After World War II, the production of iron ore in Kiruna and Malmberget increased dramatically and the train length was increased, with the consequence that each train needed more propulsion.

One engine, 4.2046, is buried under gravel and soil below the railway near Katterat, where it ended up at a derailment in 1959.

Heavy rainfall had caused flooding that damaged the line in Sørddalen.

4.2046 was hauling an inspection train when the embankment that carried the track failed and the engine tipped over.

Usable parts were stripped from the engine before it was buried when the embankment was rebuilt.