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Franklin B rotary cam poppet valves

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Franklin B rotary cam poppet valves
Posted by natelord on Tuesday, April 13, 2004 11:42 AM
Were C&O's L-2A Hudsons--the post World War II--ones the only U.S. class of steam engine equipped with these valves? Incidently, how did the performance of that class compare with the pre-war L-2s?
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Posted by M636C on Wednesday, April 14, 2004 6:57 AM
No, there were a small number of other locomotives fitted with Franklin Type B rotary cam poppet valve gear.

Santa Fe 4-8-4 No 3752, Pennsylvania K4s 4-6-2 No 3847 and T1 4-4-4-4 No 5500 and US Army 2-8-0 No 611 were all fitted with Franklin Type B valve gear.

All these locomotives were rebuilds, and the C&O 4-8-4s may have been the only locomotives built new with Franklin Type B valve gear.

The statement has been made that T-1 No 5500 was the best of its class after rebuilding with Type B gear, so it is likely that the C&O locomotives were similarly better than conventional locomotives.

Peter
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Posted by Modelcar on Wednesday, April 14, 2004 8:53 AM
...Boy, 611....., that's a famous number...only the one I'm thinking about is the J-3 NS engine that visited Muncie with it's trail of various passenger cars filled with fans. It was a guest here a half dozen times or so in the I suppose late 80's....What a shame it travels no more.

Quentin

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Posted by CSSHEGEWISCH on Wednesday, April 14, 2004 12:41 PM
Most varieties of poppet valves resulted in improved performance when they were installed. The downside was that the locomotives with poppet valves wound up being oddballs on the roster with the usual poor maintenance as a result.
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 Anonymous on Wednesday, April 14, 2004 1:56 PM
The US Army Transportation Corps sent one of its 2-8-0's, no.2628 to Baltimore to test the Franklin system in the early 50's on the Maryland & Pennsylvania. The M&P loved the engine and got several extentions on its use. I understand the engine is still around, after a sort; it's a rusting hulk on Texas State RR the last I heard. The 2628 was later renumbered 611, if I recall...
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Posted by wallyworld on Thursday, April 15, 2004 7:41 AM
On the Pennsylvania RR, the first use of poppet cams was the “Type A”, which was retrofitted on K4s 5399. This change may have produced the whopping 24% more power at 60 mph and 44% at 80 mph in road trials. However, some felt that since the engine was a 1914 design that the actual improvements in performance were due to the redesign of steam passages and a reconfigured superheater. The Type B was installed on K4s 5436 in 1940 and later retrofitted on 3857 in 1945. It’s really a shame the Type B was never used on a T1 Duplex. By this late date, the use of Type A’s kept the T1’s in the shop and the conversion to diesel power tipped the balance and so after 1946, no further development work was done. The inaccessibility of the gearboxes on Type A’s were a maintenance headache.

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Posted by M636C on Thursday, April 15, 2004 8:16 AM
Wallyworld,

"Pennsy Power III" by Staufer, page 175, shows K-4s 3847 with rotary cam gear.

On page 205, T-1 5500 is shown with external rotary drives for Type B poppet gear "after being involved in a wreck in the St Louis area". The drives are the same as those shown on 3847.

Also on page 205 is a photo of T-1 5547 with piston valves and Walschaert gear, and even it was thought to be better than the standard T-1.

But there is no question that the EMD E-7s were much, much better than the T-1s, and entered traffic about the same time.

Peter
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Posted by wallyworld on Thursday, April 15, 2004 6:23 PM
M636C- Thanks- Wow- That's a very interesting bit of additional information I was unaware of. One of my favorite subjects is the Pennsy, especially in the transition era.
Do you know if they ( The T1's ) were ever tested either on the stationary test bed or on the road?
Outside of easier maintenance access, was the horsepower upped as in the case of K4s? I just finished a great book called Black Gold-Black Diamonds by Eric Hirsimiki on this topic and oddly the T1's were listed as unmodified.

