PRR Duplexes and Experimental Engines ( S1, S2, T1, Q1, V1 etc.)

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Posted by Hermann on Tuesday, April 21, 2020 12:46 PM

Jones1945
S1 stayed in the shop quite often, but whenever she was "recharged," she exclusively hauled some of the most important named trains of PRR (General, Trail Blazer, Golden Arrow) instead of "lower tier" passenger trains. PRR made the best use of her, unlike the T1 and Q2...

Yes, and/but from March 26, 1945, the S-1 even got a competitor in 6200, which usually ran the Trail Blazer east and the Admiral west.

 
As far as I know, before the 1472 days-regulation came into place (tayloured to the heritage RR's needs), the FRA had a locomotive inspection law which ordered the removal of all flues every 48 months within 5 consecutive years, but that period could then be prolonged by the boiler inspector for one year, for one or several times.
 
I do not know, however, if these regulations were valid all the time from their installation in 1911, or if there had been changes due to wartime or so. And I don't know how the term "consecutive" years might have been interpreted for a locomotive which spent good parts of two years as a display.
 
By the way, the site of the old Crestline roundhouse is still for sale!
 
There is an article in German, just a few years old, claiming that GM had acquired essential parts of PRR shares in 1945. Are there any primary sources confirming this?

 

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Posted by Jones1945 on Thursday, April 23, 2020 4:14 AM

Hermann

Yes, and/but from March 26, 1945, the S-1 even got a competitor in 6200, which usually ran the Trail Blazer east and the Admiral west.

The S2 also hauled lots of crack trains that the S1 seldom pulled, like the Broadway and Manhattan limited. I read somewhere that people saw the S2 once appeared in Pittsburgh, the "forbidden city" of the S1. On the other hand, I have seen pics of  the T1 phototypes powered the Trail Blazer. 

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Posted by Hermann on Wednesday, April 29, 2020 2:43 AM

Jones1945
The S2 also hauled lots of crack trains that the S1 seldom pulled, like the Broadway and Manhattan limited. I read somewhere that people saw the S2 once appeared in Pittsburgh, the "forbidden city" of the S1. On the other hand, I have seen pics of the T1 phototypes powered the Trail Blazer.

 

Hi Jones1945,

interesting thing that for three long years, the two prototypes ran into and through Pittsburgh without any reported troubles.

Only in Summer 1945, the first derailment took place im Pittsburgh. Then, just one month after delivery of the first serial T1s, 5502 derailed on December 1, 1945, and another serial T1 the very next day.

Did somehow, tragically, the two prototypes have the edge over the 5500s in curves?

 

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Posted by daveklepper on Wednesday, April 29, 2020 3:07 PM

Or is it possible that the track was not as well maintained?

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Posted by daveklepper on Wednesday, April 29, 2020 3:20 PM

I  rode behind a T-1 on the Trail Blazer on my way to work for EMD in late June 1952 into Chicago.  Do not kbow if it came from Hattisbutg, Pittsburg, or Cteatline.

And, then, which I now find was rare, behind a GP-7 to La Grange.  I think I was able to rent a shower room at Union Station before boarding the Q's scoot, which had the GP-7, generatr car, and two Budd galleries.

All trains were on-time but for arrival in Chicago a few minutes early.

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Posted by Hermann on Wednesday, April 29, 2020 3:51 PM

daveklepper
I rode behind a T-1 on the Trail Blazer on my way to work for EMD in late June 1952 into Chicago. Do not kbow if it came from Hattisbutg, Pittsburg, or Cteatline.

 

Hi Daveklepper,

as to Charlie Meyers reports, your train should most probably have been powered Harrisburg - Pittsburgh by a T1, Pittsburgh - Crestline by a double set of K4s and Crestline - Chicago by a T1.

After the Pittsburgh derailments in summer/december 1945 and about March 1946, some design changes were made to get a bit more lateral movement on the driving axles so that the T-1s could go into Pittsburgh, but still could not pass the curve west of the station safely. Ironically, the curve was relaid after the T-1s were gone.

 

And late June 1952, you were lucky to have a T-1 on your train.

 

@Jones1945,

I found a pencil sharpener in the form of an S-1. Are you jealous now? Cowboy

 

 

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Posted by Overmod on Wednesday, April 29, 2020 5:02 PM

Hermann
Only in Summer 1945, the first derailment took place in Pittsburgh. Then, just one month after delivery of the first serial T1s, 5502 derailed on December 1, 1945, and another serial T1 the very next day. Did somehow, tragically, the two prototypes have the edge over the 5500s in curves?

If I remember correctly, the problem was caused at only one switch location; I dimly and perhaps imperfectly remember it as a double slip switch.  It is possible that the 'problem' was created by track maintenance of some kind, but I think the situation is more likely what Hermann notes.

Thw two original engines had radically different equalization arrangements from the 'production' engines -- for, I think, very good objective reasons.  It's been known since around the turn of the century that equalization of eight-drivered locomotives is better if the equalization is interrupted or 'tied' between the second and third driver pair, with the lead truck equalized with the forward sets and the trailing truck with the rear ones.  This, with some progressive improvement in snubbing and auxiliary springing, is what was done with the production engines right up to 1948.  The original design had a prominent walking beam carrying the equalization from front to rear engine, and this was thought to be causing some of the riding and slip issues -- I have not read the surviving correspondence and source material on this, but it is very clear that substantial changes were made to the arrangement during the war-years testing.

