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

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Posted by M636C on Monday, January 18, 2021 6:41 PM

I think it is fairly clear that the Spanish invasion plan left a lot to be desired, and was not carried out well.

I was looking at the text of Sir Henry Newbolt's poem, used in the song I posted earlier....

Drake he's in his hammock till the great Armadas come,
(Capten, art tha sleepin' there below?)
Slung atween the round shot, listenin' for the drum,
An' dreamin arl the time o' Plymouth Hoe.
Call him on the deep sea, call him up the Sound,
Call him when ye sail to meet the foe;
Where the old trade's plyin' an' the old flag flyin'
They shall find him ware an' wakin', as they found him long ago!

The second last line, which I've marked in bold, struck a chord.

A magazine for the RAN Submarine community is called The Trade...

For the fight with the Armada in 1588, Effingham, Hawkins and Drake brought their own ships as they were all privateers, twelve ships in all.

I suspect that the trade was piracy.....

Peter

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Posted by Flintlock76 on Monday, January 18, 2021 7:40 PM

M636C
I suspect that the trade was piracy.....

Shhhhhhsh....  

They preferred the term "corsairs."  More respectable you know!  Wink

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Posted by M636C on Tuesday, January 19, 2021 2:52 AM

Juniatha

Hello Peter

Now this *is* a contribution - I didn't know of that project.

Thank you!

Juniatha

 

There is another from the Riddles, Cox and Bond period....

http://www.82045.org.uk/

Peter

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Posted by Juniatha on Sunday, February 28, 2021 11:07 PM

Gary

at this time I cannot post a proper answer because I cannot post any picture / drawing / diagram - which I would need to lay out some connections between amount of steam / cylinder volume and the consequences on cylinder efficiency due to limits of valve gear. I wanted to post an indicated hp curve over speed which is essential to see the difference various cylinder volumes would make and the influence of more or less capable valve gear and cylinder steam passages.

Sorry for that. Maybe it will straighten out and I can then post the matter.

Ciao

Juniatha

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Posted by Jones1945 on Saturday, March 27, 2021 4:50 AM

Two color photos of the PRR S2 from the internet, both equipped with the B&M style smoke deflectors:

 

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Posted by Flintlock76 on Saturday, March 27, 2021 8:33 AM

Jeez, I never noticed it had smoke deflectors.

Thanks Mr. Jones!  I learned something today!

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Posted by Overmod on Saturday, March 27, 2021 9:41 AM

The S2 had not one, but two distinct styles of deflector, showing some of the history of deflector "effectiveness" in North American practice.

The small deflector system pictured (reminiscent of the system applied to B&M Berkshires) was only in use a short time; it was replaced by the more familiar 'Niagara-style' elephant ears by 1947.

Something you may not have noticed is that the B&M ears were not the only smoke/steam-lifting devices -- look for the deflector plate in front of the steam dome, which is visible in the top shot but not the second.  A clearer view of it is here:

https://web4.hobbylinc.com/gr/bro/bro2695.jpg

I note that in the picture Jones1945 provided it appears that the plate is already showing some deterioration or damage (see the crack of daylight?) and there may be discussion of this in the surviving material at the Hagley, as 'optimizing the design' of this locomotive was still a priority at PRR for the duration of the 'early' deflector installation.

That the elephant-ear design worked for locomotives of this size and speed might be taken from their fitting to Niagaras, FEF-3s and the 6200 without, to my knowledge, removal once installed.  On the original Niagara these had a vertical 'trailing edge' but the productuon engines had the angle; interestingly the "other" late Kiefer design, for the A-2-A Berkshire, showed these in the diagram before the locomotives were constructed.

 

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Posted by Jones1945 on Monday, March 29, 2021 12:11 AM

Flintlock76

Jeez, I never noticed it had smoke deflectors.

Thanks Mr. Jones!  I learned something today! 

You are welcome, Wayne. It was probably because Lionel's PRR S2 models never had smoke deflectors equipped. If you are not a Pennsy fan you probably didn't notice that.

I found the B&M style smoke deflectors looked very attractive on the S2. For the sake of aesthetic, PRR did a great job making the smoke deflectors as small as possible which fit the handsome front end of the S2. Too bad that it wasn't good enough to lift the smoke and lasted less than 2 years.

 Here you can see the deflector plate in front of the steam dome that was mentioned by Overmod in the previous post.

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Posted by Flintlock76 on Monday, March 29, 2021 8:33 AM

That's a nice model!  Really high-grade!

The S2 I've got is the old Lionel 681 from the '50s, which needless to say doesn't have that kind of detail.  It's a very good runner though, solid and reliable even after 70 years!

I wasn't even planning on buying one myself but I was in Henning's Trains in Lansdale PA several years ago and there it was at a price too good to pass up. 

