Flintlock76 ...If you don't have coal or oil you burn what you've got.
...If you don't have coal or oil you burn what you've got.
As those Spanish speakers would say, "Quando hay hambre, no hay pan duro."
When one is hungry, there's no hard bread.
Paul Milenkovic Cuba is not a powerful and wealthy country. I suggested that the need for Cuba to engage in self-reliance rather than just importing diesel locomotives and diesel fuel like everyone else could have been a catalyst for the reemergence of a steam locomotive others would want.
And it would have made a lot of sense for them. The beauty of a steam locomotive is as long as you've got something to burn in the firebox you've got power. In Cuba's case all that bagasse from the sugar cane fields. The Filipinos burned bagasse in their steamers too.
If you don't have coal or oil you burn what you've got.
I started this thread with the idea that bringing back steam locomotives to do useful work was a good thing. I brought up the Prometheus project in Cuba as having had possibilities. Instead of "going big", this project "went small", and a small high-tech steam locomotive may have a better chance of succeeding. For starters, smaller things are less costly to build than big things.
The word pariah means an "outcast" or a person who is "despised and avoided." If you are a pariah, that does not mean that you are a bad person. It means that there are people, who for whatever reason, don't want to associate with you.
OK, I "get" that the only country "shunning" Cuba and its people is the United States?
Blame it on the U.S., blame it on Communism, blame it on the fall of Communism, blame it on past neo-colonialism, blame it on the weather, Cuba is not a powerful and wealthy country. I suggested that the need for Cuba to engage in self-reliance rather than just importing diesel locomotives and diesel fuel like everyone else could have been a catalyst for the reemergence of a steam locomotive others would want.
This business of having every word parsed and every idea questioned is simply getting out of control.
If GM "killed the electric car", what am I doing standing next to an EV-1, a half a block from the WSOR tracks?
I have been asked to reconsider my posting, I may have taken a few things
Paul wrote too hard. So I deleted it.
Sara the one and only 05003
Paul MilenkovicWould a person "flame" me for suggesting that both South Africa in the era of the Red Devil along with Cuba at the time of the Prometheous project were pariah nation states in that both were subject to economic sanctions?
Pariah nations? Certainly South Africa at the time, but Cuba was a little different. Only the United States had an embargo on Cuba, Cuba could trade with any other nation they wanted to, and vice versa.
I've seen this on and off in the past, blaming the big bad US for Cuba's economic woes. Sorry, their economic problems weren't our fault, they were THEIR fault.
Communism doesn't work. Even the CCP figured that out.
What kind of political/economic system does China have now? In an odd way it makes me think of Fascist Italy, a capitalist economic system under the rigid control of a dictatorship.
Flintlock76 Well, God rest his noble soul! Maestro Porta didn't see "left," and he didn't see "right," he only saw steam and the best ways to keep it alive, no matter who used it. One has to admire him for that. A steam locomotive's like a big friendly dog, it's apolitical.
Well, God rest his noble soul!
Maestro Porta didn't see "left," and he didn't see "right," he only saw steam and the best ways to keep it alive, no matter who used it. One has to admire him for that.
A steam locomotive's like a big friendly dog, it's apolitical.
Well yes and no.
Would a person "flame" me for suggesting that both South Africa in the era of the Red Devil along with Cuba at the time of the Prometheous project were pariah nation states in that both were subject to economic sanctions?
That in a free-and-open-trade situation, diesels are what people use, but if your country isn't free to trade with other countries, for whatever reason, steam is considered?
As Overmod suggested, it appears that for steam to reemerge in one of these pariah countries, there has to be a confluence of this status along with the sanctions not driving the country in question so far backward that it cannot find people to fabricate a boiler?
In the Red Devil, Wardale chronicles experience in three cultures of countries with some level of pariah status. The U.S. could be considered in this category because the early 70's and early 80's "oil shocks" could be considered non-free markets in oil where other countries were sanctioning the U.S.?
In South Africa, Wardale, with some exceptions, found a "can do" spirit among the train crews and shop workers although the higher-ups were "passive aggressive" on retaining steam. In the U.S., the effort was largely mired in Vu-Graphs and meetings and never cut any metal -- HSR is encountering the same problems here in the 21st century. In China, they had emerged from the Maoist days just long enough to bring in Wardale but not long enough to get past the culture living under a Marxist-Leninist regime of "just do enough to get by and do no more to not call attention to oneself and get into serious trouble." Once China developed whatever kind of economic system you call it that they have these days, where there are no economic or political constraints on trading with other countries, they no longer feel the need for steam locomotives?
I got it. The last frontier for a steam revival is -- North Korea?
Erik_MagStrangely enough, stainless steel can actually perform better being 3D printed due to the rapid quenching.
With the advent of cheap fiber lasers (how quickly disks seem to have become obsolescent!) practical joining of 5" or thicker sections has become essentially routine, with surprisingly small HAZ in practice. Normalizing the structure still is wise, and takes time, but you can literally build the necessary CA 'furnace' in a back yard and fire it with domestic gas...
If you look at the original feasibility plan for 5550, the 'default' was always to be lost-foam castings and waterjet/laser (shipyard cut if necessary) hydroformed plate. That puts engineered material in place of structurally-indeterminate bulk mass in the engine bed, but keeps the advantages of castings where appropriate (and, perhaps importantly for the historians, allows a certain similarity to the control dimensions of the original).