Nothing is more fairly distributed than common sense: no one thinks he needs more of it than he already has.

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Posted by M636C on Thursday, April 15, 2004 8:03 PM
wallyworld,

I'm pretty sure that one of the first two T-1s was tested, and I think there are some figures in Vernon Smith's "One Man's Locomotives". Smith worked for Franklin (which was really part of Lima) and there is a lot of interesting information about early work with the 5399 and 6110 and 6111.

Staufer implies that 6110 and 6111 worked really well, and the major problems only showed up with the 5500 series. However, World War II occurred between those dates, and there may have been a big difference between the way two special locomotives were treated (before WWII) and a fleet of 50 in normal service afterward.

As I understand it, no T-1 showed the sort of improvement expected from results with the first modified K-4s.

Peter
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Posted by Anonymous on Thursday, April 15, 2004 8:14 PM
When I went to Horseshoe curve over the summer, I purchased a CD of PRR locomotive 'sounds", in which a narrater points out the differance in sound that the poppet valves on one locomotive had.
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Posted by eastside on Friday, April 16, 2004 12:36 AM
How about another 5500, the NYC class S2a Niagara? In the books I have they don't specify which type (A or B). Staufer ("NYC Steam Power") says they never ran formal tests.
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Posted by M636C on Friday, April 16, 2004 1:00 AM
eastside,

I forgot about NYC 5500, but I think it had Type A poppet valve gear with inside drive gear, like the other PRR T-1s (apart from PRR5500 and 5547). I don't recall it having the eccentric gearbox on the drive axle or the rotary shaft outside in the location you would expect the Walscheart gear. I'll check!

Peter
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Posted by M636C on Friday, April 16, 2004 5:58 AM
eastside,

Photos show NYC 5500 to have Type A poppet valves.

Peter
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Posted by wallyworld on Friday, April 16, 2004 8:11 AM
Peter,
Thanks for the information-It looks like I'll be making another book purchase.
I don't know if you are interested in recent steam development but there is an excellent book by an an engineer named David Wardale which is entitled "The Red Devil: And Other Tales From The Age of Steam" He was part of the ACE team and did work for China as well as South Africa in modernising steam motive power. It's a great read.

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Posted by M636C on Saturday, April 17, 2004 6:13 AM
Wallyworld,

I've checked Vernon Smith's book, and PRR 6110 was tested at Altoona in 1944. One table shows 6666 Indicated HP at 100 MPH, and another table shows 6000 Drawbar HP at 70 MPH. Remember that that required three E-7s which must have cost a lot more to buy!

I have Wardale's book, which is pretty good. I also have the translation of Chapelon's "La Locomotive A Vapeur" (the title wasn't translated), which is very interesting. There are a number of good books in German, which I can (just about) read. A couple of English books by E.S.Cox, particularly "World Steam in the Twentieth Century" are worth reading. Cox was largely responsible for the British Railways Standard Steam locomotives, and there's a good book on them too! They were extensively tested both on the road and on a static plant.

My personal interest is in China, and some day I'll finish rewriting a new edition of my book "Locomotives in China". (published in 1984). The development of the QJ is a particular interest of mine. It was basically assembled from standard Russian parts, and is apparently the work of Lebedyanski, who was responsible for the Russian L and LV classes.

I actually have a photo of the QJ that Wardale was working on, but before any changes were made to it. It was stored complete at Datong in 1985. A friend visited Datong, and had a couple of meals with David Wardale while he was working there. Much of the frustration Wardale experienced was made clear at that time. However, I didn't think that the standard QJs were quite as rough and ready as Wardale indicates. They do look and sound good in service.

A couple of 4-6-4s were rebuilt to Wardale's principles for limited service out of Melbourne, Australia. They've had some problems with the valves - the tighter tolerances to reduce steam consumption caused some overheating problems. Lubrication problems with superheated steam have been around for at least a century. I don't think the angled stacks (like the "Red Devil" ) look very good, and they might not improve performance that much.