The funny thing is the S2 worked out a lot better for Lionel than it ever did for the Pennsy! 

Here's the 681.

http://www.tandem-associates.com/lionel/lionel_trains_681_loco.htm  

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Posted by Overmod on Monday, March 29, 2021 10:32 AM

While we are on the subject of the S2, we might look at some of the practical details of its successor, which Westinghouse was still touting well into 1948.

As I have said, implementing a practical multispeed transmission and eliminating the ridiculous reverse turbine were priorities, and it is not surprising to see patents (filed, in fact, the same day) which quite correctly demonstrate a two-speed planetary transmission and robust geared reverse (2435633A and 2469573A), together with an alternative by a different engineer (2447136A) that provides reversing via the planetary.  Newton filed an improvement on the gearing arrangement a month later (July 1946).

Unfortunately the actual patents did not start to issue until early 1948, by which time both the societal factors and railroad 'exigencies' that led to the first great wave of dieselization were becoming well recognized.  There was little place for large, relatively advanced steam power to be built new; what interest there was in turbines became directed first to different types of mechanical drive not involving rods and then, famously and unsuccessfully, into electric drive to all wheels...

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Posted by Sara T on Tuesday, March 30, 2021 4:50 AM

Overmod, you wrote: >>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).  There are some details that would need to be addressed to make the locomotive properly stable on contemporary PRR track west of Crestline, particularly the lateral on the lead truck and on the first driver pair; to my knowledge, this received nothing like the attention the T1s did in the period between 1946 and 1948.<<

I'm sorry but this is all wrong. There never was such a problem. 122 mph are 196.3 km/h. The fact alone 05002 ran a longer stretch at or over 196 km/h with a top of 200.4 km/h is prove enough this is wrong. This can be seen today in the measurement graph of the run. Grunewald locomotive testing was perhaps the most exact and unbiased world-wide at that time. Much more precise than the English that looks a bit like driven by wish. Those who have spread such a fairytale are probably people who have no proper information or don't do the calculation correctly or just want to put doubt on the run of 05002. Juni had explained this in the trains forum, in the thread of "What compound for the US ..", I will repeat it here (copy and paste):

Ehr-hm, hi!

One more word on the three-cylinder engine:
I am no supporter of that engine when arranged as a compound. As a three-cylinder simple with 3 x 120° it alright and has its place and purpose. Still, that engine is not without some critical points in itself that have hardly been taken care of in regular steam times - for one: although the cylinders are significantly smaller than those of a comparable two-cylinder engine, frame demands are not easier but just different, loads are hardly diminished - why? because of the degree of cranking which provides a more counteracting work of the cylinders and since the frames are between the outside cylinders contortion of the frames is an important thing to take care of and look at from different angles. In that direction also go aspects of counterbalancing and cross balancing.

Side remark: I do not think this 'Eastern European' evaluation on the 05 was correct. Mind that A Wolff was one of the few engineers who took care looking into those matters, also the 05 were such 'long legged', if I may say so, engines that a typical proper frequency must if anything have been at lower, not higher rpm than with the smaller 01-10 / 03-10 three-cylinder engines of the same type of engine layout. For the 01-10, I know they had a peak of proper frequencies (a locomotive is not ideally stiff and therefore develops more than just one proper frequency) around 105 (worn engine) - 110 km/h - that relates to 279 - 292 rpm - way lower than the 05 ran at 200 km/h: 462 rpm. The smaller cylinders in the larger engine also contributed to keeping proper frequency at a rather low level. Indirect prove of this thesis came with the 18 201 that had larger cylinders than even the 01-10: 520 x 660 vs 500 x 660 mm. What made the situation worse was that the frames were lighter than those of both the 05 and the 01-10 since they stemmed from the original 61 002 a 4-6-6 three-cylinder tank engine of 390 x 660 mm cylinders. The rebuilt Pacific did develop a phenomenon of proper frequencies around 182 km/h that grew scary and demanded the cutting of the high-speed test. With the 05 no proper frequency phenomenon was to my knowledge experienced. If I estimate lower proper frequencies of the 05 relative to that of the shorter 01-10 as around 260 rpm, then the upper one would be around 520 rpm - relating to 225 km/h and thus still out of the way at 200 - 215 .. 217 km/h. From that point of view, the 05 had plenty of margin to surpass 200 km/h significantly.

I believe the point was as always with DR: you want to reach goals - but you never surpass them excessively. The goal originally was 150 km/h, quickly raised to 160 km/h the speed of the 'Flying' series railcars, finally raised to 175 km/h where it stayed. That speed had been fixed during the stage of collecting builder's proposals, long before the 'down fall' run of Mallard till hard against fatal destruction of the inner drive. No joke: destruction was already in progress: that was a typical British 'Sir Francis Drake' effort, or say it with Shakespear: it was to be or not to be! The Germans would be hard pressed to agree to such a risky all-out action. Also, mind that the reichsverkehrs-minister Julius Dorpmüller had accompanied the test run in the measuring car and his protection was above any wishes to allow a little 'piercing the unknown'. Still, the amount of 3400 ihp noted for 05 002 at the record run was way out of capacity for Mallard, whatever hard-driven, and given the importance of wind resistance at that speed range, this alone clearly indicates the 05 as the faster engine in the end.