Now, something that is interesting when you look at the T1 spring-rigging arrangements is that a great amount of tinkering went on with the permitted lateral of the driver pairs, sometimes on the order of sixteenths of an inch -- there is a long list of emended numbers, perhaps notable in that by late 1947 there was free lateral on all four driver pairs.  I find it highly suspicious that this would be done on a high-speed locomotive with lateral-motion devices unless it were intended to permit a certain amount of float, at low speed, over the kind of obstacle resulting in derailment in terminal trackage.  (Note that this is very different from the reported issues with T1s losing critical adhesion over frogs and low joints when pulling long consists out of station traffic.)

Now, it would be one thing if Glaze-style stiff lateral compensation on lead and trailing trucks were applied to T1s to keep their required overbalance low (or, in fact, zero, which is a condition likely necessary for T1s to reach the speed their steam generation and valve gear would allow).  That never, apparently, became the case; the assumption seems to have been that the long effective rigid wheelbase and duplex kinetics would keep nosing/hunting minimized.  Interestingly the very large tenders might likely have minimized in-phase surge, too -- so a certain amount of overbalance might have been tolerated that 'shouldn't have been'.  (The effect of increasing augment on propensity to high-speed slip should be no mystery to anyone following along with T1 history!)

There are stories from the Crestline history that describe how much of a penchant 6100 had for derailing (usually somewhere in the driver wheelbase, if I remember correctly) while being run around that servicing point.  To my knowledge that situation was never satisfactorily worked out, even by restricting the engine to particular tracks and stalls.  It would be interesting to examine experiments, if any, with lateral motion on the driver pairs to see what did and didn't help with that.

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Posted by Jones1945 on Thursday, April 30, 2020 11:30 AM

Hermann

@Jones1945,

I found a pencil sharpener in the form of an S-1. Are you jealous now? Cowboy

It depends on the quality of it. Wink Loewy's pencil sharpener:

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Posted by Hermann on Thursday, April 30, 2020 11:43 AM

Jones1945
It depends on the quality of it. Wink Loewy's pencil sharpener:

 

 

OK, you won!

Mine is made in China...

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Posted by Overmod on Thursday, April 30, 2020 3:41 PM

Hermann
OK, you won!

Adding insult to injury -- and perhaps as an awful unintended consequence of the Lionel 3768 Torpedo scam -- item SK-3280 is labeled a "K-4" (yes, Virginia, with the hyphen) on its box and in its description.

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Posted by Deggesty on Thursday, April 30, 2020 3:55 PM

Overmod

 

 
Hermann
OK, you won!

 

Adding insult to injury -- and perhaps as an awful unintended consequence of the Lionel 3768 Torpedo scam -- item SK-3280 is labeled a "K-4" (yes, Virginia, with the hyphen) on its box and in its description.

 

Is that a steam-powered pencil sharpener? Smile

Johnny

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Posted by Overmod on Thursday, April 30, 2020 4:05 PM

Deggesty
Is that a steam-powered pencil sharpener? 

To paraphrase what was said about a different 'plex (Triplex, not duplex) "not enough legs and not enough steam"

But the faithful rendition of the twin stacks makes up for it...

... and we know in principle now how to implement the ditchlights.

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Posted by Flintlock76 on Thursday, April 30, 2020 9:17 PM

Jones1945

 

 
Hermann

@Jones1945,

I found a pencil sharpener in the form of an S-1. Are you jealous now? Cowboy

 

 

It depends on the quality of it. Wink Loewy's pencil sharpener:

 

Jeez, that's some pencil sharpener!

It looks like if you crank the handle a death ray is going to shoot out of the pencil!

I hope anyone who used that thing made sure no-one was standing in front of it!

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Posted by Erik_Mag on Thursday, April 30, 2020 10:39 PM

I would think that pencil sharpener was the inspiration of the ray-guns used in the likes of Flash Gordon and Buck Rogers.

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Posted by Overmod on Friday, May 1, 2020 7:59 AM

Erik_Mag
I would think that pencil sharpener was the inspiration of the ray-guns used in the likes of Flash Gordon and Buck Rogers.

Likely more the other way around -- look at the dates on the strips, and some of the contemporary pulps/covers.  Now, when you get to the Fifties rayguns, there will be more design influence to trace.  

To me the influence is much more obviously from aircraft nacelles and spinners -- turn that support pylon upside-down and it gets much clearer.  

Now, a more interesting question (which I've asked before in a different sort of context) is the influence of the '30s version of rocket ships on the kinds of bullet-nosed steam streamlining -- including the excesses -- we saw in the '30s and that might have proliferated more had there been no WWII and subsequent diesel rage.  (Or perhaps vice versa in some cases?)  Part of this is a topic in design history that might be partly described by 'what does a culture think is 'modern' in design?' -- see for example why everyone saw 'saucers' in the late '40s instead of all the other kinds of likelier planform.  If clumsy torpedoes that circle slowly and blow sparks are the Miracle Ships of the Future, it won't be surprising to see slowly-cycling and spark-emitting locomotives far behind...

(BTW to Hermann and perhaps others:  opportunity is knocking to test your whittling skills.  Just as George Washington got lovely shaped teeth made like piano keys, you can make a sort of 'bridge' to replace the missing part of the S1 'smile' between those funny little wheels.  With a little filing you could gin up correct front and rear sideframe portions, too.  Not that much work, but a dramatic improvement in 'prototypical verisimilitude'... Big Smile)

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Posted by CSSHEGEWISCH on Friday, May 1, 2020 10:25 AM

Diesels were coming anyway, the FT, any number of switchers and various E's all predated WW2.  The war just speeded up the process.  LST's were powered by 567 engines and submarines had OP's for surface running, which was most of the time.