Peter

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Posted by wallyworld on Saturday, April 17, 2004 7:44 AM
Peter,

Thanks for the additional information. The T1 results with Type B cams is really impressive. Its a shame the Pennsylvania was under such economic pressure
that further experimentation wasnt practical. The books sound great-and now I just have to find a decent book vendor for these purchases. I read that Wardale is proposing a new generation steam loco for excursion service-do you know if he made any progress? I have a video of the Red Devil at speed and it made a lasting impression on me. Here is a large locomotive flying along with it's rods spinning in a blur..no smoke--no exhaust beats-it sounded like a sewing machine on steroids.The QJ Class is impressive inasmuch it seems to have done it's job well enough to be relied upon for a variety of assignments for quite a while.I had always hoped one one have been exported by now for excursion service.

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Posted by M636C on Saturday, April 17, 2004 9:43 AM
There is a QJ in Japan, where it was sent for a rail exhibition. It is unlikely to be allowed to run on the Shinkansen, which would be the only standard gauge with clearances suitable for it.

I would think there are still enough QJs for one to be imported to the USA. Some changes might be required to the boiler to meet US regulations.

The British "excursion locomotive" is associated with the "Locomotives International" magazine, and I think details are on their website. I think that there are already so many proposals for new locomotives, to traditional designs, that this "5AT" (I think) locomotive may not get enough support.

I'd prefer to see efficiency improvements made with minimal appearance changes, to one of the several locomotives in that power class already preserved. At least one fitted with rotary cam valve gear, No 73129 (I think) is in working order.

The 3-cylinder class 8 4-6-2 "Duke of Gloucester" had new rotary cam cylinders fitted (the originals were cut open as a museum display). It had new blastpipes and grates fitted, including correction of construction errors in its air intakes in the ashpan, and it is apparently much more powerful and economical than when in regular service.

Peter
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Posted by GT_Mills on Thursday, October 15, 2020 10:22 AM

M636C
No, there were a small number of other locomotives fitted with Franklin Type B rotary cam poppet valve gear.

Santa Fe 4-8-4 No 3752, Pennsylvania K4s 4-6-2 No 3847 and T1 4-4-4-4 No 5500 and US Army 2-8-0 No 611 were all fitted with Franklin Type B valve gear.

All these locomotives were rebuilds, and the C&O 4-8-4s may have been the only locomotives built new with Franklin Type B valve gear.

The statement has been made that T-1 No 5500 was the best of its class after rebuilding with Type B gear, so it is likely that the C&O locomotives were similarly better than conventional locomotives.

Peter
 

Correction:  That's 4-6-4, not 4-8-4. 

I never knew that this was the only locomotive to be built originally with Franklin poppet valves.  This is mind-blowing, considering Watt used poppet valves in his steam engines almost two centuries prior!  

 

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Posted by Overmod on Friday, October 16, 2020 12:45 PM

GT_Mills
I never knew that this was the only locomotive to be built originally with Franklin poppet valves.

Note that this was far from the only locomotive built with 'Franklin poppet valves' -- all the T1s as built had them, and they were very specifically retained as built on the T1 rotary-cam conversion: that is what the "type B-2" denotes, the use of bridges to actuate the pairs of valves from type A OC using the rotary-cam arrangement proper to three-valve type B.

As I understood it, the RC arrangement on the L2b did not provide substantial 'enough' improvement over the 14" piston-valved version as C&O used these (extremely heavy) locomotives.  I have lost the technical material (some of which may be in the '47 Cyc along with the description of continuous-contour shifting-cam RC) on precisely what the Franklin installation on the late Hudsons was; if continuous contour it would have suffered from the line-contact issues; if multiple fixed cams it would have had inferior intermediate cutoff control to the engines with Baker gear...

