Endless rolling apparatus and method

Abstract

Provided is an endless rolling apparatus and method, which have improved cooling conditions for producing advanced high strength steel. The endless rolling apparatus includes: a continuous casting machine for casting a slab; and a cooling bed having at least one piece of water-cooling equipment and at least one rolling mill continuously connected to the continuous casting machine, wherein, in the cooling bed, an initial position (S) at which the water-cooling equipment is provided so as to manufacture advanced high strength steel through at least one water-cooling is defined by mathematical formula 1. Here, H is the thickness (mm) of a slab, V is the casting speed (m/sec) of the slab, h is the product thickness (mm), and t is the target arrival time (sec) until entry into the cooling bed.

1 . An endless rolling apparatus comprising a continuous casting device casting a slab and a cooling bed having at least one rolling mill and at least one water-cooling device, continuously provided with the continuous casting device,
 wherein, in the cooling bed, an initial position (S), at which the water-cooling device is provided to manufacture advanced high strength steel through at least one water-cooling, is defined by Formula 1,   
       
         
           
             
               
                 
                   
                     S 
                     = 
                     
                       
                         
                           ( 
                           
                             H 
                             · 
                             V 
                           
                           ) 
                         
                         h 
                       
                       · 
                       
                         t 
                          
                         
                           ( 
                           
                             HERE 
                             , 
                             
                               0 
                               < 
                               t 
                               < 
                               
                                 10 
                                  
                                 
                                     
                                 
                                  
                                 sec 
                               
                             
                           
                           ) 
                         
                       
                     
                   
                 
                 
                   
                     Formula 
                      
                     
                         
                     
                      
                     1 
                   
                 
               
             
           
         
         where H is the thickness (mm) of the slab, V is the casting speed (m/sec) of the slab, h is product thickness (mm), and t is target arrival time (sec) until entry into the cooling bed. 
       
     
     
         2 . An endless rolling method comprising:
 a casting operation of casting a slab using a continuous casting device;   a casting speed and thickness measuring operation of measuring a casting speed of the slab produced in the casting operation and a thickness (H) of the slab;   a rolling operation of rolling the slab, continuously connected to the continuous casting device, to a target thickness;   a product thickness measuring operation of measuring a thickness of a product rolled in the rolling operation;   a target arrival time setting operation of setting the target arrival time required for the product to enter a water cooling section of a cooling bed after completion of the rolling operation; and   a water cooling start position calculating operation of setting an initial cooling start position (S) to manufacture advanced high strength steel through at least one water-cooling in the cooling bed using a value obtained in each operation.   
     
     
         3 . The endless rolling method of  claim 2 , wherein the water cooling start position calculating operation is defined by Formula 1, 
       
         
           
             
               
                 
                   
                     S 
                     = 
                     
                       
                         
                           ( 
                           
                             H 
                             · 
                             V 
                           
                           ) 
                         
                         h 
                       
                       · 
                       
                         t 
                          
                         
                           ( 
                           
                             HERE 
                             , 
                             
                               0 
                               < 
                               t 
                               < 
                               
                                 10 
                                  
                                 
                                     
                                 
                                  
                                 sec 
                               
                             
                           
                           ) 
                         
                       
                     
                   
                 
                 
                   
                     Formula 
                      
                     
                         
                     
                      
                     1 
                   
                 
               
             
           
         
         where H is the thickness (mm) of the slab, V is the casting speed (m/sec) of the slab, h is product thickness (mm), and t is target arrival time (sec) until entry into the cooling bed. 
       
     
     
         4 . The endless rolling method of  claim 2 , wherein, when the rolling operation is completed, a temperature of the product is controlled to 750° C. to 880° C. 
     
     
         5 . The endless rolling method of  claim 3 , wherein, when the rolling operation is completed, a temperature of the product is controlled to 750° C. to 880° C.