Ship Crankshaft

Look at that.
Wonder what precision it is made to. I'll bet much tighter tolerance than I imagine.

I couldn't tell you.

What exactly is it out of? I'm assuming a (very) large marine diesel - don't even know the displacement, but those things are several stories high and operate at about 90 rpms.

I guess MAN makes some of them; I don't know who else.

Or, is it out of some external-combustion steam engine setup?

Yes, those are the ones. In big container carriers.
I think this one was from Hyundai Heavy Industries. (never knew they made these things).
Only a few companies in the world can make them. A ship engine can last the life of the ship

Sprintcyclist wrote:Yes, those are the ones.  In big container carriers.
I think this one was from Hyundai Heavy Industries. (never knew they made these things).
Only a few companies in the world can make them. A ship engine can last the life of the ship

Now that I think about it, I have heard of Hyundai refitting marine power in cargo ships. As well as building their own ships - shipbuilding is a big part of Hyundai's various businesses.

I'm not so sure they last the lifetime of a ship, although of course they can. But efficiency gains with newer designs have had various ships refitted over their lifetimes - the QEII was converted from steam turbines to a MAN diesel-electric propulsion system - the generator driving an alternator and the current driving electric motors on the prop shafts. I'm not sure that's how most marine installations work - seems to me that I'd read, single, variable-pitch screws were used in most of the ULCC oil tankers, with direct drive.

I could easily be wrong. In the Navy, I was a clerk, not an Engineering guy; and my first ship, with steam turbine propulsion, is now an artificial reef on the ocean floor. My second ship, an aircraft carrier, is nearing the end of its service life - launched in 1981.

Casey Jones wrote:

Sprintcyclist wrote:Yes, those are the ones.  In big container carriers.
I think this one was from Hyundai Heavy Industries. (never knew they made these things).
Only a few companies in the world can make them. A ship engine can last the life of the ship

Now that I think about it, I have heard of Hyundai refitting marine power in cargo ships.  As well as building their own ships - shipbuilding is a big part of Hyundai's various businesses.

I'm not so sure they last the lifetime of a ship, although of course they can.  But efficiency gains with newer designs have had various ships refitted over their lifetimes - the QEII was converted from steam turbines to a MAN diesel-electric propulsion system - the generator driving an alternator and the current driving electric motors on the prop shafts.  I'm not sure that's how most marine installations work - seems to me that I'd read, single, variable-pitch screws were used in most of the ULCC oil tankers, with direct drive.

I could easily be wrong.  In the Navy, I was a clerk, not an Engineering guy; and my first ship, with steam turbine propulsion, is now an artificial reef on the ocean floor.  My second ship, an aircraft carrier, is nearing the end of its service life - launched in 1981.

Ah, thanks, yes, I could see an old inefficient diesel being replaced with a new efficient diesel electric system.
Never knew the generator system set up. Can see that being more controllable. Could give a smoother load on the motor, could make a much smoother running propeller if there is no huge diesel on the end of it.
Not heard of a variable pitch screw either

on a vastly different scale, apparently very old fridges use so much more electricity than newer ones it is economic to replace them even if they are working ok.
Goes against my 'use it till it stops' mindset.

Sprintcyclist wrote:
on a vastly different scale, apparently very old fridges use so much more electricity than newer ones it is economic to replace them even if they are working ok.
Goes against my 'use it till it stops' mindset.

A good mindset.

I HAVE a new refrigerator. Came with my apartment.

A power outage had me plug it into my emergency power inverter - it's computerized and identifies the load draw on it. The refrigerator draws 150 watts when running.

But good god!...is it LOUD!

The whisper-quiet refrigerators of 20 years ago are deader than Elvis. And this matters, since my "kitchen" is just an alcove, one corner, of my apartment's front room. A 3' 6" counter comes out of the wall, containing the kitchen sink, cupboards below, and some counterspace. Not a breakfast bar, since there's no room for seating (legroom) there. Only seating for meals is there in my front-room space. It's very cramped.

But the refrigerator makes it loud in here. And it's running 2/3 of the time. AND, I know from neighbors, those things fail at about three years old.

My understanding they are direct drive, and as mentioned low RPMs. Reverse you stop the engine and restart in the other direction. They are for propulsion only, hotel services are another system.