Final recognition of what would happen in an all-out effort and what speed could be attained we could only learn if we took the engine out of the museum, undertake a complete revision, possibly equip her with DB given oil firing and have a go on modern high-speed track. As enlightening it would be, needless to mention this is as sure never to happen! Rests my remark that Mallard would not have come anywhere near to the 200 km/h mark without the help of the negative incline, not to mention slower acceleration might have caused unsustainable conditions to have developed already while at slower speeds than attainable by power output reached.

And now I haven't even mentioned the crocked curve of tractive effort development in a compound three-cylindder engine - and that applies to both the 3 x 120° and the 90 / 135° variation, only at differing work points.

Now, that could create extra and higher value proper frequencies!

Look at it from any viewpoint: the best of the compounds remains the four-cylinder type and in that the one with LP cylinders inside.

Juniatha

 
Added by Sara:
At least, at Maffei, I actually had received the modernisations concerning welded firebox and staybolts and tubes and flues. Besides this, little is it known that I did run 175 km/h one time in a test run after a 'Zwischenausbesserung' as it is called in German, a repair demanded by a mishap that had happened during regular running. In Germany to keep a certain 'service speed limit' in my cases still 175 km/h a locomotive is called to run at least 110% of this flawlessly for one time on a test run after an overhaul. Since there were no tracks on DB at that time to do that propely it seems it had been considered enough if I just ran those 175 km/h for one moment. A run with three coaches was made, one measurement car and two of the modern DB express standard coaches then newly delivered. The track was rattling under my tall wheels (fixed in frame, no sideways movement) and stroke the flanges times and again, but there was no instability whatsoever. I feel like even the boiler pressure had been raised for this one run to increase acceleration but I have no details if 18 or 20 atm nor anything about the way the decissions for this run were made or by whom. The run could (?) have been between Bremen and Osnabrück, on my way back to Hamm depot where all 05 were stationed, but today this is all very blurred ..
Sara 05003
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Posted by Sara T on Tuesday, March 30, 2021 7:52 AM

Jones 1945, 

if you mean these small smoke deflectors on the photo: these are properly called Witte deflectors because they were a German invention by Degenkolb in 1942 on the 52 class locos. They were universally introduced in 1948 following on DB by Friedrich Witte who then was about the German equivalent of a CME, Dez 21. Even on East-German DR they were called Witte deflectors, DR had their version a bit more bowed outwards like a sail. You see them on most German steam locos after 1950.

But there was a big difference between the successful proper Witte deflectors, or wings, as Juni calls them, and the unsuccessful PRR type: simply the German wings were positioned at the width of the loading gauge and reached forward before the smoke box front to catch the wind, the PRR ones were closely hugging to the smokebox and did not reach further than the smokebox drum, so they dodged the wind and were useless. I believe they are the sort of smoke wings those people like who don't like smoke wings at all, because they almost get lost hiding so close besides the smokebox drum. PRR only learned with the traditional so called 'elephant ears' which are of course an offense to the 'blank front end lovers'.

One drawback of the S2 I was told was the turbine and gear box that was held on bearings on the two driven axles and that ways were unsuspended, they were fully prone to the kicking and rattling of the rails of PRR's 'high speed track' with nailed rails and staggered joints left and right alternatively. Considering the delicacy of modern turbine engines of modern planes I wonder this turbine did withstand the punishment for years - or did it? The end came when the turbine was (again?) damaged and the loco stood in the shed at Crestline.  I believe it was the time when PRR was about to close the book on any steam loco that was not 100% standart and gave a minimum of a problem. I believe they didn't take no other look but just crossed them out for ever. Zzip and zzip and zzip! and in the end they crossed themselves out with one giant final ZZZZZIPP! and the whole system went PennCentral! Finally PC in agony also was about to suiczzzzzi..... but then there were others who's intentions differed. You know that better than me.

 

Sara 05003

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Posted by Overmod on Tuesday, March 30, 2021 12:06 PM

Sara T
One drawback of the S2 I was told was the turbine and gear box that was held on bearings on the two driven axles and that ways were unsuspended, they were fully prone to the kicking and rattling of the rails of PRR's 'high speed track' with nailed rails and staggered joints left and right alternatively.

