Here’s an interesting question. Had the diesel not come along, how much further could steam technology have progressed? What would have come after the 4-8-4? I know the Russians tried building a 4-14-4 and it was quite the epic fail. Realistically, a 4-10-4 would be the largest practical passenger locomotive US rails could handle.
I would opine that for conventional, rod-driven steam what was left was more efficient use of fuel and steam. Bringing steam forward to the present day, and given the drive for cleaner air, we probably would have seen a move to, say LP or LNG.
It’s possible that turbine technology might have progressed as ways were found to deal with the issues encountered with the likes of the Pennsy, C&O and UP steam turbines. Allowing electricity into the equation, steam turbine/electrics might have been developed effectively.
It’s even possible that MU operation might have been developed for the rod locomotives. It might still be necessary to have a “combustion specialist” on each locomotive, but one engineer might have been able to run a multiple-locomotive consist.
Which would tend to move away from the idea of really big locomotives (ie, X-10-X and larger, as well as articulateds) in favor of multiples of smaller locomotives (not that a 4-8-4 is necessarily small).
Interesting. It does necessarily assume that the Diesel was never successfully developed for locomotive use.
I think one factor in the diesels success was that steam couldn’t for all practical purposes progress any farther and without diesels I think that electrification would have been wide spread. After all a GG1 is a 4-3-3-4. The multiple unit diesel turned everything up side down even if initially each unit was under powered.
4-3-3-4 ?
We have recently has several long and very detailed discussion threads on this very subject over in the “Steam & Preservation” Forum on this site which you may find interesting.
This is the most recent one:
Oops, counting drive axles instead of wheels. The diesel influence obviously.
I think the limit to passenger steam locomotives was the boiler output. Electric locomotives could also be mu’ed and only require one crew and even then the only thing for the fireman to do was to wipe the sweat off the engineers brow.
What you are describing is a 4-6-6-4 Challenger, and yes, although they were built as fast freight engines they did see some passenger service (particularly on UP)…
This question has been posed and poised since the 1950’s. It has often been said that we know how fast a steam propulsion machine could go because we never were able to build one that could go faster or pull more tonnage than those we ended up with. Use of fuel other than coal, some said, was the answer. Others feared we did not have the metallurgical know how to produce a machine with the ability to take the heat , speed, and stress; others thought the contraption would fall apart at some point because we didn’t have the know how to keep it together. Is bigger better? Or maybe smaller? Could it produce enough steam with on board fuel and water to sustain itself for an economical and practical distance before refueling and watering? Even a water bottle on wheels fed by overhead electricity to produce steam would have to have all the above abilities and imperfections. Some say the use of and results of steam power are yet infinite. Others say it is too restrictive and expensive.
Once electrical propulsion and control of traction motors were made commercially viable the external rod steam engine was doomed. Wheel slip control is the name of moving tonnage effectively. External rod steam engines have the entire engine slipping until the engineer reduces throttle and regains traction.
With electric traction, no matter how the electricity is supplied, reducing power to slipping axles is controlled at the speed of electricy. While the original wheel slip controls diesels and electrics from the 30’s & 40’s were crude when viewed from today, they were several magnitudes better that external rod steam.
Had steam development progressed beyond the 40’s - it would have had to have been as a source of electricty for traction motors. Diesels with their relatively finite fuel control are vastly more economical to generate mobile electricty than steam boilers, as the diesel can be started, stopped and have it’s power output modulated as necessary for it’s load. Steam has to be being generated at all times as it takes a lot of energy to initially turn water into steam, thus steam can’t be started from cold and be productive in a matter of minutes.
Oh, dear. I see another 80+ post thread coming.
Having ridden in the 3985’s cab while she was under steam, I can tell you that, for the most part, locomotives built right around that time were quite a lot more efficient that was publicized.
I had a rather discreet discussion with the engineer and fireman, and can tell you the 3985 is quite capable of attaining and sustaining the speeds required for most HSR projects on the drawing boards today.
Same applies for the 844, that one was built for speed!
We had somewhat of the same discussion as to how far you could take a steam locomotive, and here are some of the observations from that discussion.
Modernizing certain aspect of say, the 3985 could remove a lot of weight, but beyond a given point, weight loss is not all that desired.
Some parts could be cast or machined from modern alloys, becoming stronger and smaller than the original parts.
Items such as boiler insulation, with today’s products, would vastly increase the efficient production of steam.
Condensing exhaust steam back to water would not be that difficult, although 100% recovery would not be really feasible, but the locomotives range would be increased dramatically, if a modern steam plant with a more efficient heating system were employed.
Boiler tubes redesigned to be more efficient, and could be replaced with more efficient ones made from alloys, the ability to design such tubes is available today, with the aid of computers.
As for MU capabilities, with today’s technology, replacing all the control surfaces, (throttle, brakes, reverser, blow down and such) with a standard EMD control stand would be
It’s about the given amount of BTUs extracted from an equal amount of fuel. So much fuel must be burned before you can extract work from a steam locomotive before any work can be extracted. I inspect boilers for insurance purposes and large marine-type Scotch boilers ( similar to a locomotive) are slowly going away. All that must be heated before you can use it and that’s just wasted fuel and fuel isn’t cheap. There’s also the infrastructure of coal burners that must be maintained.
I am intrigued by the idea of modern steam (remember Ross Rowlands) but not to get off-track, I am also intrigued by how far biplanes could have progressed had it not been for monoplanes. The last biplanes were pretty sophisticated as well as beautiful as were the last piston-powered aircraft, but technology reaches it’s limits.
As I said before, part of the premise of a discussion such as this is the assumption that there was no alternative - ie, the Diesel didn’t exist, or wasn’t suitable for railroad use.
Electric traction was certainly feasible, but one may question whether its adoption would have been universal.