The daily commute is part of everyday life but I get two rides a day out of it. Paul
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Posted by Overmod on Friday, May 1, 2020 4:15 PM

CSSHEGEWISCH
Diesels were coming anyway, the FT, any number of switchers and various E's all predated WW2.  The war just speeded up the process.  LST's were powered by 567 engines and submarines had OP's for surface running, which was most of the time.

But it's also true that, as Baldwin pointed out in 1940, the actual return on equity of a 6000-horsepower locomotive's worth of FTs, given the enormous capital cost over modern steam, might be better for steam given the large sunk cost of support for the existing steam locomotives.  

We might have gotten to 'dieselization' without the combination of factors in the late '40s ... but it would likely have followed the path nearly everyone expected in the mid-Forties: gradual replacement of serviceable steam power as it wore out, with replacement of a 'class' being accelerated when its net 'contribution to profitability net of depreciation, deductions, tax rebuildability, etc. became negative.  What wasn't expected was that the overhead costs for any steam, no matter how modern, would balloon for so many roads as they did.

What else was not likely expected was that many banks were more willing to loan or trust the high purchase price for diesels, knowing from a banker's perspective that the locomotives were 'fungible' with little more than a new coat of paint.  And if the banks weren't fully willing, GM might have plans that would help...

I periodically speculate on what would have happened if Baldwin had had the combination of chance and financial savvy that GM-EMD did regarding 'bringing down the cost' of the Essl modular locomotive, which was the only thing really competitive with a good modern eight-coupled main line locomotive up to the war years.  Instead they looked at the numbers and went with EMD-style carbodies on bogie trucks... with slow-turning runs-forever tugboat derived engines of strictly limited horsepower-to-weight in them.  And waited for the free-piston turbine revolution ... that, when it came, didn't even completely come to GM-EMD.

It is true that Dilworth's vision for building-blocks-of-'units' MUed power was really better than anything that could have been developed with similar combination of capability and reliability in steam.  By the end of the war this had essentially obsoleted high-pressure flash steam; by the end of the '40s it would essentially obsolete all but the most sophisticated turbines ... and in improved second-generation form would prove the kiss of death, had there not been others 'first', to even the most carefully promoted steam power.

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Posted by Hermann on Saturday, May 2, 2020 2:37 AM

Overmod
(BTW to Hermann and perhaps others: opportunity is knocking to test your whittling skills. Just as George Washington got lovely shaped teeth made like piano keys, you can make a sort of 'bridge' to replace the missing part of the S1 'smile' between those funny little wheels. With a little filing you could gin up correct front and rear sideframe portions, too. Not that much work, but a dramatic improvement in 'prototypical verisimilitude'... Big Smile)

As I am a model maker, I actually could do that:

"A small step for my CNC mill, one giant leap for a Chinese pencil sharpener"....Whistling

 

But as to your thoughts about the financing of diesel power: what if in the 1940's the banks were more eager to give money for diesels because they saw a chance of the diesel having not the longevity of steam, thus needing to be replaced sooner, meaning the RR officials needed to visit the bank offices more frequently for more loans?

 

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Posted by Hermann on Saturday, May 2, 2020 3:44 AM

Overmod
(BTW to Hermann and perhaps others: opportunity is knocking to test your whittling skills. Just as George Washington got lovely shaped teeth made like piano keys, you can make a sort of 'bridge' to replace the missing part of the S1 'smile' between those funny little wheels. With a little filing you could gin up correct front and rear sideframe portions, too. Not that much work, but a dramatic improvement in 'prototypical verisimilitude'... Big Smile)

As I am a model maker, I actually could do that:

"A small step for my CNC mill, one giant leap for a Chinese pencil sharpener"....Whistling

 

But as to your thoughts about the financing of diesel power: what if in the 1940's the banks were more eager to give money for diesels because they saw a chance of the diesel having not the longevity of steam, thus needing to be replaced sooner, meaning the RR officials needed to visit the bank offices more frequently for more loans?

 

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Posted by Overmod on Saturday, May 2, 2020 9:51 AM

I'm stil waiting for someone to find and post the actual wording of the communication by Symes (ideally in the context of an exchange of communications) regarding specific use of the S1 in 'freight' service.  

Among other things, such a decision -- on an engine which by that time probably had north of 3 million gold dollars of PRR money in it -- implies the service reliability on block-mail or M&E trains was no better than on passenger service.  And that high-speed slipping was more of a problem even at 'typical mail' speeds than explicitly reported and recorded... 

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Posted by Jones1945 on Tuesday, May 5, 2020 8:31 AM

Overmod

I'm stil waiting for someone to find and post the actual wording of the communication by Symes (ideally in the context of an exchange of communications) regarding specific use of the S1 in 'freight' service.  

Among other things, such a decision -- on an engine which by that time probably had north of 3 million gold dollars of PRR money in it -- implies the service reliability on block-mail or M&E trains was no better than on passenger service.  And that high-speed slipping was more of a problem even at 'typical mail' speeds than explicitly reported and recorded... 

 

I am also waiting for it. Syme's thought, mainly complaints, on the S1 is mentioned in the article "The S1 - Biggest of them all" by Charlie Meyer but he didn't quote Syme's actual wording. If I were in his position I would have complained too. I wonder if he would have complained even more (for mechanical failure caused by overspeed) if PRR picked N&W Class J instead of T1, since the Class J wasn't designed for 100mph daily operation even though the Js could hit 110mph or above in test runs. 

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Posted by Overmod on Tuesday, May 5, 2020 7:00 PM

Jones1945
I wonder if he would have complained even more (for mechanical failure caused by overspeed) if PRR picked N&W Class J instead of T1, since the Class J wasn't designed for 100mph daily operation even though the Js could hit 110mph or above in test runs.

