Not really, they are only used for stripping. Here’s a video of one running on air in a shop. It is a Japanese built unit still in production.
Yes, example if the dearator level fell there were lots of things to think about in a hurry before the shit hit the fan. I loved steam. It was as you aptly described it a symphony. Everyone had to know how to pay their part, sometimes with only one gauge to go by but it was their piece of the music. I worked in a coal fired traveling grate coal plant for a bit before I went back to sea. Earned my ME there literally and figuratively. When you can’t cut off the heat for an hour it makes one humble. Also makes you appreciate the valve turners that know their business.
LOL, yeah, like how fast could you reach the feedpump and reset the overspeed trip without killing yourself!
1 Like
In my notes, have a question about feed water regulators. I found 2 kinds in my books. One was an inclined tube within a tube, which seemed to depend on heat transfer between the tubes to work. The other one worked by thermal expansion of a bar in the steam drum. I never heard of either one before, so (maybe wrongly) I answered with something familiar from controls class.
WTF don’t I have water? Where’s my damn condensate? Desal pump die? Oh geezus. Fun times !
1 Like
Feedwater is controlled by water level as a percent of full drum [full drum like empty drum is bad] measured by level probes or even floats on low pressure systems, feed water inlet flow rate and steam flow rate. That’s a simple 3 element control system.
yea, the stripper pump was much like this but i was thinking of the steam powered pump that moved the crude, i think they were like 7,000 hp !! the shaft from the pump (in engine room) passed thru a bulkhead to the pump room, the steam power plant was actually not very big, like a big dish washer or something and probably ran on aux. steam (600psi) but i’m not sure about that.
The thing about steam is not the pressure, it’s the heat differential. Pressure is only needed to get the heat you need because water boils at 212F under sea level conditions, that’s not that hot. Don’t let it evaporate and it gets hotter. The heat moving is what does the work. Auxiliary steam at 600 psi is pretty hot around 460F or so and can do a lot of work.
I can’t remember the horsepower (if I ever knew) but when discharging and all pumps were online, the boiler load was very close to what he had when steaming underway. It always amazed me how much power was consumed offloading. The pump turbines were much larger than any dishwasher I’ve ever seen. A lot noisier as well.
Old tanker I was on had four 600 hp cargo pump turbines that were geared down and then shafted into the pumproom.
That 2400 hp was a lot less efficient than propulsion hp because they were impulse-only turbines in the intrest of compact size and they were also atmospheric condensing.
Between them, the stripping pumps running and the ballast pump which was also an atmospheric condensing turbine (I forget the hp on that one) the boilers were being fired as if we were going a bit more than half ahead.
Yup. When I sailed on steamships, I felt like an engineer. Moving to diesels, well, I felt like a mechanic and baby sitter. . . still better than most jobs, but not the same.
2 Likes
i’ve had some steam experience but not enuff to be a steam eng. // my experience was that steam was comparatively maintenance free compared to being a ‘mechanic’ on diesel/diesel electric. your comment cmakin is unique and i’m sure gives many engineers a reason to pause !! I believe steam has nearly reached the peak of it’s development as it’s been in use so long and so much research as a result has been done on it but who knows, with the other tech, since there is so much to it, development will prob continue for a long while.
To me what cmakin and Steamer said made perfect sense. Steamer mentioned steam is a symphony which is as good of a description as I have heard. Everything is related and must work together as one to achieve proper efficiency and reliability. It is a different game entirely from a motor plant. Temperatures, pressures at various stages in the process must be monitored . You must monitor trends and think ahead. Automation only does so much with a steam plant. One must have a good knowledge of thermodynamics and fluid flow dynamics as they are not theories but practicalities in a steam plant. Motor plants are exponentially simpler. One would have to experience the difference to truly understand. I have a couple of friends who became nuclear control room operators, we talked over the years and understood each other. Had my experience been only with motor plants I’m sure we would not have had a clue what the other was speaking of. On the other hand my nuke buddies didn’t know squat about their back up diesels except they were advertised to work if needed. 
2 Likes
The OLD Maine Maritime Academy training ship "STATE OF MAINE (EX Navy Hospital Ship COMFORT), had a steam piston feed water pump. Hearing that old thing hiss and bang was reassuring and told us that feed water was indeed being pumped into the old boilers.
The big two-strokes are no steam plants but they still need a lot of continuous monitoring and adjustment to run properly in this era of wildly variant fuels and cylinder lubes, with everything continually riding the razor’s edge between premature wear and excessive fuel/lubes consumption, and incompatible bunkers around every corner. There’s a lot of thinking and planning going on with those operations and maintenance programs the way they’re run today, beyond parts changing, and the companies definitely expect every one of the remote monitoring or control systems to be used to save a buck.
Wish I’d been in a time or place to get any steam time though, everywhere I have been I have just missed it. I think I have a week.
But compared to the symphony of steam are a busker playing two finger chords.
steam symphonies within steam symphonies.
The steam vs motor discussion reminds me of the celestial nav discussion on the deck side.
How the sextant wizards once used their magic and now it’s just a dumb ass mate following a line on a screen. I think the old time second mate might be surprised at how much skill and effort it takes to make sure that dumb ass mate always has a line on the screen to follow.
Same on the eng side I think. I used to meet the steam second eng after the mid-watch in the officers lounge or mess. I was surprised at how little they knew what was happening outside their little world.
1 Like
Not really, most of us hold both steam and motor with plenty of time on each. The discussion is the differences between the modes, not a claim one is better or requires more skill. It is an appreciation of the art.
The two chord busker can make beautiful music but it still isn’t a symphony of many instruments.
Operating a steam plant makes the engineer an intimate component of the plant. It is far more satisfying than pushing paper around and checking off boxes on the do lists.
A mate who is an artist with a sextant knows what I am saying, he gets more than just a position out of the process.
3 Likes
If that were true, I’d have mentors at work I could go to to ask about my exam questions. I don’t know anyone with a steam ticket, and the only ones with steam time are Americans (who had a trip on a steam-powered training vessel when they were cadets) or instructors (who haven’t had a steam ticket for decades). Having you all as resource is a treasure.
1 Like