The behaviour and performance of stern tube bearings and seals are to some extent interdependent; both must operate under conditions imposed upon them by the propeller, shafting and hull system, determined partly during the construction of the ship but subsequently changed according to the loading of the ship, the speed, sea and climatic conditions. The paper sets out, briefly, some of the failure statistics which confirm that this is one of the less reliable parts of the ship at the present time. Although somewhat interdepenent, it is, however, convenient to consider bearings and seals separately. The criteria for safe operation of the bearing are stated. The effects of clearance, length/diameter ratio, bore configuration, alignment and shaft bending upon oil film thickness, stiffness and damping capacity, are discussed with examples. Some possible palliatives are described. The behaviour of seals is considered, and in particular the effects of pressure and vibration are discussed. Different arrangements of lip seals are described, together with service experience, leading to the concept of complete separation of the water and oil systems. (Wassmann)
Some considerations in the design of sterntube bearings and seals
Einige Betrachtungen zur Auslegung von Wellenaustrittsrohrlagern und -dichtungen
1979
19 Seiten, 17 Bilder, 13 Tabellen, 29 Quellen
Conference paper
English
Sterntube Seals - Is traditional oil-based sterntube seal lubrication on the slippery slope?
Online Contents | 2011
Sterntube seals and plastic bearings - a ship owner's developments and experiences
Tema Archive | 1976
|Cavitation phenomena of sterntube bearings
Engineering Index Backfile | 1966
|Sterntube seals can be fitted alongside
Tema Archive | 1993
Non-polluting sterntube bearing
Tema Archive | 1981