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PRR Duplexes and Experimental Engines ( S1, S2, T1, Q1, V1 etc.)

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Posted by Overmod on Tuesday, August 21, 2018 1:17 PM

BigJim
Then 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.

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Posted by Miningman on Tuesday, August 21, 2018 2:16 PM

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

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Posted by Jones1945 on Tuesday, August 21, 2018 3:44 PM
I can feel you anger, Miningman....... 
 
 
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Posted by Overmod on Tuesday, August 21, 2018 5:33 PM

Miningman
No 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.

 

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Posted by Jones1945 on Tuesday, August 21, 2018 6:25 PM

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. 

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Posted by Jones1945 on Tuesday, August 21, 2018 9:13 PM
In case you missed it:
73 years ago, PRR made a scale model of S2 steam turbine locomotive, tried to find out what went wrong of the engine and what else they should had done to improve its design base on this model. 73 years later, a modeler from Switzerland made an O gauge S2 model, using a real scaled down turbine as power, please take a look: Yes


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Posted by Miningman on Tuesday, August 21, 2018 10:18 PM

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. 

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. 

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Posted by Jones1945 on Wednesday, August 22, 2018 8:27 AM

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. 

Exactly, I can only see this as an office politics or struggle thing between New PRR Management and Old PRR Management. Reader may note that: “Mar. 16, 1946  Howell T. Cover (1897-1960) named Chief of Motive Power replacing Harry W. Jones, deceased; Cover is an electrical engineer and thus more sympathetic to diesels; Cover orders all unmodified T1's sent to Western Region and modified ones to operate between Harrisburg and Pittsburgh. (MB, RyAge, Hirsimaki)” and Martin W. Clement the 11th President of the Pennsylvania Railroad left the office in 1948. At the same time, they probably needed to find an excuse to fool the stockholders, explain why the whole duplex development project was a "train wreck", which I never agree.
 
If this is really what happened, instant karma didn’t come late for them since even more money wasted on problematic early mainline diesel engine and about 300 new passenger cars in early 50s, under the leadership of the new management by Walter S. Franklin (1948–1954) and James M. Symes (1954–1959).
 
Imo, instead of reequipping their passenger car, they should have used those money to establish a new coaches company under PRR’s name, cooperate with N&W, to competitive with the Greyhound in even single corner around PRR’s territories. Just my two cents. Smile, Wink & Grin
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Posted by Overmod on Wednesday, August 22, 2018 12:05 PM

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. 

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Posted by Miningman on Wednesday, August 22, 2018 6:25 PM

Good grief, I'd rather discuss Seven of Nine than buses. Buses suck...and stink. 

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Posted by SD70Dude on Wednesday, August 22, 2018 6:49 PM

Miningman

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

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Posted by Miningman on Wednesday, August 22, 2018 7:13 PM

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. 

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Posted by Jones1945 on Thursday, August 23, 2018 1:21 AM
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……
 
They also abandoned any further development of S2 around that time, suggestion like this was ignored for obvious reason:
 
 
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)"
 
James M. Symes witnessed the whole development progress of the duplexes and direct-drive turbine steam locomotive as a VP since 1942, I don’t know if he tried to save the project or not, but the story of S2 and T1 ended in 1949 and 52 respectively.
 
Pennsy style front end Yeah Good looking Yeah Fast and powerful Yeah Loved by the public Yeah 
 
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.
 
Coincidentally I was reading about the Pickwick Nite Coaches from a issue of Electricity Railway Journal! The flexibility of Coaches had so much potential that it could offer a lot of things traditional railroad can’t offer. In hindsight, I believe if PRR established a branch of Coach Company like Greyhound, using coaches to assist or even replace some of the train service could increase the competitiveness of PRR, or at least let the business keep running. But Would ICC approve such plan? Imagine passenger could buy a ticket package from Pittsburgh to Chicago and then jump on a PRR bus to Milwaukee or took the train to St. Louis and then travel to Omaha or a bunch of smaller towns...... so many possibilities and business opportunities.
 
