Hello,
can somebody provide me with a Tractive Effort and Horsepower vs. Speed table for "Big Al"?
Any other big steamers are welcome!
Lets say for speeds
0-10, 10-20, ... up to 70mph?
Thanx in advance!
Lars
Lars,
Check your PM's. I have some of the info you want.
this site has some good info on various classes and survivors
http://www.steamlocomotive.com/
The Y6b is king of the eastern hills. The TE of that engine will move earth backwards in it's orbit if permitted to do so.
The Alley was wasted on the ups, downs and sideways. Hardly it has room to get up and run.
The western folks always had to go up hill or downgrade. They dont know any better. (Just teasing. lay off will ya?! LOL)
Got the info, thank you so much!
Quote:
"The western folks always had to go up hill or downgrade. They dont know any better. (Just teasing. lay off will ya?! LOL)"
No way, they knew better! But design concepts for the east, may not work as good for the west (and vice versa).
lars
The Y6b moved mountains in the east but could not keep up out west on a schedule with the Bigboys running 50 mph and a mile of Produce.
However the Bigboy would be most difficult to use in the east for a variety of reasons.
Horsepower = work availible in a unit of time. If there is additional horsepower availible near the top end then you can use it. If you used all of your horsepower to get to the top end and have nothing left over... well that all you got.
I am not exactly a horsepower man but more of a torque man. Once long ago my 300+ horse engine 3700 pound bomb of a car was defeated by a big block buick 4 door 6000 pound convertable off the light. If I had about a mile I could show him horses but doubt it. Not in that particular situation anyhow.
Falls Valley RR wrote:The Y6b moved mountains in the east but could not keep up out west on a schedule with the Bigboys running 50 mph and a mile of Produce.
They could! Y-6 was permitted to run 50, and within this entire speed range tonnage ratings were higher than for Big Boy. Impressive what a tiny percentage of running time Big Boy was used above 50mph...
"However the Bigboy would be most difficult to use in the east for a variety of reasons"
Hmm, they were too long for easten turntables and their clearances?
I think on a performance level, they could do any job, but few engines could do the job of BB. At the Ogden - Wasatch - Green River - Ogden-run (more than 300miles, for 11 years ) they would be difficult to beat. And could haul 3250t@1.55% at 15-20mph
"Quote"
"They could! Y-6 was permitted to run 50, and within this entire speed range tonnage ratings were higher than for Big Boy"
High tonnage was given to the y6, and they were very efficent to manage it. But I think it is not correct to justify the engines just by the tonnage they pulled. Do Speeds beyond 10mph really account? Theoretically, at speeds more than 10mph, the BB is quite similar to the y6(b?) and has advantages above 30mph. Then, pretty much between the Alley and a Class A (by comparing their tractive efforts and hp tables). The average speed for an Evanston - Green River, or Laramie - G.R. run was more than 30mph, including stops. Extras would be faster. And they run could 70mph? Why? 'Cause just could do so ;-)
UP just crossed a x-6-6-x with a x-8-8-x, concerning TE, Speed and HP, didn't they?
VAPEURCHAPELON wrote: [N&W] Y-6 was permitted to run 50, and within this entire speed range tonnage ratings were higher than for Big Boy.
What were their tonnage ratings at 50 mph?
Don't know how tonnage ratings would comapre on different profiles, but the drawbar tractive efforts (in pounds) for the Allegheny and Big Boy are as follows:
Speed Allegheny Big Boy
10MPH 105,000 128,000
20MPH 92,000 98,000
30MPH 75,000 72,000
40MPH 60,000 56,000
50MPH 48,000 40,000
The numbers for the Allegheny were derived from the graph on the upper left hand corner of page 204 of Huddleston & Dixon's book, while the numbers for the Big Boy were derived from the graph on page 20 of Kratville's book on the Big Boy - the graph for the Allegheny had better resolution than the graph for the Big Boy.
I would expect the Y-6b to be (ahem) running out of steam at 50MPH.
