I put this in a separate reply
Dr D Then there is the issue of N&W trying the Giesl (note sp.) type exhaust nozzle (note sp.) on their articulated locomotives.
To be honest, I don't know of any N&W articulateds that got Giesls (meaning the long-thin stack and elongated fan-shaped nozzle cluster). What I am familiar with in N&W practice is the 'waffle-iron' nozzle, simlilar to the 'rosepetal' nozzle used in Australia.
Giesls on an articulated would result in a VERY long smokebox compared to class A-style dual stacks (assuming you are keeping the two exhausts separate). On a compound you might get better performance -- but exhaust drafting is less complicated, and high-speed back-pressure reduction of lower criticality, on something like a Y6b the way N&W ran them.
I wonder how it compared to what Union Pacific was doing with their consistant use of "double smoke stack" steam locomotives. I believe UP844 is double stacked.
I presume you would love to know that the FEF-4 design was supposed to have FOUR stacks -- arranged as on the PRR S2 turbine.
I do have to think this was overkill in practice. The FEF-3 was one of the locomotives in the '30s that would actually produce insufficient draft when cut off most effectively with low effective back pressure; a double stack 'sized to fit' only makes that problem worse (cf. British practice). If you look at some of the more 'unusual' experiments with multiple stacks (e.g. the R-class Hudson mods in Australia, with some VERY odd stack arrangements) you may get some better ideas regarding what's needed. (PLUG -- read Jos. Koopmans' book)
To an extent, the need for double stacks is driven by a need to increase exhaust volume beyond what a single stack of sensible diameter can deliver. The Giesl accomplishes this by using longitudinal extension rather than multiple pipes. Some of the 'optimization' of multiple stacks involves the use of intermediate vanes or ducts (like those in a Kylchap nozzle) or a flow-separation device like what Porta called a "Kordina". One large stack gives the necessary area, but the entrainment parameters are all wrong above about 15" diameter without a central 'forebody' or use of an annular configuration.
RME
Examples: http://www.trainweb.org/tusp/ex_dwgs.html
.
If memory serves me right, there was an article in TRAINS more than a few years ago ("Which Twin Has the Giesl") about Dr. Giesl and his front-end design. The article mentioned that the only locomotive in the United States to be equipped with a Giesl was C&O 191, an 0-8-0.
Paul, your memory is good. I, also, do not recall the date of the article, but it was in the fifties, as I remember.
Johnny
It was more recent than the fifties. I distinctly remember it from the mid-60s, as it was a VERY formative influence in my education in locomotive design.
Should be very easy for anyone with a Trains DVD to point us at the right reference. (A shame that the online search is so hobbled that it does not produce a legitimate hit on the search term "Giesl")
UPDATE: The magazine index does have it. January 1968. (Giesl-Gieslingen himself has an article from July 1980, that I do not recall having read!)
Yes, I really DO need to order my DVD... might go do that now. If I can find the order form on the site. Yellow footer, push ads, search bar and all... nowhere can I find the link to the digital back-issue-collection DVD. (Mods and Kalmbach: if you want a sale, send me the link...)
Now we're at the point I wish Juniatha would weigh in on this. Her father met Dr. Giesl years ago and had quite a conversation with him which she remembers very well, on steam design and a few other things.
Firelock76 Now we're at the point I wish Juniatha would weigh in on this. Her father met Dr. Giesl years ago and had quite a conversation with him which she remembers very well, on steam design and a few other things.
I happily concur with this idea -- but please, the man's name is Giesl-Gieslingen. (And I believe his title, though he was an 'honorarprofessor', should be Prof. Dr.)
These things matter!
(I would have PMed this, but I couldn't find the link to do it from your post!)
Ja, ja naturlich Herr Overmott, howeffer Doktor Giesl iss goot enuff vor chenerall purpozzes, nicht wahr?
Flintegewehr76
Ja, 'stimmt, aber der Preferenzen der Mann selbst musst uberall die Regeln machen. Und Onkel Adolph war stolz seinem Name. Wurde man sagen "Bel" fur die Kessel, aber "Walsch" fur die Heusinger- Ventiltrieb? Wie Morike kann wir sagen 'Nicht geheuer muss es sein'... nicht wahr, wahrlich!
Entschuldigen Sie fur die zerbrochene Sprache, verwend'ich diesen ausgezeichneten Referenz von Konrad Dudelsack, die 'Vollkootische Wortlosbuch" (Be)schweren zu ihm, nicht mir.
