Abstract: The machine comprises a frame, a first roller rotatably supported by the frame and a second roller rotatably supported by the frame and disposed below the first roller to cooperate therewith. A gear is secured to the first roller to be rotatable therewith meshes with at least two pinions, each mounted on the shaft of a respective pressure-fluid operable motor. A pump is connected to each of the pressure-fluid operable motors to supply pressure-fluid in common to the motors so that all the pressure-fluid operable motors operate in synchronism.

Abstract: The machine comprises a frame, a pair of nip rollers, two side-rollers disposed on respectively opposite sides of the nip rollers, and four pressure fluid operable devices each displaceably supporting a respective end portion of one of the side-rollers. Each pressure fluid operable device comprises a cylinder and a piston provided with a rod extending through one end portion of the respective cylinder to bear against the frame, the respective other end portion of each cylinder defining a housing provided with bearing means for the respective side-roller end portions and each cylinder being displaceably mounted in guide means.