In some alternate life I was told that GSC cast engine beds in multiple simultaneous pours, with slightly different alloy composition for different parts diffusing together seamlessly. This was attractive enough that I took it as design 'gospel' until a couple of people with real-world forging experience and historical knowledge of GSC and locomotive builders noted it was done with just two pours... hence the intricate gating, very large excess capacity in it, and the expressed expectation that multiple castings would be needed to ensure a fully 'usable' result. Personally... I think laser keyhole welding is a better answer today.
J,
I was being a bit facetious with the 3D printer comment.
As for the materials aspect, I've told my son that there should be a big future in working on materials for 3D printing with his search for grad school. Strangely enough, stainless steel can actually perform better being 3D printed due to the rapid quenching.
I'd like to hear about your work.
As for the T1 project's frame and boiler, here's a discussion over on RYPN from a couple years ago about that very subject, with a post from their general manager explaining why they did not choose a cast frame:
http://www.rypn.org/forums/viewtopic.php?f=1&t=43986&start=30
jasonjohnson We have already contacted 2 different foundries and sent them drawings of our frame to cast complete. One came back as a no bid and the other one wanted a minimum of 3 pours to get it right. The patterns and 3 pours would cost us $2.5 million. The company was more than capable, but felt it would take at least 2 pours to get all the gating right. From above "if mass producing today they would cast frames" the truth is this is a one off. As Kelly showed, the PRR fabricated cylinders many times and even converted a K4 to poppet valves with welded cylinders. We have copies of those drawings and our engineers as using them to convert frame to weldments and some smaller more manageable castings.This is the path we are headed down after boiler is mostly complete (minus tubes/flues)We will be releasing frame drawings once we have completed conversion and finite stress analyses. Look for more details on this at the PRRT&HS convention in May.
We have already contacted 2 different foundries and sent them drawings of our frame to cast complete. One came back as a no bid and the other one wanted a minimum of 3 pours to get it right. The patterns and 3 pours would cost us $2.5 million. The company was more than capable, but felt it would take at least 2 pours to get all the gating right. From above "if mass producing today they would cast frames" the truth is this is a one off. As Kelly showed, the PRR fabricated cylinders many times and even converted a K4 to poppet valves with welded cylinders. We have copies of those drawings and our engineers as using them to convert frame to weldments and some smaller more manageable castings.This is the path we are headed down after boiler is mostly complete (minus tubes/flues)We will be releasing frame drawings once we have completed conversion and finite stress analyses. Look for more details on this at the PRRT&HS convention in May.
Greetings from Alberta
-an Articulate Malcontent
Eric wrote: "On the other hand, maybe we can wait till someone makes a big enough 3D printer. Second best thing would be using 3D printed sand molds, though based on the one example of the 3D printed sand molds, a set for the T1 engine bed would be on the order of $10 million."
I had told the T1 5500 society years ago that there is a less costly method for building a one-off piece of frame: steel plates cutting, braces, guide stays, etc and welding it all into one piece. In tendency it will be lighter, yet it has to be normalized in the end and also it does not have fully the same quality of keeping to design measures as the old one-piece molding, yet it can be designed to fit the demand. But I got the impression it didn't find open ears, so to say. Neither my promoting fully welded construction for the boiler ...
Ok ...
=J=
3:24 ? what time is that?
Sara,
Ok - but I would need at least three members to request a posting to do it.
I think that's fair in view of the effort it takes to put it up.
And I choose which one.
Overmod The idea of the cast engine bed as a specialty is a tremendous expense, likely not possible today; its function, though, in reducing maintenance expenses should be preserved (and that is why modern practice calls for a combination of lost-foam castings and carefully-cut and stamped pressings via an appropriate combination of welding techniques).
The idea of the cast engine bed as a specialty is a tremendous expense, likely not possible today; its function, though, in reducing maintenance expenses should be preserved (and that is why modern practice calls for a combination of lost-foam castings and carefully-cut and stamped pressings via an appropriate combination of welding techniques).
The rudder bearing support for CVN's is on the order of a 400 ton casting, so casting an engine bed may not be completely out of the question... Pricing may be a bit on the high side.
On the other hand, maybe we can wait till someone makes a big enough 3D printer. Second best thing would be using 3D printed sand molds, though based on the one example of the 3D printed sand molds, a set for the T1 engine bed would be on the order of $10 million.
There is a somewhat lamentable tendency to overemphasize the importance of efficient Rankine-cycle thermodynamics. Interestingly, it's the powerplant engineers with their Byzantine penny-pinching heat balance arrangements that were among the first to affirm the importance of high running reliability over parsimonious fuel and water consumption -- and putting the complications and higher materials and system costs where it most mattered to the real bottom line: producing ton-miles without surprise.
Mercury topping cycles come to mind, along with the D&H 1400-1403 series of experimentals. On a more recent note, the Ft St Vrain HTGR was built with steam turbine driven helium circulators to give a fraction of a per cent better thermal efficiency. The problem was that shaft seals on the turbine end were leaking a bit of steam into the helium side and that steam was not a particularly nice thing to have in intimate contact with the very hot graphite moderator.
Flintlock76 Overmod My concern with the LVM is that Porta presumed that the Cuban system could produce both the necessary support and training and the necessary motivation and pride to support the complexities.
Overmod My concern with the LVM is that Porta presumed that the Cuban system could produce both the necessary support and training and the necessary motivation and pride to support the complexities.
