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26-434: The P 6 was conceived as a so-called universal locomotive. The first vehicle was manufactured in 1902 at Düsseldorf by the firm of Hohenzollern . This engine has a number of features that are characteristic of its designer, Robert Garbe : a narrow chimney located well forward and the unusual position of the boiler . As a result, and in spite of the relatively small, 1,600 mm (62.99 in) diameter, driving wheels (on

52-419: A compound steam engine with an additional low pressure stage or even a low speed turbine. Waste heat on modern steam plants is often recovered using heat exchangers. However, condensing locomotives do not have this benefit due to the waste heat being expelled to the surrounding air and not being recovered, and therefore none of the energy in the waste steam is recovered to do mechanical work. In many conditions

78-407: A full-length roof and this was surmounted by a nest of air-cooled copper tubes in which the exhaust steam was condensed. Kitson & Company made many engines of this type. The system was satisfactory for tram engines (which were very low-powered) but would not have worked for larger railway locomotives. Generally this was a more sophisticated installation that used forced air cooling to condense

104-419: A high volume gas to a low volume liquid causes a significant pressure drop at the exhaust, which usually would add additional power in most steam engines. Whilst more power is potentially available by expanding down to a vacuum, the power output is actually greatly reduced compared to a conventional steam locomotive on account of the lower air flow through the firebox, as there is now no waste steam to eject into

130-493: Is then liquified by pressure, using a specially-designed boiler feed pump. A fuel saving of nearly 30% (compared with exhausting to the atmosphere) was claimed for the Anderson system but this seems paradoxical. One would expect a higher fuel consumption because of the power required to compress the aerosol. The reason this is possible is due to Carnot's theorem , which states that pumping heat requires less energy than producing

156-702: The Deutsche Bundesbahn and the Reichsbahn . The locomotives taken over by the Polish State Railways (PKP) were given the designation Oi1 . One of them has been preserved and can be viewed in the Warsaw Railway Museum . The engines were equipped with Prussian tenders of class pr 2'2' T 16. Hohenzollern Locomotive Works The Hohenzollern Locomotive Works (Aktiengesellschaft für Lokomotivbau Hohenzollern)

182-718: The First World War as reparations : 44 to Poland (PKP Oi1), 24 to Belgium, 19 to France (16 to the Nord (3.1551–3.1566), 3 to Alsace-Lorraine), 9 to Italy (FS 626), 6 to Lithuania, 4 to Latvia and 4 to the Territory of the Saar Basin (2101–2104). 163 locomotives were taken over by the Deutsche Reichsbahn as DRG Class 37.0-1 , where they were allocated the running numbers 37 001 to 37 163. In 1935

208-546: The Metropolitan Railway to allow their locomotives to work the tunnels of the London Underground . This system was devised by Daniel Gooch and developed by Beyer, Peacock & Company . Steam is diverted from the exhaust steam pipes into the water tanks via condensing pipes within the same tanks. The water in the tanks could quickly heat up near boiling point , reducing the condensing effect on

234-846: The German locomotive building industry around 1929 the works was closed in November 1929. The Hohenzollern AG had hoped in vain for follow-on orders for the DRG Class 80 from the Deutsche Reichsbahn-Gesellschaft (DRG). Locomotive number 80 030 in the Bochum-Dahlhausen Railway Museum was one of the last built by the Lokomotivbau Hohenzollern and is preserved today in photograph-grey livery. The last locomotives left

260-517: The Titanic and its sister ships. This is several times the weight of an entire locomotive, and so is clearly not feasible as a form of waste steam recovery for locomotives. A drawback of condensing the exhaust steam is that it is no longer available to draw the fire, by use of the blastpipe . The draught must thus be generated instead by a steam-driven fan. Where possible, this has been arranged to use exhaust steam, although in some cases live steam

286-413: The atmosphere, rather than maintaining a vacuum to improve both efficiency and power . Unlike the surface condenser often used on a steam turbine or marine steam engine , the condensing apparatus on a steam locomotive does not normally increase the power output, rather it may decrease considerably due to a reduction of airflow to the firebox that heats the steam boiler. Condensing the steam from

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312-412: The condensate back into the boiler is likely to reduce the power output over what was achievable from simply venting to atmosphere . These restrictions do not apply to marine or stationary steam engines due to not having size or weight restrictions. Ships often had massive waste steam recovery systems, such as the 400 ton waste steam turbine used to recover very low 6 psi (41 kPa) waste steam on

338-470: The exhaust steam is blown into an air-cooled radiator, similar to that used for the cooling system of an internal combustion engine . This system was used on small tram engines (where the condenser was mounted on the roof) and on large tender engines (where the condenser was mounted in the tender). The Anderson condensing system uses an air-cooled condenser but the steam is only partially condensed to form an aerosol of water droplets in steam. This aerosol

