For connecting the propeller shaft with the intermediate shaft, a hydraulic coupling flange is used. To fit the flange, high-pressure oil of more than 2000 bar is injected between the muff and the coupling flange by means of the injectors in order to expand the muff. By increasing the pressure by the hydraulic pump, the muff is gradually pushed up the cone. Longitudinal placing of the coupling flange as well as the final push-up of the muff is marked on the shaft and the muff.