Interior spaces were found with attempts of previous repairs. The ladder was found removed and epoxy resin was used on the crack. There was also a cut and re-welding on the transverse frame. Technical team assembles the cofferdam. Diving team fits and secures the cofferdam underwater. The area is being waterproofed – creating dry environment in order for Dye Penetrant Inspection (Penetrant Testing – PT) to take place to check surface breaking defects.
PT reveals the length of the crack: 650mm which extends up to the beginning of the vessels curve (not only on the vessel’s flat area). Adjustment of the overall repair based on the new data. Diving team removes the cofferdam. After meeting of all parties concerned (PSOMAKARA technical team, class surveyor and ultrasonic specialist surveyor) repair plan is being decided regarding the actions on the interior spaces and the dimensions of the insert plate.
Cofferdam is being adjusted to the new findings and is reconstructed in a curved shape, based on the vessel’s curve. Preparation of the insert plate. Interior cutting of the transverse frame. Diving team installs the refabricated cofferdam securing it by welding clamping screws. Waterproofing the area – Dry environment is being created. Defected plate is being cropped. Edge preparation of : Shell plating and insert plate. Insert plate was fitted by welding (one pass). Welding is being tested successfully. All aforementioned sequence of actions is being approved by class surveyor.
After extensive tests of the insert plate, full penetration welding took place. The transverse frame was cut from side to side. New frame was constructed and fitted in position by spot welding. Full penetration welding on the transverse frame. Installation of a new ladder. Diving team removes the cofferdam. Welding seams were grinded underwater and were covered with underwater epoxy resin (plastic steel) in order to protect the welding from corrosion. NDT surveyor inspected the insert plate welding and results revealed zero (0) errors. Welding seams found in good condition; no defects were observed.