Württemberg K

In order to be able to haul the ever heavier freight trains on the Württemberg network without double-heading, the class K with a 2-12-0 wheel arrangement of was procured from Maschinenfabrik Esslingen from 1917 onwards. They were the only twelve-coupled locomotives in Germany. The reason for the large number of wheel sets was that the axle load was limited to 16 tonnes and it would therefore not have been possible to build a sufficiently powerful locomotive with an 0-10-0 or 2-10-0 wheel arrangement.

In order to enable good running in curves, the first and sixth driving axles were designed with lateral movement according to the Gölsdorf system and the wheel flanges of the third and fourth wheel sets were thinner by 15 mm. In addition, the leading axle could be adjusted radially and moved laterally. The locomotives were powered by a four-cylinder compound engine with power transmission to two axles according to de Glehn. The inside high-pressure cylinders acted on the third driving axle and the outside low-pressure cylinders on the fourth. The second driving axle also had to be cranked so that the connecting rods of the high-pressure cylinders had enough space. In addition to the Württemberg tenders, Prussian tenders, which had a larger capacity, were also used later.

The first production lot consisted of three locomotives, construction of which began in 1917 and could be delivered in January 1918. A further twelve locomotives were delivered in 1919. Since there was still a need after the founding of the Reichsbahn, another 29 were built in 1923 and 1924, bringing the total to 44. The locomotives were mainly used on the Geislinger Steige and the Black Forest Railway, where they proved themselves extremely well. In the lowlands, however, they used more steam than lighter locomotives, which also had sufficient power there. After the Geislinger Steige was electrified in 1933, the locomotives, now known as class 59, were distributed to other mountain lines in Württemberg. After 1938, when Austria was annexed by the German Reich, a large part of the locomotives came there and were used, for example, on the Semmering Railway.

This was the reason why 30 class K locomotives remained in Austria after the end of the war. Some had to be handed over to either the Soviet Union or Hungary as reparations, others were returned to the Bundesbahn. The remaining four were designated class 659 and retired between 1951 and 1957.

The Bundesbahn also didn't find much use for the class 59, since the standard and war locomotives constituted to thousands of equally powerful freight locomotives available. In particular, the class 44, with only five coupled axles but a greater axle load, was able to generate even more power. Thus, most of the locomotives which returned to West Germany from Austria or Hungary were immediately scrapped and the rest all disappeared by 1953 at the latest.