Patent ID: 11919062
Assignee: POSCO CO., LTD
Field: nan (nan)
Classification: CPC nan | IPC B  C

Claim 11:
12. The method of claim 1, wherein the heating is performed to a condition that a value of Relational Expression 2 below is 2 or more,, ∑
   
    n
    =
    1
   
   x
  
   
  
   
    [
    
     
      {
      
       
        (
        
         
          T
          n
         
         -
         870
        
        )
       
       ×
       
        
         t
         n
        
        
         t
         total
        
       
       ×
       0.1334
      
      }
     
     ×
     k
    
    ]
   
   ÷
   t
  
 

where Tn denotes a heating furnace atmospheric temperature in an n-th section in a conveying direction of a blank and a unit thereof is degrees Celsius (° C.), ta denotes a heating furnace maintaining time in the n-th section in the conveying direction of the blank and a unit thereof is minute, ttotal denotes total maintaining time in the heating furnace and a unit thereof is minute, x denotes the number of sections maintained at a specific atmospheric temperature in the heating furnace, k is an integer of 3 in the case of a final section in section B, an integer of −1 in the case in which a section subsequent to section B, and an integer of 1 in the other cases, and t denotes a thickness of the blank and a unit thereof is millimeters (mm).