Wahrend wir mit den verruckten Namen betroffenen, sagen Sie "Uber-Mod". Vielen dank.
Ach so, Ich verstehe.
Show-off!
Firelock76 Show-off!
'Schuldigung! (I confess I am trying to entice Juniatha out, even to comment on schlachterei of her native tongue. Hopefully I will not have to go as far as quoting Twain on the subject to accomplish the desired results...)
Overmod Firelock76 Show-off! 'Schuldigung! (I confess I am trying to entice Juniatha out, even to comment on schlachterei of her native tongue. Hopefully I will not have to go as far as quoting Twain on the subject to accomplish the desired results...)
Deggesty Do you mean to dive into a sentence and come up at the end with a verb in your mouth?
Do you mean to dive into a sentence and come up at the end with a verb in your mouth?
Exactically.
Whatever, please do not attempt to emulate the Connecticut Yankee as he banished the demon that had stopped the water flowing from a well.
I do not need to attempt to emulate a Connecticut Yankee, as I am one by descent on both sides (if you don't count a little Yankee-Pennamite action on the losing side). But relax! I don't have the right font on my system to do the incantations justice...
I will, however, provide a couple of translations, to give all of you not yet 'experienced' the sense if not the feel of the thing:
"The Constantinople Bagpipe Manufacturing Company"
"Attempts by nihilists to blow up theatre boxes using dynamite"
"The tear-jerking tragedy of the wedding of the camel driver from the Transvaal troops' tropical transport unit"
Overmod Deggesty Do you mean to dive into a sentence and come up at the end with a verb in your mouth? Exactically. Whatever, please do not attempt to emulate the Connecticut Yankee as he banished the demon that had stopped the water flowing from a well. I do not need to attempt to emulate a Connecticut Yankee, as I am one by descent on both sides (if you don't count a little Yankee-Pennamite action on the losing side). But relax! I don't have the right font on my system to do the incantations justice... I will, however, provide a couple of translations, to give all of you not yet 'experienced' the sense if not the feel of the thing: "The Constantinople Bagpipe Manufacturing Company" "Attempts by nihilists to blow up theatre boxes using dynamite" "The tear-jerking tragedy of the wedding of the camel driver from the Transvaal troops' tropical transport unit" There were some even better ones in an old Ripley's Believe it or Not compendium I loved to read when I was a boy. One of them, if memory serves, was 226 syllables long, and you needed breath control like Bill Clinton playing a piece by Barbara Thompson to get through it intact...
Was the 226-syllable name that of a station in Wales?
On a more serious note, I came across a picture of an event which led to the 611's being chosen for preservation; it is on page 46 of the March 1999 issue of Trains. The picture is of 611 on her side at Cedar Curve, west of Bluefield. Because the N&W saw fit in January of 1956 to completely overhaul the engine after the wreck, she, of all the J's, was in the best shape, and so was preserved. The same article tells of the running of 600 from Bristol to Roanoke on just one side, with only the side rod intact on the dead side.
Deggesty Was the 226-syllable name that of a station in Wales?
No. But go here for everything you need on that subject...
We had a recent thread -- here, I think -- that included the running on only one side. With claims that over 90 mph speeds were reached in places. Does the article specifically mention any such details?
Since she was born in the US, I believe her native tongue was likely to be English (it's possible that she may have spoken Deutsch at home).
erikemSince she was born in the US, I believe her native tongue was likely to be English (it's possible that she may have spoken Deutsch at home).
I was taking it at face value when she described herself as 'a German girl'.
The effort so far to get her, herself, to comment seems to be remarkably unproductive.
Overmod Deggesty Was the 226-syllable name that of a station in Wales? No. But go here for everything you need on that subject... We had a recent thread -- here, I think -- that included the running on only one side. With claims that over 90 mph speeds were reached in places. Does the article specifically mention any such details?
Here at the Fortress Firelock I've got an old Pennsy engineman's rulebook (somewhere in the pile) which mentions running on one side. Yes, it could be done. However, this was to be done only as an emergency measure to get the locomotive to the nearest servicing facility if a tow wasn't available. In no way were 90 mile-an-hour speeds possible. I don't even see how they could even be thought of, even if the locomotive in question was capable of that speed with everything being right to begin with.