Sara TGuys, say, what do you think?
So moved. Do I hear a second?
Oh, Juni!
Don't throw away an opportunity to put at least a little bit of light on your work!
Come on, you can do at least one. (I will talk to her!)
Guys, say, what do you think?
0S5A0R0A3
Maestro Porta may have been presuming a little too much. Steam-hunter Colin Garrett said the problem with Cuban steam maintanance was it ranged from outstanding to bombs looking for places to explode. He did see (and photographed) the remains of one of the latter, and this wasn't a crown sheet failure, this was the front course of the boiler disintegrating. The engineer was oiling all around at the time, they only found his legs.
CSSHEGEWISCHAfter reading these various posts, it appears to me that most of the proposed designs discussed entail an increasing degree of complexity that might improve operating efficiency but would require additional maintenance expense on what was already a maintenance-intensive machine.
Of course, optimization "today" involves a completely different set of criteria. Even looking at the 5AT effort vs. the LVM800 series will give you a constellation of different priorities (whether or not you agree that all the steps taken in either are 'right' from a North American perspective). A very wide range of careful alternatives were developed for the replica T1 5550, not all of which were judged 'worth the candle' to provide for the organization's announced purposes.
And it is for the organization with 'the gold to make the rules' to decide on what degree of complexity in the name of either thermodynamic or operating efficiencies are justifiable. My concern with the LVM is that Porta presumed that the Cuban system could produce both the necessary support and training and the necessary motivation and pride to support the complexities. In my opinion any practical chance of that closed with the collapse of the USSR, although few things would make me happier than to see Cuba take the necessary steps toward making it so.
Just an observation from a diesel enthusiast. After reading these various posts, it appears to me that most of the proposed designs discussed entail an increasing degree of complexity that might improve operating efficiency but would require additional maintenance expense on what was already a maintenance-intensive machine.
Overmod
Mind that I wrote
'or'
not 'and'
so decide which one ...
or, no: actually I think we better leave it as it is, for me it would only mean having to make up a text explaining details and I have to find and scan the drawing(s), so it would mean hours of work to put it up (and I don't have so much spare time today) and then it would only create trouble, me having to explain, defend, explain ... and so on, it would only mean hassle and bla-bla.
Naw, ok, let's leave it as it is - nobody hurt, me not either, everything's fine and we are all happy. Maybe some other time. Steam is gone anyways.
Never mind, have a nice day, today
Greetings
Paul MilenkovicThere is a complicated 7-bar linkage due to Peaucellier giving exact straight-line motion, but there is a simpler exact linkage due to Sarrus that is easy to build. The problem with the Sarrus linkage is that it has links sticking out of the plane, and it might pose clearance problems for use as a replacement for the crosshead guide.
The problem was that, in the version I saw, this presumed that the pin joints were adequate to 'take' any transverse component of thrust or reaction. I was not, and am not, convinced that this could be made to deflect or buckle sideways under not-uncommon conditions, certainly to the point you'd start to see Vauclain Compound-like distortion and blow at the piston-rod glands.
Something you might do with a Sarrus linkage is use a pantograph arrangement rather than simple hinging: this adds to the number of pin joints but reduces the necessary horizontal excursion. Whether this is in fact 'better' than good tribology on a suitably hard-faced multiple-bearing crosshead is... open to argument.
Juniathayou can't get around boiler water temperature increasing with increasing steam pressure, there is no way any circulator can help you: it will and has to reach its due temp before it can start boiling. What you probably point to is overheating of fireside surfaces due to bad water circulation and thus steam cushioning on the waterside - sure that would likely cause overheating - similar to that caused by scaling.
The 'enhanced circulation' as with Lamont boilers is to increase the water flow across the affected regions, to mechanically displace the extended boiling before Eisenhoffer/Leidenfrost effect can develop beyond the ability of saturation pressure to overcome it. The temperature of gas at the waterside does not change dramatically, but the nucleation to steam (or potential for departure from nucleate boiling in regions of highest, possibly transient heat flux) does, and of course the plate heating in those regions would increase (against what is now a reasonably-good insulating steam film, as in superheaters).
In a Lamont waterwall, the feedwater circulation is continuous at about 6x times peak steam demand, and 100% of the fireside waterwall is continuously swept at that speed, with the full steam generation carried mechanically through the space and no separation performed vertically into a 'steam space' until centrifugal separation. For Cunningham circulation (which takes downcoming water from the convection section and pipes it under jet-pump pressure to a manifold and nozzles spaced near the bottom of the water legs in a staybolted box) there is no 'special accommodation' for the accelerated circulation of 'pachinko' nucleate bubbles up the water legs once they get to the 'top' across the relatively unconstrained space above the crown. While in tests this notably affected the boiler's ability to take up heat from the combustion plume, it still leaves firing constrained by concerns over the crownsheet and its circulation. So it is practically difficult to enhance firing (or combustion heat transfer) to the walls without increasing exposure of at least some of the crown sheet to higher heat as well. but with lower defined circulation.
I agree with you that using suitably-hardened surfaces in a multiple-bearing crosshead combined with modern tribology is a 'right' solution compared to theoretically-low-friction pin-jointed anything. It is interesting to contemplate things that would shield that area from dust and moisture.
