Roll stand, rolling system and method for actively damping vibrations in a roll stand

A rolling system (1) for cold rolling metal objects, comprising:

• at least one roll stand (2) and at least one system (3) for actively damping vibrations in the at least one roll stand, wherein the at least one roll stand (2) comprises:
• a rack having a lower working roll (5) and an upper working roll,
• at least one back-up roll (10) for supporting the lower working roll (5),
• a readjusting device (13) positioned on a lower section of the rack beneath the back-up roll for pass-line adjustment and for adjusting height of the at least one back-up roll (10),
• a working roll adjustment unit mounted at a top section of the rack for selectively forming a gap between the lower and upper working rolls,
• at least one actuator (16) for selectively damping vibrations of the roll stand (2), wherein the back-up roll (10) is supported at opposite ends thereof by respective bearing units (11) provided on the rack, the back-up roll (10) being supported on the at least one actuator (16) by one of the bearing units (11), and the at least one actuator (16) being supported below the respective bearing unit (11) directly on the lower section (17) of the rack (8) or indirectly by at least one component (14) of the readjusting device (13),
• at least one vibration sensor arranged on the rack (8) for acquiring the vibrations of the roll stand (2), and
• the at least one system (3) comprising at least one electronic controller in electronic communication with the at least one vibration sensor (18) and with to the at least one actuator (16), wherein vibration signals generated by the at least one vibration sensor (18) are evaluated for generation of control signals, and the at least one electronic controller selectively transmits the control signals to actuate the at least one actuator (16) for introduction of counter-vibrations into the roll stand (2).

A method for actively damping vibrations in a roll stand (2) for cold-rolling a metal product, wherein the vibrations in the roll stand (2) are acquired, and counter-vibrations counteracting the vibrations are generated, the method comprising:

• supporting a lower back-up roll on at least one actuator (16) via at least one bearing unit (11) which supports the lower back-up roll on a rack (8) of the roll stand (2), wherein the at least one actuator (16) is supported directly on a lower section (17) of the rack (8) or indirectly on the lower section of the rack via a readjusting device (13);
• adjusting a height of the lower back-up roll exclusively with the readjusting device for pass line adjustment of the roll stand (2);
• initiating the cold-rolling of the metal product;
• generating the counter-vibrations of at least one actuator (16), and
• introducing the counter-vibrations into the lower back-up roll (10) for supporting a work roll (5) and/or an intermediate roll of the roll stand (2).