The actual shock to the turbine blading was calculated by Westinghouse to be comparatively small; the torsional shock communicated through the drive was considered a far more important issue (and was addressed first in the provision of 'flexible gears' in the final drive and then in the installation of 'tandem' center side rods.  Apparently Newton's original drive was intended like Baldwin's of a century earlier to be geared 'separately' to the two inner axles (the ones sharing the floating gearcase and convenient sump) with the outer axles conjugated using quartered rods.  In the Baldwin 'development brochure' this is carefully glossed over; you see the 'full set' of rods illustrated together with construction photos to give the impression that was always the Baldwin intent, and only the stray picture of the locomotive without the center rods... and the interestingly ad hoc quartered cross-balance weights added to the rim of the two center driver pairs... hint that some design 'revision' was quickly engaged in.  It is not difficult to identify some of the possible reasons for that to be so.

In practice it might be possible to implement quill drive as on the GG1s from a 'floating' gear case similarly mounted to the frame.  Westinghouse designers were said to reason from maritime practice in high-power reduction-gear design, where unsprung mass of the 'final drive' is much less an issue.  If the center rods are absent, the gear case can be pivoted on the locomotive frame, with the suspension accommodation being analogous to that for nose-suspended motors; keeping the gears and bearings aligned and the oil sealing good were considered more important than low unsprung mass.

In any case the difficulty with most of the turbine blading comes with axial shock, particularly that which is hard enough to deflect rotating blading into stator blades or vice versa.  It is highly unlikely that a locomotive guided by coned tread and ¾" flanges will suffer transverse shock sufficient to accomplish that, let alone given the relatively high turbine shaft axis.

The situation on the N&W TE-1 of course was quite different, although the concern as described by Louis Newton was that a standing cut of hoppers was run in at over 8½ mph, something that no practical skid-based impact protection for turbogenerators or long-travel locomotive draft gear would likely be expected to absorb.  Even then the issues that led to the TE-1's retirement were electrical, not turbine, related... 

How the V1, both 'versions' of which were designed for longitudinal turbines, would handle this issue is less clear.  In the Bowes drive variant there is no direct contact between the turbine shaft and the final drive... unless the lockup clutch is engaged, which can communicate backdriving shock.  There would be a significant mass in the cast underframes that would essentially have to be accelerated before any transverse bending load on the blading would be developed, and while the shafting was part of unsprung mass the turbines (in part to keep flexible joints out of the steamlines) would be entirely spring-borne.

The issue of transverse shock factors more significantly into a counterrotating Ljungstrom turbine (where there are no fixed stator blades).  But here again providing good bearing support and tribology in the turbine shafting would be essential, and ensuring proper mesh, crowning, etc. of a fully-enclosed geartrain more important than low unsprung driver mass... for transmission designers!

An analogue here is the mounting of the Besler motors on the B&O W-1, which in my opinion has many aspects of mechanical suicide.  Roosen's alternative certainly seems to isolate a 'steam motor' better from direct road shocks.

 

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Posted by Sara T on Tuesday, March 30, 2021 2:09 PM

Overmod

the total unsprung weight of the drive plus housing plus bearings is certainly quite substantial if you look at the photos. That the gears inside the frames represent a double to the outside coupling rods is correct. I recall, that unsprung weight of steam loco driven axles was an issue against steam. Unfortunately, electrics with axle-hung motors presented an even larger unsprung weight and this caused some trouble with hammering into rail joints, even though joints on DR in the 1930s were perhaps much better kept level than on the PRR who always tried to save maintenance, most of course in and after WWII. If the turbine loco had its all gear and housing fully on two axles (the mentioned electrics had their motors only 1/2 on axle 1/2 on bogie frame) that must represent a real rail hammering device and must be 'killing' rail joints in FFM (fast forward motion). There must have been a lot of vibration in this device on the jointed, nailed track, heavy vibration. To have a very fast rotating turbine with its blades mounted in this casing cannot have been optimal. Perhaps this turbine was specially sturdy made to withstand this ruttling, but good is something else and it must have gone on quality of efficient working which demands to keep clearances around the blades as small as possible. Why didn't these designers take a look at drives in electric locos which by then were much further advanced? They could have saved the flexible part in steam conduct also. I believe a completely unsprung driving device is something you could perhaps have as a first realization to get the locomotive work at all somehow. But it would surely be intolerable if more of these locos would appear. Reason for being of the first loco would then have had to try better solutions until they find one that works well.

Again, time was closing down on steam and the diesel proposers did want one thing the least: that steam engineers should find solutions for the troubles that plagued the various turbomotives and that a presidential office would give them a chance. So it meant a 'putting out fires' for the diesel guys, quick and completely and definitely, in order to make their revenue.

Sara

 

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Posted by Overmod on Wednesday, March 31, 2021 2:15 AM

Sara T
I recall, that unsprung weight of steam loco driven axles was an issue against steam. Unfortunately, electrics with axle-hung motors presented an even larger unsprung weight and this caused some trouble with hammering into rail joints...