The method I devised to protect piston rods (and the rear gland) from contamination was to use a variant of a long-travel off-road shock boot between the rear of the cylinder block and the crosshead behind the piston-rod key. This can be vented to handle any blow, and easily removed and replaced for inspection; any severe shock would be accommodated by the elastomer and any internal contact with the rod surface insufficient to damage or distort it.
Easiest way to reach Andreas is probably via LinkedIn, if you 'do' that. PM me for the e-mail address I have.
Paul MilenkovicI guess I am being "tag-teamed" with criticism of Porta's ideas as being outlandish.
LDP was a friend, admittedly early in my life and late in his, and I do cherish his memory and respect the things he knew and loved about steam power. On the other hand, sometimes he seemed to assume certain things that differed from either my understanding or my opinion, and it is about these that I'm commenting. I don't mean to imply "I'm right and he was wrong" instead of considering the underlying issues for what they are.
The man did apprentice under Chapelon? He uprated and upgraded the 2-foot gauge Japanese-built 2-10-2's for heavy coal haulage in Patagonia, Argentina? He rebuilt a metre-gauge locomotive into his compound-expansion "Argentina"? He applied steam-powered rams for underfeed stoking, a version of the Gas Producer Combustion System (GPSC) and one of his improved exhausts to the Hunslet Austerity-class tank switch engine in England?{/quote]All that is so, and you should not leave out the Lempor as an ongoing example of what he was trying to achieve. None of that implies either that everything he innovated was supportable, or that everything he tried was necessarily a success. So by bringing up the Cuban Prometheus project, I am defending Porta as being all-knowing and all-wise in what further steam locomotive development could have accomplished?There are those who so believe. I deeply wish that someone would put his proposals for 'improving' the Tornado replica in detail, because they're fascinating. To this day Ross Rowland considers him to have been one of the most, if not foremost authorities on steam; he says he dismissed Mr. Wardale from the ACE program because there could only be one authority on development and Mr. Porta was it. To take the points raised, I am skeptical of Porta's claim of going to 1000 PSI boiler pressure with a staybolt firebox, or of even going to that steam pressure with a watertube boiler. The American Society of Mechanical Engineer (ASME) got its start in developing codes for boiler safety... And now do again; with the assistance of the National Board ESC they now provide a code for Locomotive Boilers again, a topic to which I'll return in a moment; the working factor of safety is now 5 in FRA part 230 (and yes, this has complicated the return of 1361 to steam even at 205psi...) ...and they recently published an account of an accident where contemporaneous with the Gulf War, the engine-room crew of the helicopter assault ship Iwo Jima perished from a steam release from a burst fitting in a 600-PSI steam circuit. The fatal accident was attributed to a contractor during a port call for repairs "in that part of the world" cutting corners in replacing the fitting with a substandard part or with the wrong bolts.My concern with high pressure is only peripherally concerned with substandard repair, although I did mention it explicitly and somewhat sardonically in my initial reply (as there are documented catastrophic sheet failures due to (nearly-incredible!) field welding and seal-welding practice even at typical 'mill engine' pressure, probably at most well under 200psi. I'll return to that, too, in a moment. Someone can tell me the pressure level that poses the danger that an invisible high-pressure steam leak can cut a crew member in half.I have only seen this in conjunction with submarine pressure-hull accidents, and a fictional account of one such led to my introduction to waterjet cutting tools (which were as I recall at the time an Italian specialty). In my opinion the likelihood of such a pinhole-nozzle leak on a locomotive that does not rapidly progress to a much larger "orifice" is relatively small, and unlikely to occur on a welded backhead or any other location where people might be 'adjacent to', that has been properly NDT-tested. Frankly I don't foresee the day that men, even in good modern nanoinsulated or armored suits, go into hot fireboxes as NYC had them do to take care of leaks at some high percentage of working pressure. That's the only other place I see a problem with mechanical damage. In any case, that isn't one of the real reasons not to use high pressure on a locomotive. You are welcome to sit in on one of the Code Week meetings that feature the Locomotive Boilers I sections (they are not conducted every Code Week, but you can have the agendas e-mailed to you) and discuss th The accident with the Fury locomotive using the high-pressure split-circuit Schmidt system in England along with the Iwo Jima accident suggests that pressures not much above 300 PSI are an accident waiting to happen in a mobile boiler subject to the railroad shock and vibration environment.The Fury failure is less of a motion cautionary tale as in having high-pressure elements exposed directly to a firebox volume which can communicate with the cab through either an open firedoor or secondary-air orifices. What killed the Superheater Company's man was superheated flame, not superheated steam. I believe there was a very similar accident to a French Mountain a few years ago that Juniatha discussed; there are pictures of the failed elements both there and in the case of Fury that are very enlightening concerning the force involved, but they notably did not progress to catastrophic release. I am also thinking of the scary but non-fatal incident of a burst circulator tube in "A Niagara Falls" in Steam Glory 3 as reason to stay away from pressures much beyond 300 PSI. I believe Porta that he studied the German TUV codes and that a staybolt boiler could be designed for, what did the Cuban locomotive call for, 368 PSI, but maybe the project could have backed off from that increase in boiler pressure?Perhaps, but the compound expansion benefits from higher pressure, and a 25atm boiler is not out of the practical range... thermodynamically. Much more of a question is how you maintain that pressure in the field, even with "too-cheap-to-meter" biomasa as the fuel. One of Porta's stated reasons for higher pressure is reducing the water rate, which is a significant issue on a locomotive operating away from sources of clean water (at least, clean enough to be made serviceable in a 25atm boiler) with a minimum either of chemicals or knowhow and discipline to dose them. Moving down the list, there is the 3-cylinder compound expansion and putting a pair of LP cylinders outboard? Isn't that the arrangement on the 242-A1?Yes, and on the Baldwin 60000 and other practical Smith compounds as well. This arrangement was one of the more 'proven' arrangements for compounds, with the center cylinder HP and the two outside LP totalling to near the desired expansion ratio.