364-437: The exhaust steam that would normally be used to produce a draft for the firebox , and routes it through a heat exchanger , into the boiler water tanks. Installations vary depending on the purpose, design and the type of locomotive to which it is fitted. It differs from the usual closed cycle condensing steam engine , in that the function of the condenser is primarily either to recover water, or to avoid excessive emissions to

390-638: The exhaust steam. It was not unknown for the tanks to be emptied and refilled with cold water on a regular basis. Ordinary injectors will not work with hot water (until hot-water injectors were developed) so condensing locomotives were usually fitted with axle -driven boiler feedwater pumps . When not working in tunnels, the steam was directed to the blast pipe and up the chimney in the usual way. In Britain , locomotives working on roadside steam tramways were required by law to have condensers. Water tank condensers (as above) were sometimes used but air-condensers were more common. A steam tram engine usually had

416-506: The factory in September 1929; it was immediately torn down. Hohenzollern built a large number of fireless locomotives, including some articulated fireless locomotives with a cab at each end. Hohenzollern's fireless locomotives were unusual in having inside cylinders. The German term for fireless steam locomotive is Dampfspeicherlokomotive , meaning steam storage locomotive. Each locomotive had two 2-axle bogies. On no. 1685 only one axle

442-425: The firebox exhaust in order to pull more air into the firebox air intake. In order to produce similar power, air to the firebox must be provided by a steam driven or mechanically driven fan. This often cancels out any improvement in efficiency. The temperature of the exhaust steam is greater than typical stationary or ship-based steam plant of similar power due to having fewer waste recovery stages, as ships often have

468-582: The four Saar locomotives were incorporated into the DRG fleet as 37 164 to 37 167. The locomotives with numbers 37 201–206 were, by contrast, G 6 and P 6 class engines respectively of Lübeck-Büchen Railway (LBE), that had a different design from the Prussian locomotives. The Prussian P 6s were retired by about 1950. The few engines left after the Second World War were no longer employed by

494-524: The heat itself. A similar effect known as Vapor-compression desalination was later used for desalination of water. Instead of returning the condensate water to the boiler, the hot compressed condensate is passed through a heat exchanger to return heat to the boiler, then released as clean drinking water. It is one of the most efficient processes used to desalinate water. There are two usual reasons for fitting condensing equipment - reducing exhaust emissions and increasing range. Originally developed for

520-430: The prototype they were only 1,500 mm or 59.06 in), the locomotives were authorised to travel at up to 90 km/h (56 mph), a speed which could not be attained in practice due to its poor riding qualities. The smokebox superheater installed on the first machines was soon replaced by a smoke tube superheater . In all, 275 engines of this class were built up to 1910. 110 examples had to be handed over after

546-648: The same time, Russian State Railways also took delivery of a 1,200 horsepower (890 kW) diesel-electric locomotive , class E el-2 , designed in Russia by Professor Lomonosov . Work on this locomotive was started by Hohenzollern, but for political reasons, it was later transferred to Maschinenfabrik Esslingen . Condensing steam locomotive A condensing steam locomotive is a type of locomotive designed to recover exhaust steam, either in order to improve range between taking on boiler water , or to reduce emission of steam inside enclosed spaces. The apparatus takes

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572-400: The temperature gradient is often much worse due to using air instead of having an abundant source of cooling water as naval or stationary steam power plants have. The Anderson condensing system significantly reduces these losses by only partially cooling the waste steam before compressing it into condensate, then pumping the high temperature condensate back into the boiler in order to recover

598-436: The unused waste heat. This greatly reduces energy waste . Because of the relatively high temperature in a locomotive condenser and the rejection of the heat to the air, the potential improvement in thermal efficiency expected from including the condenser in the cycle is not usually realised within the space constraints of a typical locomotive. Indeed, losses due to viscous friction in the condenser piping, and having to pump

624-464: Was a German locomotive -building company which operated from 1872 to 1929. The Hohenzollern works was a manufacturer of standard gauge engines and about 400 fireless locomotives as well as diesel locomotives of various rail gauges . The company was founded on 8 June 1872 in Grafenberg near Düsseldorf . The firm produced around 4,600 locomotives. After the increasingly critical situation in

650-558: Was powered, but on the others, two axles were powered. For an explanation of wheel arrangements see: AAR wheel arrangement . Nos. 1685 and 2107 (both designed for use in mines) had air-cooled condensers to condense the exhaust steam. Hohenzollern supplied a 1,200 horsepower (890  kW ) diesel-mechanical locomotive to the Russian State Railways in the 1920s. This had a constant-mesh gearbox with an individual electromagnetic clutch to engage each gear. Around

676-406: Was required, with extra steam and thus fuel consumption. Steam locomotive condensers may be water-cooled or air-cooled. Here, the exhaust steam is blown into cold water in the locomotive's water tanks. A non-return system must be fitted, to prevent water from the tanks being drawn into the cylinders when the steam is shut off. This system was mainly used for locomotives working in tunnels. Here,

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