Jones 3D Modeling Club https://www.youtube.com/Jones3DModelingClub
Overmod That's not the Centipedes; what you're looking at is the far more significant Essl modular locomotive (which used 408-engined gensets. each with its own little piece of carbody for the radiators, that could relatively easily be swapped out if they failed a la RDC engines, or fired up as needed for instantaneous HP vs. fuel efficiency). That was the first practical 6000hp single-unit diesel locomotive design, the only real problem being that each 750hp unit was arranged to drive on the single adjacent driver axle, giving both control and slipping issues in that era.
M636C"Mar. 2, 1948 VP James M. Symes rejects Charles D. Young’s suggestion for a highpressure water-tube boiler for the S2 turbine locomotive, as the only way to increase turbine efficiency is to use a forced draft, and no fan can stand up to the damage from fly ash and other abrasives. (VPO)"
We should pause here for a moment. There are two kinds of draft in boiler design, forced draft and induced draft, which have specific technical meaning. Very often in railroad practice you see the former term mistakenly used for the latter implementation, as with what Symes is doing here. Induced draft is upstream of the boiler, and the primary air is pulled through the fire, the radiant section, and the convective passes before being exhausted (either through a draft fan or via nozzle ejection as in a traditional front end). Forced draft involves a sealed firebox, and fan arrangements acting as compressors to provide a positive overpressure (and hence greater mass of available oxygen) in the combustion space. Of course, every little hole or seam in the firebox spews gas and soot all the time, which is why forced draft has been a dubious proposition since the early years of steam-locomotive design when it was first tried.
Now you may notice that the B&W high-pressure watertube boiler proposals that culminated in the locomotive design used in the N&W TE-1) will work nicely with induced draft. But not with the draft induced from the S2-style mechanical turbine, with its relatively high slip at low speed, perhaps not even from the V1's two turbines and Bowes drives.
Symes is likely thinking of some of the experimentation with fan drafting, notably MacFarland's. Fans with enough performance to duplicate the effect of conventional front ends that would 'package' in the room available would either have to turn quickly or be very large, in either case exacerbating the impingement wear of exhaust ash and soot on the blading. (It is illustrative to note the ways the South Africans dealt with this through changes in construction and location, a few years later)
An example of railroad use of forced draft is the Velox boiler (described by Duffy in a rather good Newcomen Society paper) which used a gas-turbine compressor to produce (iirc) about 30psi pressure in the combustion air. You can dramatically reduce the size and weight of plant needed for producing a large mass flow of high-pressure steam. But one has to argue that using an expensive, fragile, high-maintenance turbine as a prerequisite for a relatively low-efficiency Rankine cycle plant is a dubious proposition economically -- and I think the Swiss experience thoroughly bore this out.
The US Navy used forced draft in the Destroyer Escorts from DE 1037 Bronstein onward, up through the Knox class until these became known as Frigates and the next class, the FFG-7 went to gas turbine propulsion. My understanding is that these [Navy boilers] were pressurised boilers, with high pressure air being pumped into the combustion space by blowers well downstream of the combustion.
I believe you mean 'upstream' in this context, e.g. pressurized ahead of the air preheaters, with something like Racer pressure burners themselves fed primary compressed primary air.
Of course, these were all oil fired, but coal firing of a pressurised boiler, possibly using pulverised coal injected into the blower stream should be practical.
I'm not sure that's the word I would use for any mobile pulverized-coal plant as by definition you're pressurizing the entire feed apparatus to get it to work reliably, and any failure is likely to result sooner or later in nice coal-dust explosions (which can propagate at about 0.93c, an effect likely to be implicated in the sinkings of the Lusitania and Britannic) and fires where you do not ever want them. Feeding PC with compressed primary air in the burner is one thing; positive overpressure in the firebox something decidedly different.
Now, I have had quite a bit of fun designing locomotives that use a combination of forced and induced draft; the arrangements at the primary end involving a cellular windbox and active dampers to allow fitting a proper combustion-air preheat arrangement and some 'trim' over the fired areas on a grate, but no more than a couple of psi peak overpressure. Even that is probably overkill for most practical road locomotive applications...