Look more carefully at the forces actually involved here, for example at discussions of the relative stability of the locomotive types developed for the PRR North River tunnel project (that culminated in the DD1) or at Burch's Electric Traction for Railway Trains (1911), both of which are windows into comparative steam vs. electric track damage.

Many of the early references indicate there was far more damage from lateral impact than vertical.  Among other things this caused damage to the 'nailed' track in directions it was ill-designed to resist effectively, and that would require additional care to re-line as well as re-surface.

 The imposition of adhesion weight on the driver axle far exceeds its unsprung-mass inertia, which of course is also why overbalance is tolerable at all in conventional balancing.  Since long-travel suspension is not easily accommodated in quartered-rod drive, much of the theoretical advantage in shock mitigation from lower driver mass (by false analogy with road-vehicle suspension) won't properly apply to the coupled wheelbase; in fact the lighter the driver, the greater the impact from hammer-blow once it develops past adhesive weight and you get into 'bouncing drivers' as in those AAR films of the hapless C&NW E-4 in the late '30s...

If the turbine loco had its all gear and housing fully on two axles (the mentioned electrics had their motors only 1/2 on axle 1/2 on bogie frame) that must represent a real rail hammering device and must be 'killing' rail joints in FFM (fast forward motion).

It is important to remember that the weight of the gearcase is carried on the frame, and could easily be spring-borne just as frame-mounted electric motors with fixed gear cases to bull gears are.  In the case of the S2 this case is essentially pivoted in its mount, so any contribution to shock that it makes is not vertical but related to the radius from pivot axis to contact patch.  Meanwhile the lion's share of adhesive weight is imposed the normal way for any locomotive of this size, through equalizers and springs... I can't find a good diagram that shows this carefully but some discussion of it ought to be in the running-gear patent (Locomotive Drive 1 and 2, probably dated Aug 26 1943 but Google is being close-fisted finding the reference on a phone).

Nowhere in what remains of the S2 accounts do I find any discussion of untoward shock or impact; in fact there are a number of reports stressing the relatively good riding characteristics ... of course, this was assessed compared to contemporary reciprocating power, and reciprocating locomotives  are never particularly likely to be kind to track in vertical shock, even duplexes.

It does occur to me that much of the modern detailed study of steam-turbine locomotives, specifically including the S2, is in fact in German, so you may already be familiar with details not readily known to (or remembered by) Americans outside a dwindling community of PRR specialists.  If so please reference them.

Obviously a suspension like that in the 'improved' V1, which would have used cardan-shaft drive to individual axle gearcases, ought to be somewhat better with respect to shock.

Roosen's design preserves the advantages of relatively tall wheels combined with the isolation of a reasonable quill drive (albeit driving only from one end of each driver pair).  One of our great national shames was not preserving the example we looted... although it does have to be said that great efforts were made to get what was then DB to take it back -- no one there or here wanted any part of developing the idea by the late '40s, just as B&O dropped the Besler constant-torque almost like a brick nearly a decade earlier.

There must have been a lot of vibration in this device on the jointed, nailed track, heavy vibration.

It would be interesting to see whether systemic effects of vibration were that severe; I suspect a better way to express the concern is repeated impact shock, unlikely to induce or sustain a critical resonance.  

Westinghouse claimed, and had, long experience in 'what worked' with geartrains on locomotives as well as in marine practice.  I note that turbine gearing elsewhere in the world... where it was successful... featured very heavy gearing and good alignment and support, with comparable mass, in the final drive.

To have a very fast rotating turbine with its blades mounted in this casing cannot have been optimal. Perhaps this turbine was specially sturdy made to withstand this rattling, but good is something else and it must have gone on quality of efficient working which demands to keep clearances around the blades as small as possible.

Keep in mind that this is not an aerospace turbine, it's a steam turbine, with the additional clearances appropriate in the Rateau interstages at least, and with significantly more constraints on effective tip sealing (which in any case is the thing vertical vibrations derived from low "quaintly nailed" joints and the like would impose on the 9000rpm not-very-large main-turbine rotor.

Now whether there was cumulative blade-root or disk damage from cumulative shock effects, I don't know; whether this led to sufficient tip interference to induce circumferential bending failure if the blading I likewise have seen no records for.  However, I doubt shock loading sufficient to Brinell the turbine-rotor bearing races or thrust-bearing surfaces, let alone deflect the shaft sufficient to cause blade strike, would be observed -- certainly the Westinghouse engineers who did the detail design and well understood the likely stresses would have considered this, and would have remarked on the need for design remediation if in fact problems were observed.

Why didn't these designers take a look at drives in electric locos which by then were much further advanced? They could have saved the flexible part in steam conduct also.