O wait, I forgot PRR was long gone…… and the Greyhound bus doesn't smell so good nowadays. Stick out tongue
 
 
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Posted by Jones1945 on Thursday, August 23, 2018 5:50 AM

Some patent drawings of the PRR V1 project (9000hp Direct-Drive Steam Turbine Locomotive) from 1946 (source: Google Patents): 

V1

 

Steam Turbine Electric Locomotive Vs Direct-Drive Steam Turbine Locomotive 

Steam Turbine Electric Locomotive like C&O M-1 and N&W TE1 were proved unsuccessful, but Direct-Drive Steam Turbine Locomotive in such structural design like the PRR V1 never had a chance to get built. Did we miss something great or would it be just another expensive failure?Hmm
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Posted by rcdrye on Thursday, August 23, 2018 8:52 AM

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.

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Posted by Backshop on Thursday, August 23, 2018 2:48 PM

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.

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Posted by M636C on Thursday, August 23, 2018 11:41 PM

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

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Posted by Jones1945 on Friday, August 24, 2018 5:25 AM
rcdrye
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.
 
Thank you for the response, rcdrye.
In hindsight, I think it was a consensus that the maintenance cost, operation cost and flexibility of diesel engine is superior to conventional reciprocating steam locomotive. Many railroads from all over the world tried so many different new technologies but turn out there is only two options, electric locomotive or diesel-electric, were proved economic and practical.
 
 
Speaking of Baldwin Centipedes, I agree that PRR or even Baldwin really addicted to massive engine design since 40s. Looking at the patent drawing of the Baldwin Centipedes, I really can’t understand how they could approve such “vanguard” design; There was no space for daily inspection or maintenance between the diesel engines and it wasn’t hard to imagine the noise, heat and vibration from the engine room which housing 8 diesel engines. Many things PRR and Baldwin have done just proved Murphy's Law is not wrong. (But they did look cool thoughStick out tongue)
 
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Posted by Jones1945 on Friday, August 24, 2018 6:01 AM

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.

It depends which year you are talking about. Passenger trains like the Trail Blazer and the General made tons of money for PRR prewar, not to mention the money earned because of the war traffic, even the ridership of Broadway Limited increased 210% after it dropped the extra fair. But of course PRR's freight business earned so much more.
 
By the way, when the problem of duplexes was sorted out, it was 1947, decline of PRR's passenger service was just started. At that moment, no one would have foreseen what would happen in the next decade, including heads of NYCRR, who purchased 720 new light weight passenger cars from various manufacturers for their “Great Steel Fleet”.  The rest is history.
 

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Posted by Jones1945 on Friday, August 24, 2018 6:25 AM
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......
 
Thank you for the detailed and informative respond, Peter.
As you may have noticed that there weren’t any successful example of steam or steam turbine engine using high pressure water tube boiler from all over the world, like LNER 10000 from UK, N&W Jawn Henry. It seems that the direct-drive steam turbine locomotive was a dead-end project……
 
I read some post from different forums that comment was made suggesting using of a steam booster engine on the trailing truck on S2, but I think PRR wanted a locomotive 100% power by steam turbine. If there is a gear allow the reverse turbine (1500hp) changed to forward turbine like an automobile, I wonder if it would solve the starting problem of S2 or made it even worse……   

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Posted by Overmod on Friday, August 24, 2018 10:11 AM

Jones1945
Looking 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...

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Posted by Overmod on Friday, August 24, 2018 10:38 AM

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...

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Posted by Jones1945 on Friday, August 24, 2018 12:40 PM
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. 
 
Thanks for catching that, Overmod, I should have said “the conceptional design of Centipedes” or other more actuate words to describe that engine in the drawing since I do remember the production Centipedes had “only” two 1500hp engines, even BLW was unable to install 8 but 4 engines on the demonstrator unit according to their original plan.
 
After reading your informative respond, now I understand why they had such an ambitious or some people may say a “greedy” design. A 3 units, 210ft+ long EMD E7 or E8 A+B+A set which could provide 6000hp was so much longer than the “original Centipedes design” (Essl modular locomotive) which was 91ft long providing 6000hp. That’s why Mr. Essl or Baldwin wanted to put so many engines inside one single engine unit to meet the 6000hp power output goal.
 
The Chassis of both conceptual and production Centipedes looked like GG1 with one more axle in both engine truck, I guess Baldwin wanted to build a mainline express diesel engine as powerful as GG1 with similar wheel arrangement. But turn out it didn’t work.
 