I took your table and inserted the numbers for the Y6b that I derived from the N&W graph reproduced in "Norfolk & Western Steam, the Last 25 Years," Ron Rosenberg, Quadrant Press 1973, which compares the Y6b, Class A, and steam-turbine electric.
Speed Allegheny Big Boy Y6b
10MPH 105,000 128,000 121,000
20MPH 92,000 98,000 94,000
30MPH 75,000 72,000 63,000
40MPH 60,000 56,000 33,000
50MPH 48,000 40,000 N/A
The graph cuts off for the Y6b at 40 mph, for the steam-turbine at 50 mph, and the Class A at 60 mph, which would seem to indicate that the Y6b was not meant to deliver useful work at speeds in excess of 40 mph.
RWM
"Quote":
"Y6b was not meant to deliver useful work at speeds in excess of 40 mph"
And is not it just the reason, the N&W had in addition the Class A, too?
@clash: I guess the Coal from Hanna and Rock Springs (Food for the BB) is lower qualitiy and would not burn so efficient. Ok, don't have a qualified source for that, but I read once that the coal in BB's firebox would never touch the grate, 'cause burned so quickly. A deeper firebox, feeded with suitable coal, may spread and keep the heat better... However, the y6 keeped its firebox above the rear drivers, same BB. Maybe the Y6 would do better with low grade coal than an "A" ? But how much relevant is an 10% -20% difference between the heat content related to hp? 200-300hp?
This was discussed a month ago at http://trains.com/trccs/forums/1304887/ShowPost.aspx
Average values are:
That doesn't necessarily mean that the locomotive burning 14,000 BTU/lb. coal is automatically 10% more powerful or more efficient than a "similar" locomotive burning 12,600 BTU/lb. coal or even the same locomotive burning 12,600 BTU/lb. coal. I know absolutely nothing about steam locomotive firebox design, firing rates, or boiler efficiency.
To Railway Man:
did not notice this thread earlier, much information there which will take some time to get through it. Thank you!
It is not the ability of coal to burn "More or less" powerful but the overall design of the boiler to feed the cylinders.
Take the Triplex. Impressive eh? But it pants and runs out of steam anywhere above 30.
You are simply heating a huge amount of water to boiling and then beyond. That is all there is to it. Dont overthink or hurt yourself trying to determine if one is better than another.
All engines will max out somewhere at max hp and will not give you any more no matter what you pour into it.
Now having said that, I expect folks to jump on here and show me a 350 cat buffed with 4 turbos, pressuriezed fuel systems and extreme output capable of taking 50 ton up a 7% grade at 70+ mph and have horses left over to accelerate.
It may not have the fuel to make it over the top with such large amounts of fuel (Energy) being fed to it.
Also keep in mind that the Y6b was a Compound and probably operated somewhat differently than.. say a Big Boy that was taking steam in all 4 cylinders as it came from the boiler without reusing any of it.
Finally but not last, consider the 4-4-4-4 Duplex from the PRR. Engineers swore they were slippery and worthless but wispered about thier 100+ mph performance with lots of horses to spare but no room left. Fact? Legend? Myths? You tell me.
40 mph is good speed for steam. In fact, I think today's engines with thier impressive performance STILL run trains at average of 40 mph. Maybe Im wrong.
Or consider the B&O "Big Six" those were doing service doing Passenger Helper service at 30 mph or so.. UP HILL.
"It is not the ability of coal to burn "More or less" powerful but the overall design of the boiler to feed the cylinders."
I meant it in a way of efficienty, that certain firebox design's are nesseccary for certain kinds of coal and can improve overall efficiency dramatically. "The firebox was one of the not good designed parts of BB", to literally repeat Kratville about what he write in his book. Built as a compromise, but could deliver enough power if you get used to it. However, ' never saw any of the Western Roads ever used those deep "Super Power" boxes. Burning Oil was another alternative for them, also.
