Balancing device and rolling mill

The utility model relates to a balancing device which comprises a piston rod, an ejector rod, a gland and a locking piece. A connecting hole is formed in one end of the piston rod, one end of the ejector rod extends into the connecting hole, the gland is detachably connected with the piston rod and can limit the ejector rod in the connecting hole, and the locking piece is detachably connected between the gland and the piston rod so that the gland can be fixed to the piston rod. By arranging the balancing device, the pressing cover limits the ejector rod in the connecting hole, the locking piece fixes the pressing cover to the piston rod, and the pressing cover is detachably connected with the piston rod. Therefore, the reliability of connection between the gland and the piston rod is effectively improved, the gland is prevented from directly falling off after the locking piece is damaged, and the working reliability of the balancing device is ensured. The utility model further relates to a rolling mill. 本实用新型