Specialty vessels require unique methods of repair to keep them in service and on location. One such vessel is a specialized dynamically positioning offshore loading and offloading system for tankers. Since this vessel is purpose built for a very specific operation offshore, repair facilities were unavailable at the vessels current location to support the repair of the critical azimuthing thrusters. Considering the critical nature of this equipment, the Original Equipment Manufacturer (OEM) together with the vessel’s operators approached Subsea Global Solutions to develop an innovative method to overhaul the thrusters in a completely dry environment in accordance with the OEM’s requirements. Utilizing a proven process of repair already applied to Semi-Submersible rigs around the world by Subsea Global Solutions a specialized collapsible Hyperbaric cofferdam was designed and built by Subsea Global Solutions. With a full compliment of structural, weld and mechanical engineers on staff fully employed by Subsea Global Solutions, the specialized hyperbaric cofferdam was engineered and fabricated in the European office of Subsea Global Solutions. In parallel to this engineering and fabrication project, the operations team worked together with the Original Equipment Manufacturer to develop an installation specific time line and repair procedure for the overhaul of the three dynamically positioning azimuthing thrusters.
One-by-one, the expert diver / technicians of Subsea Global Solutions performed the entire 5 year maintenance of the azimuthing thrusters underwater in a dry hyperbaric environment. This service included the replacement of the main shaft seal, all controllable pitch propeller blade palm seals, steering seal inspection and replacement as needed as well as critical inspection and maintenance to the propellers and other running gear. All work was performed by OEM trained and certified diver / technicians who received unique thruster service training at the OEM’s training academy. As the only OEM recommended global diving contractor, Subsea Global Solutions personnel enjoy the opportunity to receive OEM service engineer training and certification just like the OEM’s service personnel. With this specialized training and skilled personnel, OEM authorized and warranted repairs were performed by Subsea Global Solutions together with the Original Equipment Manufacturer.
With thrusters freshly overhauled, the dynamically positioning offshore loading / unloading station left Europe for it’s next location in South America. Next time Subsea Global Solutions sees the vessel will be at it’s permanent offshore location. Subsea Global Solutions, your trusted resource for unrivaled service.
Sometimes the impossible is made possible by just applying what you already know in a different form and fashion. Subsea Global Solutions had the challenge to extract an entire stabilizer fin together with the Crux (Joint Connection) this past month on a cruise vessel that needed to maintain its schedule on a European Cruise. Recognizing the critical nature of this repair, coupled with the challenging rigging to maneuver over 30 metric tons of fin and crux to the surface, Subsea Global Solutions developed a repair procedure and time line to execute this repair based on years of experience extracting ships equipment underwater. By extracting the damaged stabilizer system with the vessel afloat, this allowed the Original Equipment Manufacturer to make the necessary critical repairs before the next schedule wet dock period in the fall later this year.
Once the client contacted Subsea Global Solutions, a visit on board was performed by the engineering team to assess the in-board as well as out-board particulars of this specific stabilizer fin system. Since the entire stabilizer fin and crux were planned to be removed for repair, it required specialized systems and a detailed process of repair to blank off the crux mating surfaces from the in-board side of the vessel so that rigging of the fin and crux could be performed just like in the dry dock; outboard of the vessel. With critical vessel details now obtained from the on board visit experts from Subsea Global Solutions engineering department met with the Original Equipment Manufacturer to detail out a step by step, port-by-port time line and process of repair. Once reviewed and approved, the team went to work.
Following the vessel from port to port, the diver / technicians of Subsea Global Solutions prepared the stabilizer system for extraction. This included all inboard preparations under the supervision of the Original Equipment Manufacturer together with preparing the outboard side for heavy rigging. By utilizing certified diver / welders certified to Subsea Global Solutions‘ “A” class wet welding procedures, load rated pad eyes were effectively welded to the ship’s hull to support the execution of the extraction. With all inboard and outboard preparations completed, “extraction day” arrived. With a little over 48 hours in port, the stabilizer fin and crux assembly was extracted and brought to the surface with out fail. This incorporated specialized rigging techniques and buoyancy control to “float” the unit to the surface in a controlled and safe fashion. Once extracted, the system was swiftly packaged and sent to the Original Equipment Manufacturer for overhaul so that it maybe installed later this year.
This was the first time a stabilizer fin and crux was ever removed on a vessel still afloat. With expertise and engineering resources in house, a complete repair procedure and time line was developed. With this information the vessel management made the decision to keep the vessel in service and continue to generate revenue. By performing unrivaled service, we are our customer’s trusted partners. We remain available to support your needs at any time. Big or small, your problem is our solution!