So by bringing up the Cuban Prometheus project, I am defending Porta as being all-knowing and all-wise in what further steam locomotive development could have accomplished?
To take the points raised, I am skeptical of Porta's claim of going to 1000 PSI boiler pressure with a staybolt firebox, or of even going to that steam pressure with a watertube boiler. The American Society of Mechanical Engineer (ASME) got its start in developing codes for boiler safety...
And now do again; with the assistance of the National Board ESC they now provide a code for Locomotive Boilers again, a topic to which I'll return in a moment; the working factor of safety is now 5 in FRA part 230 (and yes, this has complicated the return of 1361 to steam even at 205psi...)
...and they recently published an account of an accident where contemporaneous with the Gulf War, the engine-room crew of the helicopter assault ship Iwo Jima perished from a steam release from a burst fitting in a 600-PSI steam circuit. The fatal accident was attributed to a contractor during a port call for repairs "in that part of the world" cutting corners in replacing the fitting with a substandard part or with the wrong bolts.
Someone can tell me the pressure level that poses the danger that an invisible high-pressure steam leak can cut a crew member in half.
Frankly I don't foresee the day that men, even in good modern nanoinsulated or armored suits, go into hot fireboxes as NYC had them do to take care of leaks at some high percentage of working pressure. That's the only other place I see a problem with mechanical damage.
In any case, that isn't one of the real reasons not to use high pressure on a locomotive. You are welcome to sit in on one of the Code Week meetings that feature the Locomotive Boilers I sections (they are not conducted every Code Week, but you can have the agendas e-mailed to you) and discuss th
The accident with the Fury locomotive using the high-pressure split-circuit Schmidt system in England along with the Iwo Jima accident suggests that pressures not much above 300 PSI are an accident waiting to happen in a mobile boiler subject to the railroad shock and vibration environment.
I am also thinking of the scary but non-fatal incident of a burst circulator tube in "A Niagara Falls" in Steam Glory 3 as reason to stay away from pressures much beyond 300 PSI.
I believe Porta that he studied the German TUV codes and that a staybolt boiler could be designed for, what did the Cuban locomotive call for, 368 PSI, but maybe the project could have backed off from that increase in boiler pressure?
One of Porta's stated reasons for higher pressure is reducing the water rate, which is a significant issue on a locomotive operating away from sources of clean water (at least, clean enough to be made serviceable in a 25atm boiler) with a minimum either of chemicals or knowhow and discipline to dose them.
Moving down the list, there is the 3-cylinder compound expansion and putting a pair of LP cylinders outboard? Isn't that the arrangement on the 242-A1?
As to the problems of overexpansion and cylinder compression and all of that, the idea of compound expansion is that if you expand to, say, 40% in both HP and LP, that level of expansion combined with torque smoothing from the 3-cylinder arrangement could, in principle, allow close to max tractive effort. 40% is no big deal as a cutoff with conventional valve gear, but in compound mode, that could get you to an effective 16% expansion giving high efficiency. Reducing the cutoff in both HP and LP to 25% would have you overexpanded?
Wardale said he was impressed on how one of his locomotive drivers took to full-throttle working, that not only did they guy "steam the locomotive" flat-out, he also "drifted flat out." Actually, alternating between full-throttle and "drifting" is a tactic for "hypermiling" in a gas-engine automobile, which is an automotive sport among the ecologically inclined car enthusiast, and this works especially well with hybrid or other cars that switch off the injectors during coasting.
Hypermiling acceleration, likewise, is done keeping the engine close to the effective peak of the torque curve, but this implies a transmission that can do the appropriate speed matching not to 'waste' any of that power especially at low road speed. Simple rods do this relatively poorly.
It might be more reasonable to alternate between full (or a large fraction of tractive effort) when steaming and then drifting where the greater mass of a locomotive and train cars stores kinetic energy with less change in speed.
[quote ...And yes, Wardale saying "go with pulverized-coal firing" is probably non-starter, probably from "slagging" of the front tube sheet even if you could solve the problem of a coal-powder explosion by grinding the powder at the point of firebox injections?[/quote]Slagging of the front tubesheet? By then your fly ash is not only solid but probably starting to be triturated...
On bagasse firing, Porta was said to have been working on that one, even to the point of stoking small black-power firecrackers on the firebed to mitigate the "caking" tendency of that fuel?
Seriously, if some enthusiast group with environmental leanings (cough, the Coalition for Sustainable rail wanting to break Mallard's speed record with a Wardale-ized AT&SF 4-6-4) were to concentrate on a Modern Steam project, perhaps a smaller-than-US-mainline passenger or freight locomotive such as the Prometheus locomotive might be a better focus?
