Kirchweger condenser
Encyclopedia
The purpose of the Kirchweger condenser (German: Kirchweger-Kondensationseinrichtung or Kirchwegersche Abdampfkondensation) was to preheat feedwater in a steam locomotive
Steam locomotive
A steam locomotive is a railway locomotive that produces its power through a steam engine. These locomotives are fueled by burning some combustible material, usually coal, wood or oil, to produce steam in a boiler, which drives the steam engine...

 using the exhaust steam from the engine. It was invented in 1850 by Heinrich Kirchweger
Heinrich Kirchweger
Johann Gottfried Heinrich Kirchweger was a German railway engineer.Heinrich Kirchweger was born on 12 June 1809 in Stettin, then part of Germany, now Szczecin in Poland. After attending the trade school in Berlin, Kirchweger worked with the industrialist Georg Henschel in Kassel...

. A similar system was developed by Rohrbeck.

Exhaust steam was extracted from the steam chest and fed through a 100 mm diameter pipe under the locomotive to the tender. There the steam was fed directly into the feedwater, which thus heated up to boiling point. The remaining steam was allowed to escape to atmosphere through a second chimney on the tender. The quantity of steam could be regulated using a cock on the tender.

The Rohrbeck system differed in detail from the Kirchweger condenser. Here steam was removed at the blast pipe and led away along the top of the boiler
Boiler
A boiler is a closed vessel in which water or other fluid is heated. The heated or vaporized fluid exits the boiler for use in various processes or heating applications.-Materials:...

. It was regulated by a throttle valve on the blast pipe.

Using such a system fuel savings of between 10 and 20 % were possible depending on the operating conditions, in some circumstances even as much as 30 % could be saved. The Lower Silesian-Märkisch Railway (Niederschlesisch-Märkische Eisenbahn) put this saving at 7.5 % on its locomotives.

However the contamination of boiler feedwater with foreign bodies was a problem. Old sources report erosion of the boiler plates which was caused by fatty acids contained in the lubricant accompanying the exhaust steam. On the other hand the formation of scale in the boiler was delayed because a proportion of the boiler scale constituents had already been left behind in the tender.

On the introduction of injector
Injector
ʎ̩An injector, ejector, steam ejector, steam injector, eductor-jet pump or thermocompressor is a pump-like device that uses the Venturi effect of a converging-diverging nozzle to convert the pressure energy of a motive fluid to velocity energy which creates a low pressure zone that dɯaws in and...

s for boiler feeding the exhaust steam condensers were taken out of use from the 1860s, because injectors could only handle cold water. By about 1880 around 900 German locomotives had been fitted with condensing apparatus.

See also

  • Steam locomotive condensing apparatus
    Steam locomotive condensing apparatus
    A steam locomotive condensing apparatus differs in purpose from the usual closed cycle steam engine condenser, in that its function is primarily either to recover water, or to avoid excessive emissions to the atmosphere, rather than maintaining a vacuum to improve both efficiency and power...

  • Boiler
    Boiler
    A boiler is a closed vessel in which water or other fluid is heated. The heated or vaporized fluid exits the boiler for use in various processes or heating applications.-Materials:...

  • Feedwater heater
    Feedwater heater
    A feedwater heater is a power plant component used to pre-heat water delivered to a steam generating boiler. Preheating the feedwater reduces the irreversibilities involved in steam generation and therefore improves the thermodynamic efficiency of the system...

  • Injector
    Injector
    ʎ̩An injector, ejector, steam ejector, steam injector, eductor-jet pump or thermocompressor is a pump-like device that uses the Venturi effect of a converging-diverging nozzle to convert the pressure energy of a motive fluid to velocity energy which creates a low pressure zone that dɯaws in and...


Source

  • R. von Helmholtz, W. Staby: Die Entwicklung der Lokomotive im Gebiete des Vereins Deutscher Eisenbahnverwaltungen, 1. Band, 1835 - 1880; Verlag von R. Oldenburg, München und Berlin, 1930
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK