Method of avoiding run out on a machine for casting between rolls

A method of avoiding run out on a machine supported by a housing frame for casting a strip between two rolls, at least one of which rolls is driven by an electric or hydraulic motor, comprising the steps of:

• measuring at a constant initial rotary speed of at least one of the rolls a parameter P selected from the group consisting of electrical intensity for an electric motor, fluid pressure for a hydraulic motor, torque exerted on at least one of the rolls to advance the strip and force exerted by the strip on at least one of the rolls or on the housing frame;
• reading initial values for P=P.sub.0 at at least 20 equidistant positions of the roll during a revolution of the roll;
• determining the values of P read at the same position of the roll during a given revolution n-1 and the subsequent revolution n;
• reducing the rotary speed of the roll when the value of P diminishes by at least 2% compared with P.sub.0 for three successive positions between revolution n-1 and revolution n;
• stopping the reduction in speed when P>P.sub.0 is measured;
• increasing the rotary speed of the roll when the difference between P and P.sub.0 remains constant between a revolution n-1 and a revolution n;
• and
• continuing said increasing until the initial rotary speed is attained, unless another diminution of P by at least 2% is measured.