaning of the waterside of the damaged area. This allowed the team to take the exact measurement of the crack: 600 mm on the outside. Next a blank was installed over the area. The diver/technicians could then perform work on the crack inside the engine room without water ingress.
The team then removed the frames, bulkheads and a cement box to get access to the crack. Inside the engine room it measured 700 mm. To prevent it from spreading, crack arrests were drilled at its extremities. Next our diver/technicians ground out the crack over its entire length. It was then filled with our class approved full penetration welding.
When the crack had been filled, ultrasonic testing was carried out by and independent tester. The repair was approved by the surveyor and the bulkheads and frames were reinstalled. Finally the blank was removed from the waterside of the crack.
As a result of this temporary repair the owner of the vessel does not have to go off schedule for an emergency visit to drydock, but can make arrangements for a follow up repair at a more convenient time and location.