One thing to watch with the New Haven power trucks was the comparatively long rigid wheelbase; another was relatively increased mass 'low down' leading to greater lateral shock on the track structure.
As you read, look up 'monomoteur bogies' and the general practice of modern truck design for ideas, and keep in mind how to adjust the particular system you want to use to the location it's applied (which is one of the potential joys of the Lewty booster).
Control of MU diesels from the cab of a steam locomotive is very old tech at this point. There are a few improvements that could have been made (some of them along the lines of the technology in Valve Pilot devices) that would harmonize the characteristics of the steam locomotive with the diesel consist for train handling. Ask me off-list for some of those details.
In the modern context, this is accomplished very simply by using DPU control from the steam-locomotive cab. This is much less complicated than the older systems, which essentially required a separate control stand (like that in a contemporary diesel equipped for MU) that was not linked to the steam-locomotive throttle and cutoff controls.
I suspect that 'comfort cabs' might have come to be applied to steam locomotives at some point... but even diesels had a long, fairly hard, way to go in the '50s and '60s! My own opinion is that 'cab-forward' designs have been largely eliminated as design desiderata on steam locomotives now that cheap and reliable forward-vision cameras and synthetic-vision systems have evolved. In my opinion the cab environment should actually be 'air-conditioned' and not just have improved heating/loss as on the Porta locomotive designs.
Be careful when using pin-guided trucks under both ends of a steam locomotive. Both the Reading and the Germans came to some grief when trying this approach; the lateral guiding stability compared to a conventional Delta arrangement is much smaller. If you do want to keep an 'Adams bogie' under the bunker, one interesting German approach for bidirectional high-speed design involved using an air cylinder to move the truck pivot point; this or a similar approach might easily be applied to the 8ATT design to make it more stable running bunker-first at even Network-Rail-optimized speed. I don't have the specific technical details for the German 4-6-4T at hand but I suspect I know someone who can give them to you...
Yes it is the Besler steam truck as on the New Haven cars. It would have a auxiliary device. I will have to read! I think this has been mentioned before but David Wardale mentioned using mixed power, one powerful steam locomotive and from it's cab controlling additional diesel locomotives I think Having a locomotive that has this capability and all of the creature comforts of a diesel locomotive would be a good idea. If your going to do this today I would put this locomotive http://www.martynbane.co.uk/modernsteam/ldp/lvm/lvm801.htm.htm on this chasey http://www.dlm-ag.ch/en/locomotives/85-projekte-normalspur?format=pdf with side tanks but that would be this http://5at.co.uk/index.php/the-locomotive/options/8att-2-8-4t.html with a water canteen.
NorthWestOvermod, are you referencing the battery storage system?
No, this is the system where the current generated by the traction motors in 'dynamic' is directed to heating elements in circulating tubes, inside tor connected to the convection section of the boiler. Think of grids designed to transfer heat to water instead of air...
Works just like dynamic from the braking perspective, doesn't require expensive and heavy battery pack to convert the power into a form that can be used later for useful traction, etc. The catch, as I said, is that it develops peak pressure and temperature progressively as you go downhill (and don't need to be working steam), so some part of the boiler structure has to be relatively oversized, or made intentionally much stronger than nominal boiler pressure would require. In the system as originally designed, there were no supplemental DB grids for those times you'd have to keep using dynamic with the boilier actively popping off -- the effective water rate being a relatively expensive alternative to air cooling at that point...
The system can be modified somewhat to include energy storage, to assist with feedwater heating, and even by having the elements in the circulation path from an injector. (You can't heat the water up to the point it goes through the check valve into the boiler, but once it's inside you can at least theoretically heat it enough to balance the drop in steam pressure resulting from heavy injector use... so recovery at the top of a steep grade could be made with a bit less thermal cycling.
In my opinion it should be possible to incorporate some elements of this type into the tubes and manifolds of a Cunningham circulator, and crank up the circulating volume to the optimal rating of the jet pump.
Overmod, are you referencing the battery storage system?
woups duplicate post! :)
Is this the Besler steam truck as on the New Haven cars, with the longitudinal cylinders? Or is this referencing the engine out of the 'truck' project being researched in Germany during the '30s with Doble... which was an actual truck (aka 'lorry' in British English) for road use?
Be careful using some of Tom's approaches. There are some thermodynamic issues with power density in that regenerative braking scheme, and a boiler near popping off is NOT really the place you want to start dumping dynamic-braking heat. We've discussed some better ways to use the traction-motor 'braking' power on those 'carrying axles'...
Thank you I am going with the Besler steam truck instead of the Lewty booster but the locomotive's guide wheels and the tender will still have the trackshan motors and heat the boiler. This is a real technology that belongs to T.W. Blasingame, Inc. Go to http://www.trainweb.org/tusp/news/Steam%20Page%20Release%206-13-2005.pdf for the PDF.
Some cool stuff here. Let's encourage him.
I did not find the patent reference for the electric booster in the first references. Can you provide the patent numbers?
Be advised that historically DC traction motors are not happy under an ashpan. They don't like the heat soak or the ash/blowdown leakage, and coal dust is conducive to flashovers and other problems. And it is difficult to rig cooling-air ducts with appropriate properties as well as the necessary 'swing' to work in that area. I think you would be better served to adopt Porta's version of the Lewty booster...
One little note: the Besler engines (as designed for the B&O W1) were not V2's; they were parallel-cylinder. (The V2s were on the German motor locomotives.) I'm not sure about how viable those motors would be in practical road service (see previous posts in these threads on the general subject!)
There is a great wealth of historical precedent for "MU control" of steam locomotives from the period between 1920 and 1928, in the heyday of automatic train control. (Note that ATC penalty braking on steam locomotives involved modulation of throttle and brake to work). All the technical files for Frank Sprague's train-control company are preserved at the New York Public Library.
Meanwhile, a practical device for automatic cutoff control based on back-pressure was designed and demonstrated in the early Twenties. This is the other piece of the puzzle making full autonomic train control a possibility. Now concentrate on slip control.
(All this involves the use of relatively contemporary technology, rather than modern technology and design approaches. Note that much of the automatic control in the Cook '219 patent was presaged by Doble's and Besler's work on steam automobiles.
I am not a very strong proponent of MUing steam locomotives together - -there are too many complexities and not enough bottom-line financial reward, and in the contemporary model for maintaining steam power much of the special control systems would work no better than the butterfly valves used on the Q2s. Plenty of people disagree with my assessment. I encourage them to make themselves right.
Welcome to the forums -- and keep commenting!
Steam that could have been
This once was Juniatha's thread What steam we haven't seen - relaunch
This is like what steam we haven't seen but allows unconventionals
This is a historical thread for new steam locomotives post on Extreem steam III for new steam locomotives.
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