Giesl ejector

A Giesl ejector is a suction draught system for steam locomotives that works on the same principle as a feedwater pump. This ejector (German: Ejektor, Flachschornstein or Quetschesse) was invented in 1951 by the Austrian engineer, Dr. Adolph Giesl-Gieslingen. The Giesl ejector ensures improved suction draught and a correspondingly better use of energy. The existing blastpipe in a locomotive is replaced by several, small, fan-shaped, diverging blast pipes, from which the diffuser gets its flat, long, drawn-out shape.

Giesl claimed that his ejector enabled a saving in coal of between 6 and 12% – although in practice the maximum saving was more like 8% – and an increase in power of up to 20%. Many railway administrations converted their steam engines to Giesl ejectors, including the ÖBB, ČSD and Deutsche Reichsbahn (DR) in East Germany, as well as railway companies in Africa, China and Japan. The licence fees were not paid in every case, it being said that often they almost cancelled out the saving in coal. In the DR it was assessed that the Giesl ejectors would pay for themselves within a year, as a result of which they converted over 500 locomotives; primarily the Classes 38.10, 50, 52 and 65.10.

In 1958, Dr Giesl-Gieslingen approached British Railways to offer a free trial of the ejector. When this offer was turned down, the inventor made the same offer to the preserved Talyllyn Railway in Wales, and locomotive No. 4, Edward Thomas was fitted with one. Although a coal saving of 40% was officially announced at the time, this has since been disputed by the railway's chief engineer. The ejector was removed in 1969, and no difference in coal consumption was found. The ejector is now on display in the Narrow Gauge Railway Museum at Tywyn.

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