I know it is fashionable to consider dead white men from the Thirties fundamentally incompetent in engineering knowledge or practice.  But it can be surprising to find that in many cases they did, in fact, actually understand these things and make reasoned choices, often guided by empirical wisdom and experience of practical factors.  Westinghouse in particular could be expected to have considerable institutional knowledge of electric locomotive drives as well as how to apply their salient characteristics to other rotary power than electric motors of various types.  It would have been interesting to see the detail design of the 4000hp V1 turbines... and, perhaps, how the design evolved as the transmission options and chassis 'desiderata' changed in the late '40s... but it appears that this was lost at the time the 'adjacent' detail for the Westinghouse turbine in the N&W TE-1 was 'dumpster-dive' recovered, sometime in the late 1970s if I recall the story correctly.

By no means does any of this relate to modern practice even in the 110-to-125mph HrSR range.  Any modern high-speed design will involve low unsprung mass and very competent arrangements for compliance and damping.   This has historically resulted in some strange decisions, the choice of long-wheelbase truck on the test E60 and the substitution of heavy drop-equalizer GSC trucks on the Metroliners being but two that come painfully to mind.

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Posted by Overmod on Wednesday, March 31, 2021 3:06 AM

Sara T
Overmod, you wrote:
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...
I'm sorry but this is all wrong. There never was such a problem...

That claim was taken from a study which I can no longer readily find on the Web (at least not on a phone...)  That is quite possibly because either its methodology or its conclusions might have been found to be flawed, and its authors have taken it down.

There is now a subsequent (and, I think, much better executed) study of the 05 kinematics, described here:

https://www.yumpu.com/en/document/read/4855279/the-hunting-stability-of-the-german-high-speed-steam-simpack

As their initial methodology appears similar to some of the analysis conducted for the T1 project (5550) I am comfortable in stating the results would be much more reasonable than "that other study".  Note in particular the emergent behavior illustrated in their Figure 7 -- note the equivalent speed, and that the oscillation appears to be self-limiting when established.

As noted, they identify a problem with the engine-tender coupling, which they expect around 225km/h; as German practice is one of the places effective engine-to-tender coupling and guiding improvement can be found, I have little doubt that Adolf Wolff or others like him would have had little difficulty mitigating this were speeds that high deemed desirable.

I thought many years ago that a problem with the testing was 'quantization' to the metric 'double ton' -- testing was made to reach the magic 200km/h with little incentive to push the performance envelope further... as the Mallard people found the excuse to do.  It is not lost on me that LNER, despite quickly and I think effectively fixing the detail-design problems in the inside big end never saw fit to operate remotely in that speed range again.  Perhaps for the best; I thought then and still think now that most of Mallard's advantage was small frontal area imposed by the toylike British loading gage, a nominal advantage likewise possessed by the Milwaukee A class (which Alfred Bruce claimed in print, not something to take lightly from such a one in such a position, easily exceeded 128mph).

You will note the curious specificity of that 128mph number.  That is not intended to compare with the verifiable British surge of 125mph or the fake 126.1: it specifically establishes a speed meaningfully faster than the likely-fudged PRR 'record' of 127.1 between AY and Elida, the American 'folk speed record' we all learned about as children.

It is readily apparent to me that the 05 is generally a more competent high-speed design than the Milwaukee 4-4-2 in a number of significant respects, and as far as I can tell inferior to it in none.  While of course I don't expect to see the 'historic' locomotive released from Nuremberg any sooner than Mallard would be restored from York, we certainly already have recreated sufficient base of industry and skill to replicate the locomotive from plans, and indeed to improve its materials and some of its proportions and systems as for the T1.  Some slight additional complications would be involved in testing this at high speed (e.g. properly instrumented wheelsets) but no particular problem in allowing operation to 165mph exists once the locomotive is 'in being'.  (And note that this is barely over the point at which kinematics first identify a self-limiting resonance in guiding...)

While I confess my first loyalty is still to the Lost Cause of divided drives, the second project ought to be a revived 05 in all its optimized splendor.  Whether or not it whips the tar out of 5550 on test.

 

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Posted by daveklepper on Wednesday, March 31, 2021 3:57 AM

What a truly wonderful collection of ideas and facts you have presented!  May your dreams come true!

My comparable dream?

The rejuvinated GG!, with the motors and the frame from the best from all existing displayed, rewound motors with best possible insulation, high-capacity solid-state-diode rectification for DC operation of the original motors, special custom 25 Hz and 60 Hz tapped transformer (audio-transformere technology increased in scale), no asbestos, with original transformer-tap control restored, automatic changeover for change of power frequency, authentic Brunzwick Green with gold pin-stripes, and a matched set of Budd Senator-Congressional cars.

And I'd settle for 120 mph, just high enough not to bog down other NEC movements.

