Cold rolling equipment, steel plate manufacturing equipment, cold rolling method, and steel plate manufacturing method

Abstract

A cold rolling line, a steel sheet production line, a cold rolling method, and a steel sheet production method can suppress work roll deformation and brittle cracking during rolling. The cold rolling line includes one or more cold mills configured to inject coolant towards a work roll and a metal steel strip and to cold roll the metal steel strip, rollers provided upstream from the one or more cold mills in a conveyance direction of the metal steel strip and used to convey the metal steel strip, and a control unit that controls a height difference of the rollers. The control unit controls the rollers so that the metal steel strip is at a lower position towards a downstream side in the conveyance direction at an upstream side of at least a portion of the one or more cold mills including a most upstream mill provided farthest upstream.

1 . A cold rolling line comprising one or more cold mills configured to inject coolant towards a work roll and a metal steel strip and to cold roll the metal steel strip, a plurality of rollers provided upstream from the one or more cold mills in a conveyance direction of the metal steel strip and used to convey the metal steel strip, and a control unit configured to control a height difference of the plurality of rollers, wherein
 the control unit is configured to control the plurality of rollers so that the metal steel strip is at a lower position towards a downstream side in the conveyance direction at an upstream side of at least a portion of the one or more cold mills including a most upstream mill provided farthest upstream.   
     
     
         2 . The cold rolling line according to  claim 1 , wherein the control unit is configured to set an inclination angle of the metal steel strip with respect to a biting area of the one or more cold mills based on at least one of a steel type of the metal steel strip, a line speed, an injection flow rate of the coolant, a temperature of the metal steel strip, and a target temperature of the metal steel strip, at an upstream side of at least a portion of the one or more cold mills including the most upstream mill. 
     
     
         3 . The cold rolling line according to  claim 2 , wherein the control unit is configured to control the plurality of rollers so that the inclination angle is 2° or more and is 10° or less. 
     
     
         4 . The cold rolling line according to  claim 1 , wherein the one or more cold mills comprises a plurality of cold mills, and
 the control unit is configured to control the plurality of rollers so that the metal steel strip is at a higher position towards a downstream side in the conveyance direction at an upstream side of at least a portion of the one or more cold mills including a most downstream mill provided farthest downstream.   
     
     
         5 . A cold rolling line comprising one or more cold mills configured to inject coolant towards a work roll and a metal steel strip and to cold roll the metal steel strip, a plurality of rollers provided upstream from the one or more cold mills in a conveyance direction of the metal steel strip and used to convey the metal steel strip, and a control unit configured to control a height difference of the plurality of rollers, wherein
 the control unit is configured to control the plurality of rollers so that the metal steel strip is at a higher position towards a downstream side in the conveyance direction at an upstream side of at least a portion of the one or more cold mills including a most downstream mill provided farthest downstream.   
     
     
         6 . The cold rolling line according to  claim 5 , wherein the control unit is configured to set an inclination angle of the metal steel strip with respect to a biting area of the one or more cold mills based on at least one of a steel type of the metal steel strip, a line speed, an injection flow rate of the coolant, a temperature of the metal steel strip, and a target temperature of the metal steel strip, at an upstream side of at least a portion of the one or more cold mills including the most downstream mill. 
     
     
         7 . The cold rolling line according to  claim 6 , wherein the control unit is configured to control the plurality of rollers so that the inclination angle is −10° or more and is −2° or less. 
     
     
         8 . A steel sheet production line comprising the cold rolling line according to  claim 1 , and a line for cutting the metal steel strip. 
     
     
         9 . A cold rolling method to be performed on a cold rolling line comprising one or more cold mills configured to inject coolant towards a work roll and a metal steel strip and to cold roll the metal steel strip, a plurality of rollers provided upstream from the one or more cold mills in a conveyance direction of the metal steel strip and used to convey the metal steel strip, and a control unit configured to control a height difference of the plurality of rollers, the cold rolling method comprising:
 controlling, by the control unit, the plurality of rollers so that the metal steel strip is at a lower position towards a downstream side in the conveyance direction at an upstream side of at least a portion of the one or more cold mills including a most upstream mill provided farthest upstream.   
     
     
         10 . A cold rolling method to be performed on a cold rolling line comprising one or more cold mills configured to inject coolant towards a work roll and a metal steel strip and to cold roll the metal steel strip, a plurality of rollers provided upstream from the one or more cold mills in a conveyance direction of the metal steel strip and used to convey the metal steel strip, and a control unit configured to control a height difference of the plurality of rollers, the cold rolling method comprising:
 controlling, by the control unit, the plurality of rollers so that the metal steel strip is at a higher position towards a downstream side in the conveyance direction at an upstream side of at least a portion of the one or more cold mills including a most downstream mill provided farthest downstream.   
     
     
         11 . A steel sheet production method comprising performing the cold rolling method according to  claim 9 , and cutting the metal steel strip. 
     
     
         12 . The cold rolling line according to  claim 2 , wherein the one or more cold mills comprises a plurality of cold mills, and
 the control unit is configured to control the plurality of rollers so that the metal steel strip is at a higher position towards a downstream side in the conveyance direction at an upstream side of at least a portion of the one or more cold mills including a most downstream mill provided farthest downstream.   
     
     
         13 . The cold rolling line according to  claim 3 , wherein the one or more cold mills comprises a plurality of cold mills, and
 the control unit is configured to control the plurality of rollers so that the metal steel strip is at a higher position towards a downstream side in the conveyance direction at an upstream side of at least a portion of the one or more cold mills including a most downstream mill provided farthest downstream.   
     
     
         14 . A steel sheet production line comprising the cold rolling line according to  claim 2 , and a line for cutting the metal steel strip. 
     
     
         15 . A steel sheet production line comprising the cold rolling line according to  claim 3 , and a line for cutting the metal steel strip. 
     
     
         16 . A steel sheet production line comprising the cold rolling line according to  claim 4 , and a line for cutting the metal steel strip. 
     
     
         17 . A steel sheet production line comprising the cold rolling line according to  claim 5 , and a line for cutting the metal steel strip. 
     
     
         18 . A steel sheet production line comprising the cold rolling line according to  claim 6 , and a line for cutting the metal steel strip. 
     
     
         19 . A steel sheet production line comprising the cold rolling line according to  claim 7 , and a line for cutting the metal steel strip. 
     
     
         20 . A steel sheet production method comprising performing the cold rolling method according to  claim 10 , and cutting the metal steel strip.