While the book "Turbine Power", by Walter Simpson (published by Kalmbach Media), does not go into why various railroads in the US in general, and the Great Northern in particular, did not buy into the idea of using STEL or GTEL locomotives, it does answer the technical questions that arose in the replies to the orginal poster. Well worth a read.
In most cases it was the price differential between lower cost bunker C oil and higher priced diesel oil that tipped the hat in favour of trying out GTEL powered locomotives. Reduction of that price differential due to increases in the cost of Bunker C, maintenance issues and the low fuel efficiency of gas turbines eventually did them in, some faster than others.
From this article:
https://en.wikipedia.org/wiki/Fuel_oil#Bunker_fuel
There appear to be three bunker grades: A, B, and C.--from lightest to heaviest.
It would be quite a reach to get all the way to "M".
Ed
timzDunno whether "it turns out" means she said Bunker M didn't exist, or it so turned out after her book.
I do get the idea that UP conducted more careful analysis of cost-effective treatment methods than described, and I find the idea of eliminating ash as a specific component of heavy fuel to be both a way to decrease overall locomotive operating cost and improve reliability, while retaining the ability to contract aggressively for lower-cost fuel. It might be interesting to see if there were experiments to burn Bunker B or C in industrial gas turbines during the comparable period, and if so how the fuel was 'contracted for' and treated at various points before combustion.
OvermodActually, Don pointed out that Cinthia Priest said "Bunker M" didn't exist
In any case, "Bunker M" made it into the Cyc, and some fuel that wasn't plain Bunker C did exist, whatever it was called.
Erik_Mag VGN Jess Bunker C was $1.45/Bl in the 1950's; not sure what Diesel was.-FYI I've seen prices of $0.10/gal quoted for RR use, or $4.20/bbl, so there would have been a slight cost advantage.
VGN Jess Bunker C was $1.45/Bl in the 1950's; not sure what Diesel was.-FYI
Bunker C was $1.45/Bl in the 1950's; not sure what Diesel was.-FYI
I've seen prices of $0.10/gal quoted for RR use, or $4.20/bbl, so there would have been a slight cost advantage.
Bunker C being one-third the price seems like more than just a slight price advantage. Plus there is a BTU advantage to the heavy oil.
Diesel is about 138000 BTU/gal. Bunker C is about 153000 BTU/gal
While many of us, including myself use the term "bunker fuel" to refer to a heavy grade like No. 5 or No. 6 fuel oil, and then we assume it is a specific fraction of consistent quality, I have a sneaking suspicion that the residual fuel actually contained whatever the refinery had left over, and that its quality could vary widely from batch to batch.
No wonder UP wanted it filtered, and I'll bet that steam locomotives handled the impurities a lot better than the turbines.
Greetings from Alberta
-an Articulate Malcontent
timzBut Don Strack says Bunker M didn't actually exist
The 1956 Cyc says UP's turbines burned Bunker M, which was Bunker C that had been "cleaned and strained to remove soda ash." But Don Strack says Bunker M didn't actually exist
Union Pacific, Bunker 'C' (utahrails.net)
Rwy Age for 20 Sept 1954 says UP had started running turbines Green River to Laramie and was planning to extend to Cheyenne "at an early date".
Rwy Age 15 Oct 1956 says UP gave one turbine a 24000-gal tender in November 1955 and started running it Ogden-Omaha. Said it could run Ogden to Omaha and back to Cheyenne on one tenderful of fuel -- wonder if that means they hadn't installed fuel facilities east of Cheyenne.
VGN JessAs noted previously, steam turbines return power much lower than GTELs so comparing apples-oranges re: GN?????
VGN JessAny thoughts on why UP would not have been content with buying standard production diesels and coupling them together in order to achieve the required horsepower?
UP was famous for using what could be enormous consists of small first-generation diesel units, taking advantage of the ability of MU control (the most I recall from an article was 17). This represented an enormous capital investment in contemporary dollars, and a great amount of unnecessary metal and duplication of parts, many of them fragile or prone to failure.
So UP, over the years, experimented with all sorts of ways to reduce costs, including the promise (which turned out unfulfilled for a few reasons) that gas turbines with vastly fewer and simpler moving parts and the ability to develop high horsepower to weight would be suited to railroad service.
Had the free-piston gasifier approach been commercialized by Hamilton, or Lima-Hamilton, or Baldwin-Lima-Hamilton as expected, UP would have been a prime customer -- ghastly noise or not! -- and I believe they were actively interested in the stillborn FG9.
Thanks for the responses. though not too much on GN's sprurning of GTELs, the discussions were very illuminating though as to GTEL's in general!!
GTEL 57 was one of the original production turbines, emphtically not a Veranda. Propane testing was done in southern California, Lee's book having a picture of the refueling station in the LA area - clean burning propane would have been a plus as air pollution was a concern back then. (Our family house in Windsor Hills was built in 1950 and had a bcakyard trash incinerator that we were prohibited from using when we lived there 1955-58.)
