Juniatha Hi , Thomas Not sure what you mean by statistics , I guess you ask for data & results . I may tell you some ‚echoes’ of the steam freight running days of 614 for these ‚tests‘ : When my father took me with him to visit the Vienna 150 years celebration of Austrian Rys in the summer of 1987 , we also went for a couple of train rides . On one of the trains headed by freshly restored 310.23 dad got to talking with one thinly silver-haired old engineer of whom I best remember that sharp , narrow nose vivid eyes and low whispering voice , chuckling when he or dad had made a sarcastic remark on something topical as dyed in the wool engineers sometimes do . I was not present during all of the conversation however I later learned this had been Prof A Giesl , the inventor of the known oblong shaped 'ejector' as he used to call his draughting device . Besides other things they had also spoken about ACE , the tests and a certain Argentinean steam loco engineer who claimed he had revolutionized steam loco efficiency . Dad later retold me what Giesl had commented on these tests : principally it summed up to the following : 1 – Loads : Ok , # 614 did manage to do the jobs asked , however , to quote dad quoting Giesl "only by reckless overcharging and coming razor-sharp on edge to stalling at places" . In spite of long years since passed I'm pretty confident his words very closely were as stated here , I recall what an alarming impression they made on me , instantly I visualized an American steam loco strained to the utmost , yet in peril to lose the battle - and then what ? I probably vastly over-dramatized the situation , they did have constant worries, though , including thermo-mechanical trouble with firebox staybolts . 2 – Traction and Efficiency : Prof Giesl clearly discarded anything useful could be gathered by these trips : „It’s not edifying in any way“ , only thing Giesl acknowledged : „ALCO had done a good job“ with designing and building this engine ( add =J= : actually it was a Lima engine ) ; on carrying through test runs in severe winter , annoyed : „It was a stupidity! Cannot think of anything useful they have demonstrated by that“ . Interestingly , the runs were done with firing fully left as it had always been – including cinder throwing , black smoke and all . No GPCS or part-gas-production combustion , in case you might think of it . 3 – Measuring : As told in David Wardale’s book ‚The Red Devil and other Tales of Steam‘ , from which I have occasionally quoted ( and clearly stated so when I did ) , many of the testing parameters could not consistently be collected , on some days of very icy low temperatures , measuring lines were iced up and not working , on other days some calibration was lacking and was mainly replaced by educated guessing . Personally , I think what could be measured must have told of a vintage engine strained to the very limit of its output as regards tractive effort at adhesion limit , including – of necessity – very uneconomic running at long cut offs and lots of wall effect losses in cylinders as the engine creped over the hard parts of the line . If not something really radical had been applied to the cylinders , and I have not heard or read of anything changed , nothing new should be expected from whatever data was collected . 4 – My comment : In an earlier thread I had commented on these test runs . In fact the runs were more or less a repetition of what most American RRs had regularly done in the late hour of steam traction – to load engines to the nines no regards to consumption or wear as anyways the locomotives were doomed to be phased out pretty soon . Same as back in late 40s all power at speed potential was wasted on slow speed dragging , the very range of traction that inevitably was and always must remain the major weakness of classic steam – i e direct drive – as against any power using full adhesion arrangement with electric traction motors on all axles of powered bogies . Mind , of a total of fourteen axles in # 614 but four were powered , or 29 % ! What can be learned from bidding such an engine against 100 % adhesion modern diesels specifically designed for awesome pulling power and realizing just that , more so when those very steam locomotives had already lost competition against diesels of much simpler technology and lesser power some forty years earlier ? Overload still was overload forty years later . Although sure enough there were some variations , expectably so , when reading through the ACE chapter in his book I noted Prof Giesl’s viewpoints were by and large confirmed by Wardale’s reporting and summation of this attempt . Juniatha edit : one add remark inserted
Hi , Thomas
Not sure what you mean by statistics , I guess you ask for data & results . I may tell you some ‚echoes’ of the steam freight running days of 614 for these ‚tests‘ :
When my father took me with him to visit the Vienna 150 years celebration of Austrian Rys in the summer of 1987 , we also went for a couple of train rides . On one of the trains headed by freshly restored 310.23 dad got to talking with one thinly silver-haired old engineer of whom I best remember that sharp , narrow nose vivid eyes and low whispering voice , chuckling when he or dad had made a sarcastic remark on something topical as dyed in the wool engineers sometimes do . I was not present during all of the conversation however I later learned this had been Prof A Giesl , the inventor of the known oblong shaped 'ejector' as he used to call his draughting device . Besides other things they had also spoken about ACE , the tests and a certain Argentinean steam loco engineer who claimed he had revolutionized steam loco efficiency . Dad later retold me what Giesl had commented on these tests : principally it summed up to the following :
1 – Loads :
Ok , # 614 did manage to do the jobs asked , however , to quote dad quoting Giesl "only by reckless overcharging and coming razor-sharp on edge to stalling at places" . In spite of long years since passed I'm pretty confident his words very closely were as stated here , I recall what an alarming impression they made on me , instantly I visualized an American steam loco strained to the utmost , yet in peril to lose the battle - and then what ? I probably vastly over-dramatized the situation , they did have constant worries, though , including thermo-mechanical trouble with firebox staybolts .
2 – Traction and Efficiency :
Prof Giesl clearly discarded anything useful could be gathered by these trips : „It’s not edifying in any way“ , only thing Giesl acknowledged : „ALCO had done a good job“ with designing and building this engine ( add =J= : actually it was a Lima engine ) ; on carrying through test runs in severe winter , annoyed : „It was a stupidity! Cannot think of anything useful they have demonstrated by that“ . Interestingly , the runs were done with firing fully left as it had always been – including cinder throwing , black smoke and all . No GPCS or part-gas-production combustion , in case you might think of it .