The problem is that steam still requires regular attention and maintenance, and she behaves poorly when she doesn't get it, usually in many ways. That is my fundamental objection to building a highly complicated machine in relatively small numbers, requiring substantial training and discipline to 'care and feed'. We have already reached the stage where either a modern 'fireless' locomotive or a good battery locomotive could be used in conjunction with a modern bagasse-fired steam plant, with the standby efficiency and fire risk largely handled, and with no sensitive fired-pressure-vessel risks. Since such a plant is required to do anything with the sugar cane, much of the additional capital involved for the large plant and infrastructure is going to be paid for
>>That was my farewell to the 52-80 in Berlin in 1993 - a type of engine that never gave up and was thankful for but a handful of taking care!<<
I feel with you. You had told me about it. I know it was hard, but still I keep telling you: don't be sad it has ended, be happy you have experienced it!
The 42: Yes, I see, (s)he is much more rare than the 52, but doesn't look as well balanced with the thick boiler, (s)he looks shorter, too (is not really).
Hha! "bad brother of the 52"
That was before we got to know each other - I could have told you: you had a 30 - 40 % chance of succeeding, but looking at the severs consequences if you didn't it was fully right to abandon the project; you would have had a person with some power at the head quarters in Warszawa, but the people at Wolsztyn would have given you a hell of resistance against that loco leaving the depot. Irony: I feel the loco still exists and is externally made up. Could somebody from this forum know of it and tell?
the forum reads 9:44 - here it is 9:52: looks like it gives European time with my postings?
Paul Milenkovic Wardale said he was impressed on how one of his locomotive drivers took to full-throttle working, that not only did they guy "steam the locomotive" flat-out, he also "drifted flat out." Actually, alternating between full-throttle and "drifting" is a tactic for "hypermiling" in a gas-engine automobile, which is an automotive sport among the ecologically inclined car enthusiast, and this works especially well with hybrid or other cars that switch off the injectors during coasting. I have ridden on city buses that appear to be driven that way. It might be more reasonable to alternate between full (or a large fraction of tractive effort) when steaming and then drifting where the greater mass of a locomotive and train cars stores kinetic energy with less change in speed.
Wardale said he was impressed on how one of his locomotive drivers took to full-throttle working, that not only did they guy "steam the locomotive" flat-out, he also "drifted flat out." Actually, alternating between full-throttle and "drifting" is a tactic for "hypermiling" in a gas-engine automobile, which is an automotive sport among the ecologically inclined car enthusiast, and this works especially well with hybrid or other cars that switch off the injectors during coasting. I have ridden on city buses that appear to be driven that way. It might be more reasonable to alternate between full (or a large fraction of tractive effort) when steaming and then drifting where the greater mass of a locomotive and train cars stores kinetic energy with less change in speed.
Old streetcars were operated that way to spend minimal time in resistance notches. Gasolene autos would get more of a benefit from full throttle and coasting than a diesel auto due to pumping losses past the throttle. I recall seeing a plot of mpg vs speed for a MBZ 240 compared to a MBZ 240D. The mpg for the 240D peaked at 15 mph with a value maybe twice that of the 240, where both cars were presumably being driven at constant speed.
I was under the impression that steam locomotives were most efficient at substantially less than maximum output, possibly more due to less unburned fuel being sent up the stack and more time for the combustion products to reside in the combustion chamber.
Finally, for Professor Thinks-the-Baker-Gear-is-the-Coolest-Thing to have failed to have thought about what Porta's non-sliding crosshead could be been, such a thing has not happened.
The ACE 3000 specified "pendulum links" for the piston-valve valve gear, where a pendulum link gives a crude approximation to straight line. A much better approximation is the Watt's link (sometimes given as Watts link) used for guiding the rear axle up and down for the Police Interceptor version of the Ford Crown Victoria full-sized V-8 engined rear-drive car. It is also used by Talgo in its axle-guiding linkage. Steam engine inventor James Watt thought the approximation good enough to use with a beam-motion stationary steam engine, and people in the "live steam models" community have built them that way.
There is a complicated 7-bar linkage due to Peaucellier giving exact straight-line motion, but there is a simpler exact linkage due to Sarrus that is easy to build. The problem with the Sarrus linkage is that it has links sticking out of the plane, and it might pose clearance problems for use as a replacement for the crosshead guide.
Looking at the Wikipedia article Peaucellier–Lipkin linkage - Wikipedia, Lipkin is now credited? Professor Harvey Lipkin at Georgia tech is someone whose mechanism work I greatly admire, but someone stuck his name on this thing? Sorry, a different Lipkin contemporaneous with Peaucellier.
Wikipedia has good animation of the Sarrus Sarrus linkage - Wikipedia, and you can see where it could have clearance problems on a locomotive. I have built models of this Sarrus out of creased foam-core board. One could reduce the problem of its "elbow spread" by using a narrower angle between elbows than 90-deg, but then you reduce its stiffness.
I guess I am being "tag-teamed" with criticism of Porta's ideas as being outlandish.
The man did apprentice under Chapelon? He uprated and upgraded the 2-foot gauge Japanese-built 2-10-2's for heavy coal haulage in Patagonia, Argentina? He rebuilt a metre-gauge locomotive into his compound-expansion "Argentina"? He applied steam-powered rams for underfeed stoking, a version of the Gas Producer Combustion System (GPSC) and one of his improved exhausts to the Hunslet Austerity-class tank switch engine in England?
