bearing elements 13 c 13 d acting transversely in opposite directions to the nip plane a a with the main bearing elements 13 a 13 b the position of the shell 12 is adjusted relative to the nip plane a a with the side bearing elements 13 c 13 d the shell 12 is kept in right position transversely to the nip plane a a with the main bearing elements 13 a 13 b and the side bearing elements 13 c 13 d also the oscillations are attenuated in the direction of the nip plane a a and respectively in the transverse direction a first main bearing element 13 a acting in the nip direction in the nip plane a a is a so called guiding bearing element and a second main bearing element 13 b acting in the opposite direction is a so called slave bearing element respectively a first side bearing element 13 c acting in transverse direction is a guiding bearing element and a second side bearing element 13 d acting in opposite direction is a slave bearing element the supply of pressure medium to the bearing elements 13 a 13 b 13 c 13 d is.