3 – Measuring :
As told in David Wardale’s book ‚The Red Devil and other Tales of Steam‘ , from which I have occasionally quoted ( and clearly stated so when I did ) , many of the testing parameters could not consistently be collected , on some days of very icy low temperatures , measuring lines were iced up and not working , on other days some calibration was lacking and was mainly replaced by educated guessing . Personally , I think what could be measured must have told of a vintage engine strained to the very limit of its output as regards tractive effort at adhesion limit , including – of necessity – very uneconomic running at long cut offs and lots of wall effect losses in cylinders as the engine creped over the hard parts of the line . If not something really radical had been applied to the cylinders , and I have not heard or read of anything changed , nothing new should be expected from whatever data was collected .
4 – My comment :
In an earlier thread I had commented on these test runs . In fact the runs were more or less a repetition of what most American RRs had regularly done in the late hour of steam traction – to load engines to the nines no regards to consumption or wear as anyways the locomotives were doomed to be phased out pretty soon . Same as back in late 40s all power at speed potential was wasted on slow speed dragging , the very range of traction that inevitably was and always must remain the major weakness of classic steam – i e direct drive – as against any power using full adhesion arrangement with electric traction motors on all axles of powered bogies . Mind , of a total of fourteen axles in # 614 but four were powered , or 29 % ! What can be learned from bidding such an engine against 100 % adhesion modern diesels specifically designed for awesome pulling power and realizing just that , more so when those very steam locomotives had already lost competition against diesels of much simpler technology and lesser power some forty years earlier ?
Overload still was overload forty years later . Although sure enough there were some variations , expectably so , when reading through the ACE chapter in his book I noted Prof Giesl’s viewpoints were by and large confirmed by Wardale’s reporting and summation of this attempt .
Juniatha
edit : one add remark inserted
Juniatha,
The account of the C&O 614 pulling coal in the ACE tests as told to you was pretty much spot on as I witnessed it myself.
Is the C&O 614 one amazing, rugged and powerful 4-8-4? Yes. Was watching the 614 pull 5000+ tons of coal at 50 to 60 mph impressive? Yes. Was using a Thoroughbred, 100+ mph, state of the art passenger steam locomotive to pull heavy tonnage through the mountains of West Virgina in -20 F weather a smart or even useful thing to do? Absolutely not.
I not bashing Ross for doing this. It is his locomotive, and he can use or abuse it any way he wants to.
The big problem with ACE, was they had no idea what was coming down the pike in a few years with diesel-electric technology. Everyone needs to understand, the locomotive the ACE3000 was designed to compete against was Chessie's "high tech" road unit at the time, the GP40-2. We used them on everything at that point. SDs were primarily used in pusher assignment, and while we were getting the new SD50 at the time, they were junk from the start.
Ross had no idea that a short time later, the super fuel efficient, microprocessor controlled, frequency drive, high horsepower AC unit would become CSX's standard road locomotive. Something that a traditional steam locomotive would never be able to compete against.
If you want to see how abused the 614 was even before the ACE tests, watch this link showing the 614 pulling 24 cars up the 17 Mile Grade (2.6%) unassisted. The blue smoke you see pouring off the front end of the 614 is Ross burning up the cylinders and valves with the 614's 810 degree F Superheated steam.
watch?v=UxdIyihG46U&context=C4e7398bADvjVQa1PpcFOxjCsNFUF9fYJmSUtiVvMfExJ0SUIybo=
Juniatha does raise some interesting points and does really appear to know what she's talking about.
I must confess that Thermodynamics was not my best subject in engineering college--perhaps that's one reason I became a civil engineer. We deal with things that generally do not move--which is generally much easier to comprehend--though still specialized.
In any case, even if the never-surrendering steam advocate's claims of 20% thermal efficiency could be actually achieved in real life at the railhead/drawbar, sadly the infrastructure to bring back steam power in the form of a high efficiency, even more complicated (than in the past) machine just is lacking, at least in the U.S. And even if we did, the maintenance forces would need retraining or replacement...So while the concepts may be intriguing, may show the best of what might have been, I don't think there's any danger of a "bring steam back" thread.
It's just too late.
John
Paul Milenkovic Juniatha: Overload still was overload forty years later . Although sure enough there were some variations , expectably so , when reading through the ACE chapter in his book I noted Prof Giesl’s viewpoints were by and large confirmed by Wardale’s reporting and summation of this attempt . The question is, what is one trying to accomplish with an ACE 3000 type locomotive? What was the Union Pacific trying to accomplish with the Big Blow gas turbine locomotives? They were often run in consists with Diesels, and I assume they were restricted to portions of the Union Pacific transcontinental main line, so gas turbines were not going to replace Diesels in the same way that Diesels swept away steam. Maybe the Union Pacific was trying to reduce the large number of units in first-generation Diesel consists so as to reduce maintenance costs? Maybe they had an eye on fuel costs because even though the gas turbines had much higher fuel consumption, their fuel was Bunker C, at the time an almost waste product of oil refining, or as the story goes, until the plastics industry bid up the price? So what is the ACE 3000 supposed to accomplish? Lower fuel cost, substituting coal for #2 Diesel fuel in mainline freight operations. It was never going to eliminate Diesels, their servicing facilities and the need for their liquid fuel. So instead of complicated boiler controls to allow MU operation, how about optimizing the steam locomotive into something like the last generation Big Blow -- a unitary 10,000 HP articulated locomotive with some number of trailing Diesels in the consist? Maybe a Super Challenger? The Diesels can act as booster engines supplying powered axles to get over ruling grades whereas the steam locomotive can lay down horsepower it is able to. Maybe such consists could be optimized with regard to axle count, starting tractive effort, and sustained HP for purposes of reducing the need for oil-based liquid fuel. Railroads have experience in excursion service with unitary steam locomotives with trailing MU'd Diesels, operated from the steam locomotive cab.