"...4-4-4-4 Duplex from the PRR. Engineers swore they were slippery"
Because the engineers did not know how to handle this new kind of machine.
"Take the Triplex..."
On hot summer, the cap of a Triplex was the coolest place ;-)
Regardslars
This is moderately OT, but it supports Lars statement regarding PRR T1 handling problems and provides a documented example of variable skills of enginemen. Here's a quote from a PRR internal memo dated 9/29/45 (from Hagley Library). I thought it would make interesting reading:"After we had taken sand at Conemaugh the engineman had the train moving and if he had left the throttle in its position, the locomotive would have hauled the train away, but he jerked it open, the locomotive slipped, the train stalled and we had to put a pusher on to get the train away."This quote was take from a report by Asst. ME Decker who was riding the locomotive during an extensive over-the-road test period where 6110 and 6111 were being used on regularly scheduled trains.Previous paragraphs in the same memo describe this engineman's insistence on using a heavy throttle during poor rail conditions east of Pittsburgh, where he allowed the locomotive to slip so badly that Decker stated:"...I was afraid we would do some damage to the locomotive before the engineman noticed the slip and closed the throttle."On the other hand, given one of the best crews, things were different. Just three days before the above run, #6110 took a 21-car passenger train over the Middle Division, rain and fog the whole way, with two slips recorded between Harrisburg and Altoona. They left Harrisburg six minutes late and arrived two minutes early at Altoona. There were at least three intermediate stops and no difficulties were encountered at any of them. This run is described in PRR memo dated 9/24/45. It is based on a report by a Special Duty Engineman who was riding 6110 during the run.The above contrasting operations were recorded during a two month test period during Sept and Oct 1945. Most or all of the reports of runs during this period have survived. How the crews operated the T1's had a major impact on their performance.
I think on a performance level, they could do any job, but few engines could do the job of BB..... And could haul 3250t@1.55% at 15-20mph
Over the Blue Ridge grade, which would be very similar, the Y6 was rated at 4600 tons in slow freight and 4100 tons in time freight service.
50 -55 mph speeds on a Y6 were not uncommon. As a steam engineer related to me, 63 mph was about as fast as you wanted to run a Y6. After that things started to get a little shaky. So the problem a Y6 would have would have in keeping up with a Big Boy would be more from the inherent dynamic forces and speeds in the running gear brought on by the smaller drivers.
As for running out of steam, with good coal, N&W's big three had no problem with steam production. Engineers have also told me that even in simple, the Y6 had no problem keeping a full gauge of steam and could even lift the pops.
Too bad Road & Track magazine didn't do performance tests (like they did with the Strasburg Decapod one April) on steam locos when they ruled the rails.
.
BigJim wrote: I think on a performance level, they could do any job, but few engines could do the job of BB..... And could haul 3250t@1.55% at 15-20mph Over the Blue Ridge grade, which would be very similar, the Y6 was rated at 4600 tons in slow freight and 4100 tons in time freight service.50 -55 mph speeds on a Y6 were not uncommon. As a steam engineer related to me, 63 mph was about as fast as you wanted to run a Y6. After that things started to get a little shaky. So the problem a Y6 would have would have in keeping up with a Big Boy would be more from the inherent dynamic forces and speeds in the running gear brought on by the smaller drivers.As for running out of steam, with good coal, N&W's big three had no problem with steam production. Engineers have also told me that even in simple, the Y6 had no problem keeping a full gauge of steam and could even lift the pops.Too bad Road & Track magazine didn't do performance tests (like they did with the Strasburg Decapod one April) on steam locos when they ruled the rails.
Jim, have many thanks for this nice posting. Thanks to feltonhill, too.
Please let me throw in another thing: I guess it's sure that N&W's great three steamers even could put out the same amount of steam and therefore hp with fuel of lesser quality than they actually used. They may have needed more fuel then, of course. But firebox volume and grates were very large on all three designs, it's simply unlikely that there would have been steaming problems. Maybe that would have required other grate bars and air intakes etc., but the engine's design would not have been a problem. There were plenty of steam engine classes running with different kinds of fuel without any influence of power output. On the other side - because this still won't die - if Big Boy would have used better fuel it just won't have put out more steam or hp, but would have used less fuel, nothing more.