Jones1945Looking at the patent drawing of the Baldwin Centipedes, I really can’t understand how they could approve such “vanguard” design;
That's not the Centipedes; what you're looking at is the far more significant Essl modular locomotive (which used 408-engined gensets. each with its own little piece of carbody for the radiators, that could relatively easily be swapped out if they failed a la RDC engines, or fired up as needed for instantaneous HP vs. fuel efficiency). That was the first practical 6000hp single-unit diesel locomotive design, the only real problem being that each 750hp unit was arranged to drive on the single adjacent driver axle, giving both control and slipping issues in that era.
There have been a couple of articles in Trains with good information on this; the principal problem was that it was even more expensive than the equivalent hp's worth of building-block EMDs ... and that proved more important than the length reduction (this design offering considerably more than a 4-unit FT hp in only about 58' length; see Kiefer's 1947 report for the packaging advantages).
PRR's Centipedes were built with those DeLaVergne tugboat derived engines, taking four of them in two units to match Essl's prospective output. This was considered (by Baldwin and PRR) to be a better capital and maintenance prospect, the engines peaking at only 625rpm with everything overbuilt. (If you argue, consider how R.J. Russell, who ran BP-20s on the Bay Head trains, got normal high acceleration -- he said the ammeter would go into the red and peg, and only come floating down after a minute or so, stop after stop. And PRR only retired those units when it consolidated the number of types of locomotive power after 1963...
M636C ……My understanding is that these were pressurised boilers, with high pressure air being pumped into the combustion space by blowers well downstream of the combustion. Of course, these were all oil fired, but coal firing of a pressurised boiler, possibly using pulverised coal injected into the blower stream should be practical. At least there were no turbine blades to erode, just the water tubes......
Backshop Since nothing happens in a vacuum, what else is happening in the railroad world at this time... Other railroads have dieselized and laid off thousands of employees and closed multiple heavy maintenance facilities. They have also stopped their dependence on the whims of the most powerful labor union of the time (UMW). Even if the PRR gets the duplexes sorted out, so what? Most are for passenger trains, which although they are prestigious, don't make any money. What are you going to do to replace those thousands of H,K,I,M,and L classes worn out from the war. The only reason the Pennsy wasn't swamped by the war was all the steamers not needed by the new electrification. Now, they are antiques.
Since nothing happens in a vacuum, what else is happening in the railroad world at this time... Other railroads have dieselized and laid off thousands of employees and closed multiple heavy maintenance facilities. They have also stopped their dependence on the whims of the most powerful labor union of the time (UMW). Even if the PRR gets the duplexes sorted out, so what? Most are for passenger trains, which although they are prestigious, don't make any money. What are you going to do to replace those thousands of H,K,I,M,and L classes worn out from the war. The only reason the Pennsy wasn't swamped by the war was all the steamers not needed by the new electrification. Now, they are antiques.
rcdryeA key to the diesel transition was the MU building block principal. Once labor agreements allowed MU operation it became possible to build a 6000 HP diesel that could still operate if one of the units went off line. If your 9000 HP turbine drops out, you're in real trouble. PRR's side trip with the Baldwin Centipedes shows how deeply the "Big Engine" mentatlity was embedded in both builders and carriers. Santa Fe's largely unnoticed, but nonetheless groundbreaking decision to order all of its FT units with couplers instead of drawbars hastened the end of steam as much as anything.
“Feb 24, 1948 Charles D. Young writes to James M. Symes calling attention to an article on turbine locomotives in the Feb. 14 issue of Railway Age and suggests inviting Westinghouse Electric Corporation and Babcock & Wilcox to collaborate on a design for a high-pressure water-tube boiler for the Class S2 6-8-6 chassis. (VPO)”"Mar. 2, 1948 VP James M. Symes rejects Charles D. Young’s suggestion for a highpressure water-tube boiler for the S2 turbine locomotive, as the only way to increase turbine efficiency is to use a forced draft, and no fan can stand up to the damage from fly ash and other abrasives. (VPO)"
The US Navy used forced draft in the Destroyer Escorts from DE 1037 Bronstein onward, up through the Knox class until these became known as Frigates and the next class, the FFG-7 went to gas turbine propulsion.