Juniatha: Overload still was overload forty years later . Although sure enough there were some variations , expectably so , when reading through the ACE chapter in his book I noted Prof Giesl’s viewpoints were by and large confirmed by Wardale’s reporting and summation of this attempt .
The question is, what is one trying to accomplish with an ACE 3000 type locomotive?
What was the Union Pacific trying to accomplish with the Big Blow gas turbine locomotives? They were often run in consists with Diesels, and I assume they were restricted to portions of the Union Pacific transcontinental main line, so gas turbines were not going to replace Diesels in the same way that Diesels swept away steam.
Maybe the Union Pacific was trying to reduce the large number of units in first-generation Diesel consists so as to reduce maintenance costs? Maybe they had an eye on fuel costs because even though the gas turbines had much higher fuel consumption, their fuel was Bunker C, at the time an almost waste product of oil refining, or as the story goes, until the plastics industry bid up the price?
So what is the ACE 3000 supposed to accomplish? Lower fuel cost, substituting coal for #2 Diesel fuel in mainline freight operations. It was never going to eliminate Diesels, their servicing facilities and the need for their liquid fuel.
So instead of complicated boiler controls to allow MU operation, how about optimizing the steam locomotive into something like the last generation Big Blow -- a unitary 10,000 HP articulated locomotive with some number of trailing Diesels in the consist? Maybe a Super Challenger? The Diesels can act as booster engines supplying powered axles to get over ruling grades whereas the steam locomotive can lay down horsepower it is able to. Maybe such consists could be optimized with regard to axle count, starting tractive effort, and sustained HP for purposes of reducing the need for oil-based liquid fuel.
Railroads have experience in excursion service with unitary steam locomotives with trailing MU'd Diesels, operated from the steam locomotive cab.
IIRC, you are dead on in regards to the economic advantages of Bunker C when UP acquired the GTEL fleet vs. later as demand from the plastics industry drove up the price of that grade of fuel. I've read in a number of sources that it was the fuel price issue that caused UP to go all diesel..
I was going to quip: "OH NO,NOT ANOTHER BRING BACK STEAM THREAD!!!!!!!!!!!!!!", but you do raise some interesting points......................................................
"I Often Dream of Trains"-From the Album of the Same Name by Robyn Hitchcock
Paul ,
Multi-traction capability with diesels was a major point with ACE3000 , sure , since with diesel traction being the starting point , clearly the state of the art was to slip in a different type of engine without too much irritation .
Imho , clearly too , this was a design challenge never fully met – it resulted in propositions loaded with hitherto untried components or components untried at least in this combination and context . The answer was modular design , accepting to have to replace failed components , aiming at making this as easy as possible .
I believe lower fuel costs than with diesels were aimed at , this would have provided a logic reason for being of a new generation steam locomotives – again I don't see how the #614 hard test runs did provide hope or basis for this .
Optimizing the steam locomotive into something like the BigBlow UP gas turbine engines : as for me , this would reverse design path : Once I got fascinated with increased thermic cycle efficiency promised in a high temperature high pressure condensing steam turbine loco with electric transmission and running of full adhesion bogies ( I had mentioned it in an earlier longer comment ) . I had chosen a BoBo-BoBo wheel arrangement and worked on it in my past time for about a year , while friends spend great times at discotheques asking where and when I had disappeared from view I was torturing my brain on voluntary night shifts over problem solving and finding some elegant solutions for arrangements or , ok half way elegant solutions, too – all for the proverbial 'golden pineapple' so to speak . In the end I threw out boiler , condenser and steam turbine ("hey , it wasn't my fault" she sang out) and replaced it by a gas turbine , beefed up electrical sychronous equipment to meet gas power and – whooosh – there it was : 8000 hp at turbine shaft at 160 t loco service mass .
So , don't ask me for a favourable comment on perspectives of steam turbine loco design : I call it a wonderfully complex and intriguing machine as such – yet not competitive .
UP's BigBlow - yes , I guess they wanted something more akin to BigBoy power at speed they had become used to , without having to pile up half a batch of diesels fresh from assembly line . If bunker oil provided a cost saving I cannot say , although it did do so as late as in the 1970s with oil-fired steam versus diesels on DB and this was the reason why on the Emsland line with heavy traffic from the North sea via Emden to Rheine and Muenster at the south end all freight including heavy ore trains and all passenger trains remained steam until the last six surviving 012 Pacifics fell to the reaper in May 1975 – from what I learned it was an end more of necessity with engines completely run down than a willful stopping steam by pressure of extending electric traction . As it was , oil-fired 042 Mikes and 043 Decapods labored on until in September 1977 the last hoarse cry of whistle from the last 44 class three cylinder Decapod , 043 196 , marked the very end of steam traction on DB .