I don't recall if the cracking problem (with heavier 'return' springs for expedient debouncing of the poppet valves at speed) extended to the L2b valves; some of the 1948 planned improvements to the PRR T1s, specifically including better metallurgy and centrifugal casting for the valve spools, might have been incorporated on them considering their relatively late build date.

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Posted by Paul Milenkovic on Friday, October 16, 2020 7:20 PM

M636C
Wallyworld,

I've checked Vernon Smith's book, and PRR 6110 was tested at Altoona in 1944. One table shows 6666 Indicated HP at 100 MPH, and another table shows 6000 Drawbar HP at 70 MPH. Remember that that required three E-7s which must have cost a lot more to buy!

I have Wardale's book, which is pretty good. I also have the translation of Chapelon's "La Locomotive A Vapeur" (the title wasn't translated), which is very interesting. There are a number of good books in German, which I can (just about) read. A couple of English books by E.S.Cox, particularly "World Steam in the Twentieth Century" are worth reading. Cox was largely responsible for the British Railways Standard Steam locomotives, and there's a good book on them too! They were extensively tested both on the road and on a static plant.

My personal interest is in China, and some day I'll finish rewriting a new edition of my book "Locomotives in China". (published in 1984). The development of the QJ is a particular interest of mine. It was basically assembled from standard Russian parts, and is apparently the work of Lebedyanski, who was responsible for the Russian L and LV classes.

I actually have a photo of the QJ that Wardale was working on, but before any changes were made to it. It was stored complete at Datong in 1985. A friend visited Datong, and had a couple of meals with David Wardale while he was working there. Much of the frustration Wardale experienced was made clear at that time. However, I didn't think that the standard QJs were quite as rough and ready as Wardale indicates. They do look and sound good in service.

A couple of 4-6-4s were rebuilt to Wardale's principles for limited service out of Melbourne, Australia. They've had some problems with the valves - the tighter tolerances to reduce steam consumption caused some overheating problems. Lubrication problems with superheated steam have been around for at least a century. I don't think the angled stacks (like the "Red Devil" ) look very good, and they might not improve performance that much.

Peter
 

 

Tell me about La Locomotive a Vapeur.  Not that I will be able to get my hands on either the French language version or the English translation, but how does it compare with, say, Wardale's The Red Devil?

I had thought the Red Devil would have much more technical information than it does, but it is largely Wardale complaining about what a hard time he had, first in South Africa, then in the US and finally in China.  Three separate attempts to "bring back steam", three failures reflecting differences in the engineering culture in the three countries at that time.

The Red Devil is replete with graphs meant to show performance improvements, but it is lacking in a lot of other detail.  To me, its biggest failing is that it starts out claiming that the Gas Producer Combustion System is the answer to the carbon-carryover problem and part of the answer, along with Chapelon-style improved exhaust and reduced steam-circuit pressure drops.  Wardale makes some outsized claims of the improvements in water and coal economy, but as you get deeper in the book, the improvement of the Red Devil is shown to be more incremental when data is collected in actual service.  Little explanation is offered to show why apart from blaming crews that they "lacked enthusiasm" to operate the GPCS properly.

Can you give me a sense of what La Locomotive a Vapeur is like?  Does Chapelon show economy and power improvements and give detail as to where they are coming from and under what service conditions?

If GM "killed the electric car", what am I doing standing next to an EV-1, a half a block from the WSOR tracks?

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Posted by Overmod on Saturday, October 17, 2020 7:40 AM

The translation is by Carpenter.  It does not redraw the French graphs and exhibits, much as the Wasatch translation of 'Rear Boiler Knowledge' from Glasers Annalen does not.  Among other things it contains Chapelon's useful Sherlock Holmes deduction on how Timken thin-section rods can possibly work with roller bearings.