My understanding is that these were pressurised boilers, with high pressure air being pumped into the combustion space by blowers well downstream of the combustion. Of course, these were all oil fired, but coal firing of a pressurised boiler, possibly using pulverised coal injected into the blower stream should be practical. At least there were no turbine blades to erode, just the water tubes...
These installations were very compact for their power, 600psi and 22000 shp in the Bronstein and 1200psi and 35000 shp in the Knox.
Of course the 40000 shp in the FFG-7 from two GE LM2500s was even more compact and not that much less fuel efficient, since you could run on one turbine and extract waste heat for dometic purposes. You could also run on one boiler in the steam ships, of course, but they had only one steam turbine which was a single point of failure.
These ships are about ten to fifteen years later than the rail steam turbines being discussed, but the US Navy is rarely at the forefront of technology (nuclear power excepted).
Peter
A key to the diesel transition was the MU building block principal. Once labor agreements allowed MU operation it became possible to build a 6000 HP diesel that could still operate if one of the units went off line. If your 9000 HP turbine drops out, you're in real trouble. PRR's side trip with the Baldwin Centipedes shows how deeply the "Big Engine" mentatlity was embedded in both builders and carriers. Santa Fe's largely unnoticed, but nonetheless groundbreaking decision to order all of its FT units with couplers instead of drawbars hastened the end of steam as much as anything.
Some patent drawings of the PRR V1 project (9000hp Direct-Drive Steam Turbine Locomotive) from 1946 (source: Google Patents):
Steam Turbine Electric Locomotive Vs Direct-Drive Steam Turbine Locomotive
Overmod ……You can consider whether simple evolutionary improvements, such as better-cast valves, or more complex ones like piston-valve conversions, would have made the engines embarrassingly better just as the economics for any highly-sophisticated steam passenger power were declining radically, and find evidence for politics accordingly……
Overmod As you all probably know, I think practical luxury-bus service was nipped in the bud far too early, essentially starting when Missouri proactively reduced its highway size and axle-load limits. Look at the late Pickwick Nite Coaches, and the later Santa Fe articulateds, to see what interesting rubber-tired alternatives could have been for all those REA city pairs that were becoming uneconomical to serve even with one-man motor trains.
There is nothing wrong with Jeri Ryan...she da bomb!
There was a show where one of her Borg thingies was expiring and would lead to her demise and it appeared she was to be a goner.
She said "adjusting to my abscene will be difficult" ...well heck yeah!
I want that on my headstone.
Rode a lot of trolleys in my day in Hamilton. Was better when it was streetcars. They were stoic and characterless. Drivers hated 'em cause the twin contact was always coming off the overhead and out the door he would go cursing.
Departing from a Diesel bus and reaching the end of the bus just as it pulls away and getting that heat blast followed by all the smelly atmospherics is not something correct for the human condition. ...and of course Murphys Law states the bus won't leave until you are in the correct spot every time.
Miningman Good grief, I'd rather discuss Seven of Nine than buses. Buses suck...and stink.
Good grief, I'd rather discuss Seven of Nine than buses. Buses suck...and stink.
Trolleys don't.
And what's wrong with Voyager? I thought Jeri Ryan did a fine job on that show!
Greetings from Alberta
-an Articulate Malcontent
People wanting to hatchet on H.T. Cover should budget for a vacation in Delaware and spend a couple of days at the Hagley reading his surviving correspondence. They might shut up afterward.
