Metal-strip warped-shape control method, metal-strip manufacturing method, and metal-strip warped-shape control device

Abstract

A metal-strip warped-shape control method for controlling an exit-side warped shape, which is a warped shape of a metal strip downstream of a temper rolling mill in a metal-strip manufacturing facility, the metal-strip manufacturing facility including the temper rolling mill that corrects a shape of the metal strip continuously conveyed, and a warped-shape measurement device that measures a warped shape of the metal strip, the metal-strip warped-shape control method including: calculating an approximation curve for the warped shape of the metal strip using an approximation method selected from parabolic approximation, circular arc approximation, and envelope approximation; and setting operating parameters of the temper rolling mill that can reduce a warp height of the exit-side warped shape based on the approximation curve that is calculated.

1 . A metal-strip warped-shape control method for controlling an exit-side warped shape, which is a warped shape of a metal strip downstream of a temper rolling mill in a metal-strip manufacturing facility, the metal-strip manufacturing facility including the temper rolling mill that corrects a shape of a-the metal strip continuously conveyed, and a warped-shape measurement device that measures a warped shape of the metal strip, the metal-strip warped-shape control method comprising:
 calculating an approximation curve for the warped shape of the metal strip using an approximation method selected from parabolic approximation, circular arc approximation, and envelope approximation; and   setting operating parameters of the temper rolling mill that can reduce a warp height of the exit-side warped shape based on the approximation curve that is calculated.   
     
     
         2 . The metal-strip warped-shape control method according to  claim 1 , wherein:
 the warped-shape measurement device is an entry-side warped-shape measurement device that measures an entry-side warped shape of the metal strip upstream of the temper rolling mill; and   an approximation curve for the entry-side warped shape measured by the entry-side warped-shape measurement device is calculated.   
     
     
         3 . The metal-strip warped-shape control method according to  claim 1 , wherein:
 the warped-shape measurement device is an exit-side warped-shape measurement device that measures the exit-side warped shape of the metal strip downstream of the temper rolling mill; and   an approximation curve for the exit-side warped shape measured by the exit-side warped-shape measurement device is calculated.   
     
     
         4 . The metal-strip warped-shape control method according to  claim 1 , wherein:
 the warped-shape measurement device is an entry-side warped-shape measurement device that measures an entry-side warped shape of the metal strip upstream of the temper rolling mill;   the exit-side warped shape is predicted using a warped-shape prediction model that receives input data including the entry-side warped shape measured by the entry-side warped-shape measurement device and at least one of operating parameters of the temper rolling mill, and outputs the exit-side warped shape that is predicted; and   an approximation curve for the exit-side warped shape that is predicted is calculated.   
     
     
         5 . The metal-strip warped-shape control method according  claim 1 , wherein:
 the metal-strip manufacturing facility is a continuous annealing facility that performs heat treatment on the metal strip; and   the temper rolling mill is disposed downstream of a heating zone for heating the metal strip and a cooling zone for cooling the metal strip heated in the heating zone.   
     
     
         6 . A metal-strip manufacturing method for manufacturing the metal strip with a tensile strength of 980 MPa or higher, the metal-strip manufacturing method comprising:
 utilizing the metal-strip warped-shape control method according to any  claim 1 .   
     
     
         7 . A metal-strip manufacturing method for manufacturing a-the metal strip with a tensile strength of 980 MPa or higher, the metal-strip manufacturing method comprising:
 utilizing the metal-strip warped-shape control method according to claim  5 .   
     
     
         8 . A metal-strip warped-shape control device that controls an exit-side warped shape, which is a warped shape of a metal strip downstream of a temper rolling mill in a metal-strip manufacturing facility that includes the temper rolling mill that corrects a shape of a-the metal strip continuously conveyed, and a warped-shape measurement device that measures a warped shape of the metal strip, the metal-strip warped-shape control device comprising:
 a processor that is configured to:
 acquire the warped shape measured by the warped-shape measurement device; 
 calculate an approximation curve for the warped shape using an approximation method selected from parabolic approximation, circular arc approximation, and envelope approximation; and 
 specify operating parameters of the temper rolling mill so that a warp height of the exit-side warped shape is reduced based on the approximation curve. 
   
     
     
         9 . The metal-strip warped-shape control device according to  claim 8 , wherein:
 the warped-shape measurement device is an entry-side warped-shape measurement device that measures an entry-side warped shape of the metal strip upstream of the temper rolling mill; and   the processor is configured to acquire the entry-side warped shape measured by the entry-side warped-shape measurement device, and calculate an approximation curve for the entry-side warped shape.   
     
     
         10 . The metal-strip warped-shape control device according to  claim 8 , wherein:
 the warped-shape measurement device is an exit-side warped-shape measurement device that measures the exit-side warped shape of the metal strip downstream of the temper rolling mill; and   the processor is configured to acquire the exit-side warped-shape measured by the exit-side warped-shape measurement device, and calculate an approximation curve for the exit-side warped shape.   
     
     
         11 . The metal-strip warped-shape control device according to  claim 8 , wherein:
 the warped-shape measurement device is an entry-side warped-shape measurement device that measures an entry-side warped shape of the metal strip upstream of the temper rolling mill; and   the processor is configured to:
 acquire the entry-side warped shape measured by the entry-side warped-shape measurement device, 
 predict the exit-side warped shape using a warped-shape prediction model that receives input data including the entry-side warped shape and at least one of operating parameters of the temper rolling mill, and output the exit-side warped shape that is predicted, and 
 calculate an approximation curve for the exit-side warped shape that is predicted. 
   
     
     
         12 . The metal-strip warped-shape control device according to  claim 8 , wherein:
 the metal-strip manufacturing facility is a continuous annealing facility that performs heat treatment on the metal strip; and   the temper rolling mill is disposed downstream of a heating zone for heating the metal strip and a cooling zone for cooling the metal strip heated in the heating zone.