The issue with the 70" wheels on passenger power is carefully described in the 'official' PRR report of the J testing.  

Part of the problem is that we're talking people who reached their positions of great responsibility having learned conventional wisdom about balancing, diameter speed, etc., and who may have been influenced negatively by the 'experts' in modern scientistic balancing coming such a cropper with the ACL R1s.

Even the Q1, which would have tremendously benefited from 72" wheels with disc centers and lightweight rods, "conventional" augment reduced by the duplex principle, was given what was tantamount to LV dual-service 4-8-4 driver diameter ... splendid, but excessively heroic for an "improved M1".  

Now, just exactly what PRR thought would be a 'proper' high wheel for a dual-service 4-8-4 is a bit confused by perceived passenger-engine requirements: probably the 'sweet spot' is in the 74" to 75" range with modern balancing ... but we then have the example of Kiefer's 4-8-4, which was wasted with its sisters' 75" but magical at the moral equivalent of 80", so I think it is safe to assume that any contemporary 4-8-4 would be considered the "doubleheaded K4 replacement" just as the T1 would be ... and would be expected to have the 'high wheels' dictated by motive-power-department choice.  Regardless of whether Virginia intelligence and magic gave well-over-100mph capability to a locomotive with M1-size drivers, and a great deal of 'normal PRR passenger-train' running flexibility to boot...

One thing I have to wonder, though, is what the effect of Glaze balancing on the Pennsylvania Js would have been.  A postwar change on a great many of them was to increase driver diameter to 70" -- done expediently with fatter driver tires, I suspect... but it need not have been that.  If we use lightweight inboard rods, crosshead, and pistons, we can reduce the operative overbalance in the main to something around 120lb (see what the peak vertical component of rod thrust at 'best speed' cutoff is, and use it) with the rest in the coupled wheels -- and this in turn reduces the need for a cast driver-center type that accommodates heavy angled weights.  Then reduce the overbalance to what the lead and trailing trucks and longer driver wheelbase can 'stand' -- and you might get a surprisingly long way toward the J's tolerable maximum speed at acceptable vertical augment.  All without compromising your desire for 125mph rayguns on wheels for the marvelous resumption of passenger traffic after the war...

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Posted by Hermann on Saturday, July 4, 2020 4:50 PM

Overmod

It is possible to model the S1 in software and do multiphysics and kinematic analysis on the chassis to determine its stability and freedom from resonant couples (as was done, for example, for the German 05 class which had a calculated severe emergent critical speed close to 122mph, perhaps explaining why a run to outdo Mallard was never made).

 

The run on May 11,1936 was made as a demonstration to impress the government to invest in high-speed trains. It is proven that the emperor of that time was not interested in railroads at all, instead he preferred the Autobahn and the Volkswagen. Surpassing the 200 kph mark was just for public relation.

 

The Mallard run was in 1938, when orders were given by the Reichsbahn for 400 streamlined pacifics with slightly smaller dimensions than the class 05 prototypes classes 01.10 and 03.10.

The first of the serial streamlined steamers was delivered on a tuesday. Thursday the same week, September 1st 1939,  the Volksempfaengers spread the news that from 5.45 "there will be shot back". Time for high-speed steam in Germany was over. Most of the streamline locomotive orders were cancelled and the Reichsbahn had neither interest nor time to improve the speed record, of which the 05 with its superior dimensions was surely capable of.

 

Happy 4th of July!

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Posted by Overmod on Sunday, July 5, 2020 11:22 PM

I have tried hard to appreciate the 03-10 and 01-10 [note correction; see discussion below ... it comes of trusting Germans on German locomotive-classification syntax Embarrassed] classes, particularly the latter, but I've never thought of either as anything comparable to a class 05 for high speed.  It was my somewhat naive assumption that roller rods plus three-cylinder drive were all that would be needed to match Mallard's speed on smaller drivers -- did any of the 01-10s in fact come anywhere near that speed range?

Now with ten of them preserved, it is something of a temptation to give one a comprehensive American high-speed balancing plus opening up of steam circuits, compression control, modern front end, etc. and see what the design could do.

I notice 01-10 1104 is in something of the straits the C&O 2-6-6-2 finds itself in, and with donations down due to the coronavirus; perhaps we should put out the call here and on RyPN to donate to the effort.  This would be a fun engine to return to high-speed-capable excursion service.

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Posted by Hermann on Monday, July 6, 2020 2:27 PM

As you know, the Germans were quite unwilling to surpass the 400rpm rotational speed, which is about 150kph / 93 mph with 2000mm drivers. (Compare this to a J going westward to Chicago....). The last batch of the 01.10 had been equipped with roller-bearings, but there was simply no experience with light-weight alloys  that time (at least not with locomotives...). The standards for most locomotive parts, as they had to be exchangeable, were set in the 1920s, and the chief mechanical engineer of the DRG was quite conservative to say the least...

These streamlined pacifics were given a top speed of 150kph. After the war, when the streamlining - or what was left of it - had been removed, this was reduced to 140 kph. When 01 1102 was returned to life, it received just minor improvements, as a full boiler insulation due to concerns the blue color might suffer from the boiler heat in the long term.

After 01 1102 was re-streamlined, it was test-run and achieved 160 kph/99mph on February 9, 1996, so becoming the fastet 01.10 ever.