 
If thing went according the plan, a 91ft long single unit which can provide 6000hp power output was definitely very competitive to EMD's product and attractive to all railroads, but it was too bad that it didn’t went according to plan…… Bad luck for both comany. I heard that PRR's Centipedes were prefered engines for the Broadway Limtied, I think Its time for me to buy the Volume II of "Black Gold - Black Diamonds: The Pennsylvania Railroad & Dieselization" to see the ending of the story. (or any other books deserve a recommendation?) 
 
 
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Posted by Jones1945 on Saturday, August 25, 2018 5:59 AM

This is another drawing from google patent. According to the description, this is a device designed by Warren R Elsey from PRR  for Q1 to control the front and rear set of cylinders separately, in theory it could decrease fuel consumption and operating cost, it would be the best device to help relieve the problem of wheel slip at different speed, but for unknown reason, no such device was made and installed on the Q1 or other duplex engine like the production T1 and Q2.

The original design of Q1 was a 4-6-4-6 but by the time plans were finalized and approved it had evolved into a 4-6-4-4, poppet valve gear was deleted as well. (Source: Black Gold - Black Diamonds: The Pennsylvania Railroad & Dieselization Vol 1) There is some sources stated that the streamlined shrouding of Q1 was designed by Raymond Lowey.
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Posted by 3rd rail on Saturday, August 25, 2018 10:13 PM

Well, that was the problem. 

Miningman

Baloney! The development of the Diesel engine was true enough but it was 2 and half times costlier to purchase up front. Very expensive. Sizable fleets of Centipedes, Passenger Sharks Bp20's, FM opposed piston entries, Alco PA1's, RF-16 Sharks, even FA1's were a total waste of money and were junk in short order and that after sizeable maintenance headaches, costs, breakdowns and delays. 

Roundhouse backstops could rebuild, fix and repair steam locomotives quickly and efficiently. Pennsy and NYC would have done better to do exactly what you state the N&W did...hold out until bullitproof proven Diesel locomotives became available, even longer. 

They succumbed to pressure from a societal direction that was eager for a new world of massive consumerism and easy credit was waved in front of their faces especially by EMD. It was image, style over substance. It did nothing to save them at all, not a thing. 

 

The So-Called "Standard-Railroad" Failed to standardize on their Diesel purchases. They bought a little bit of everything. Baldwin, Lima, Alco, Fairbanks, EMD, GE, I'm probably missing a few others.... 

When you have a motive power fleet that diverse, how can you effectively shop the units for regular maintainance cycles without causing "Havoc" in the "Then-New" Diesel shops?  Most of the employees were used to working on steam. Now they have to learn about all these various new critters?  Disaster! Well, after about 10-15 years, PRR, along with the rest of them figured out that sticking with one manufacturer (usually EMD ), would simplify life. 

Of course you can't forget the Immense savings from eliminating all the coaling/watering facilities, the reduced shop force, etc, etc, etc.. 

Now, don't get the idea that I hate steam locomotives. I don't. I Love to see the restored ones in operation. But, I will say, if it weren't for the Diesel Locomotive, we would most likely NOT have any railroads left. The modern Semi-Truck  would have long ago, stolen ALL the traffic. 

Todd 

 

 

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Posted by Overmod on Sunday, August 26, 2018 9:47 PM

Note that Elsey's design, as written, is the wrong answer to not just a couple, but several questions nobody asked.  It's not particularly hard to understand why it was not applied to the Q1 to 'save' or assist it.

I suspect it would be difficult to find someone other than a French mecanicien (as on de Glehn- du Bousquet engines) who would voluntarily choose a system requiring manipulation of four separate controls, without conjugation or indicators of any kind, to synchronize or 'trim' power between two separate cylinder groups.  What is needed is a differential arrangement for each control, preferably one which can 'store' the offset needed for slip control, actuate it when needed, and then go back to normal sync or to "best" balance of power between units easily.

If you are familiar with the Eames locomotive, the wacky nature of the throttle arrangement in this patent, as drawn, will be appallingly clear.  At high mass flow the steam is NOT going to go neatly between the piping branches; it is also amusing to consider what the flow of combustion gas in the upper flues does to get around the considerable obstruction of the second throttle and interconnections.  Elsey appears not to know anything about Wagner throttles or the design of modern multiple front-end (poppet) throttles; there is no room for two of these on a T1 at any point in the available space for steam tracting, and even if there were, it would be better to use air actuators on both and control them from a single grapevine with a fast-acting differential control of some kind appended.  We have already discussed practical methods of detecting and indicating the pair of wheels slipping on a duplex -- a pair of simple wheelslip lights representing one of the better ways -- and it is not difficult to design a small motor-activated 'riding cutoff' arrangement (probably applied only to the 'slipperier' engine in practice) that would act in servo to extinguish the lights autonomically. 