Bunker C fuel capacity was 7200 gallons on the first production turbines and only prototype #50 spent much time running without a fuel tender.
TrainOrders has a link to the part of Don Strack's coverage of the turbines that covers #57. I learned a couple of things from this -- one of them that you can't access a link from TrainOrders on an iPhone running iOS 14...
https://www.trainorders.com/discussion/read.php?11,4214417
Conversion experiment was very early (1953) and short-lived (about 6 months) so no, not an answer UP or anyone else cared about. The fuel tender actually had its own GATX number. The locomotive was converted right back to be able to use Bunker B heavy, so those economics were still good enough. Running gear from these was reused under U50Bs, which (for GEs of that era) were not bad locomotives.
It seems to me there was propane experimentation on diesels, either cofired with diesel fuel or using diesel as an ignition and firing or reaction promoter. Can't find that now.
I suspect the electrically heated heavy tanks were not converted and the locomotive was run entirely from the pressurized tender the whole time of the test.…
Wikipedia says the propane turbine was the 57 -- maybe Don Strack's site can confirm that.
Maybe he's got the UP turbine diagram -- wonder how much fuel they carried before they got tenders. 6000+ gallons? Did they stay west of Green River until they got tenders?
Pretty sure it was a 'veranda' turbine. [EDIT: It was surely not; it was one of the original single-end types; memory can be lousy.] MTH modeled it, which ought to be a source to find more specific details. Very cheap propane would be a must... as, I suspect, would be turbines already built.
Overmod 7j43k Perhaps they were not adequately impressed when they used the GN steam turbines in 1943. Ed has a slight typo in that it's "GE" not GN. They could also in a sense have been called UP locomotives because they were painted for that railroad and toured extensively for publicity. Two units of 2500 nominal hp apiece, full condensing at very high pressure. They were interesting but underpowered for their size and weight, and were returned by UP rather briskly -- they were sent to GN as a wartime expediency thing, if I remember the story correctly. According to one account I read, the GN crews worked out or figured how to work around most of the bugs and 'shortcomings', but according to another account the units ran for a few weeks but were then returned to GE when maintenance was required. Note that there is almost no resemblance of these locomotives to any gas turbine UP ran, other than in using generated DC going to traction motors. (Not much resemblance to the coal turbine, either!) GN personnel would likely remember this if assessing gas-turbine designs later...
7j43k Perhaps they were not adequately impressed when they used the GN steam turbines in 1943.
Ed has a slight typo in that it's "GE" not GN. They could also in a sense have been called UP locomotives because they were painted for that railroad and toured extensively for publicity.
Two units of 2500 nominal hp apiece, full condensing at very high pressure. They were interesting but underpowered for their size and weight, and were returned by UP rather briskly -- they were sent to GN as a wartime expediency thing, if I remember the story correctly. According to one account I read, the GN crews worked out or figured how to work around most of the bugs and 'shortcomings', but according to another account the units ran for a few weeks but were then returned to GE when maintenance was required.
Note that there is almost no resemblance of these locomotives to any gas turbine UP ran, other than in using generated DC going to traction motors. (Not much resemblance to the coal turbine, either!) GN personnel would likely remember this if assessing gas-turbine designs later...
Yes, GE.
I believe they were returned to GE by UP, hence not UP locos anymore. On the GN (not surprisingly), they were painted in a simpler scheme.
They ran 14 round trips for GN--not an astounding contribution to the war effort. Also, FT's started showing up on GN shortly afterwards.
GN had undoubtedly ordered and been expecting the FT's, so the GE's were temporary placeholders. They COULD have impressed GN management; they apparently did not.
I remember reading of successful tests using propane in Union Pacific's turbines in 1950's era issues of Trains.
Not sure exactly when, so it may of been one of their 1st generation turbines rather than the later and more powerful Big Blows.
Another question might be... Did UP and GE ever trial a Big Blow fired with LPG instead of heavy fuel oil?
The heavier oils also generally had higher sulfur content, which is corrosive to metals.
timzBut probably that heavier fuel wasn't "bunker" fuel, whatever that is?
Reading between the lines and looking at experience of a couple of the big players in oil-fired steam, one big difference between "Bunker C" and heavier cuts of #5 was the reduction of mineral and other contaminants, not just the asphaltic content. This is inherent in the discussion of 'ashing' in the UP report, but it becomes much more important in the context of EMD injectors. It would be much better in all likelihood to run heavy oil through a separate injection system and not expose the delicate components in the fuel path, but there is no easy way to get one into a typical EMD 2-stroke power assembly as the drive to the latter is mechanical and it occupies the only real position, between the four valves, that a heavy-oil injector could produce a good spray pattern.
I surmise that UP did not use any of that California crude that was heavy in vanadium. I'd suspect that the same general mechanisms at work to damage superheater elements and the like would happily affect '50s-era gas-turbine blading, and perhaps internal-combustion piston engines.
SD70DudeDidn't UP also modify a large number of EMD units to burn bunker fuel?
But probably that heavier fuel wasn't "bunker" fuel, whatever that is?
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