What this likely refers to is the ongoing correction of lateral control vs. suspension that was (still) a significant concern in 1946. Some engines had been 'corrected' with improved equalization and allowance for lateral motion, and could traverse the 'problem areas' e.g. in Pittsburgh station better; these were the ones assigned to Harrisburg-Pittsburgh. The others were kept on the 'racetrack' that was their first best use, etc.
The smoking gun comes sometime in 1948, when the decision is made to take the T1s off the first-class trains (sometimes this is described as 'dieselizing all the first-class trains', but I get the impression the T1 removal was the more important objective) and at about the same time, perhaps linked, the full improvement program is abandoned. You can consider whether simple evolutionary improvements, such as better-cast valves, or more complex ones like piston-valve conversions, would have made the engines embarrassingly better just as the economics for any highly-sophisticated steam passenger power were declining radically, and find evidence for politics accordingly; remember, these guys were looking at very alarming actual statistics, and not the 'fudged' ones that pretended the T1s were hangar queens making only multiples of hundreds of miles a month.
As you all probably know, I think practical luxury-bus service was nipped in the bud far too early, essentially starting when Missouri proactively reduced its highway size and axle-load limits. Look at the late Pickwick Nite Coaches, and the later Santa Fe articulateds, to see what interesting rubber-tired alternatives could have been for all those REA city pairs that were becoming uneconomical to serve even with one-man motor trains.
Miningman Whoa! Lots of stuff here...... Jones @6:25 post about the T1's. Well they had Flash Gordon and Buck Rogers almost 4 years before the production models rolled out and extensive testing during that time. I recall the tests on the static bed at Altoona and the published results and subsequent reporting of breaking every record and all time bests of water and coal consumption coupled with astronomical horsepower ratings. The best thing ever. Reading that nonsense you can just picture the authors stating things like " no, not 8 times, that's too much, makes us look bad...lets say 4 times, yeah thats good, they will buy that". Show trial, kangaroo court. 3) Wow on the working model S2. For about ten minutes I felt like "I have done nothing this good in my whole life" but I snapped out of it.
Whoa! Lots of stuff here......
Jones @6:25 post about the T1's. Well they had Flash Gordon and Buck Rogers almost 4 years before the production models rolled out and extensive testing during that time. I recall the tests on the static bed at Altoona and the published results and subsequent reporting of breaking every record and all time bests of water and coal consumption coupled with astronomical horsepower ratings. The best thing ever.
Reading that nonsense you can just picture the authors stating things like " no, not 8 times, that's too much, makes us look bad...lets say 4 times, yeah thats good, they will buy that". Show trial, kangaroo court.
3) Wow on the working model S2. For about ten minutes I felt like "I have done nothing this good in my whole life" but I snapped out of it.
Whoa! Lots of stuff here.
1) Overmod-- R.H.Smith recommended the purchase of 5 more. I can only assume he was qualified enough to make a sane decision. Perhaps Mr Smith looked at it as a political decision based on a tip and nod to the coal industry, as you say, not a large % of N&W's fleet. The minus and the minus make a plus sort of thing. My point about Saunders has little to do with his decision on its desirability but what was coming his way probably stock price wise or perhaps something shorter term. Of all the railroads N&W could have run their A's and others up to the mid 70's assuming they can appeal or seek exception and stretch things out say 3 years or so after the Clean Air Act.
2) Jones @6:25 post about the T1's. Well they had Flash Gordon and Buck Rogers almost 4 years before the production models rolled out and extensive testing during that time. I recall the tests on the static bed at Altoona and the published results and subsequent reporting of breaking every record and all time bests of water and coal consumption coupled with astronomical horsepower ratings. The best thing ever.
I regret that I can’t join the discussion since I am not familiar with steam turbine locomotive except PRR S2, even though I am really interested in this new topic for me. Anyway, I just found this record from PRR Chronology. I would like to put it here for the record：
"Mar. 12, 1952
Board reviews the status of the T1's, all 52 of which are now out of service, with only 19 stored in good running order; note that the maintenance costs are 2.5 times that of Class K4s; heavy running repairs are almost 3 times as great; T1's are 4 times as costly to operate as diesels; slipperiness did not work with PRR’s grades; decides they are to be disposed of as soon as the equipment trust obligations are paid off. (VPO)"
This thing actually sound like a trial to me. If T1 was really that bad, why spent tons of money to design, to test, and to build them in the first place? It was not the first time Baldwin and PRR building a new class of engine. If this was the judgement directly came from the heads of PRR, they were just making themselves looks like a world class fool.
