FIELD: machine engineering, metallurgical industry branches, namely manufacture and exploitation of heavy rolling mills such as bloomings, slabbings and rough stands of sheet rolling mills. SUBSTANCE: locking device is mounted on lower end of nut and it is open for testing and repairing procedures. Nut includes two portions: stationary one in the form of steel body and portion moving along axis in the form of bronze nut itself. Movable bronze nut has one steel ring with threaded openings for fixing vertical studs in them. Rolling effort is transmitted to locking device from screw through movable bronze nut and stud at locking screw. At working of screw, small overbalancing effort acting upon screw and movable bronze nut may not compress locking device due to resistance of locking mechanisms. Studs, movable bronze nut and screw remain in rest. At biting strip between rolls, large rolling effort Pr exceeds small value of resistance of locking mechanisms and through screw, movable nut and studs compresses locking device. The last locks screw through locking mechanisms. After termination of rolling strip, rolling effort is cancelled and locking mechanisms release screw. EFFECT: enhanced reliability of locking device due to elimination of release of screw of screw-down mechanism at biting and rolling strip between rolls, enhanced efficiency of rolling mill. 4 dwg