Optimizing steam from Challenger design on and use diesels as booster power on hard sections - yes , sounds good to me – although , we have to accept this was a concept that could have worked well in an extended lease of life for steam through the 1960s , maybe into the 1970s in America . In the wake of environmental considerations in a world past peak oil having to be careful not to get at war over fuel reserves – which I feel would be absolutely fatal – the engine concept of our wishes does no longer fit modern demands with offering maybe 10 % of thermic efficiency in actual traffic , at best some 14 .. 16 % from heat content of fuel at tender to power output at wheel rim ( leave alone at drawbar with a 500 t machine !) with possible peak efficiency just reaching some 20 % as I have read in a paper on a 4-6-4 29 bar re-superheated four cylinder compound by one of the remaining never surrendering steam advocates .
Regards
Juniatha Overload still was overload forty years later . Although sure enough there were some variations , expectably so , when reading through the ACE chapter in his book I noted Prof Giesl’s viewpoints were by and large confirmed by Wardale’s reporting and summation of this attempt .
If GM "killed the electric car", what am I doing standing next to an EV-1, a half a block from the WSOR tracks?
It's quite interesting - especially if you read it in some relation to Giesl's book 'Die Dampflokomotive - international' . Each German language steam loco engineer has - or wished had - written a book by this 'fundamental title' 'The Steam Locomotive' .
Unfortunately , as I was told in Giesl's book a whole lot of tables and calculation examples of the original Giesl manuscript are missing , the editor threw them out on judging "they are not interesting to most readers and only make the book more expensive to print" - a most belated (miss-) judgment fragmenting this tech-historically important book .
Maybe I should write one The Steam Locomotive' too , perhaps with a subtitle 'an epilogue to the type of engine that started it all' …
Ah, David Wardale, "The Red Devil and other Tales of the Age of Steam." Would that a person who did not have that book be able to read it. I have my name and e-mail to the fine folks in the United Kingdom who promise to make another printing of it . . . some day.
Does anyone know the statistics from Ross rowlands experiment with the 614 back in 1985? I know they did a lot of testing and put sensors all over the locomotive trying to convince the powers that be that steam locomotives hauled coal trains better that diesel locomotives. I remember reading a article about it a long time ago and the only thing I remember was " one thing we have gathered from our tests is that the rails really do take a pounding from a steam locomotive".
I know Ross is a regular on one of these forums but I don't think it is the Trains forums unfortunately.
One thing I think being missed here:
There have been statements regarding which steam locomotives lasted how late in UP service...and at least implied attempts to equate that information to which engines were somehow deemed to be "better" by the UP management.
We all these years later cannot fully appreciate the complexities involved in why some of the 4-12-2's operated late, after the other classes of steam were well on their way out--except that they apparently did a really fine job of moving freight on the portions of railroad east of Cheyenne. There were issues with servicing and reduction of steam facilities, rising labor costs, the dates various engines or classes received major overhauls, etc. all of which played a role as to which engines survived late.
Kratville commented in his excellent 4-12-2 books that I think as late as 1952, Union Pacific's motive power department fully intended to keep the last group of "improved" 4-12-2's, the Challengers, and Big Boys in revenue service into the 1960's. However, the availability of diesels and phasing out of steam-related facilities, combined with recessions late in the 1950's all played a role in accelerating the final end of these marvelous machines.
Rehor, in his excellent work Nickel Plate Story, reports the costs of servicing a steam engine more than doubled from 1950 to 1957, mostly based upon the skyrocketing labor costs in America.
Sadly, several of the awesome Santa Fe 2-10-4's and 4-8-4's went to scrap in very fine condition, some having never run after final heavy overhauls, and some having accumulated as little as only 10,000 miles.
Well , thank you , timz , yet the question is : at which cross sections / valve travel and all ...
Point is : they had formidable 'Arnold Schwarzenegger' sized boilers - yet how free did their engine units 'breathe' ?
SFe's 3765-and-later 4-8-4s were supposed to be 60% maximum cutoff; the 5000 was 60% and the 5001-5011 classes were 67%.
Juniatha:
I wish I had them...the only person I would know who might would be Stan Kistner (sp) who is an expert on ATSF steam. As soon as I can find his e-mail address, I'll see if he has any information he would be willing to share.
Hi txhighballer
Do you have detail data / technical drawing of
setup of these engine's valve gear and piston valve events ?
I'd like to check them ...
You have to remember the ATSF 5011's and 2900 Clas were built with limited cutoff, and were much more powerful in actual paractice than their published ratings. On test, the 5011 Class put out over 100,000 lbs. tractive effort (vs. the published 93,000 lbs.) and the 2900's put out more than 77,000 lbs. tractive effort ( vs. the 66,000 lbs. published rating.) I have relatives who fired them and have talked to engineers who have run them, the opinion is that on the flats, diesels couldn't catch them.. In the mountains, however, the four unit FT diesels could and did out pull them.
Hi Steamhead: I'm going to have to dispute your allegation that the early diesels outperformed the last generation of steamers. The first cost of a steamer was considerably lower than a comparable diesel lash up and the diesels needed to be lashed up because they couldn't match the horsepower output of any of the big steamers. In fact it's only now that individual diesel units are being built that match steamers in horsepower rating. The steamers could at least equal the diesels in speed potential and were better able to handle the quick stops and accelerations involved in commuter service. Early diesels tended to overheat their traction motors doing this job. The steamers could also butt their way through heavy snow and wade through flooded areas more readily than an early diesel. On the other hand the diesel could start a heavy train more efficiently, squeezed more miles out of a gallon of fuel, needed less infrastructure and manpower to support them and maintenance costs were lower, especially when the units were new. In brief, the latest steamers were generally better out on the road than the early diesels but the diesels were more economical to operate.
