Plant and method for the production of flat rolled products

Abstract

A rolling plant and method for producing a strip starting from a slab having a certain starting thickness, comprising at least one walking beam heating furnace configured to heat at least the slab to a starting temperature, and a rolling train operatively disposed in line with at least one roughing stand and configured to reduce the thickness of an intermediate rolled product at exit from the roughing stand, until the final strip is obtained; the rolling train comprising at least one pre-finishing stand for obtaining a pre-finished rolled product, and a plurality of finishing stands for obtaining the final strip; the plant comprising load cells directly associated with the pre-finishing stand for detecting the rolling force applied on the pre-finished rolled product, a rapid heating device, interposed between the pre-finishing stand and the finishing stands, for heating the pre-finished rolled product, and a command and control unit connected both to the load cells and also to the rapid heating device and configured at least to selectively activate the latter, at least as a function of the rolling force detected by the load cells.

1 . A rolling plant, for producing a final strip starting from a slab having a certain starting thickness, comprising at least one walking beam heating furnace configured to heat at least said slab to a certain temperature, and a finishing rolling train operatively disposed in line with at least one roughing stand and configured to reduce the thickness of an intermediate rolled product, at exit from said roughing stand, until said final strip is obtained; said finishing rolling train comprising at least one pre-finishing stand able to reduce the thickness of said intermediate rolled product in order to obtain a pre-finished rolled product, and a plurality of finishing stands able to reduce the thickness of said pre-finished rolled product, in order to obtain said final strip, wherein the rolling plant comprises mechanical deformation detection means directly associated at least with the last of said at least one pre-finishing stand and able to detect the rolling force applied on said pre-finished rolled product, a rapid heating device, interposed between said at least one pre-finishing stand and said plurality of finishing stands, for heating said pre-finished rolled product, and a command and control unit connected both to said mechanical deformation detection means and also to said rapid heating device and configured at least to selectively activate said rapid heating device, at least as a function of the rolling force detected by said mechanical deformation detection means, in order to thermally compensate for any cold zones and make the temperature of the bar uniform on its entire length. 
     
     
         2 . The rolling plant as in  claim 1 , wherein said rapid heating device comprises first thermal induction modules able to be selectively activated and regulated by said command and control unit, as a function of the rolling force detected by said mechanical deformation detection means. 
     
     
         3 . The rolling plant as in  claim 1 , wherein said rapid heating device comprises second thermal induction modules able to be selectively activated and regulated by said command and control unit, as a function of a certain target temperature of said intermediate rolled product to be obtained at exit from said heating device. 
     
     
         4 . The rolling plant as in  claim 1 , wherein said first thermal induction modules and said second thermal induction modules are of the transverse flow type. 
     
     
         5 . The rolling plant as in  claim 1 , comprising thermal scanning means disposed at exit from said rapid heating device and configured for the transverse thermal detection of said pre-finished rolled product. 
     
     
         6 . The rolling plant as in  claim 1 , comprising first thermal scanning means disposed upstream of said rapid heating device and configured to thermally scan said prefinished rolled product. 
     
     
         7 . A rolling method, for producing a final strip starting from a slab having a certain starting thickness, in a rolling plant comprising at least one walking beam heating furnace configured to heat at least said slab to a certain starting temperature, and a finishing rolling train disposed operatively in line with at least one roughing stand and configured to reduce the thickness of an intermediate rolled product, at exit from said roughing stand, until said final strip is obtained; said finishing rolling train comprising at least one pre-finishing stand able to reduce the thickness of said intermediate rolled product in order to obtain a pre-finished rolled product, and a plurality of finishing stands able to reduce the thickness of said pre-finished rolled product in order to obtain said final strip, wherein the rolling method comprises at least one detection step in which, by means of mechanical deformation detection means directly associated at least with the last of said at least one pre-finishing stand, the rolling force applied on said pre-finished rolled product is detected, at least one heating step in which, by means of a rapid heating device interposed between said at least one pre-finishing stand and said plurality of finishing stands, said pre-finished rolled product is heated, and a command step in which, by means of a command and control unit connected both to said mechanical deformation detection means and also to said rapid heating device, said rapid heating device is selectively activated at least as a function of said rolling force detected by said mechanical detection means, in order to thermally compensate for any cold zones and make the temperature of the bar uniform on its entire length. 
     
     
         8 . The rolling method as in  claim 7 , wherein in said detection step, said mechanical deformation detection means detect one or more impressions of said pre-finished rolled product to which there corresponds a greater resistance to deformation of the material which involves an increase in the rolling force exerted by said pre-finishing stand. 
     
     
         9 . The rolling method as in  claim 8 , wherein in said rapid heating step, first thermal induction modules of said rapid heating device are selectively activated by said command and control unit to carry out a localized over-heating in correspondence with said impressions of said pre-finished rolled product, at least as a function of the greater resistance to deformation of the material which involves an increase in the rolling force, in order to increase the temperature of said impressions and make the temperature of said pre-finished rolled product uniform on its entire length.