Mill vibration control apparatus and method

Apparatus and method for reducing vibration in a mill stand. The apparatus comprises a roll ( 4 ) positioned upstream or downstream of the mill stand ( 1 ) and over which the strip material ( 2 ) being rolled is passed. The vibration control apparatus comprises an inertia element in the form of a flywheel ( 7 ) connected to the roll ( 4 ) by a stiffness element in the form of a compliant shaft ( 6 ). The components ( 6 ) and ( 7 ) form a mechanical system which can be tuned in such a way as to introduce a speed fluctuation at the roll ( 4 ) which exactly matches the speed fluctuation of the strip material as it enters the roll bite. Both the inertia element ( 7 ) and stiffness element ( 6 ) can take other forms: for example, the stiffness element could be a flexible drive belt or belts; the inertia element could be a shaft about which the roll ( 4 ) rotates, via a stiffness element.