Hello Jim! This is the neverending discussion of what could have been with steam without the diesels. Please read the whole story in D.Wardale's "RED DEVIL"! He was the one being engaged in most of those projects as ACE 6000 - and had resignated at the end. The development of steam locomotives had com to a zenit during the late 1930s. All modern equipment had been added then to locomotves like those of the N&W. Standard stokers, Worthington heaters, Timken running gear, mechanical lubrication and others. In addition, long travel precise Baker valve gears with slightly limited cutoff led to improved performance at very high rpms. No way, they didn't try every innovation making sense due to lower cost per tonmile! None of the improvements coming later like turbines, late poppet valves, nickel steel boilers or extreme high pressure boilers were successful. The diesels and electrics surpassed all modern steam before WW II, both in performance and overall cost, worldwide. Nearly all the "Last Of Steam" were of 2 cylinder classic locomotives of Stephenson's design due to cost of maintainence. No way back - just think of energy waste and polution. Lest enyoy what had been (and still is running life) instead!
wdh
As far as Santa Fe going diesel, let's remember that the SF ran through some very arid areas of the country. Water was always a problem, it had to be treated and piped long distances where thirsty steam engines could get at it. No water problems with diesels to speak of. Also, since the SF ran most if not all of the locomotives with oil fuel, well, if you're going to burn oil you may as well burn it in the most efficient manner possible. Again, back to diesels. As a matter of fact the oil fuel situation would have applied to any road that burned oil in the steamers.
As to poppet valve and Capriotti valve systems, I've read that they arrived here in the US just a little too late for American locomotive designers to master them. They might have done so but for the advent of the diesel. Had the steam era not ended in 1949, who know what might have happened?
Hi Juniatha: OOOps! I'll have to correct that last post. The ACE went through several proposed wheel arrangements. The 6000 version actually featured a 2-10-2 configuration with a divided drive. You probably are on top of this anyway. Sorry for my faulty recollection! JIM
Hi Juniatha: Well yes, that is the fascinating hypothetical question. What kind of progress might have been made in steam technology had development not been arrested circa 1949. Some of the American lines actually hoped that they would be able to stay with steam in order to show solidarity with the coal companies that they were closely allied with. This was particularly true of the eastern roads like the Pennsylvania and the Norfolk & Western and, ironically, the latest steamers could often outperform the diesels in every way except starting heavy trains. But there were other factors. Steam engines need a lot of unskilled and semi skilled laborers and labor was expensive. The heavy wartime traffic had worn out most of the older steamers and diesel building capacity was available to replace them while the steam erectors were busy knocking out thousands of locomotives for shipment to Europe. Diesels represented so many advantages that even conservative minded railroad executives couldn't hold the line against them for very long although some of them did try! A small new chapter was written a few decades ago when oil prices and supplies caused a passing crisis. A consortium of engineers attempted to rethink the coal fired steam engine and came up with the ACE 6000 project. After establishing a data base utilizing a heavy ex C&O 4-8-4 they produced a plan that called for an articulated 4-6-6-4 ( if I recall correctly ) with many interesting innovations but no new ideas where valve gear was concerned. Oil prices dropped again before a prototype could be built but this probably counts as the very last word in American steam engine technology.
Hi Jim
The Santa Fe mainline ranked high among the most arduous in America and even worldwide – no doubt . If there was a good technical case for dieselization then it was the combination of heavy ramps with long level stretches through dry territory , all of it aggravated by a long total mileage to cover per run .
No question they were correct about searching for the most reliable of engine configurations .
The Walschaert’s type of valve gear was well adapting for designs aiming at low internal steam flow resistance / high cylinder efficiency – some of the most efficient steam locomotives used this type of valve gear . No need to venture into poppet valve gear , less so if design incorporated gear boxes between frames ( let’s leave alone discussing these designs by themselves , it would only distract from point essential)
What was important , though , was not to compromise on attainable efficiency of steam distribution – that’s what I wanted to say . This applies to any type of valve gear – that’s why replacing an indifferent kind of Walschaert’s with some mediocre design of poppet valve gear gave little advantage or may have changed weak points for other weak points – mostly to some unwelcome surprise .
So , in any steam locomotive , whatever valve gear was chosen – it had to be excellent , nothing less . Or that’s my parol – difficult enough to find examples of it in historical engines . Instead , an indifferent attitude largely prevailed . I find this hard to understand in view of sometimes almost desperate efforts to maximize power output by enlarging to the utmost some other power related features , such as grate , heating surfaces , boiler volume , as concerns engine unit : cylinder volume , piston stroke and consequentially wheel diameter , adhesion mass and – inevitably – locomotive serviceable mass ( engine complete with tender ) .
If obviously there was every desire to maximize engine capacity for traffic handling , why then wasn’t quality of valve gear design given more engineering thought ?
Valve gear was the means of distributing live steam – or in other words : it was the very control of how all the amount of steam produced at high costs was to be used for conversion into the one thing that decided on engine value as a means of traffic handling : power output !
For example , what would you say about a guy who back in the Sixties would opt on customizing his T-Bird to be competitive with all the newer muscle cars springing up and to do so he would take the 352 Small Block engine out , modify the engine bay to hold a mild compression 462 cid Lincoln engine , then take the standard dual carburetor off the 352 and put it on the Big Block , adapt and connect the standard exhaust lines to the manifolds and look forward for a dashing performance . You know the answer .
Point is : you can only have so much performance as you allow an engine to live up to – and free breathing is the vital point .
