a roll for the preparation or treatment of fiber webs includes a fixed central axis , a roll shell adapted to rotate around the fixed axis and a first chamber disposed between the central axis and the rotatable roll shell . the first chamber is filled with liquid which can transfer a hydraulic supporting force from the central axis to the roll shell . the roll includes a second chamber that is partially filled with air and partially filled with a liquid . several narrow capillary lines connect the first and second chambers . the capillary characteristic of the capillary lines ranges between about 2 . 5 × 10 7 m - 2 and about 2 . 5 × 10 8 m 2 .