How many RPM's does an average cruise ship propeller spin at?

Question

And what is the diamter of an average cruise ship prop?

Answer 1

Large propellers on ships typically rotate between 70 and 120 rpm. If the propeller spins faster there are cavitation issues and greater efficiency losses. The ENGINES can rotate in the thousands of RPM range, but a reduction gear is equipped to "step down" the rotational speed to the propeller.
Ship propellers can be 25' or more in diameter.

However, a cruise ship is not necessarily a typical ship.
On a cruise ship it's very likely that the propeller is not a standard prop, but an Azipod type thruster. These thrusters can be rotated in any HORIZONTAL direction (it can spin 360 degress, but can't "tilt" to push up or down) so a regular rudder isn't needed.
The rpm range will be similar to a typical ship's - that's just the range large propellers operate best in. The diameter will be slightly smaller than that of a fixed propeller though. This is mainly because azimuth thrusters are installed in groups - there will be more than one prop delivering power, so each prop can be smaller.
Look at the links below (and google "azipod" if you'd like) for more info about azimuth thrusters.

Answer 2

Cruise Ship Propeller

Answer 3

You're asking about a very complex things. The number, type, diameter, RPMs of ship propellers very by great extent. First of all you have to specify what kind of ship do you mean? Is it big or rather small? What kind of engine it has? Steam turbines or Diesel engine? How much props? One, two, three?

I could only say that the ship props could be from 0,5 m till 6 and more meres in diameter. Rotation speed can range from about 60 RPM till 2000-3000 RPM.

For instance a ship with one slow going main diesel engine and about 150 m in length has a prop of 5 m in diameter rotating at full speed at about 60 RPM.

Answer 4

RE:
How many RPM's does an average cruise ship propeller spin at?
And what is the diamter of an average cruise ship prop?