For the Santa Fe , lower specific steam consumption would have directly translated into longer runs on a fill of water and fuel , more power to be had for free to maintain a faster pace up ramps and easier speed keeping on the level – allowing to vary between higher speeds or lower consumption as considered best . There are the same parts involved in an advanced Walschaert’s , only dimensions , proportions , bearing design . contouring of piston valves and possibly material specifications make all the difference – no extra complication , no drawback in reliability . Within engines in ‘Old Europe’ ( can’t keep from citing Rummy’s immortal line ) an example of what I mean were the Riddles types of British Railway standard engines as compared with elder two cylinder engines of the Big Four . Wait a minute , sure BR engines were no match to late American steam as concerns sturdiness and mileage between overhauls , sure . However as seen in relation to the engines they replaced the Riddles engines definitely presented a good step forward . Equivalent valve gear improvements could have been ‘translated’ into American design and would probably have been realized in some ways had steam design and construction continued into the Fifties as it did in Europe .
Hi Juniatha: Interesting remarks about the Santa Fe 5011's American railroads were totally indifferent to the idea of any type of valve gear other than the usual Walchaerts or Baker arrangement driving spool valves. Only the Pennsylvania experimented with Caprotti gear and Franklin rotary cam poppet valves, type A and B. They found, as you have indicated, that there were significant gains in power and efficiency but the gear itself just could not stand up to the rigors of American operating conditions. Maintenance costs were very high and when valve stems broke out on the road you had an expensive engine failure to deal with. Santa Fe used the traditional techlology on their big engines. The 5001 and 5011 classes were intended to cover the territory between Belin, New Mexico and Wellington, Kansas. This involved a sustained climb of 1.27% ruling grade through Abo Canyon and long stretches of flat tangent running so the engine had to be versitile. They carefully measured cylinder back pressure and found it to be less than 10 psi except when the engine was working really hard. They assumed that these engines would spend some of their time drifting downgrade so they equipped them with Wagner Drifting Valves to relieve back pressure. In photographs the Wagner cylinder can be seen on top of the valve cylinder. I believe Santa Fe was the only American railroad to use this system which was practical for them because they had a lot of sustained mainline grades in their territory.
Quote >> The 9000's represent rather old fashioned thinking with the engine merely adding a extra pair of drivers to a post drag freight design. <<
Well , it was a little bit more than just adding up that extra axle to the 4-10-2 predecessor , or else the type would not have been a success : curve inscribing had to be solved and was by introducing an ALCO lateral motion device to the sixth coupled axle , too ( beforehand it was only used on the first one ) and by using a firebox with Gaines wall – both have done the job , although in hindsight they were less than complete design solutions . Keeping that single axle Delta truck below the firebox can be viewed as a sign of traditional thinking , on the other hand I feel both ALCO and the Union Pacific were reluctant to add yet another axle to what seemed a rather long wheel arrangement already .
>> I can see how a 2-10-4 could be in contention but why not consider the Santa Fe's 50ll Class 2-10-4. <<
Well , I actually had this class in mind when I first wrote somewhat cryptical of “a big Texas Type” being the equivalent of a 4-6-6-4 in tractive effort . However as for drive wheel diameter as well as for year of construction the C&O T-1 seemed to offer a good comparison to the Fetters Challenger . There is little question the Jabelman Chally was an improvement over the first series , no doubt .
>> A very interesting comparison occurred when the Pennsylvania railroad leased several Santa Fe engines and ran them alongside their J-1's ( virtual copies of the C&O T-1 ) in coal drag service. I'm betting that neither the 9000's or the Challengers could outperform the 5011's as freight haulers. <<
Oh yes , that’s right and it seems most people would agree the AT&SF 5011 class had an advantage as concerns attainable speed on the level with a given heavy freight . Much of that however should be attributed to larger drive wheel diameter and greater boiler capacity – not to any superiority in valve gear . Actually , I have always wondered why Baldwin had built such massive engines for the Santa Fe and then provided them with valve gear design .. which .. kind of .. uh-m , well , wasn’t really up to the task , to put it mildly . This must have robbed the huge 2-10-4 of some 1600 ihp at least – at same fuel heat energy consumption , mind it – compared with a more adequate valve gear design as of that era and that is not to mention design of a piston valve Walschaerts or Baker valve gear which would really have reached into high efficiency steam distribution ! ( This wouldn’t have come easy to design with the enormous cylinder volumes and piston thrusts realized in large two cylinder Super Power types of steam locomotives and would have called for some re-thinking from scratch including changes in cylinder tribology itself and draughting , inevitably , to trim down back pressure .) Inadequacy of valve gear effectiveness in large Baldwin 4-8-4 and 2-10-4 in view of hourly volume of steam entering cylinders at nominal boiler output rate was highlighted by need to work with valves having positive exhaust clearance for to get steam out of cylinders without excessive back pressure and , notably , to avoid over-compression . Some railroads seem to have encountered back pressure and consequential over-compression large enough to cause big end trouble by knocking due to rapid changes of directions of bearing loads at engine traffic speeds during opposing quarters of a turn while main crank pin goes past 90° towards 180° / 0° = back / front dead center in the second halves of forwards and backwards piston stroke . Minding , in a double acting piston engine such as a steam locomotive’s , mean effective pressure not only varies over piston stroke but also changes direction it will be easy to see what bad effects to mechanical running the resultant forces from excessive back pressure and over-compression could have when they were allowed prematurely to exceed opposing mass inertia forces , temporarily while passing through critical crank pin positions . That is why high back pressure and it’s usual intake counterpart of degressive filling pressure not only were a waste of energy depraving the engine’s power output for a given steaming rate but had a backlash on drive mechanics about as destructive as pinging or detonation is to a gasoline engine . However , steam locomotives were built extremely enduring and more railroads / railways than not ignored the cause of the problem while happily repairing the effects of it at overhauls and re-repairing and re-re-repairing .. until dumping steam altogether to order diesels off stock where it could be left to the builders to iron out initial troubles .
