Sealing system for ship's propeller shaft - has emergency sealing system which operates if main system fails

摘要

The ship's propeller is driven by a shaft (4) which passes through an opening (3) in the stern of the ship. The inflow of water (W) is normally prevented by the main sealing system (6) which consists of a stationary ring (6c) which is pressed by water pressure against a rotating ring (6a) which is mounted on the shaft bearing bush. An emergency sealing system is provided by soft packing rings (14) which can be axially comprssed by the axial movement of a ring (13). The periphery of the ring has an acme screw thread (13b) which engages a matching thread (11b) in the fixed housing (11). In the event of a failure of the main sealing system, hydraulic or pneumatic pressure is applied to a linear actuator (15) whicvh rotates the ring (13). The screw thread (11b, 13b) causes the sleeve to move axially and compress the packing rings (14). USE/ADVANTAGE - Sealing system for ship's propeller shaft. Has an emergency seal which becomes effective if the main sealing system fails.