Abstract: A method and hydraulic nut for mounting a hollow article which has a conically shaped opening, such as a conical ring, on a conical shaft. The method comprises the following steps: a) installing the hollow article on the shaft, in order to fit the conically shaped surfaces of the article and the shaft against each other; b) moving the hollow article to a starting position (B), in order to provide an initial press fit; and c) moving the hollow article over a predetermined distance (S.sub.s) from the initial position to an end position (C), in order to provide a final press fit.