Yet – let’s take big steam for what it was , and an impressive sight the black locomotives must have been as they were thundering up and down the mainlines , continuing a tradition of high pedigree until going on their final journey of no return to the eternal plains of steam railroading while in our minds we keep up memories of steely giants which proudly repelled to adapt to the times when they were a-changing …
Hi Juniatha: Thanks for the e-mail comeback concerning my "mystery" engines at Vienna! It's a sad but common story. More than one American steam loco restoration has foundered on the rocks of hard-headed individuals unable to resolve philosophical or practical differences while the engine rusts into junk or gets evicted from its storage place and ends up finally at the scrap dealer's yard. I hope that will not be the ultimate fate of these three engines which seem to be good candidates for restoration. I've tried to follow the arguments about the 9000's and the Challengers but they have gotten into some very rarified territory. Just thinking as a layman I'm sort of surprised that it's such an issue. The 9000's represent rather old fashioned thinking with the engine merely adding a extra pair of drivers to a post drag freight design. With only two wheels supporting the firebox it must have had somewhat limited steaming capacity. The Challengers, especially the latest examples, were much more modern in concept with an adequate firebox supported by a four wheel truck, a flexible articulated frame, a divided drive resulting in less dynamic augment ( hammerblow, we call it ) and dual service capability. Furthermore, I notice you and your threadmates keep comparing these engines with the C&O T-1. I can see how a 2-10-4 could be in contention but why not consider the Santa Fe's 50ll Class 2-10-4. This monster is reputed to be the largest and heaviest non-articulated engine ever built yet it had larger drivers than the T-1 and was capable of faster speeds. A very interesting comparison occurred when the Pennsylvania railroad leased several Santa Fe engines and ran them alongside their J-1's ( virtual copies of the C&O T-1 ) in coal drag service. I'm betting that neither the 9000's or the Challengers could outperform the 5011's as freight haulers.
Hi folks
To unravel a mystery and solve the riddle –
the locomotive types with the long main rods – likely the longest in the world – were :
1st DR 05 class three cylinder piston valves high speed special series 4-6-4 of 7’ 7” drivers (2300 mm new tire diameter) – one of which is preserved in the Nurnberg railway museum .
2nd ÖBB series 214 two cylinder poppet valves passenger 2-8-4 , with 79 built in licence by Malaxa works for Rumanian railways – an original Austrian 214 is preserved at the Vienna transport museum , an ex CFR version has been bought by the Austrian railway historical society .
Interestingly , both locomotive designs independently came to use same length of main rods of 4.25 m ( 13’ 11 5/16” ) although stroke differed at 660 mm ( 26” ) and 720 mm ( 28 11/32” )
The one three cylinder 2-8-4 built by Sigl works at Vienna in competition with the Floridsdorf two cylinder type had slightly shorter main rods as can be seen on photos since cross head position is set back in relation to center of first coupled axle . In this way naming the 114.01 was a near miss .
By the way : although comparison of European and American locomotives of rather different sizes and specifications must be viewed with some caution , 26” stroke DR standard two cylinder types disproved N&W theory of longer stroke reducing specific steam consumption , since all of the DR engine classes showed ssc – or more precisely specific heat consumptions – way below those found in long stroked N&W classes . Without intending to extend on what were the thermo-dynamic reasons for this , may I just mention cylinder volume in relation to hourly steam volume at nominal output rate was basically larger in the DR engines and this , besides other differences in design specifications in superheater , valve gear and draughting , helped to improve steam expansion and reduce back pressure .
On the other hand , with the notable exceptions of LNER A4 ‘Mallard’ and some of the BR standard class 9 Decapods , none of the European engines was ever run on rotational speeds as high as those realized with the N&W J class although smaller absolute cylinder volumes and lower piston thrusts should have favored it – however , delicate mechanical design often stood against high mass inertia forces involved with high rpm running , DR standard engines were handicapped by relatively heavy main rods of plain sorts of steel , white metal plain bearings of – uhm – rather ‘traditional’ design , principally an evolution of pre WW-I Prussian railways standards , and exceptionally low degree balancing of reciprocating portions of rod masses , causing hard longitudinal rocking or ‘galloping’ , although rotating portions of rod masses were fully balanced and there was full cross balancing , making nosing virtually absent in these engines , even in badly run down condition . Problems with plain main rod big ends and rough riding effects by low balancing of reciprocating masses were main reasons for turning development towards three cylinder engines in the later 1930s mainline standard types 44 class 1936 production type 2-10-0 , 45 2-10-2 , 01-10 and 03-10 streamlined Pacifics plus the 05 and 61 classes streamlined high speed engines . Still , with dual axle drives of much differing rod lengths inside / outside , DR three cylinder types suffered from principally the same unaccomplished design features as did the ALCO three cylinder types , additionally there was no counterbalancing on crank axle , instead it was allowed for by size and setting of counterweights in wheels of that axles – which did not help mass inertia effects on the crank itself , although this appears to have proven of little consequence with moderate rotational speeds of these engines .
