| 摘要 |
PURPOSE:To effectively perform corrosion resistance in the wide range of a casing by fitting a sacrifical electrode electrochemically baser than the casing to the underwater part of a supporting member of a propeller which is electrically conducted to the casing immersed underwater. CONSTITUTION:A propeller shaft 21 is supported to a casing 17 immersed underwater with a ball bearing 26 and a plain bearing 29 made of metal and electrically conducted thereto. A propeller cap 19 combined with a sacrifical electrode is provided to the rear part of propellers 18 fitted to the propeller shaft 21. This propeller cap 19 is constituted of both a mandrel part 19a made of brass screwed to the propeller shaft 21 and an anode part 19b consisting of zinc electrochemically baser than the casing 17 made of aluminum alloy. The sacrifical electrode is separated from the casing 17 and a wide region can be made corrosion resistant. Further deterioration of propellant function of a ship is not caused thereby and the exchange thereof at a time of wastage is made easy. |
