In the twenties, the ELNA (Engerer Lokomotiv-Normen-Ausschuß - Special locomotive standards committee) designed a range of standard locomotives to be built for private and light railways. The ELNA 6 was the heaviest of these types and had the wheel arrangement 0-8-0T. With a top speed of 40 km/h, it was intended for all kinds of traffic on secondary lines and also for shunting. With a wheelbase of less than 4.5 meters, it did not need axles with lateral play.
Between 1922 and 1946, a total of 116 were built by different manufacturers since they were included in the war locomotive program as KDL 4. In this context, also Schneider of Le Creusot in France had to manufacture these and also continued production after the war for a total of 67. Thanks to the liberation of France, all 67 could stay in the country, came to the SNCF and were designated 040 TX.
In Germany, there was a total of four different variants. The standard type was offered in a cheaper saturated and a more powerful superheated variant, called ELNA 6 N and ELNA 6 H. Krauss of Munich could realize a cheaper production by using tooling already existing for other locomotives, so the seven locomotives resembled some other types which were in use in Bavaria. They also had larger side water tanks instead of the well tanks of the standard variant and were heavier. Additionally, seven of the locomotives produced by Henschel were of an augmented type that had a higher boiler pressure, larger cylinders and a larger superheater. These also had side tanks and were even heavier than the Krauss type. Later some got wheels with a diameter of 1.200 instead of 1.100 mm.
As the customers were private and light railways, most of them only got one to three locomotives. The largest customer was the Halle-Hettstedt Railway Company that got seven of which four came from Krauss. After the war, the West German locomotives remained in private ownership, while the East German ones were taken over by the Reichsbahn. Most were put into class 9264, but three with a counter-pressure brake became class 9229. Today three are preserved.