To take the points raised, I am skeptical of Porta's claim of going to 1000 PSI boiler pressure with a staybolt firebox, or of even going to that steam pressure with a watertube boiler. The American Society of Mechanical Engineer (ASME) got its start in developing codes for boiler safety, and they recently published an account of an accident where contemporaneous with the Gulf War, the engine-room crew of the helicopter assault ship Iwo Jima perished from a steam release from a burst fitting in a 600-PSI steam circuit. The fatal accident was attributed to a contractor during a port call for repairs "in that part of the world" cutting corners in replacing the fitting with a substandard part or with the wrong bolts.
Someone can tell me the pressure level that poses the danger that an invisible high-pressure steam leak can cut a crew member in half. The accident with the Fury locomotive using the high-pressure split-circuit Schmidt system in England along with the Iwo Jima accident suggests that pressures not much above 300 PSI are an accident waiting to happen in a mobile boiler subject to the railroad shock and vibration environment. I am also thinking of the scary but non-fatal incident of a burst circulator tube in "A Niagara Falls" in Steam Glory 3 as reason to stay away from pressures much beyond 300 PSI.
Moving down the list, there is the 3-cylinder compound expansion and putting a pair of LP cylinders outboard? Isn't that the arrangement on the 242-A1? Besides, Porta's idea was for a light-duty industrial/branchline locomotive with less cylinder volume?
I think what June is trying to say that if the compound cylinders were sized and the full-tractive-effort cutoff balanced for 40%, reducing the cutoff may require such a small level of cutoff in one of the cylinder banks that it would be unworkable with conventional valve gear without running into severe compression/rod knock?
And yes, even his acolyte Wardale was complaining about how hard it was to get the GPCS to work consistently, and Wardales luck in South Africa with a version of Porta Water Treatment consistently led to foaming and carryover that was ruining the superheater header from flash-boiling "bumping" knocks. And yes, Wardale saying "go with pulverized-coal firing" is probably non-starter, probably from "slagging" of the front tube sheet even if you could solve the problem of a coal-powder explosion by grinding the powder at the point of firebox injections?
Overmod,
you can't get around boiler water temperature increasing with increasing steam pressure, there is no way any circulator can help you: it will and has to reach its due temp before it can start boiling. What you probably point to is overheating of fireside surfaces due to bad water circulation and thus steam cushioning on the waterside - sure that would likely cause overheating - similar to that caused by scaling. To me, taking care of proper water circulation is a thing not mentioned because it is sine qua non to design."Are you familiar with Porta's design of a non-sliding pin-jointed crosshead?"No - I had once come up with my own lever system, mainly for slow power. However, an enclosed system where the slide bar goes around the crosshead instead of the old way with the crosshead surrounding the ruler and a good mechanical grease / solid lubrication or if we speak of up-to-date modern technology - a dry-running combination of materials (which then needs to be protected carefully against intrusion of dust and particles) with a slide bar and crosshead is still the best and potentially lightest solution. Such horrible amounts of wear and play as were tolerated in US steam are of course absolutely unacceptable and I wonder if that didn't break a piston rod now and then. At least it led to a quick demise of the rear stuffing box.Asymmetrically turned pin with different strokes coupling / main rods:I don't think it is worth dropping any more word about that nonsense and the weird forces it creates in the part, the only proper way to have a main pin is the regular symmetrical form, no doubt about it. Btw piston travel of the T1 was very nearly the same as standard with DR types of engines and they had the regular form of pins, i.e. same stroke for both coupling and main rods - there never was a problem with wheel centers cracking between pin and axle - and those wheels were comparatively very delicate in design. Many even 'survived' one or more water blows. For instance, I know that the Berlin group around their 52 8170 managed to fabricate a water blow when shunting at the yard around their shed at Schöneweide - the cylinder cover was pushed so that there was a huge steam escape from then on - yet the wheel was undisturbed. Full piston force at 228 psi b p is 45 tons (metric) - quite a thrust for an engine of less than 1/2 the axle-load of US mainline power, piston diameter is larger than that of NYC J-3a Hudsons!" it does make sense to decrease the amount of necessary overbalance in a high-speed engine"If you had been on the footplate of a German two-cylinder engine - which all did have that 'decreased overbalance' (but due to limiting the amount of hammer blow to 10% of static axle load) you would be much more cautious about this.I can only tell you the effect of the free mass forces set loose by this is disastrous to engine conditions. I have met so many engines that were worn down to the limit by this and were shaky in everything you could think of and then some! Some were nothing but an offense to the crew to drive at regular speed. True, to this usually came irregularities in valve gear working, in cylinder clearance and in axle bearings having developed play and - last not least - differences in wheel and rod spacings - one millimeter can cause hard riding if the bearings have not worn to tolerate it! Former work tolerances after an overhaul were 1/10 *) between two axles and 3/10 over all coupled axles - this was later given up to the end of steam traction which caused increasingly hard riding of virtually all locomotives - even the newly overhauled were little better. You can see that on the video I posted of the Swiss 01 202 of her trip from Stuttgart in my former posting.
On the other hand, I remember 52 8117 - then one of a few still on the roster of DR - at the head of a semi-fast regular train going north towards Berlin: she sure was rattling, you could see that from the car window, but she ran dead straight ahead - no nosing, no swaying, no nothing, just straight ahead, smoke wings vibrating, at somewhat above regular service speed limit, ~ 60 mph all the way, the train was light for her and there was no exhaust noise (the driver later said he used some below 30 % c/o and 6 bar (85 psi) at steam chest - close to the minimum (70 psi) you had to maintain to prevent clattering of the Trovimov piston-valves). There was just that hammering of the reciprocating mass at the bumpers of the first car (coupling was not tight enough, trainman who did the coupling had made it easy on himself). Yet when we arrived in Berlin-Zoo there was no hot bearing, not the slightest hint, the fire was fine on the grate and steam was plenty: safety valves soon cracked open at the stop. That was my farewell to the 52-80 in Berlin in 1993 - a type of engine that never gave up and was thankful for but a handful of taking care!Well, ok - excuse my digress ...
