| 摘要 |
PURPOSE:To prevent leak of oil to the outside of a ship, by a method wherein sea water is sealed by means of magnetic fluid shaft seals, and only oil is sealed by a lip seal in a stern pipe. CONSTITUTION:Magnetic fluid shaft seals 12 are held to a housing 5 by means of a first intermediate ring 7 and a second intermediate ring 8. The seals 12 are situated at an interval in the axial direction of a propeller shaft 1, and the seal is formed with a pair of pole rings 14 and 15, a magnet assembly 16, and magnetic fluid 17. The magnetic fluid seals 12 are situated on the sea side 18, and a lip seal 19, sealing only oil, is situated on the stern pipe 6 side. An air chamber 23 is formed on the side situated facing sea water 18 sealed by the magnetic fluid shaft seals 12, and an air pressure in the air chamber 23 is set to a value slightly higher than that of the sea water 18. |
