Abstract: A calendering machine or a similar machine which has a plurality of treating rollers arranged one above the other and movable in the vertical direction includes a structural unit for rapidly displacing the lowermost roller between its lifted position in which the rollers form treating nips with one another, and a lower position in which the rollers are spaced apart and define gaps between each other. The structural unit is connected to the bearing block of the lowermost roller and incorporates guides, upward movement limiting abutment surfaces for the bearing block, and a hydraulic cylinder-and-piston unit acting on the bearing block from below to displace the bearing block to its lifted position upon introduction of pressurized hydraulic fluid medium into its working chamber, and to permit the bearing to rapidly descend to its lower position upon discharge of the hydraulic fluid medium from its working chamber.