The M62 diesel locomotive from Voroshilowgrad, of which several thousand were delivered throughout the Eastern Bloc, was also sold to the Korean State Railways. The variant specially designed for North Korea was designated by the manufacturer as the K62 and was initially delivered 48 times between 1967 and 1969. In North Korea, these locomotives were called “Sinsong”, which roughly means “Nova”. They played an important role in the switch from steam traction to diesel.
In 1970, reverse engineering was used to produce a few copies in-house. Of this Kumsong class, however, probably only a handful of copies were made and engines and other components still had to be procured directly in the Soviet Union. The fact that this project was apparently considered a failure can be seen from the fact that between 1972 and 1974 a further 16 examples were procured from the original manufacturer. Among these were five with a gauge of 1,520 mm, which were used in the border area with the Soviet Union.
Due to the oil shortage in the late 1990s, some examples were converted to electric locomotives by removing the diesel engine and tank and installing the required transformer and pantograph in their place. Since the traction motors were unchanged, the same power was still available as with the diesel locomotives. In reference to the great famine from 1994 to 1998, which was called the “Hard Road” in North Korea, the converted locomotives were given the name “Kanghaenggun”.