I think it's safe to assume the N&W operated under the same rules, or rules very similar.
Firelock76 Here at the Fortress Firelock I've got an old Pennsy engineman's rulebook (somewhere in the pile) which mentions running on one side. Yes, it could be done.
Here at the Fortress Firelock I've got an old Pennsy engineman's rulebook (somewhere in the pile) which mentions running on one side. Yes, it could be done.
( ... Wouldn't it be an armory, not a fortress, if its primary purpose is to house firelocks? ...)
Could be done, and was done, regularly. Many of the books on locomotives and management mention methods for taking down one side, blocking the relevant parts, and even what materials should be available. I believe there is a section in the ATSF locomotive and running manual (downloadable on the Web) that describes this for modern locomotives.
One interesting detail is how the train, and the engine, are moved to get off a dead center ... some interesting aspects to this. Another is how you conduct 'triage' -- first try to get your train to the nearest siding in minimum time, then try it with smaller load (since you only have in principle 1/2 the original tractive effort), etc. The ATSF book also mentioned conditions under which it did NOT make sense to work the engine on one side, some of which were a bit surprising.
It would be interesting, if not amusing, to see this spirit applied to primary engine failures on diesels. (There are accounts in Trains of how diesel engineers would carry transition relays and various and sundry other tools and parts in their grips to keep locomotives running on the road (regardless of the Brotherhoods and unions who might probably have grievances about this if known...), and of course the early history of diesels contains references to built-in hoists and beam cranes for changing out cylinder heads and pistons -- but that was usually done by riding maintainers, not the crew themselves.
However, this was to be done only as an emergency measure to get the locomotive to the nearest servicing facility if a tow wasn't available. In no way were 90 mile-an-hour speeds possible. I don't even see how they could even be thought of, even if the locomotive in question was capable of that speed with everything being right to begin with.
Now, admittedly, the J was a special case because it was intentionally balanced to have zero overbalance, so taking down a main would have less effect on running characteristics than 'usual'. And the absence of the center-of-percussion rotating mass, in lightweight rods, would have comparatively less effect on rotational balance (and tendency to augment) on the affected side -- assuming they put as much of the eccentric crank, etc. components back up after pulling the main. Interestingly, if a 'bobweight' equal in mass to the rotating component of the main and valve gear, with its center of lateral mass aligned with the resultant for the intact configuration, could be provided in the field, yes, the engine would run effectively balanced up to high speed (the unequal 'surge' being neatly accommodated in the same way recip imbalance was accommodated...
But I found the anecdotal report of 90 mph speeds (even though this was on the ATC-equipped Shenandoah Division) not particularly likely, if not nearly criminally irresponsible. I was fairly bitterly attacked for questioning the veracity of those speeds. And I was not there, so who am I to say it did not actually happen?
I did request a source for the story, which was never provided. This Trains article now provides one. Unfortunately, I can STILL not find the link to purchase the back-issue DVD (hint, hint, again!) so I do not know the reported details -- can anyone paraphrase in detail?
Overmod, if you're looking for the Trains back issue DVD go to www.kalmbachstore.com. On the right hand column/menu select "railroading", when you do another column will pop up, select DVD's, it's right there.
PS: This is the "Fortress Firelock" 'cause we;ve got a lot more crap in here than firelocks! More I will not say...
The article (which is about then yard/shop Foreman Clyde J. Taylor of the N&W) which showed the overturned 611 also has the account of the 600's trouble when the left side valve gear disintegrated--and states that there was nothing remaining of the left side valve gear after the Bristol shop worked on the engine, preparing it for the trip to Roanoke.
The speed limit on that section of the Radford (not Shenandoah, which was in the Shenandoah Valley, north of Roanoke) Division was 65 mph for passenger trains, and the article states that #45 was running at 65 mph when the valve gear began coming apart. At least one of the men on board the 600 stated that when #45 met the 600 the passenger train was running probably more than 80 mph (remember that in those days not all, if any of the details of a train's run were reported to the ICC); perhaps she was running late. There were sections with lower limits, but, as well as I can tell from the article, the section on which 600's speed reached 80 mph had the timetable limit of 65 mph, yet it was a section on which engineers often made time up by runnning fast according to the article. Apaprently the engineers trusted the roadbed and the curves.