Surely, it would be the ideal candidate for Porta-or Wardale-style improvements, yet it depends on the owner, his financial capacities and his will. Luckily, there are no speed restrictions for steam here, but the track infrastructure has been cut back badly. Hardly any sidings to be found on many lines. You can run steam on the DB, but as you need slots between the scheduled DB trains, the faster the engine, the better! The usual steam specials are powered with locomotives going at least 80 kph/50 mph.  The right place for the T1 is here...;-).

When we saw old 1309 in Baltimore the first time in 2012, no one then believed its fate might turn out as it did, but no matter how long this restoration might take - theft, lacking of funds plus the curve/turntable issues - 1309 is going to be a winner soon. For 01 1102 things look rather bleak, it will most probably remain cold. Heavy overhauls cost in the range of half a million here, and then you have six years only to go.

Roger Waller surely would know what to do if he had his hands on it. Wider steam passages, slightly higher boiler pressure, even better insulation of course (cylinders included), new blast pipes, may be even compounding.. probably poppet valves might be a "nice to have" too, of course Franklin B..

The one advantage 01.10/03.10 and 05s surely had over the PRR streamliners was a casing which had been tested before in a wind-tunnel. What they didn't have was the looks of a T1...

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Posted by Juniatha on Thursday, January 14, 2021 3:37 AM

(double posting - sorry)

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Posted by Juniatha on Thursday, January 14, 2021 3:43 AM

Arnold Haas - well, yes, uhm ...

 

He also wrote a Niagara would accelerate faster from 80 to 100 mph than from 60 to 80 - which would only be possible if the mean tractive effort would be larger in the higher speeds - which by itself is virtually impossible. 

The Niagaras had comparatively very small cylinder volume for given boiler pressure (in relation to both their adhesion mass and their steaming capacity, that's why their highest indicated output was only reached around 75mph at 52% cut off - a very inefficient, long c/o. I think Paul Kiefer didn't want to take risks on too high a piston force and / or to long a piston travel. With a cylinder volume half ways more to the example set by the N&W J class the Niagara's ihp could have surpassed the 7000-mark easily and on the same coal consumption ... however maybe Paul Kiefer was wise not to overdo things - today substantially larger piston forces would be no problem with superior materials.

All those questions of 'how fast did she go' and 'how fast did she really go at maximum' and 'if we allow the engine to throw rods way ahead in the event - what speed at maximax could at-all ever have been reached for just a moment' are fine and exiting to those who do not take a closer look at what it takes beyond boiler power and ability of cylinders to operate the filling and exhausting in a half ways civilized manner - as is when the valve gear will work orderly and keep together by that. Mind that with a 20% over-revving, forces reach 144% of the design maximum. Who will tell me it can stand that for any longer than a few minutes?

If we take instead a look at the permanent road bed then we must ask where in hell should an engine have even reached such speeds before outrightly derailing? Name me the 1930s 1940s track if you can? I bet you there was none - not with the universal simple nailed rails and that sloppy joined rails and that minimum of 'dirt' embankment.

Some years ago I saw an advertising film by the Pennsylvania, it was to show how soft, caring and smooth the passengers travel on the PRR high speed mainline track. Now, I must say, they were being bounced around quite a bit and swayed sideways - and at what speed? watching the outside trees and houses go by it was some 80, 85 - at best! All in all it was more like on the - sorry - PKP, the Polish state railway when in the 1990s they had been cought by the fresh wind of change and had put on some speed, rising from 100 km/h mostly to more 120 km/h stretches, just like that, track upgrading only following year by year.  That said, I had also witnessed an upgraded electric line travelling from Bydgosz to Warzawa: that was 100 mph on all-welded, straight and billard table level track, the neighboring rails were dashing by without showing any flares or buckles in the flow. Had the Pennsy had this sort of track I would consider 110 - 120 mph for some T1 rides - but still not like 'more often than not' or as last run of a worn down neglected engine! Let's ignore a number of points standing against these high speed claims and look just at the fact that over-revving would have soon worn down the cam surfaces if no more of the poppet valve gear. Now, it should be self-understood that from an engine no more having any precise - and even! - timings for steam exchange you cannot expect any extraordinary performance and speed because the erractic valve events cannot help but counterblock working quality of the engine. As long as things haven't gone too far, there is an interesting balancing happening: since the steam wasted is adding to the intensity of draughting the boiler can likely come up with the extra amount of steam asked - however what's wasted gets fully lost to cylinder performance - i e although the engine makes an extra amout of steam it gets weaker in cylinder power - and this very soon leads to it's failing to live up to demands, less so can it be extended to produce an extra amount of power output. Since wind resistance goes up by the square of speed increase and running resistance also tends to increase because it becomes less acurate, involves more flange /  rail contact and generally more abortive movements of the train consist, we can roughly assume the extra power demanded to pull an existing train not at 100 but at 120 mph is about 40% larger. Where is this extra output supposed to come from? 6500 ihp - when 100% in good shape! does not make me all too optimistic for such a reserve! 

Also, I must say, for any such very high surpassing of regular speed limits, the engines all lacked drive wheel diameter. At some 2 metres (79") riding diameter and 200 km/h (125 mph) the rotational speed is 531 rpm - very, very high for any steam locomotive, let alone two cylinder engines. That was the only plus side of the PRR Duplex engines S1 and T1: they had four - the #6100 had a 7% larger riding wheel diameter - but for her capacity of boiler and four piston valves which were for once not cramped between distance of cylinder covers but had (a minimum of) proper exhaust chambers and more straight inner steam passages this was still clearly on the small side for any attempts to go 120 mph and better. 90 ins would have been nearer to it - myself, when I had put up a free design of a 6-4-4-6 engine with an 8-8 tender I gave her 100 ins wheels to run 140 mph regularly - with full equipment of roller bearings on axles and light weight rods - but with Walschaerts / piston valves on outside cylinders, if of ample steam passage cross sections since this still means 470 rpm - still very fast for a steam locomotive - more so for a very large and powerful one! No, she doesn't have four cylinders, nope, not six neither - but two times four cylinder compound engines with the HP outsides. That means the engines are self-balanced and I don't have interference of disturbing reciprocating actions nor any loss of adhesion with increase of speed above that which is due to the more vivid action of the wheels on rails (even with a smooth running locomotive where the drive sets are being protected by each the 6 wheel bogie and delta truck).

