Patent ID: 11858019
Assignee: NIPPON STEEL CORPORATION
Field: Machine tools (Mechanical engineering)
Classification: CPC B | IPC B

Claim 5:
6. A control device which adjusts a screw-down position of a rolling mill in a slab manufacturing facility which includes: a twin-drum type continuous casting device configured to cast a slab by solidifying a molten metal using a pair of rotating casting drums; and a rolling mill configured to roll the cast slab using a pair of work rolls, comprising:
a plate thickness calculator which calculates estimated plate thicknesses at both of end portions of the slab in a width direction from Expression 1:, (
      
       estimated
       ⁢
          
       plate
       ⁢
          
       thickness
       ⁢
          
       on
       ⁢
          
       entry
       ⁢
          
       side
       ⁢
          
       of
       ⁢
          
       rolling
       ⁢
          
       mill
      
      )
     
     =
    
   
   
    
     Expression
     ⁢
        
     1
    
   
  
 

 
  
   (
   
    screw
    -
    down
    ⁢
       
    position
    ⁢
       
    of
    ⁢
       
    casting
    ⁢
       
    cylinder
   
   )
  
   
  +
 

 
  
   (
   
    elastic
    ⁢
       
    deformation
    ⁢
       
    of
    ⁢
       
    casting
    ⁢
       
    drum
   
   )
  
   
  +
 

 
  
   (
   
    casting
    ⁢
       
    drum
    ⁢
       
    housing
    ⁢
    
       ⁠
      
    
    ⁢
    screw
    -
    down
    ⁢
       
    system
    ⁢
       
    deformation
   
   )
  
   
  +
 

 
  
   (
   
    drum
    ⁢
       
    profile
    ⁢
       
    of
    ⁢
       
    casting
    ⁢
       
    drum
   
   )
  
   
  -
 

 
   
  
   (
   
    elastic
    ⁢
       
    deformation
    ⁢
       
    of
    ⁢
       
    casting
    ⁢
       
    drum
    ⁢
       
    at
    ⁢
       
    the
    ⁢
       
    time
    ⁢
       
    of
    ⁢
       
    screw
    -
    down
   
  
 

 
  
      
   
    position
    ⁢
       
    zero
    -
    point
    ⁢
       
    adjustment
   
   )
  
   
 

using casting drum housing screw-down system deformation characteristics acquired prior to the start of slab casting indicating deformation characteristics of housings configured to support the casting drums and deformation characteristics of a screw-down system configured to screw down the casting drums;
a ratio calculator which obtains an entry-side wedge ratio indicating a ratio of an entry-side wedge which is a difference between plate thicknesses of both of the end portions on an entry side of the rolling mill to an entry-side plate thickness of the slab using the estimated plate thicknesses, and
which obtains an exit-side wedge ratio indicating a ratio of an exit-side wedge which is a difference between plate thicknesses at both of the end portions on an exit side of the rolling mill to an exit-side plate thickness of the slab; and
a controller which adjusts a screw-down position of the rolling mill so that a difference between the entry-side wedge ratio and the exit-side wedge ratio is within a prescribed range.