US 4,386,511 A · Method and system for controlling a plate width

Abstract

In a method and a system for controlling a plate width in a hot rolling mill having a front stage including a horizontal roll stand; and a rear stage including a vertical roll stand and a horizontal roll stand, the thickness of a thickened portion of the plate thickened as a result of rolling by the vertical roll stand of the rear stage and the plate thickness at the entrance of the vertical roll stand of the rear stage are determined; the ratio of the thickness of the thickened portion to the plate thickness at the entrance of the rear stage is calculated; the plate width at the exit of the vertical roll stand is determined; the plate width at the exit of the horizontal roll stand of the rear stage is calculated taking account of extension of the plate width as a result of reduction of the thickened portion; and the roll gap of the vertical roll stand of the rear stage is controlled in such a manner as to bring the plate width at the exit of the horizontal roll stand of the rear stage closer to a target value.

Claims13

Dependent claims

A method for controlling a plate width in a hot rolling mill having a front stage including a horizontal roll stand;

and a rear stage following said front stage and including a vertical roll stand and a horizontal roll stand, said method comprising the steps of:
determining the thickness of a thickened portion of the plate thickened as a result of rolling by the vertical roll stand of the rear stage and the plate thickness at the entrance of the vertical roll stand of the rear stage;
calculating the ratio of the thickness of the thickened portion to the plate thickness at the entrance of the rear stage;
determining the plate width at the exit of the vertical roll stand;
calculating, the plate width at the exit of the horizontal roll stand of the rear stage, based at least in part on said calculated ratio of the thicknesses of the plate and said determined plate width;
and controlling the roll gap of the vertical roll stand of the rear stage to bring the plate width at the exit of the horizontal roll stand of the rear stage closer to a target value.

3 more elements

A plate width control system for a hot rolling mill having a front stage including a horizontal roll stand and a rear stage following the front stage and including a vertical roll stand and a horizontal roll stand, comprising thickened portion thickness determining means for determining the thickness of a thickened portion of a plate thickened as a result of rolling by the vertical roll stand of the rear stage;

thickness determining means for determining the plate thickness at the entrance of the vertical roll stand of the rear stage;
ratio determining means for determining the ratio of the thickness of the thickened portion to the plate thickness at the entrance of the vertical roll stand based on the output from said thickened portion thickness determining means and the output from said thickness determining means;
first width determining means for determining the plate width at the exit of the vertical roll stand of the rear stage;
second width determining means for determining the plate width at the exit of the horizontal roll stand of the rear stage based on the output from said ratio determining means and the output from said first width determining means;
roll gap controlling means for calculating the deviation of the plate width at the exit of the horizontal roll stand of the rear stage based on the output from said second width determining means and a target value;
and controlling the roll gap of the vertical roll stand of the rear stage to make the deviation smaller.

3 more elements

Dependencies are inferred from the claim text.

Method and system for controlling a plate width

Life of this patent

Method and system for controlling a plate width

Life of this patent

Abstract

Claims13