In the article by Arnold Haas that appeared in the German Lok Magazin #49 about 1971 he claimed that super fast run in 1949 - in other words when the engine if it had still existed at all, had been on the scrap track for years. If the engine drawn back out from there, just set to steam and put right on the line to make up a large lateness by going 'a little faster' this day would have come up with 140 mph - then it becomes fully inexplicable why she should have been put back there and scrapped - in other words as an American Hero, there is nothing to be expected! Or what?

Well, I believe someone just didn't like that plain Loewy 'farmer daughter's dress' drawn over the front - but it wasn't me folks, I wasn't even born for another 27 years ..

Juniatha

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Posted by Juniatha on Thursday, January 14, 2021 5:05 AM

daveklepper
Or is it possible that the track was not as well maintained?

daveklepper
Or is it possible that the track was not as well maintained?

==> YES <==

J

  • Member since
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Posted by Juniatha on Thursday, January 14, 2021 7:13 AM

1.10 ?

????????????????????????

Ooooohhhh! I seeeeeeeeeeee-he-he-he - geeeeee!

You mean 01-10! (speak oh-one-ten, or after 1968: oh-twelve for 012)

Well, you don't know about the numbering system of the Reichsbahn / Bundesbahn - ok:

Express locomotives of the standard types (1925 / 1950) are numbered as classes 01 to 10. Mind the 'O'! Because these series designations are *always* two digit.

Then there is a free space, then the individual number of the engine within this class - started with three digits 001 to 999, it became obvious later on that this didn't suffice, so larger numbers of freight locomotives, mainly got four digits from # 1000 upwards. This meant there was a 44 290 and a 44 1290 or a 50 078 and a 50 778 and a 50 1778, for example. On the number plate, which shows class - two digits - plus individual locomotive number - three to four digits - there is no point, dot or spot. There is just the space as between two words. Note that in this classification the first locomotive is 001 (not 000 or rather xx00 as in the USA)

Now, it turned out that there were certain loco classes they didn't want to give a new number as they were rather seen as further development of the original class, they were given a new, as yet free (not used) block of hundreds or thousands for counting the individual engines. In quoting the new class 'variation' the first digit of the hundreds / the first and second digit of the thousands is noted as an index (high) - or simplified as a normal digit behind a dot (not a point, less so a sign of fraction)

As for instance class 01, heavy standard Pacific:

Original engines 01 001 to 01 231; added the rebuilt 10 class 02 four cylinder Pacifics as 01 232 to 241 - all these were class 01 engines

1960s substantially rebuilt DR 01s became engines

01 501 to 535 - they were 01.5 engines

The three cylinder variation of the 01 were numbered 01 1001 and 1052 - 1104 they were thus class 01.10 in short.

Since of the 44 class three cylinder Decapods almost two thousand were built there were numbers 44 001 to 010 prototypes (service tested against the two cylinder 43 001 - 010; then two 25 bar four cylinder compound engines were realized as part of another large scale test; then with # 013 to 065 came the intermediate design and from 066 to over 2000 came the final design. Since after 1945 all the earlier engines were no longer in service it remained simply the 44 class. When the Reichsbahn, DDR, rebuilt some engines with new welded boilers as replacement for worn orginals, there was no special series number given. However when DB renumbered all their engines, the oil-fired 44s became new class 043 (the original 43 was not in service on DB); when DR also did their renmbering the oil-44s became new 44.0 and the remaining coal fired engines of the class became 44.10 for 1001 or higher - some engines in each case had to be renumbered to fit to the new system. 

The 52 class light Decapod brought the old system to its limits because of the original engines already some 7800 had been built (it is not exactly known how many to the engine had all in all been built since after 1945 several re-established railways had more engines built, so in France (at Gafenstaden), Belgium (Tubize) Denmark, Norway, Austria (Wien Floridsdorf) Poland (Crzanow - speak Chshanoh), Tchecoslovakia (Skoda, CKD), Yugoslavia (rebilding only), Bulgaria, Roumania (Resita) - on the other hand Russia had confiscated 52s by the thousands, known under the nickname simply 'the Woman' or 'the German Woman' she got highly popular with the Russian railroaders - well as a woman I could think of better .. but as a locomotive, that's probably something different). So the various railways in Europe for some time after '45 had some sorting out to do to get their 52s all properly numbered and put in service. In Austria there was the mysterious case of one 52 suddenly on the site and nobody knew how she had come there, all it looked like by the 33 class given she had come back up from Yugoslavia; in order to be sure to avoid doubling numbers they assigned her the quasi 'artificial' number 52 8000 - and when some Yugo railroaders appered then asking for 'their' 33 class locomotive the Austrians just said "No such locomotive here!"

But it didn't end there: in the 1960s the DR in DDR (Eastern Germany) decided not only to upgrade a number of 52s to full standard equipment but also to rebuild 200 engines with new combustion chamber boilers and re-number them class 52.80 - intriguingly thereby forcasting the decade when regular steam service would end on DR. One such engine - 52 8055 - was tested in Switzerland in the 1990s prior to rebuilding and developed some 700 ihp above the original - due to the superior steaming of the 1960s boiler when fired with good quality coal.