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Posted by Jones1945 on Thursday, April 1, 2021 1:59 AM

Sara T
Jones 1945,  if you mean these small smoke deflectors on the photo: these are properly called Witte deflectors because they were a German invention by Degenkolb in 1942 on the 52 class locos. They were universally introduced in 1948 following on DB by Friedrich Witte who then was about the German equivalent of a CME, Dez 21. Even on East-German DR they were called Witte deflectors, DR had their version a bit more bowed outwards like a sail. You see them on most German steam locos after 1950.

Thanks, Sara. Speaking of Witte deflectors, I am a big fan of them when I was so much younger. In almost 80% of my locomotive drawings, I put them on the steam engine for decoration. When I was a kid, I thought they were a device for stabilizing the locomotive at high speed. I still found them looking cool on those German steam locomotives nowadays.

For the first version of smoke deflectors that were equipped on the S2, I considered them a unique type. They really reminded me of those small-size smoke deflectors installed on B&M's Pacific and Class R1 (mountain) more than those German wings. Maybe it was because they were not positioned exactly the same as the German wings.

B&M's Mountain and Pacific:

 

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Posted by Flintlock76 on Thursday, April 1, 2021 9:27 AM

The smoke deflectors on those B&M locomotives ar OK, but that skyline casing on the R1 looks a bit weird.  

So does that plate half-way back on the R1's boiler.  I wonder what that's for?

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Posted by M636C on Thursday, April 1, 2021 7:23 PM

Flintlock76

The smoke deflectors on those B&M locomotives ar OK, but that skyline casing on the R1 looks a bit weird.  

So does that plate half-way back on the R1's boiler.  I wonder what that's for?

 

Do you mean the cover plate over the sand pipes?

The casing on the Pacifics didn't last long and the second batch wasn't fitted with the casing.

The B&M Pacific was the prototype for the Athearn model.

Peter

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Posted by Juniatha on Thursday, April 1, 2021 9:40 PM

Overmod,

you may write pages and pages of blurrings and specialized special views. What remains, I must consent to Sara's remarks in general - and they were meant in general - there is no way to cover up:

1. - a heavy block unsprung - Westinghouse or other - on the two axles cannot be good for jointed rails

2. - hard vertical shocks on a rotating turbine - and it doesn't matter what exactly was the amplitude or the impact, it was heavy in any ways - cannot be helpful for keeping it in running order. Don't try to let on Westinghouse had tons of experience in railway application of turbines: where were the respective engines? Never heard of.

Full stop.

Juniatha

 

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Posted by Erik_Mag on Friday, April 2, 2021 12:06 AM

Juniatha

2. - hard vertical shocks on a rotating turbine - and it doesn't matter what exactly was the amplitude or the impact, it was heavy in any ways - cannot be helpful for keeping it in running order. Don't try to let on Westinghouse had loads of experience in railway application of turbines: where were the respective engines? Never heard of.

Westinghouse built turbines for warships, which would be subjected to hard shocks, especially in the case of a battleship with large caliber naval rifles.

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Posted by Juniatha on Friday, April 2, 2021 12:51 AM

Sara wrote "I feel like even the boiler pressure had been raised for this one run to increase acceleration but I have no details if 18 or 20 atm nor anything about the way the decissions for this run were made or by whom."

Considering the bureaucratic ways in Germany, this could only have been an incident "auf dem kleinen Dienstweg" - I have no idea how to translate that into English, the whole idiom may not exist outside Germany, maybe "on lower official channels" might give an idea, meaning to avoid to make something happening known to higher ranks: one "Abnahme-Inspektor" - acceptance report inspector - may have made that speed plate a basis for realizing his personal wish to "see what she could do". Officially, any speed above 100 or 110 km/h - ~ 60 to 70 mph - was then of no importance. It must have been on a section of track only recently rebuilt, I would be inclined to think for a save approach they had made several runs augmenting speed in steps. As to the increased bp, I tend to think it was 18 bars rather than 20 because with the boiler of formerly 20 bars, a temporary 18 bars would have been save in every aspect, and with a light load of 3 cars, it would have been enough. 18 bars was officially introduced with the class 10 heavy Pacific. From the boiler output with the standard 05 specifications of draughting which was likely considering the March 1945 rebuilding, the combustion chamber boiler with shorter tubes - of a different layout - would have reacted significantly more lively than the standard Wagner boiler and would support, say 53 -> 50% c/o for acceleration from 150 -> 175 m/h - 93.2 to 108.7 mph. This would produce ~ 3000 ihp at 175 km/h - quite 'enough' for good acceleration with that light load.

It should have been a great sight to see her run by at that speed with steam plume raised clearly above the boiler and a fast roar coming from the three-cylinder engine!

Juniatha

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Posted by Juniatha on Friday, April 2, 2021 1:11 AM

Eric, yeah, they were subject to hard shock when hit by a torpedo - sure. But then it didn't matter so much how many more hours turbines would make ...

