User:KVDP/AT freight tram
|
The AT freight tram was inspired by the CarGoTram. Besides being especially built for the delivery of cargo, the CarGoTram also has other features, such as the possibility of also transporting passengers, relative simple technology (original CarGoTram being based on older CKD Tatra trams), ... I think that this tram design, aswell as the entire freight tram concept would be ideally suited for deployment in the developing world. However, one particular problem of the current tram design is the fact that it is only suited to one type of trainrail, ie international gauge, ... (see http://en.wikipedia.org/wiki/Rail_tracks#Gauge ) An update of the CarGoTram design would be a modular CarGoTram design, which allows several track sizes to be driven. This would be needed to allow driving on all types of track, a requirement as there are many developing world countries, and thus use a variety of tracks (atleast that is what I presume, I am unaware of any official publications/figures on this). Having a non rail-specific tram would also allow use to use the tram in any country (regardless on whether its a developing one or not).
2 methods would thus be possible: the 1st method would be to simply design (in 3D) several undercarriages; one for each type of rail (gauge), aswell as rail profile within this gauge (see http://en.wikipedia.org/wiki/Rail_tracks#Rail ). This method could potentially be more suitable for the modification of existing trams/trains. This, as, based on the drawings, it may be more easy to either disassemble existing trains/trams and move the parts unto the new undercarriage OR modify existing train/tram undercarriages so that the wheels come up further or shorter alongside the vehicle. This would probably require the replacement of the axle and wheels, based on the rail gauge and the profile of rail used.
The 2nd method would be to design a new undercarriage in which the wheels can be placed further or shorter alongside the vehicle. However, unlike the former method, this could happen by simply placing a component on the required distance. Thus, the axle itself does not need to be removed. The wheels themselves however still need to be, since there are several rail profiles.
If none of the above methods seem viable or advisable (depends on the rail system employed, see 4 paragraphs below), another method would be to simply opt to change the spacing of the rails themselves. This would mean that either the tram or the trainrail is chosen, and the tram or trainrail spacing is either reduced or enlarged. This would could eliminate the entire problem (in some cases) or only part of it (if the rail profiles are still different). In the second case, perhaps that there are some (light-rail) wheels what allow driving on 2 (not too) different rails ?
For both methods, there would be some disadvantages, such as the fact that the undercarriage will not provide any more space in case a larger gauge track is used (structural risks), and there may even be severe structural risks in case a smaller gauge track is used. Also, I'm not sure how close the tracks are generally layed together, so in some cases, having a larger undercarriage installed may pose risk of collision between 2 trains or trams rolling side by side.
In addition, I'm not certain on whether the propositions would work, since I'm not familiar with train/tram construction, and thus do not know on how the wheels are exactly powered (ie the parts may disallow the moving of the wheels). Especially the second method seems vulnerable to this potential problem. An other thing I'm not sure about is how cost-effective the modifying of older trams/trains exactly is. For example, was the modifying of the CKD Tatra's actually cheaper than building a new train/tram ? I'm btw not aware of the energy consumption of older such vehicles, for example, what would be the benefits of a new (and much lighter ?) vehicles in this regard, and how does this effect this cost-effectiveness ?. Also, I'm not completely aware of how many (old) electric trains still exist in the developing world, and converting non-electric trains/trams would probably be even more expensive.
Finally, for the exact designing and workings of the rail/wheels themselves, I also need the expertise of professionals. The wheel systems are vital ie for taking bends, ... which require the inner wheels and outer wheels to spin at a different speed. As I understand, trains and tram rails have several different methods of supporting the vehicle (see http://en.wikipedia.org/wiki/Difference_between_train_and_tram_rails ). Since in most cases, the amount of train rails will be more extensive than tram rails, we would probably need to opt for train rail systems for the undercarriage. However, the vehicle will still need to be able to also use tram rails. I'm not sure what exact wheel system needs to be used (ie Karlsruhe model, ... http://en.wikipedia.org/wiki/Light_rail#Trams_operating_on_mainline_railways )
[edit] See also
main design to use for the AT freight tram (electric powered version, also the basic version)
profile of the wheels to be used in the AT freight tram (light rail wheels)
using rails within cities + improving old train/tram rails
first draft of the ICE-powered version of the locomotive for the tram; also contains top-view of drive shaft-powered bogie (the unpowered bogie)
first draft of the ICE-EE-powered version of the locomotive for the tram; also contains top-view of EE-powered bogie (the powered bogie)
