Seal for ship's propeller shaft - has two axially spaced lips controlled by lubricant at pressure greater than water pressure

摘要

The seal for a ship's propellor shaft has two axially spaced lips (6, 7) situated one near and one spaced from the pressure to be excluded. The space (12) next to the shaft and between the lips is connected to a lubricant having a pressure greater than the pressure to be excluded. The back of the one lip (6) is connected at the lubricant pressure so that the higher pressure can dominate the one lip. The back of the other lip is connected to the higher pressure so that the other lip is pressure-balanced and lubricated.