MiningmanNo money in it for him personally for approving of 5 turbines.
Yeah, but be sure to read 'Tale of a Turbine' (which is actually titled "Rails Remembered, volume 4") very carefully, and tell me if you would pay what it would cost to replicate that thing in that quantity.
Remember that the TE-1 program spans the development era of practical second-generation diesels, including the realization at GE that a great deal more horsepower could be developed out of the basic Cooper-Bessemer engine architecture. A 4500hp steam-turbine electric is competitive with little GP7s or F units. It's a poor alternative to two 2400hp six-motor Alcos. And I have to suspect that any other TM than a Westinghouse hexapole would be cooked at least as badly in line service, at least as quickly, as Mr. Newton documented.
I am by no means a fan of Stuart Saunders (who reminds me of an evil American cousin of Sir Topham Hatt) but with respect to that turkey he was right.
Stuart Saunders...crook, criminal, vandal, scumbag, American Taliban.
The warden in Shawshank Redemtion.
No money in it for him personally for approving of 5 turbines.
I've known people like him and it's always puzzling how these terrible weasel people get into positions of power.
Without admitting any culpability, Mr. Saunders was among a group of former directors and officers who later contributed to a $12 million settlement to end litigation brought by shareholders of the bankrupt railroad. The lawsuits accused the railroad's management of dereliction of duty and of responsibility for issuing false financial statements and misleading proxy material over a period of years. Graduate of Harvard Law School
BigJimThen you will have to show me as I sure have never seen anything about "65 mph" being a target for the "Jawn Henry".
There are multiple pieces of documentation that establish BLH touted the design which became the TE-1 as being capable of "65mph". I suspect this might be related to the kind of diesel-electric claim to "120mph gearing" where the speed is limited by the constant horsepower to well below what the traction motors could be spun up to -- but with the promise of external combustion to eliminate the constant-horsepower issue.
Unlike the C&O M-1, the TE-1 was not intended to be a passenger locomotive. I quote from Mr. Newton (pg. 713); "the N&W's Class A locomotives were able to haul 175 fully loaded coal cars at 40 MPH, which was fast enough (my emphasis).
But this ignores the other uses of the TE-1 as a replacement for the class A as well as the compounds: there were plenty of uses in fast freight, mail, and probably express where the A's speed of ... about 65 mph ... was necessary and expected. You may recall that Mr. Newton was referring to a train of 175 coal hoppers, not exactly the poster child consist for high speed either physically or economically -- yes, 40mph was 'fast enough'. But you may also recall that the TE-1 was intended as a more economical replacement for ALL N&W freight steam going forward, and just as there is little point in C&O operating an Allegheny well below the peak of its horsepower curve, there would be little point in reducing N&W to the equivalent of a one-speed railroad with comparatively fragile turbines that cost multiple times what an A did. Especially when the Baldwin design with the span-bolstered diesel trimount trucks had specifically been promoted as a locomotive capable of all services N&W anticipated.
Further reading will show that R.H. Smith wanted five more of the locos.
Which is a pathetically tiny drop in the bucket of N&W's contemporary motive-power pool, particularly as even a TE-1 with nondefective generators was a poor replacement even for a single A, and in my opinion for a properly-boosted Y6, And yes, it was a bit more economical on coal and water, but the ash problem was likely insoluble (and highly irritating to engine crews, according to Mr. Newton).