While development of American steam left the three cylinder type to concentrate on pursuing purely outside-cylindered power for the benefit of ruling system of engine maintenance and servicing , the Germans principally repeated the same uncomplete mechanical concept in their 1957 class 10 ‘Super-Pacific’ that was to be the final steam loco design for DB , although the two engines were fully equipped with roller bearings on rods and axles and featured very low specific steam consumptions competitive with those reached in British Railways poppet valved three cylinder Pacific 71000 ‘Duke of Glouchester’. While in Britain , Gresley’s successors introduced some improvements on his concept of three cylinder engines with conjugated valve gear drive , with exception of said sole 71000 BR’s final design solution really was a retreat to plain two cylinder design that by default avoided all the technical challenges implicit with engine types featuring cylinders and drives between frames .
Or – design of the classic steam locomotive at the twilight of the era retreated to it’s very initial Stephensonian concept . I leave it to each of you to draw your own conclusions as to what that meant in view of competitiveness and future perspective offered by steam locomotive design at the time of emerging other engine concepts for railroad traction …
.. and so – how are we to sum up the thread’s comparison – the Challies to the Nines ?
To pull – or not to pull
that’s the question !
Shakesgear
Hi -
Well as concerns adhesion limit starting tractive effort , I can see an advantage worth the equivalent of one driving axle in a straight frame engine as compared to an articulated ( always at same adhesion mass per coupled axle ) - however a relation of five to eight would seem far fetched . I think when C&O was rating their T-1 2-10-4 as 'powerful' as the H-7 it's very much the product of ton-miles that they had in mind , i e the maximum tonnage on a given grade may have been somewhat lower with the T-1 , yet in the end they handled their loads a that much higher average speeds , their ton-miles production was much the same or even better .
M636C:"If the T-1 had been that powerful, UP could have used them instead of the 4000 class...."
I am thinking this is true for certain speeds. They had '68-'69 wheels. But not as a replacement.
I'm not sure what is meant by "an easter egg" except that they are sometimes hidden....
The obvious hidden locomotive is the second most powerful locomotive on the table, the UP Class 3570, which is of course the same C&O H-7 mentioned above.
Dear M636C,
Your intention have brought you on the right track in both cases. Some words about the 2-8-8-2 H7: these 30 engines were aquired from C&O 2nd hand in 1945. Together with 5 2-8-8-2 Y3 from N&W, they had become UP's final aquired, steamers. #844, the last new built engine, had been delievered '44
M636C And you pointed out as well, it was the second most powerful locomotive on the table, related on tonnage ratings (on home terrority, they moved trains of almost 10000tons. Maybe not 100% figure.)
This does raise the question that the 3570 is considerably more powerful than either the 9000 or 3800 or 3900 (as might be expected). However, it strains the bounds of credibility that the C&O T-1 could be more powerful than a 9000 or 3900....So a T-1 can't have been more powerful than an H-7, although it may have been able to do the same work as the H-7 was used for by the C&O."
The table just contains plain tonnage ratings. There are some general comments about handling trains (fast freight, tonnages with double-headers on step grades and maximum downhill capabilities) in addition. But no hint, of average speeds between those sections. The H7's higher starting TE than any other of UP's engines, except of the 4000-class, can not tell the whole story: Maybe not on all circumstances, like real starting TE from stop to crawling speed, on the other hand C&O T1 generated more HP.
This is why I like the table: it tells you everthing, but nothing all:
2-8-8-0-SA type was an older class than a challenger, but on steeper grades, tonnages remain same for both, as well as for 9000class.
For what is worth: from 1900 Built engines to Big Boy, Steamtech looks like a pretty linear development about HP. Big Boy is twice as big as an old 2-10-2-TTT, and could pull twice tonnage on steeper grades. Nothing great about that.
Come on, lets play with some trains here.
BigBoy4017 I encourage you and everybody interested to find the "easter egg" in the U.P. tonnage table on the first page of this thread...
I encourage you and everybody interested to find the "easter egg" in the U.P. tonnage table on the first page of this thread...
Earlier 4017 posted
"Consider, Bullmooses were X-8-8-X types, C&O recieved quite simlar results in a H7 (simple, 2-8-8-2) and 2-10-4 T1 comparison. Same pull, and better road-speed go to the rigid type engine, again." The obvious hidden locomotive is the second most powerful locomotive on the table, the UP Class 3570, which is of course the same C&O H-7 mentioned above. This does raise the question that the 3570 is considerably more powerful than either the 9000 or 3800 or 3900 (as might be expected). However, it strains the bounds of credibility that the C&O T-1 could be more powerful than a 9000 or 3900.... So a T-1 can't have been more powerful than an H-7, although it may have been able to do the same work as the H-7 was used for by the C&O. If the T-1 had been that powerful, UP could have used them instead of the 4000 class.... M636C
"Consider, Bullmooses were X-8-8-X types, C&O recieved quite simlar results in a H7 (simple, 2-8-8-2) and 2-10-4 T1 comparison. Same pull, and better road-speed go to the rigid type engine, again."
This does raise the question that the 3570 is considerably more powerful than either the 9000 or 3800 or 3900 (as might be expected). However, it strains the bounds of credibility that the C&O T-1 could be more powerful than a 9000 or 3900....
So a T-1 can't have been more powerful than an H-7, although it may have been able to do the same work as the H-7 was used for by the C&O.
If the T-1 had been that powerful, UP could have used them instead of the 4000 class....
M636C
I should have listen to this song first,
"Dry Bones - The Delta Rhythm Boys" ( http://www.youtube.com/watch?v=mVoPG9HtYF8 ), before answer, and tech. connecting the head-bone with the knee-bone. Of course, you knew meaning. - First attempts were a quick guess of mine. It can not be not the "Charlie" Chape-leon French 2-12-0 and ...ooorrr? - and German Württemberg locomotive Type K
4017
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