Abstract: The invention relates to a method for producing superheated steam in an engine in which highly compressed water is injected into a very hot medium located in the engine, resulting in explosion-like evaporation. Said process is to take place in a specially developed rotational-translational engine in order to utilize a maximum of the thrust of the steam. The engine is to comprise at least two cylinders which have a circular cross-sectional shape (10) and inside which the drive shaft (11) is disposed eccentrically. A rotor (12) that is connected to an element (16) which is inserted through the drive shaft (11) is arranged on the drive shaft. Said element (16) can be moved back and forth in the drive shaft (11) while the ends thereof are fixedly anchored to the rotor (12). The two ends of the rotor (10) are provided with a specially designed triple-roll seal (13) that can lengthen and shorten the rotor (10), which is a requirement when the drive shaft (11) is placed non-axially in a circular cylinder (10).