Abstract: The invention relates to a press roll (1) comprising a flexible rotating endless-loop blanket (3) of a liquid-impervious material, two disc-shaped roll heads (4, 5), and a clamp element (14) filled with a pressurized medium for clamping the lateral rims (21) of the blanket (3) to the respective ones (4, 5) of the roll heads. The invention is implemented by adapting between the pressurized-medium-filled clamp element (14) and the blanket (3) an annular ring (18) serving to press the rim of the blanket (3) during the pressurization of said clamp element against the inner rim surface (15) of a sector plate (7) and, respectively, serving to contract the clamp element (14) when the pressure of the clamp element (14) is removed or lowered.