Abstract: A device including unpiling apparatus of the gripper type, each gripper including a pick-up beak, the fixed plate of the gripper being rigid with a carriage movable on a horizontal guide, this carriage being coupled to the piston rod of a fixed fluid-operated cylinder and adapted to transfer the sheet or web picked up by the beak from one pick-up station to the treatment station. It further includes apparatus for causing the pick-up beak to grip the web by turns in a first and a second positions, the second gripping position causing the picked-up web to be turned upside down.