Stuart Saunders wanted none. Not because of any "65 mph", but because they "were not economical". Saunders won the battle.[/quote]
Yes, I wish he hadn't, but no, unless (1) there was sufficient sales volume for STEs to make line production economical and (2) there was a really quick way to make actual locomotive builders circa 1957 interested in building STEs there was really no more market for something long, finicky, and relay-logic controlled with most of the maintenance problems of steam power and a few added ones that only produced 4500hp. I don't find it too surprising that no one since has built STEs in production quantity, let alone gotten the equivalent of full diesel depreciation life out of them profitably -- and I speak as someone who has advocated the design and adoption of STEs, together with some other designs, since the 1970s.
Incidentally, Matt Austin has just posted over on RyPN an interesting Union Pacific DBTE v. speed curve which includes data for a "BLH steam turbine" of 4500 hp generator rating, identified in the fine print as the TE-1, compared to 4-8-8-4, 4-6-6-4, and both 3 and 4 GP9s in MU.
http://www.rypn.org/forums/download/file.php?id=14908
They don't bother to plot it past 60mph, unlike all the other locomotives in comparison, for what that's worth.
OvermodAlas! everything I say about the TE-1 is either from Louis Newton or source documents particularly at NWHS. The part about 65mph being a Baldwin fib is clearly stated in Tale of a Turbine, although since I don't have my copy handy I can't quote chapter and verse. In fact if I recall correctly he mentioned that N&W management was pissed at what was essentially a lie about achievement of practical 65mph speed under the conditions BLH had implied it would be achieved.
.
M636C As unlikely as it sounds, Westinghouse actually published an illustration of a streamlined turbine... Peter
As unlikely as it sounds, Westinghouse actually published an illustration of a streamlined turbine...
Nice found, Peter. I posted this pic on my pervious post as well.
btw.......
My fantasy Steam turbine locomotive PRR V2 #6600
Jones1945 (By Juniatha from Trains.com) A drawing I found on Facebook, showing a 6-8-6 direct drive stream turbine with T1’s shrouding. Looks like a fan art, no describion provided.(Edit: By Juniatha from Trains.com) If something like this was built in 40s, I guess a 4-8-6 wheel arrangement would be enough to do the trick. It would need a firebox and boiler as large as or even larger than S1, S2, a new gearbox system, advanced filter inside the pipe work to protect the turbine blade…… However, if the operation and maintenance cost cannot competitive with EMD’s product, it would be just another wasting of time project. Sigh...... I wonder if all the steam power connects to a Turbine-generator instead of a direct drive design would work better or not. The front end would need to redesign for more space, (IIRC there were 13ft of space inside the smoke box of S1). The drivers or even the wheels in both truck could attach to electric motor.
https://www.railarchive.net/wecbook/wec10.htm
Miningman The locomotive that killed the T1's. Brilliant....fish heads!
The locomotive that killed the T1's. Brilliant....fish heads!
lmao Miningman. I don’t hate all early diesels, but imo, only UP's M10000s and E2 to E6 were qualified to competitive with steam locomotive in terms of appearance. Diesel like E7/8/9 looked so dull and boring no matter how reliable they were I don't even call them a streamliner.
Overmod One thing to remember is that the timeline of certain improvements is highly interesting, and probably highly relevant, here. Remember that the internal correspondence as preserved goes from highly positive as late as 1946 to dismissive by ... about the time the improvement program for the T1 was cancelled, and this appears to be highly related to the staybolt issue (which is really far more terrifying when you think about it while reading the reports) BUT there appears to be no consideration of adapting the Bowes drive precisely when it was being carefully presented at some length to revive the V1 design for potential passenger use (i.e. what Loewy's design patent for it, in 1947, would involve)……
OvermodOh, I think by that time everything PRR had to learn from direct-drive turbines had been learned. If I remember correctly, what actually happened was that Westinghouse had essentially loaned PRR the turbine, and wanted it back……
Overmod in a perhaps more important sense nobody needs a passenger locomotive with six-wheel lead and trailing trucks necessary to support its weight. There is more to operating trains at high speed than being able to make the horsepower to accelerate and then pull trains in a straight line ...
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