As in the original posting of the one-sided running, I have stated what the article said. I did not feel bitter when responding to your questioning what the article stated, but wanted to affirm that I had not embroidered the account. I believe that in my response I corrected my original quotation of the speed attained, which was reported to be 80 mph (at least 15 mph greater than the speed limit) and not 90 mph.
Oh, Radford Division Time Table #4, Sunday, April 26, 1953, does not mention ATC but Traffic Control between Walton and Bristol (double track with automatic block between Roanoke and Bluefield).
As to running faster than the ICC limit, I have personally timed miles at 35 seconds to the mile on track with a 79 mph limit, and I have ridden an engine with the speedometer needle staying at 90 mph for most of a distance of 100 miles, except for a scheduled stop about half way, also on track with a 79 mph limit (both times in the 1960's).
This, then, is the critical detail: it was the valve gear, and NOT a main rod, that was taken down?
I had thought from the previous context (or perhaps mistaken assumption) that the article was describing working the locomotive with the main taken down. Balance and running considerations would have been far less 'dangerous' if only the eccentric rod were missing (the other rodwork and pieces in the Baker gear not contributing measurably to balancing). This leaves only the question of whether 'nothing remaining of the left side valve gear' included whatever was left of the eccentric crank (which I cannot imagine was removed, as even the hub with crank busted off would aid in rotational balancing).
Yes, with both mains and crank, I can easily see the engine being run up to the reported speed. The balancing contribution due to the 'asymmetrical' rod thrust would be in the thousands of pounds, easily accommodated by the overbalance compensation in the trucks, and the (missing) vertical component of that thrust would be a minimal fraction of that, if anything making the engine better balanced on the dead side...
I did not mean to question achievement of 90mph speeds in service with the Js, as that indeed was a matter between N&W and the ICC of a kind often 'selectively reported'. I was basing the presence of ATC mostly on King's report that the A class did not operate over the Shenandoah Division because unequipped with ATC (do not have the page number for cite). For some reason, probably ignorance, I had thought the Radford Division and the Shenandoah Division had the same characteristics. I do not have access to the list of where the ATC installations were... but I would easily agree that the northern end of the Shenandoah Division would be where I'd expect to find it. (And not south of Roanoke where I'd see minimal value for an experimental-scale ATC test comparable to those mandated before 1928...)
There is, of course, no question of Js being able to reach a road speed of well over 100mph with train (cf. testing on the PRR, seized valve or no!) Neither would I question whether N&W track construction and geometry (aside from curvature and perhaps superelevation) would be a limiting factor on achieving high passenger speed. (Or that 'timetable speed' could or would be exceeded, even if only by the nudge nudge wink wink, knowwhatimean method, if an important train were late...) My objection was based on the idea that the main rod, not the eccentric, was the 'missing part', further complicated by not knowing that Bristol shop personnel had looked over the engine and approved her being run at high speed.
The issue with the 'dead side' power would apply much more to starting and low-speed-surge considerations than high speed power. I would in fact expect that much of the "power" at higher speed would still be available, by keeping the cutoff comparatively long and thereby developing more power in the cylinder per stroke, perhaps even with minimal impact on the water rate (since only one cylinder would be consuming steam) Might be interesting to calculate exactly what settings would have been used -- does the article discuss any of that?
So yes, I no longer disagree with the story as amended. Thanks.
I'll quote directly from the article: "Back at the roundhouse [in Bristol], shop forces removed the massive main rod and what was left of the eccentric rod [which had broken; the culprit in the event?]. Rather conspicuously in place was the side rod. They also blocked the piston and secured the main valve for the trip to Roanoke Shops."
That the main rod was removed made me wonder about balance and pounding the rail--and the roundhouse foreman Clyde Taylor, also wondered : "'I figured it would rock and raise h***, but no...it just ran fine. You wouldn't believe how well it ran. It was smooth as silk.'"
If 611 is returned to use, may her valve gear (and all other parts) hold up and not come apart as the sixteen-year-old 600's did fifty-seven years ago.
We need numbers that I don't have.
Specifically, what IS the revolving component of the mass of one of those Timken mains (complete with bearing and races; they wouldn't have left them on)? ISTR that one of those rods only weighs about half a ton, and the revolving portion of that might be around the '1/3 rule' even if we don't have center-of-percussion data.