To all who posted yesterday & today : this thread has been very informative . One would say all the engines did their job as desined,subject to the whims of the engineer and all the variables at hand.
Thanks to all of you. Respectfully , Cannonball ( another Jim)
Y6bs evergreen in my mind
First of all, thank you Everybody for putting more info here!
@BigJim:
What is the grade at Blue Ridge, and how long is it? Do not have any sources for that, only for Sherman and Wasatch. However, if train speeds exceeds 10mph, both should have the ability to haul same weight . 3250 tons is not bad, maybe Y6 or some other could pull some more, but their TE-Table does not show it that clearly ( I only can rely to this, sorry for being blind on one eye! ) Most would pull far less. A "H7" was rated 2400tons, a Challenger 2100tons.
To be honest, I am little bit confused on Y6 datas, you can help me for sure: I only have the TE-Table for the Y6, which Railway Man posted earlier on this thread, though I read higher values. The graph compares an "A", a "Y6b" with "Jawn Henry". It is likely therefore, it relates to the later, refined Y6b. It starts with 170.000lbs, and drops to 125.000@10mph. After it it smoothes down:100.000@20, 65000@30. Guess this is all simple expansion. Compound would lower the TE-Curve, right? However, builders specified starting TE was just 152.000 (simple) and 126.000lbs in compound mode. Read once, they had something around 190.000lbs (Massena's, Kings's thoughts?). Which one is true? And, the Y6 had certainly the abilities to run more than 50mph (short time?), but based on a day-in day-out schedule or at a 100mile run? Do not think it is a good idea. Maybe the later, refined Y6b could do so?
@VAPEURCHAPELON:
I totally agree with you the N&W engines would not run out of steam at all but it would affect engines permormance: Reading your post, can we conclude, a given firebox, mated with an appropriate boiler, will always deliver a certain output until its max. is reached? And only the firing rate varies? Confuses me, 'cause weren't oil-burners in general more powerful? I think about the German post-war DB01, DB45, ... classes, the difference between coal and oil was ~200hp on these 2000hp engines. Is that caused from heat content of oil, or do other things play a role? However, 200hp more or less for a 5000-6000hp class engine would a be small percentage, but 10%?
Looking forward for Your answers!
P.S:
You may find the graph at http://locofonic.alphalink.com.au/te1.htm
Lars, if the graph you are looking at for the Y6b indicates a starting tractive effort of 170,000 lbs, then that at least purports to reflect their final form. (By the way, most if not all of the Y5 and Y6 class locomotives eventually got most if not all of the improvements.) If it falls as far as 125,000 lbs at 10 mph, then to me that suggests either pure compound operation, or at least basically compound operation with just a little boost from the somewhat complex N&W system.
Frankly I would be somewhat surprised that a y6b's tractive effort would fall so far at such a low speed. I am not sure whether there was some problem that essentially prohibited simple operation at more than a few mph, or there was a problem generating enough steam to keep up with the demands of those big front cylinders, if you feed them with high-pressure steam directly from the boiler (instead of mostly once-expanded steam from the rear, high-pressure cylinders).
Generally, I think we can say three things with a high degree of confidence: (1) the Big Boy was much more of a high-speed design than the Y6b, and could run faster; (2) the Y6b could start, and pull at low speeds, a considerably heavier train than a Big Boy could; and (3) a Y6b can pull a train fairly fast (50+ mph), but is outside of its design envelope at 60+ mph.
P.S.
The only steam-piston locomotives that had tractive efforts in the 190,000 lb range were experimental, and basically failures: some of the triplexes. The highest starting tractive effort from a successful, regular production steam-piston locomotive was, IIRC, about 176,000 lb from the Virginian XA 2-10-10-2's.
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