Non-stop steam locomotives were used where fire and smoke were undesirable — in tunnels, in fire-hazardous industries (paper mills, oil refineries), etc. Such a locomotive did not have a coal / oil furnace, but instead was equipped with a heat-insulated boiler battery.
(from the Petersburg Museum of Railways of Russia )Before the start of operation of the bestopochny steam locomotive, it was filled with water at 60-70%, and then steam was supplied to it from a stationary boiler installation through a special pipe.
In front, it must be assumed, just a valve for refueling:
Steam heated the water, and when its temperature reached the boiling point, i.e. the pressure in the boiler became equal to the pressure of the stationary boiler, the engine was ready for action. When steam was introduced into the cylinders, the vapor pressure in the boiler gradually decreased, and the water continued to boil; with decreasing pressure, the boiling point of water also decreased.
Non-locomotives could work from refueling to refueling for 4-6 hours.
To increase the battery life went on different tricks. For example, simultaneously with charging with steam, a battery-boiler was filled with compressed air special tanks for the operation of auxiliary units of a locomotive.
A more interesting way to extend the work came up in the XIX century. The steam spent in the cylinders was not released into the atmosphere, but condensed in a separate tank that surrounded the boiler. The caustic soda was in the tank (it is sodium hydroxide, caustic soda, NaOH).
It is known that the process of dissolution of certain substances in water is accompanied by the release of heat; caustic soda is one of those. The heat of dissolution was transferred to the water in the boiler and increased the mileage of the locomotive without recharging.
Honigmann's bestopochny locomotive presumably for the Gotthard Tunnel (1885). Blue - water in the boiler, pink - a solution of caustic soda:
Steam trams worked in Aachen
and minneapolis
After use, the soda solution was restored to its initial concentration by boiling or passing steam through it.
The calorific value of caustic soda is not very high, but noticeable: 30 kg of dry sodium hydroxide are equivalent to 1 liter of gasoline (actually less - depending on the solution concentration, temperature, etc.). They write that the Akhen tram carried on itself about a ton of soda.
The system was predicted a great future, in particular, on submarines. After all, there are substances that, when mixed with water, emit even more heat - sulfuric acid, for example. However, the danger of having several tons of hot alkali / acid side by side outweighed the rest. Did not take off.
Sources: Rakov R.A. "Locomotives of domestic railways" &
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