・ New ship to replace current Koyo Maru, built at MHI’s Shimonoseki Shipyard & Machinery Works and in service since 1998, with handover scheduled for June 2024
・ Vessel has one of the highest pulling capacities in Japan, efficient systems for firefighting on other ships, and SCR system to comply with environmental regulations.

Mitsubishi Shipbuilding Co., Ltd., a Mitsubishi Heavy Industries (MHI) Group company based in Yokohama, today held a christening and launch ceremony for a salvage tug currently being built for Nippon Salvage Co., Ltd. The ceremony took place at the Enoura Plant of MHI’s Shimonoseki Shipyard & Machinery Works in Yamaguchi Prefecture. The vessel, named “Koyo Maru”, is scheduled for handover to Nippon Salvage in June 2024 following completion of outfitting work and sea trials.

The vessel has a length overall (LOA) of 80.6 meters and beam of 15.5 meters, with gross tonnage of approximately 3,000. It will replace the current Koyo Maru, originally constructed at MHI’s Shimonoseki Shipyard & Machinery Works, and which has been in continuous service since 1998. The new vessel has one of the highest pulling capacities (bollard pull) in Japan to respond to large-scale marine accidents, while optimal placement of fire extinguishing equipment such as water cannons, and improved fixed-point holding capacity, provides enhanced efficiency when firefighting on other ships.

The Koyo Maru is also equipped with a selective catalytic reduction (SCR) system to comply with environmental regulations, allowing it to operate in designated areas where nitrogen oxide (NOx) emissions are restricted, such as the coastal waters of the United States and Canada, the North Sea, and the Baltic Sea. Further, the vessel utilizes a new hull form (semi-vertical stem) to improve propulsion performance, and has been designed to allow temporary equipment such as remotely operated vehicles (ROVs) to be mounted on the exposed deck (Note) as necessary, improving workability. Private rooms for supervisors have also been made provided to improve livability.

With the construction of this vessel, Mitsubishi Shipbuilding will contribute to the various salvage activities carried out in seas around the world, as well as environmental conservation. In addition, by building vessels with excellent fuel efficiency and environmental performance, and that contribute to the safety of society, Mitsubishi Shipbuilding aims to provide solutions to the various societal issues facing its customers in Japan and overseas.

Comparison of the New and Current Vessels

(Source: Mitsubishi Heavy Industries)