I do agree with Porta that a better way to eliminate the slip on a duplex is to use four Wagner throttles (Porta couldn't spell very well and called them "Waggoner") which use fluidic amplification for very quick, very close control of fine throttle opening across the full range of actuation.  These go immediately upstream of the sets of ports and would be fed by branch manifolds similar to those used on Franklin poppet valves; they allow trim of one engine when the (single) main throttle is fully open and the engine is being driven on cutoff, and don't involve the weight and complexity of a complete separate power reverse arrangement.

The Wagner throttle arrangement is also a more correct way to implement, physically, the differential control as used on the Q2s, as it permits continuous control of the amount of steam admission rather than 'bang-bang' controlling the flow on and off with butterfly valves that require gland seals exposed to nearly full superheat.  To my knowledge there was no problem with the actual analog-computer setup used, which remains a highly interesting application of technology to steam power.

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Posted by Jones1945 on Monday, August 27, 2018 12:27 AM

Overmod

Note that Elsey's design, as written, is the wrong answer to not just a couple, but several questions nobody asked.  It's not particularly hard to understand why it was not applied to the Q1 to 'save' or assist it.

Thank you, Overmod. Obviously, I have no education background of Mechanical engineering, so when I share these patents, I am not, and never think that I am the best person here to judge it would work or not. I appreciate that you willing to spend your precious time sharing your professional knowledge and thoroughly reply or answer questions here and there. Unfortunately, it seems that many forum members here are not engineering expert like you, without engineering knowledge or experience, it is not easy to understand everything you wrote, not to mention asking meaningful questions. Just my two cents, this one is free though:


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Posted by Jones1945 on Monday, August 27, 2018 1:02 PM

 Estimating steam locomotive horsepower
Author: AdamPhillips (2013)


 

This is one of those things where you really have to ask the right question to the the answer you're looking for. There are many kinds of horsepower relating to locomotives. With a diesel, you're talking mechanical horsepower: 550 foot pounds per second....or Brake Horsepower...or Indicated Horsepower...or Shaft Horsepower. It doesn't work that way with a steam locomotive. 

For the 1876 Centennial Exposition in Philadelphia, some old guys got together and cobbled together this idea of Boiler Horsepower. Pretty much since 1876, boiler people tried to get away from Boiler Horsepower, at least as it was then defined. One Boiler Horsepower = the evaporation of 34.5 pounds of water in one hour from and at 212 degrees f. To really figure out how much Boiler Horsepower your boiler makes, you have to measure the steam output and have test equipment. 

What heating surfaces are there in a steam locomotive? It depends on what you've got. Total area of surface in contact with hot gas and below the normal water level as long as it's part of the circulation system of the boiler. Area of: firebox sheets (minus door hole, stoker, tube & flue holes, etc), arch tubes (OD), siphons, circulators, combustion chamber, tubes & flues (ID) from sheet to sheet. Superheater area is figured seperately.

You probably don't want to get into all those formulae and steam tables and stuff....and there's drawbar horsepower....aww, just use the easy way ALCo looked at it: 

Saturated Steam HP = 0.0212 X P X A 
Superheated HP = 0.0229 X P X A 

HP = Horsepower 
P = Boiler Pressure (in Pounds per Square Inch) 
A = Area of One Cylinder (in Square Inches) 

For most of the locomotives out there, you can easily find out what boiler pressure they run at and what the cylinder diameter is. Use this simple formula fore every two-cylinder steam locomotive you want to know about. You do the math on your cell phone and can make the comparison for your self. Leave all the egg head stuff to the egg heads who can then argue amongst themselves over minutiae.

 
  
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Posted by Jones1945 on Monday, August 27, 2018 1:16 PM

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Posted by Overmod on Wednesday, August 29, 2018 9:21 PM

http://digital.hagley.org/PRR_11454

Knew if I dug into some of the records, I'd find it.  This is the S1 backhead view.

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