Yet this was still not the end since DR, always looking to fire brown coal or soft coal, rebuilt a number of locomotives into coal-dust burners and classsify them as 52.90 that were known to be very dusty indeed and crews always tried to avoid them. But the Wendler system worked well and saved DR a number of expensive coal imports.

No 52 was ever professionally rebuilt to oilfiring - if we don't count the rather makeshift arrangements by the Russian railways on individual engines and the lone 52 8055 that got diesel-oil firing in Winterthur, got rebuilt and rather heftily fouled up beyond recognition. Well, that showed how lucky the design and appearance of the 52 class really was - although from the start no one had - officially - been charged with the task of tuning this into a good looking locomotive and if you may look at Mr Degenkolb as her 'father' (design supervisor) he was a strictly logic and down to facts engineer, even rude in some ways and certainly no artist with a fine hand.

And yet ...

Juniatha

  • Member since
    September 2003
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Posted by Overmod on Thursday, January 14, 2021 10:33 AM

Juniatha
[Haas] also wrote a Niagara would accelerate faster from 80 to 100 mph than from 60 to 80 - which would only be possible if the mean tractive effort would be larger in the higher speeds - which by itself is virtually impossible.

 

This is not necessarily complete tripe; it is possible that, using the 'reservoir' of supercritical water and excess available superheat at high draft level, there would be 'enough steam' to produce the necessary acceleration.  Not particularly cost-effectively, and with no guarantee that the locomotive would hold speed (or continue acceleration) beyond a few seconds or minutes, but the higher cyclic does translate into greater cylinder horsepower up to the point that the valves and gear cannot cleanly admit and release the steam ... and assuming the running gear can transmit the thrust without problem, which I think is quite a different matter...

Do I really think that acceleration all the way from "80 to 100" would be faster than "60 to 80"?  Not really... but I'd want to see proof before calling him even more of a fibber... Wink

The Niagaras had comparatively very small cylinder volume for given boiler pressure (in relation to both their adhesion mass and their steaming capacity, that's why their highest indicated output was only reached around 75mph at 52% cut off - a very inefficient, long c/o. I think Paul Kiefer didn't want to take risks on too high a piston force and / or to long a piston travel.[/quote]

IIRC that Kiefer originally specified 290psi for this design, and to be honest I would think the old story about the Super Hudson design providing too much 'thrust or kick' and bending rods would be far more applicable to the Niagara.  It might be interesting to run comparative numbers for the Niagaras at original vs. stepped-down pressure to assess what the 'right' cylinder dimensions for 265psi would have been.

With a cylinder volume half ways more to the example set by the N&W J class the Niagara's ihp could have surpassed the 7000-mark easily and on the same coal consumption ... however maybe Paul Kiefer was wise not to overdo things - today substantially larger piston forces would be no problem with superior materials.[/quote]

eBut the issues with Niagaras did not involve "greater peak horsepower" -- the water-rate considerations even on a railroad with frequent track pans would have become significant with the advent of proper water treatment for modern boiler steels -- and in fact if you look at the assumptions behind the detail design of the NYC 5550 (and inherently in the April '45 spec for the C1a) you will see this very clearly.  Reading between the lines, I suspect there were the same kinds of failure that N&W was seeing with the extended #4 driver-pair pins on the original lightweight J rods; the Niagara design was somewhat more susceptible to priming even with the careful steam-separation design, and the result on the very lightweight Timken construction could be dramatic.  

All those questions of 'how fast did she go' and 'how fast did she really go at maximum' and 'if we allow the engine to throw rods way ahead in the event - what speed at maximax could at-all ever have been reached for just a moment' are fine and exiting to those who do not take a closer look at what it takes beyond boiler power and ability of cylinders to operate the filling and exhausting in a half ways civilized manner - as is when the valve gear will work orderly and keep together by that.

eN&W and PRR, of course, found a point of failure that came up 'quicker' than valve-gear problems: insufficient valve lubrication (or dimensional clearances) at superheat and machinery speeds in excess of 'design'.  While some N&W valve-gear was notorious for, 'unraveling' at times, as Ed King memorably put it, that was not a factor in the infamous test failure on PRR either by the noted results or later discussion of the testing by Cover et al. as preserved at the Hagley.

Mind that with a 20% over-revving, forces reach 144% of the design maximum. Who will tell me it can stand that for any longer than a few minutes?

Especially if Chapelon was correct in his assessment of 'routine' lateral bending in the Timken narrow-section lightweight rods.  

Of course, that presumes the engine can actually be over-revved continuously, rather than (as was clear to me) repeatedly high-speed slipped without proper notice -- as in the case of the "130mph and higher" operation reported by 'Franklin engineers' to Vernon Smith in the '40s.  The combination of inertial and shock forces on lightweight rods in high-speed slipping is, if anything, far higher in the deleterious senses than steady-state high speed would be, and probably makes your point even more compelling.

If we take instead a look at the permanent road bed then we must ask where in hell should an engine have even reached such speeds before outrightly derailing? Name me the 1930s 1940s track if you can? I bet you there was none - not with the universal simple nailed rails and that sloppy joined rails and that minimum of 'dirt' embankment.[/quote]

eYou're leaving out the enormous amount of maintenance that was used by railroads like the Pennsylvania or NYC to keep a jointed-rail mainline in proper shape.  Something similar was involved on railroads like C&NW and Milwaukee in the early Thirties to get a railroad of almost primitive civil construction by modern standards to take 100mph operation with motor trains and then with steam locomotives.  There are plenty of references on how to do this that refute a cavalier description involving 'nailed' rails and 'dirt embankment'.  NYC as late as 1966 was able to observe 183mph running nearly-unmodified RDC trucks on what I recall to be jointed rail -- that in itself is not a pure reason to discredit a certain amount of high-speed operation, at least one-time or for 'special' purposes.  

