Edge flatness monitoring

Abstract

A metallic strip edge flatness monitoring system for a rolling mill has one or more thermal imaging devices ( 105 ) arranged to monitor temperature or temperature variances across at least one region of interest ( 108, 115 ) in the rolling mill. The monitored temperature or temperature variances are input to a flatness control system ( 107 ) and a control signal is generated in the flatness control system to modify actuation of actuators ( 106 ) in the rolling mill. The region of interest ( 108, 115 ) has a width of less than half the width of the metallic strip ( 101 ) and has a region on each side of the strip. The total width monitored is less than half the total width of the metallic strip.

1 . A metallic strip edge flatness monitoring system for a rolling mill, the system comprising one or more thermal imaging devices arranged to monitor temperature or temperature variances across at least one region of interest in the rolling mill; wherein the monitored temperature or temperature variances are input to a flatness control system; wherein a control signal is generated in the flatness control system to modify actuation of actuators in the rolling mill; wherein the region of interest has a width of less than half the width of the metallic strip; and wherein the region of interest comprises a region on each side of the strip and the total width monitored is less than half the total width of the metallic strip. 
     
     
         2 . A system according to  claim 1 , wherein the region of interest is on a periphery of one or more work rolls. 
     
     
         3 . A system according to  claim 1 , wherein the region of interest is on an input or exit side of the rolling mill. 
     
     
         4 . A system according to  claim 1 , wherein the region of interest extends between a nip of the work rolls and a nip of a work roll and an adjacent support roll. 
     
     
         5 . A system according to  claim 1 , wherein the region of interest is at an edge of the metallic strip exiting the work rolls. 
     
     
         6 . A system according to  claim 5 , wherein the region of interest has a length less than the length of the metallic strip between a nip of the work rolls and a strip re-coiler. 
     
     
         7 . A system according to  claim 1 , wherein the system further comprises a fixed mount thermal imaging device with a field of view capable of measuring the temperature or temperature variances for all product width combinations in a particular application. 
     
     
         8 . A system according to  claim 1 , wherein the system further comprises a mount for each thermal imaging device, each mount being adapted to allow transverse movement of the device across the width of the region of interest on the metallic strip. 
     
     
         9 . A system according to  claim 8 , wherein the device adjusts its transverse position in response from up to date information in the control system on the product being rolled. 
     
     
         10 . A system according to  claim 8 , wherein the device adjusts its transverse position in response to edge position detected by the thermal imaging device. 
     
     
         11 . A system according to  claim 1 , wherein the system further comprises a flatness measurement device on the exit side of the rolling mill. 
     
     
         12 . A system according to  claim 1 , wherein the actuators comprise at least one of hot edge spray controllers and inductor controllers. 
     
     
         13 . A system according to  claim 1 , wherein both temperature and temperature variance are monitored. 
     
     
         14 . A method of monitoring strip edge flatness of a metallic strip in a rolling mill; the method comprising the steps of:
 measuring a temperature or temperature variance across a region of interest using a thermal imaging device, wherein the region of interest has a width of less than half of the width of the strip; and wherein the region of interest comprises a region on each side of the strip and the total width monitored is less than half the total width of the metallic strip,   deriving a control signal based on the measured temperature or temperature variance; and   controlling operation of actuators in the rolling mill using the derived control signal to provide enhanced edge shape control.   
     
     
         15 . A method according to  claim 14 , wherein the temperature, or temperature variance, is measured on a periphery of one or more work rolls. 
     
     
         16 . A method according to  claim 15 , wherein the region of interest is on an exit side of the rolling mill. 
     
     
         17 . A method according to  claim 14 , wherein the region of interest extends between a nip of the work rolls and a nip of a work roll and an adjacent support roll. 
     
     
         18 . A method according to  claim 14 , wherein the region of interest is at an edge of the metallic strip on an exit side the rolling mill. 
     
     
         19 . A method according to  claim 18 , wherein the temperature, or temperature variance, is measured over a section of length less than or equal to the length of the metallic strip between a nip of the work rolls and a strip re-toiler. 
     
     
         20 . A method according to  claim 14 , wherein the method further comprises a fixed mount thermal imaging device with a field of view capable of measuring the temperature or temperature variances for all product width combinations in a particular application. 
     
     
         21 . A method according to  claim 14 , wherein the method further comprises a mount for each thermal imaging device, each mount being adapted to allow transverse movement of the device across the width of the region of interest on the metallic strip. 
     
     
         22 . A method according to  claim 21 , wherein the device adjusts its transverse position in response from up to date information in the control system on the product being rolled. 
     
     
         23 . A method according to  claim 21 , wherein the device adjusts its transverse position in response to edge position detected by the thermal imaging device. 
     
     
         24 . A method according to  claim 14 , wherein the method further comprises measuring flatness of the strip using a flatness measurement device on the exit side of the rolling mill. 
     
     
         25 . A method according to  claim 24 , further comprising inputting signals from the flatness measurement device to the flatness control system to further modify the control signal to the actuators. 
     
     
         26 . A method according to any of  claims 14 , wherein both temperature and temperature variance are monitored.