The problem that comes up, though, is that the J with comparatively low (70") drivers is going to show inertial imbalance effects more quickly, when you get up into the range where the inertial force becomes comparable to 1/2 the main axle load -- that's where the bouncing-driver part gets started. If we know the revolving pass (or even a reasonable approximation from known sources) we'd have a good idea of how fast the engine could spin, and from that get some idea of permissible/safe speed.
I have drawings of the rods from the historical society, but cannot get at them in at least the next few days. I'm not even sure these carried the distribution numbers for a center-of-percussion test (although you can bet one was done, and competently...)
Goes back to Kiefer's mention of slip-testing the Hudson (I would think probably with lightweight roller rods, but I don't know for sure) up to the equivalent of 161 mph without observing pound or bounce. I'm beginning to wonder whether it is very surprising to see half that speed (which is 1/4 the energy) achieved by an engine 'out of balance' by only a few hundred pounds. Again, running the numbers will tell the tale.
Check your e-mail.
DRS
Slightly off topic here but didn't the 6315 break the eccentric rod which was then removed while double heading with 5632? I've heard that 5632 pushed it and pulled the train for the remainder of the trip, but wasn't sure if the story was true or if 6315 remained active on the last leg.
RME,
It has been a thoughtful exchange! You act as if you have spent some time in steam engineering. The weight of the eccentric rods on PM1225 is not as heavy as you would think. I can lift the entire I beam rod with one arm. In fact PM1225 has the eccentric rod from another PM1200 as the parts were apparently mixed in rebuilding. PM1206 if memory serves me right. I believe NW611 could run with that rod missing and the valve blocked in the fashion described. Speed in this condition would seem unwise.
I did a thumbnail comparrison of some horsepower figures for NW611 compared to others. This is a quick research and I was not careful with DHP and IHP figures so there is room to argue here.
NYC 4-8-4 6,680 horsepower
PRR 4-4-4-4 6,550 horsepower
NW 4-8-4 6,000 horsepower
SP 4-8-4 5.500 hp
C&O 4-8-4 5,000 hp
AT&SF 4-8-4 4,590 hp
UP 4-8-4 4,700 hp
NYC J3 4-6-4 4,700 hp
NYC J1 4-6-4 3,900 hp
PRR K4 4-6-2 3,500 hp
Of course horsepower is not the full measure of any maching, it is also the ability to sustain that power and the wear on the machine that produces it, as well as the speed at which the power is produced. These are all mainline passenger engines designed for speed and endurance. The power produced by Paul Keifer surely shows the work of a master. I wonder if AT&SF really ever developed their design, as it should have had the most potential with its size. Obviously C&O and the N&W were cousumately well designed although C&O track record with the 2-6-6-6 shows it used its steam power as designed and did not develop the potential either. NYC has to be the champion at taking the time to evolve the machine to its height. NW611 should be in this catagory as they built the engine from the ground up as well as developed its design.
Other steam locomotive horsepower rating in passing are the power champion PRR 4-4-6-4 Q2 I believe this design was not considered a success from the maintance standpoint and was clearly out matched by its rival PRR 2-10-4 design in this capacity.
PRR 4-4-6-4 7,987 horsepower
C&O 2-6-6-6 7,500 horsepower
PRR 6-4-4-6 7,200 hp
PRR 6-8-6 6,900 hp - direct drive steam turbine
N&W 2-6-6-4 6,800 hp
UP 4-8-8-4 6,290 hp - Big Boy
DM&R 2-8-8-4 6,250 hp
UP 4-6-6-4 6,200 hp
SP 4-8-8-2 6,000 hp - cab forward design
N&W 2-8-8-2 5,000 hp - compound mallet design
AT&SF 2-10-4 5,000 hp
UP 4-12-2 4,700 hp
Steam engine power was a product of the design of the engine as well as the skill of the engineer at operating the machine. Quality of coal, oil and water all affected the performance daily.
In this chart, these engine statistics form an overall comarrison that spans the "drag era" freight design to the "dual purpose" super power design. When Isaac Watt developed the "horsepower" measurement designation it was to tell us a basic facts about potential for performance.
Dr. D
Steam locomotive horsepower figures have been discussed ad nauseam here in the past.
Virtually all the figures found in books and on the net are very suspect and inflated, and except for a few, cannot be trusted.
Agreed about at least one previous and protracted discussion, perhaps four years ago already. I think I recall a poster who seemed to know steam locomotives well saying that a UP Challenger could produce something like 3700 hp at about 50-60 mph, or something near that.
Crandell
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