The centering mechanism is intended for rotary columns for capping of containers with various shape and without neck. There are one or more centering mechanisms (11) in the rotary column, as each one of them has a support platform (16) on which there is a container (10), which is to be capped. The centering axis (13) is irremovably attached underneath and to the support platform, and is mounted to the guiding member (15) via bearings. In the guiding member (15) and centering axis (13), an opening has been made where the bearing axis (20) of the drive bearing (21) is located. The bearing axis (20) is irremovably fastened to the guiding member (15), to which a movable platform (22) is irremovably mounted. The changeable holders (23) are fastened to the movable platform (22) by bolt connection, and are passing through openings, made in the support platform (16). The support platform (16) of the centering mechanism (13) is changeable, as the shape and size of the support platform (16) are defined by the shape and size of the container being capped (10).