Juniatha
* one tenths / three tenths of a millimeter!
Oh, btw: "Have you contacted Andreas Schwander? This is a key interest of his, and I think he has connections to promote it."
No - how should I? Don't have the address, have no contact long since with the German steam preserve scene - and the opportunity is also gone long since: all remaining fireless 0-6-0s have been scrapped; same with wheel sets and auxilliaries including complete stoker machinery, there was a serious practical proposal to use the 1850 mm (73") wheel sets of a Pt47 and a 44 class crank axle to build a new 32 class Prairie three-cylinder engine with stoker firing on a 17 sqft wide grate of a new 290 psi boiler, combined with an ex 52 semi-cylindrical tender, one of the rare long form with 5900 mm (232") wheel base had been fixed at the ZNTK Gniezno. All gone - all scrapped! Well, I was just observing - only once I got more directly involved: when I saw at Wolsztyn one ex 42 in dull but at closer examination not too bad condition on the 'forlorn track'. I got to whirl up some PKP guys at headquarters about that engine, seriously attempting to bring her into the engine house and finally have her (I should say: him, because to me the 42 is 'the bad brother of the 52') overhauled. It were my parents who when they got wind of it made it clear to me I was about to chain a 150 tons chunk of steel to my feet and make myself depending on the more or less good will of a lot of people I don't even know. And even if I should succeed in making him servicable again - where would I go? to Schöneweide? Well, quite certainly not!! Vienna? the ÖBB / traffic museum, the ÖGEG, too, all had their own 42. The US even? Those costs of transport - prohibiting! And all that only to have endless trouble with US laws and norms and demands ... No - I slowly and sadly woke up ...
4:46h ?? It is 23:00h over here!
JuniathaPorta gave a most remarkable answer, in principle saying that "steel doesn't age" and there was "no need to keep designed loads below its full tensile strength" - and consequently he presented his own method of lengthening the stroke on a given wheels and pins material: turn down the diameter of the main rod pin asymmetrically towards the outer side. So, now he had a step between the pin section of the coupling rods that remained original and the turned down pin of the main rod with the already increased piston force and somewhat increased stroke.
In his defense, it does make sense to decrease the amount of necessary overbalance in a high-speed engine, and if you want (for some reason best known to a philosophical engineer like LDP) to do this with mains inside -- and there are good nominal reasons to have the mains inside the rods, as well as at shorter stroke than the coupling rods -- that design and perhaps no other would do it. Personally I think the rod force to all the coupled wheels, outboard of not only a necked section but an offset one, would be suicidal in the long run -- before we take up the issue of making the pin seat and axle seat far enough apart that the wheel center does not crack under loading too (note that the pin location in the 72" center of the T1 main was chosen to be a safe minimum for this not to happen; this too being explicitly discussed).
If Porta ever discussed DNB carefully (and the resulting much greater issues that might pose with hot-short characteristics), I have not seen it. A Cunningham circulator is supposed to deal with this somewhat in the water legs, but unless the transition to the crown or other structure (which is also partly determined by the desired combustion plume and gas flow inside the inner wrapper) is similarly improved you've likely set yourself up for problems. I also don't remember LDP proposing an effective way to keep watertubes wholly unencrusted without periodic turbining, something his published tube layouts certainly didn't make easy or inexpensive (and which historically has been one of the great stated failure points of even something as simple as watertube fireboxes). Meanwhile, while it was still the Porta-McMahon treatment, there were problems with the necessary antifoam additive at pressures (and saturation temperatures) even in the 200psi range, which I don't recall were satisfactorily addressed before the changed emphasis of the 5AT project. Now there are ways to get around that part of the problem (for example by greatly increasing the vertical steam separation) but I am still a bit nervous about using PT at very high pressures (e.g. where even small amounts of silica become a dangerous contaminant).
Are you familiar with Porta's design of a non-sliding pin-jointed crosshead? Professor Milenkovic, I think, would be fascinated by it ... in a number of senses.
JuniathaPerhaps I can post the side elevation of that Hudson type four cylinder compound design with 20 % overall efficiency - if there are enough requests to make me plunge into my files and uproot it.
Or, I may post my own design of an eight-wheel high drivered type four-cylinder de Glehn compound - the first three varying layouts of it I made in 1992 at the age of sixteen - that in her final version, as a Mountain (by w/a) type with a European standard w/a 4-4 tender, at least doubled the overall efficiency of some better late hour classic steam designs that have been.
Or - on quite the other end I could retrieve the 0-6-0 with a six wheel tender, a plan to rebuild one of Meiningen's fireless (without tender) built in the 1980s with a special design boiler of high water capacity to work industrial plants variably with / without firing for a whole day without replenishing supplies. I found it quite a cute design and a realistic proposal but the director of the Meiningen workshop didn't know how to promote it and, frankly wasn't half interested in venturing for something new - they rather did their same old standard procedures overhauls of existing preserved steam engines.
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