Mass flow regulation in roller devices

A method for controlling a roller line, which has one or more roller stands each with two working rollers, which form a roller gap, through which a roller band is transportable, wherein one or both working rollers can shift relative to the other, so that the roller gap is adjustable, wherein the method comprises controlling the roller line by performing the steps of:

• determining a reference speed, which is a parameter for controlling the roller line;
• measuring a speed of the roller band before an inlet into a first roller gap;
• measuring a thickness of the roller band before the inlet into the first roller gap;
• and
• adjusting one or more roller gaps of one or more roller stands in the roller line on the basis of the measured speed and the thickness before the inlet into the first roller gap as well as the reference speed,
• wherein the controlling of the roller line is carried out without taking into account any measured or calculated outlet side band speed at a last roller stand of the one or more roller stands, and further comprising:
• determining a reference band thickness, which is a parameter for controlling the roller line, and before the adjusting of the one or more roller gaps, computing a thickness deviation of the roller band as follows:
• h
• iDevCalc
• ⁡
• (
• t
• )
• =
• h
• iTrk
• -
• 1
• ⁡
• (
• t
• )
• *
• v
• i
• -
• 1
• ⁡
• (
• t
• )
• v
• iR
• ⁡
• (
• t
• )
• -
• h
• iR
• wherein:
• hiDevCalc(t)=the thickness deviation of the roller band,
• hiTrk−1(t)=the thickness at an inlet of any roller stand,
• vi−1(t)=the measured speed,
• viR(t)=the reference speed, and
• hiR=the reference band thickness.