All the calculations were to be in 'part 2' of LLAV, which was never reprinted after the original edition (in French) and as I recall much of it was never printed at all.   Discussion of this on steam_tech was extensive but now 'lost to science' with the collapse of Yahoo Groups; it remains to be seen if the archives or collateral are restored on groups.io.  I recommend that you review anything remaining on the Web by Thierry Stora or Claude Bersano before it, too, gets taken down...

I was sent a page scan of the 1938 edition to do a full translation of the 'missing' part ... and should get back on it!

GPCS is in part founded on a mistaken understanding of heat transfer in a locomotive boiler; it resembles some of the misunderstanding of the thermodynamics of Besler tubes.  Effective heat release is only part of the concern; it must then be taken up effectively and then communicated to water in ways that facilitate generation of suitable 'power steam'.

Products of combustion transparent across a wide portion of the emission spectrum are not as effective at radiant heat transfer as the luminous flame from vaporized (but unoxidized) carbon.  Uptake from transparent gas is likewise peaky in the tubes; hence heating of a blackbody followed by re-radiation nearly normal to a (similarly black) tube wall has enhanced heat transfer benefits in addition to increased convective transfer in an annular restriction.  In a boiler where there is no practical effort to recover the heat from the (transparent) H2O in the gas stream -- in GPCS this deriving not only from combustion but the 'process steam' introduced in the cellular windbox -- still more Rankine efficiency is thrown away.

Wardale acknowledged at one point that GPCS was a chemical reaction, not a firing method.  Just as chemical reactions benefit from intricate process control, and often go haywire without it, so we can reasonably expect large-scale GPCS in tight packaging to be; if we now expect it to follow what is already a complex load-following steam demand it may become clear that no human fireman can consistently make all the various often interrelated adjustments in realtime... or perhaps better stated, shouldn't be expected to.

This isn't to say that some of the ideas of GPCS are mistaken.  The idea can be adapted to produce a luminous primary plume with the addition of preheated primary air in addition to process steam, and to preclude clinkering and other ash-glassing problems (it would be nice to have cyclone firing on a locomotive but there are considerable issues!).  Part of the reason for a cellular windbox is to permit different parts of the bed to be selectively 'blown' at different times and at different rates.

The angled stacks are not 'new' to Wardale and Girdlestone; N&W famously used them in a considerable range of power, although offhand I can only remember Porta using one purely to increase the effective accelerating entrainment length in the front end purely for loading-gage reasons (the others usually being to clear parts of the feedwater heater, as with the Australian Hudsons)  Note that American use of stack extensions, particularly on ATSF, accomplishes the 'same thing' where loading gage permits.

Fascinating in a way that I get all the way here without mentioning the Franklin System at all, let alone the flavors of RC actuation.  Note that one of the issues with OC Franklin, as with Lentz/Lenz before it, involved a certain amount of scam.  The premise was that radial valve gear could be used to drive the System's poppet valves just like piston valves, with shorter cutoff producing different mass flow to the cylinders but with timing precision.  The problem is that with poppet valves, opening them incompletely or slowly doesn't produce good effects; a poppet valve needs to lift cleanly and return sharply without bounce or float, and no SHM valve gear provides this unless the actuating cams are cut with steep profile (in which the necessary modified-trapezoid cam profile is difficult to achieve) and this in turn introduces nightmare-box complexity into the drive mechanism to work.

Meanwhile the RC system can only approximate the continuous cutoff control of Walschaerts or Baker if it uses a continuous-contour cam (which uses spherical followers) and in more sophisticated variants variable actuation or 'variable geometry' on the cam-follower linkage.  To my knowledge no system of fixed cams was particularly successful in practice, and the best of the 'workarounds' was an almost-appalling-to-purists dodge (actually patented!) which used 'wiredrawing' intentionally to give "cutoff" effect with increasing speed ... this was fine for War Department 2-8-0s that could be driven by inexperienced soldiers, but not so good for railroads concerned with best efficiency...

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