Naval Engines - Rotate that shaft!

Today we take a quick tour through the primary ways of turning steam into rotation, the ships engines.

Sources:
Naval Reciprocating Engines and Auxiliary Machinery - Barton and Stickne
Naval Engines and Machinery - Barton
A Short History of Naval and Marine Engineering - Smith
U.S. Destroyers: An Illustrated Design History - Friedman
The Steam Turbine - Parsons

[LstEngineer]

I don't know how you handle the pressure of churning out so much content, but I do enjoy that you're always full steam ahead.

[davidbrennan]

One for us “Black Gang” Enginner types.... thanks Drach

Hurrah for Wednesday.

[slytlygufy]

"Stop giggling there in the back." Superb, Sir!

[sagebrushbob]

In my 21 years as a naval engineering chief, I served on ships with steam plants ranging from 200 PSi, to 600 psi, up to 1200 psi and loved all of them. However, I still favor the 1200 psi superheated turbine plants of the 1955-1975 era US destroyers. They were like hot-blooded race horses: a bit finickey and high-maintenance systems, but nothing else had so much power squeezed into such a small space. Changing periscope lights on top of an operating 1200 psi superheated boiler is something that has to be experienced to be believed...

[overboss]

oh boy it's Drach time ladies and gentlemen.

[rachelberkhahn]

Double acting cylinders unlocked!
Turbine reduction gears unlocked!
This tech tree has some head scratcher moments when viewed in retrospect.

[hairy-dairyman]

As a kid, the only family holiday we could afford was going to Echuca in Victoria. Our aunty had a house out of town we could use on her property. It was just big enough for 4 families to have a room each. We would take a ride on the paddle steamers that still run on the murry River. I think it was one of the few times the owner of the steamer had seen 15 kids and 3 fathers all watching his every move, bugging him with questions and not the country as it passed by. It started a mechanical fascination in us kids that has led to three heavy plant mechanics, two farmers that restore old tractors, an electrical engineer, a mechanical engineer, a printing press mechanic, a deep drilling specialist geologist, a jet engineering professor and a hydro power plant maintenance manager. 4 of us are fire-fighters as well. I hope it also led to some proud parents as well.

[riderstrano]

36:53 I can personally attest to this being supremely helpful, as while moving between ports a while back, the fireboat took air into one of its engine’s water cooling lines. This necessitated the shutting down of that engine, but since we have diesel electric drive, we were able to throw a switch on the main board and keep both shafts turning. I might add that we were designed and built with our diesel electric system in 1938

[rvincentsogrub]

Just as I was thinking, "I already watch the Boilers video, The Shells video a while ago... I wonder when Drach is going to made an Engine Video." Then this pops up.

[JessWLStuart]

My Grandfather, who was an engineer aboard USS Iowa in WWII, mentioned the large diesel engines on the Graph Spee caused vibration issues with Graph Spee's rangefinders.

[lloydevans]

A small note about the engines on the Titanic: These were technically quadruple expansion, with the first three expansions happening in cylinders - each engine having one high pressure cylinder, one intermediate pressure cylinder and two low pressure cylinders. There were two of these engines, driving the port and starboard propeller shafts, and both were reversible, though not through a gearbox: Reversing required stopping the engine and then engaging a small "barring engine" to flip the angle of the connecting rods such that when the engine was restarted, the crankshaft would be turning in the opposite direction. The final steam expansion was through a dedicated low pressure turbine, which took steam at around 5 psi (completely useless to any piston engine) and expanded this to almost no pressure at all. This drove the central propeller shaft, which could not be reversed, though engaging it was optional - the steam exiting the two main engines could bypass the turbine altogether and be sent directly to the condenser, albeit wasting any power it could generate and hence making the ship somewhat less efficient as a result.

Interestingly enough, the Titanic and its sister ships were fitted with several smaller high pressure and high speed steam turbines, solely for generating electrical power for lighting, heating, and other "hotel services" aboard. It actually had more generating capacity of this type than was required for normal operations: The extra turbogenerators were reserved for driving emergency bilge pumps and electric winches for lowering lifeboats. As the ship was sinking, some of the engineering crew heroically kept the forward-most boilers stoked up to provide steam pressure to keep the generators going, without which it would have sunk a little quicker (anywhere between 10 and 30 minutes, depending on who you ask), and in all likelihood enabled all of the lifeboats to be launched successfully. Those smaller turbines were probably still spinning away as the ship sank, and took some of the engineers down with it.

[billharm]

FYI... Regarding steam propulsion plant startup time... in the past (distant, USN) I participated in an evolution that went from "cold iron" to "answering bells on all engines" in 34 minutes. We were moving briskly to make it happen (Yes. Operational considerations did require us to get underway ASAP). Stresses due to temperature differentials and rate-of-change of temperature (pretty much the same thing) were our most limiting factors (Yes. We consciously considered such factors during plant evolutions. If you break the plant, the startup time becomes excessive).

[Big_E_Soul_Fragment]

Drach: "Today we take a _quick_ tour...."
Is 44 minutes long.
*[Grabs some snacks]*

[MrFinalresistance]

Last time I was this early, the 2nd Pacific Squadron still had a full supply of binoculars

[ivanstrydom]

I read: ''Rate that shaft.''
And seeing that title on the internest, the first thing that came to mind was ;'' OH MYYY''

16:48 AHH! So my judgement was correct!!

[sorakagodess]

i just love how u can enter a video about naval engines and end it knowing about so many others interesting things, and with a certain depth at that

[TakeMeToChurchill]

Excellent as always!

Minor nitpick: when talking about double-acting engines you mention that steam is admitted to different sides of the cylinder depending where the cylinder head is. Think you mean “piston” - if the cylinder head’s moving you’ve got other problems!

[theleva]

So, should we wait for video on screws titled "You spin me right round"?

[Axel]

Ah, steam plants. My life for 8 years on a submarine. (As some are aware, but many are not, a nuclear powered ship is simply a traditional steam turbine propulsion plant that replaces fuel oil with a nuclear reactor as the heat input for the boilers)

[MIck-M]

I went to see a Corvette in Australia HMAS Castlemaine (because my grandfather was an officer on its sister ship etc). When they found that out I got an extra cool tour of the engine room and absolutely every pipe and cylinder explained - even the entire start up process and water management systems. It was a thing of beauty for sure. A very special day for me.