Seriously: The shock caused by firing cannons cannot have been anyway near the shocks unsprung on rails - just check the relation of masses between the ammunition and the ship - and then there was flexing of the hulk: a long way between board cannons and a turbine deep down in the vessel. Very small vibration and subdued by the entity of the hulk in the water - no, I don't see any proper analogy to railroading.

Juniatha

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Posted by Overmod on Friday, April 2, 2021 8:06 AM

Juniatha
1. - a heavy block unsprung - Westinghouse or other - on the two axles cannot be good for jointed rails 2. - hard vertical shocks on a rotating turbine - and it doesn't matter what exactly was the amplitude or the impact, it was heavy in any ways - cannot be helpful for keeping it in running order. Don't try to let on Westinghouse had tons of experience in railway application of turbines: where were the respective engines? Never heard of.

Neither issue is argued.  I find the Westinghouse design unfavorable and have repeatedly said so; the argument here is that they had their reasons to design it that way, knowing extensively the advantages of quill drive in locomotive 'transmissions'.  If they were wrong, it was not from ignorance.

It is a truism to observe that uncushioned running shocks are 'not helpful in keeping a turbine in running order'.  The specific issue here is whether either the prompt or cumulative damage from transverse shock to this (comparatively small) turbine is less than axial shock would be, and I believe this has been reasonably established in both the steam and gas-turbine industry.  Nothing beyond that is implied, certainly not that I personally think there would be little or no damage to any 'uncushioned' turbine over time.  Certainly in my own designs (which use far better bearing technology than was practically available in the '40s) I have been very careful to account for potential shock and impact.

 

 

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Posted by Flintlock76 on Friday, April 2, 2021 8:32 AM

Erik_Mag

 

 
Juniatha

2. - hard vertical shocks on a rotating turbine - and it doesn't matter what exactly was the amplitude or the impact, it was heavy in any ways - cannot be helpful for keeping it in running order. Don't try to let on Westinghouse had loads of experience in railway application of turbines: where were the respective engines? Never heard of.

 

 

Westinghouse built turbines for warships, which would be subjected to hard shocks, especially in the case of a battleship with large caliber naval rifles.

 

Apples and oranges man, those warship turbines were WELL protected down in the bowels of those ships.  The firing of the big guns wouldn't bother 'em at all. 

In fact, when many warships with turbine engines were scrapped the engines were typically in as good a condition as the day they were made.  

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Posted by Overmod on Friday, April 2, 2021 9:26 AM

I would suggest that any issue related to turbines or gearing arrangements in warships is much more related to prospective shock from 'the other end' of naval rifles, and by extension torpedo hits as Juniatha indicated.  Possibly-complex interaction of shockwaves communicated from high-order detonation on what might be highly-stressed machinery would be the thing of concern there, and it is my understanding that even the largest naval rifles have been installed not to communicate supersonic shock directly to the ship's structure when fired.

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Posted by Overmod on Friday, April 2, 2021 9:39 AM

It occurs to me that Juniatha may know, or have thought about, the specific failure details of the Guy turbine in the LMS Turbomotive.  This was arranged with transverse axis, but as I recall had a relatively larger rotor diameter.  This was supposed to be a shaft fracture at relatively high speed under load, leading directly to catastrophic blade interference damage.  It is quite possible that analysis of the failed shaft would exhibit signs of cumulative shock damage communicated transversely through the bearings; on the other hand, I think there are forces that could be applied via the rotor to the shaft in bending that might induce stress raisers in ways less likely for the longer, thinner Rateau-stage Westinghouse design to develop.

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Posted by Sara T on Friday, April 2, 2021 2:49 PM

Overmod, I read yours: >>Certainly in my own designs (which use far better bearing technology than was practically available in the '40s) I have been very careful to account for potential shock and impact.<<

That would really interest me!

Would you post one design sketch?

Sara 05003

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Posted by Sara T on Friday, April 2, 2021 3:15 PM

Juni, about your:  

>>I would be inclined to think for a save approach they had made several runs augmenting speed in steps.<<

That may have been so. Mostly of course the final run stayed best in mind. I don't see all that so easily and so clearly. Juni, you know, but to other participants:  mind that 99.999 % of people have NO, absolutely NO vision of ANY former life of their's and most of them wouldn't want to know, because it would shock them! It is wisely so arranged that people live free from former memories. Mine isn't so bad after all, I have made a huge advance from machine then to human now, but what about people having been murderers or perverts or have become victims of raping or slaughtering? They better have no premonition of anything!

So it isn't all that easy for me, I could go meditating into it, but I wouldn't do it alone once again as I did earlier one time before I knew what would await me there. What if didn't come back alright or not quite or any other mishap would happen? Also, it is not such a happy experience, so I have little appeal to dig out more than I have. Let's just leave it at what it is.

Sara 05003

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