View Full Version : Most Powerful Steam Engine Ever Built?

10-25-2006, 12:19 AM
I'm a newbie to the forum, so this may be common knowledge. What do you think is the most powerful steam engine ever built?

Forrest Addy
10-25-2006, 12:26 AM
The base load coal plants are probably getting close to a million HP.

10-25-2006, 01:30 AM
Hey Shaidorsi;
What do you mean by "steam engines" ? Just reciprocating engines, or do you include turbines ? Do you mean locomotives, or marine engines or stationary engines. A few marine plants are over 10,000 HP. Steam would almost certainly be a turbine plant, probably multi-unit too.
If you mean any type of steam power, Forrest Addey is right. Electric power plants are pretty much the most powerful steam plants around. Near Vancouver, there is the Burrard Thermal Plant. 5 units at 150 megawatts & 1 unit at 175 megawatts. Combustion Engineering boilers, (1100 psig steam at some 1050 deg. F. two stages of reheat.) English Electric alternators & excitation. I can't remember who built the turbines... (Convert that to HP based on 746 watts/HP...) This is a small natural gas fired plant....Some coal burning plants I've worked at, eg. Sundance & Genesee in Alberta are bigger, as are nuke plants like Bruce, Pickering & Pt. LePreau (NB Power, New Brunswick; the only Candu plant I've ever worked on.) A Candu reactor is just a furnace that "burns" neutrons....the problem is the radiation & the radioactive waste .
Just my view...

10-25-2006, 03:24 AM
Biggest coal-fired station in the UK is Drax at 4000MW, from 6 turbine sets.

That's nearly 900 000 hp per set.


ISTR UK companies have supplied bigger sets to China.


10-25-2006, 10:20 PM
Do you recall who the maker of the turbines was at the Dax power plant, or for export to China ? Parsons, Westinghouse, Metropolitan-Vickers (they built the turbines at Burrard Thermal Plant here in Vacouver. Are they still in business or a division of ABB ???)
It seems standard technology now in the large thermal plant field to pulverize & blow the coal for combustion. (Combustion Eng-Raymond pulverizers...?) Does the Dax g/s use low sulphur coal or use a sulphur reducing process ?
900,000 HP is pretty impressive. Some torque available there. Makes the huge 100,000 some-odd HP Diesel Union/ Sulzer engine look puny.
I'm impressed, but I'd like to see the shop where the forging for the turbine shaft & discs was done. Also the lathe for turning that shaft....No more machines like that in Canada, to my knowledge. There were a handful in the 1950's & 60's. Gone to scrap or offshore now, I guess.
So it goes;

10-25-2006, 11:22 PM
If your talking Steam locomotives, that depends. The Big Boy was not the most powerful, although it seamed to be the best rounded one, in terms of traction effort, HP, and top speed. There were others with MORE HP, Or Higher top speeds, or More tractive effort.

10-25-2006, 11:57 PM
Some of those piston steam engines are so big that one revolution of it could displace as much sewage as a small city generates in one day.

10-26-2006, 03:01 AM
Do you recall who the maker of the turbines was at the Dax power plant, or for export to China ? Parsons, Westinghouse, Metropolitan-Vickers (they built the turbines at Burrard Thermal Plant here in Vacouver. Are they still in business or a division of ABB ???)

It was, AFAIR, the Trafford Park (Manchester), formerly Metropolitan Vickers, plant of GEC which built the sets for China. They're now part of Alsthom (French) since the GEC board completely lost the plot trying to make big investments in things they didn't really understand.

Not sure who built the Drax stuff, probably the same guys, it shouldn't be too hard to find out.


10-27-2006, 08:50 PM
What I had in mind was the SSME, Space Shuttle Main Engine. The fuel is Liquid Hydrogen and Liquid Oxygen, producing very superheated steam at 6000F. Constant Loss, Single Stroke to Orbit. At max power one engine produces 512,000 lb of constant thrust, at the drawbar, if you will, straight up. That is roughly equivelant to a bit over 12,000,000 hp! There are three SSME's on the shuttle for about 37,000,000 hp at full chat. Must be quite a ride. I wonder what that would do to a dragstrip. It is somewhat humbling to realize that we are still in the steam age of space exploration. Actually I think the turbopumps that supply the fuel are the real technological wonders.


10-27-2006, 11:37 PM
Yes, let's hear more about those turbopumps. What drives them? At one time I heard they were little more than windshield wiper motors-

I've always thought they were basically the heart of the engines. No fuel delivery, no thrust. Minor pump malfunction, large problem, big boom!

I suppose the analogy to the steam engine, and the one power stroke, makes that a pretty long throw. Is that oversquare or what?

10-28-2006, 01:14 AM
The LH2 is used to cool the nozzles and then the boiling LH2 drives the pumps. I don't know for sure but they must spin them up at first electrically or with compressed gas of some sort.

Undersquare you mean. ;)