There is no question however that better use of LWR and proper fixation systems would be appropriate, if not necessary, for any sustained running with reciprocating steam much above the ~100mph maximum practically achieved through the end of 'commercial' large high-speed steam operation in the United States.  And that even at the peak of the section-gang era on PRR, the absolute track quality was any better than would permit "safe" operation at indicated track speed -- as you note, 80 to 85 max.

Now, on the other hand, there are some interesting things that come up with regard to actual track integrity.  In addition to the Haas argument, which I believe was supposed to have been reported in the German literature as 1947, conveniently just ahead of the ICC order (which didn't take effect until 1950, but that point might be lost on someone not familiar with US government practice), there was a story in the magazine Popular Mechanics in which someone supposedly involved with running 6100 claimed she had run 138mph.  We could have fun discussing the various mechanical details that might or might not have allowed such operation ... but instead, look at the Google Earth or historic-aerials view of the particular location where the PM 'feat' was supposed to occur.  This goes right through the middle of a town with streets and buildings closely encroaching on the right-of-way, and directly to the west of town there is a railroad crossing at grade.  Personally I can't imagine operating a reciprocating locomotive at high speed across jointed diamonds and untuned paved grade crossings, even with a proper modern suspension...

And then there are the suspension and riding characteristics of the actual consists PRR would have run behind a locomotive at such a speed.  There are a number of reports -- whether anecdotal or 'doctored' I can't say, but I find them probable -- that the great majority of contemporary PRR equipment was encountering considerable, shall we say, nonlinear suspension and guiding behavior at speeds as low as 110 to 115mph; one of these stories claims the ride on a T1 was considerably better than in 'the business cars behind' which remains to be properly established with replica 5550 modeling and testing, but as far as the rolling stock goes is, I think, capable of establishment with far less rigorous proof.  

The idea that "142 and a fraction" mph is just a smidge higher than "138" is even more amusing, although to the kind of people who think automotive practice -- like 120mph speedometers -- characterizes railroad design, it might seem less unlikely.

Some years ago I saw an advertising film by the Pennsylvania, it was to show how soft, caring and smooth the passengers travel on the PRR high speed mainline track. Now, I must say, they were being bounced around quite a bit and swayed sideways - and at what speed? watching the outside trees and houses go by it was some 80, 85 - at best! All in all it was more like on the - sorry - PKP, the Polish state railway when in the 1990s they had been cought by the fresh wind of change and had put on some speed, rising from 100 km/h mostly to more 120 km/h stretches, just like that, track upgrading only following year by year.  That said, I had also witnessed an upgraded electric line travelling from Bydgosz to Warzawa: that was 100 mph on all-welded, straight and billard table level track, the neighboring rails were dashing by without showing any flares or buckles in the flow. Had the Pennsy had this sort of track I would consider 110 - 120 mph for some T1 rides - but still not like 'more often than not' or as last run of a worn down neglected engine![/quote]

A great deal of PRR practice fell apart very quickly during (and after) WWII -- see if you can find the postwar ad that goes into their track-structure cross-section and essentially whines that the Government needs to help them rebuild after their colossal effort to help win the war... etc.  In any case my personal, and essentially unjustified, opinion is that PRR made a great more out of high speed running than their actual plant ever really permitted except in a few, fundamentally virtually unimportant, sections.  Some of the discussions of doubleheaded K4s up against their practical speed limit (of about 92mph) mention the most alarming loss of compliance or guiding integrity on curves -- without discussion of what that kind of shock might do very quickly to jointed or spiked rail or track geometry.  But I was not there to complain.

Let's ignore a number of points standing against these high speed claims and look just at the fact that over-revving would have soon worn down the cam surfaces if no more of the poppet valve gear.[/quote]

eThis is not a major factor for the PRR T1, at any rate, which used an OC gear with lower travel at shorter cutoff, and valves with comparatively low inertia.  Even the crude increase in spring pressure to debounce the valves would not have radically increased cam-lobe wear as the springs were progressively wound and lobe engagement would not have been under high pressure (i.e. not desmodromic) close to valve cutoff.  The cam-lobe wear in the original laterally-shifting design of the late Forties was more associated with line contact at 'common' settings between the complex contour and the spherical followers -- but this was less a 'performance' issue than a flexibility-in-service one.  (We could argue whether modern materials and surfacing techniques can partly or wholly overcome some of these issues -- but other considerations are I think much more significant)

Interestingly, the problems with the T1 maintenance do not appear to have been either in the 'inconveniently-located' gearboxes or in the actual oscillating-cam and follower mechanism, but in the little valve gear pieces that (erroneously, in my opinion) control the motion.  SHM makes sense to drive long-lap, long-travel valves, but simply doesn't apply to the 'proper' motion of poppet valves admitting steam.  

It is my uncharitable assessment that there was more than a little 'tomfoolery' in Kirchhof et al's claims for the original Franklin System as being something that could be effectively driven in conversion by conventional valve gear ... but some of that remains to be established in actual modeling and testing.

At this point the discussion becomes highly interesting in a number of significant effects -- but I have to go attend to other business.  I'll take up some of the other points in a few hours, God willing.

 

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