Kirchweger condensation device
The Kirchweger condensation device (also Kirchweger exhaust steam condensation ) was used to preheat the feed water in steam locomotives using the steam from the steam engine. It was invented by Heinrich Kirchweger around 1850 . A similar device came from Rohrbeck .
The exhaust steam extracted from the valve body was conducted under the locomotive to the tender via a pipe approximately 100 mm thick. There the exhaust steam was fed directly into the feed water, which was heated to boiling. The remaining exhaust steam was able to escape into the open through a second chimney on the tender. The amount of steam could be regulated via a tap on the tender.
The Rohrbeck device differed in details from the Kirchweger design. Here the steam was first removed from the blowpipe and passed above the boiler. Here the regulation was carried out by a throttle valve on the blowpipe.
The possible fuel savings could be 10 to 20%, in individual cases up to 30%, depending on the operating conditions. The Lower Silesian-Märkische Eisenbahn gave this value for their locomotives as 7.5%.
The enrichment of the boiler feed water with foreign substances was problematic. In old sources there are reports of corrosion on the boiler plates, which were caused by the fatty acids in the lubricants contained in the exhaust steam. On the other hand, the formation of scale in the boiler was slowed down, since some of the scale formers were eliminated in the tender.
With the introduction of the injector to feed the boiler, exhaust steam condensation came out of use again in the 1860s, since injectors only work with cold water for physical reasons. By around 1880, around 900 German locomotives had been equipped with condensation devices.
literature
- R. von Helmholtz, W. Staby: The development of the locomotive in the area of the Association of German Railway Administrations , 1st volume, 1835-1880. Published by R. Oldenburg, Munich / Berlin 1930