Seal for ship propulsion screw shaft - has flexible circular sealing lip rings preventing sea-water entry

摘要

The seal for a rotating shaft is used esp. for a ship propulsion screw shaft bearing tube. Pressurised medium is introduced into sealing elements between shaft and the sealing housing for one sided sealing. The screw shafts of large ships are reliably sealed against penetration of seawater without pollution and the contact between sliding components is ensured without use of lubricating oil. The sealing elements form an annular gap (10) for the outlet of the pressurised medium and the outlet and area of the gap is directed towards the medium to be kept out. This annular gap is formed as a circular nozzle with an elastic material wall. Several sealing rings are used to form a number of circular nozzles.