As Ed points out, times have changed, and technology has advanced. Even a steam locomotive built today to the same form factor as we are accustomed would be a vastly different machine than what was on the rails at the end of the age of steam.
One must also consider what may have developed if the builders of steam had continued research and development - what directions might they have taken? They might have developed solution that we can only speculate on today.
Years (or decades) ago, Trains had a feature titled “Did We Scrap Steam Too Soon?” It raised the question of how the efficiency of steam locomotives could have progressed.
In 1996, the former SLM Winterthur (Swiss Locomotive Works) took a DR class 52.80 and revamped it, employing a number of technologies to increase not only the fuel efficiency, but also the environmental impact of steam locomotives. Though the results were stunning, the efficiency still did not match that of modern Diesel locos.
Add to that the high maintenance costs and you see why steam had to go.
I notice that nobody has mentioned the Withuhn proposal to minimize dynamic augment by driving one set of drivers with four cylinders set up so that the main rods on each side would be 180 degrees apart. Having approximately equal masses moving in opposite directions would have canceled the side thrust of a standard two cylinder locomotive. The down side would have been that there would have to be some between-the-frames connection (rods or gears) to keep everything timed right.
Then, too, if the boiler wasn’t sitting on top of the drivers it could be built to a more efficient design. Enter the Bayer-Garratt, which allowed a shorter, fatter boiler with a deeper firebox since the steam generator was slung between the engines rather than riding over them. It would also allow taller drivers if there was a need for them.
Some time ago a fellow forumite and I kicked around ideas and came up with a 4-(4+4)-6 + 6-(4+4)-4 Withuhn-Garratt, 500 psi triple expansion dynamically balanced monster. We estimated that it could easily generate 200,000 lb starting tractive effort (with boosters on the under-boiler trucks) and max out at over ten thousand horsepower at intermodal speed.
Chuck
The crux of the whole matter of the death knell of the Steam Locomotives IMHO is largely as Ulrich (Sir Madog) said:
:"…Add to that the high maintenance costs, and you see why steam had to go…"
It was the cost of the infrastructure needed to operate the steam locomotives. Thousands of specialist jobs, and their attendant pay. Not to mention costs of benefits to those workers; Then pile on the capital costs for that INFRASTRUCTURE: Bricks and Mortar, specialized tools and tooling, (and so on).
The diesel locomotive was a run-away answer to most all those issues. Diesels could be worked on in roundhouses, and many of the steam facilities might be used for the diesels, but efficiency might suffer as the facilities were not designed for those specific work related functions(?)
Lower costs for maintenance proceedures, less frequent cycles to maintain the diesels, fewer workers, lower costs those were drivers used by the railroiads to change from steam to diesel.[2c]
No, sometimes the fireman had to work with the steam generator so the passengers would not freeze (and, at least once, get the engineer to help him while the Pullman conductor ran the engine).
If steam had a future, it would almost have to have been with a water tube boiler, extemely high pressures, some sort of turbine / electric combination, and a fuel that burned much cleaner than coal like light fuel oil, LP or LNG. Condensers would have been nice in dry or alkali water areas, but not necessary. The net result is the bottom half of a diesel with a steam turbine power plant on top, nothing at all like a push rod steam engine. You steam fans wouldn’t like that any better.
As for the Garrett mentioned above, three modern diesels (one locomotive in all but name) could have easily outperformed it, and do just that every day on intermodal trains. After all, Garretts are really two locomotives sharing a common boiler.
There might have been some squeal left in the pig with modern materials and electronics for push rod locomotives, but by 1950 they had pretty much reached the limits of their technology within the size that would fit on a railroad track. The only development road left centered on reliability and maintenance reduction.
The real alternate to the diesel development track would probably have been widespread use of electrics.
The diesel vs. steam war wasn’t won on the road, it was won in the shops.
Even in the late '40s, the ‘advanced’ steam development was likely to be pointed at turbines. The V1 with ‘mechanical’ drive, using what was essentially a Q2 boiler, developed far more TE even at medium speed. Adding the Bowes drive fixed most if not all of the idling problem, and permitted better starting without ginormous instantaneous steam mass flow. The ‘killing’ issue was the water rate…
Conjugating a duplex drive is the ‘right’ answer for the high-speed slipping, but not Withuhn duplexing (which betrays a certain innocence of the requirements of roller bearings on drive axles, for instance). Deem’s approach for conjugating the Q2 should work just fine and eliminate any need for tinkering with fancy anti-slip valves in superheated steam. I would expect a reasonable follow-on (for reciprocating locomotives) to involve proportional-IP-injection compounding, followed by ‘asynchronous-compound’ LP expansion. Steam for air and water preheat tapped off ‘surprisingly early’ (as in modern stationary boiler practice) to get maximum benefits. Snyder and Cunningham as a matter of course.
Note that with increased thermal efficiency there is less reason for a full-monty Brobdingnagian firebox requiring excessive weight and a three-axle trailing truck. Two axles should be sufficient for one locomotive. Better balance for eight-coupled articulateds, compound or not, was an easy thing in 1945, and remains relatively easy today, if track speed need be no higher than for most current stack trains.
The ACE approach to modern power, in my opinion, suffered from a number of weird and brittle assumptions, not least of which was that a gas-reforming system could be run at locomotive scale, continuously, with high radiant production and proportionally high radiant uptake in firebox absorptive surface. It did not seem to me that Porta et al. had really looked carefully at the issues of
Google the ACE 3000 which Trains did an article on I think back in the 80s. During the time of its proposal coal was very cheap and diesel was climbing in price. No engine was ever made. If the cost of using hydrogen is not reduced significantly before we run out of oil in 100 to 300 years from now I think we will have no choice but to have steam powered locomotives. The bad part is that I will be gone by the time that happens.