Volvo D11 series, Руководство по установке

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Propeller shaft systems
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Shaft bearings
There are different types of shaft bearings. Choose
the type which suits the application and use. The
shaft bearings could be fitted in a propeller shaft
bracket, front and/or rear end of the stern tube or in a
separate support bearing.
Cutlass bearings
The most common type, especially for medium and
faster boats. The bearing is made of rubber with a
shell of brass. The design of the bearing is to create
a film of water, upon which the propeller shaft floats.
Normal play between shaft and bearing is 0,% of
the shaft diameter. Bearings fitted in, for example,
p-brackets are normally self-lubricated but for bear-
ings in stern tubes is it important to ensure the water
supply.
Metal bearings
Metal bearings are often fitted inside a stern tube or
a separate support bearing and grease lubricated.
They could be combined with grease lubricated shaft
seals.
Bearing boxes
Bearing boxes use ball or roller bearings. The bearing
box can be lubricated with grease or oil. Some bear-
ing boxes can also take an axial thrust.