PURPOSE: To constitute the title method so that it is easy and a sheet thickness distribution of a widthwise direction of a sheet becomes uniform, by a method wherein a temperature of the central sheet of the widthwise direction of a rolling material is made lower than that of an end part of the sheet.
CONSTITUTION: An end part of a sheet, which is apt to cool, is heated at a temperature higher than that of the central part of the sheet and rolled, in heating of a material before rolling. It is good that a setting temperature of an end of the sheet and that of the center of the sheet are set up by making use of a temperature obtained by performing a preliminary test with the sheet preheated at a uniform temperature. A material 7 may be heated by covering 8 heat transfer of a part which is to make into a low temperature by making use, for example, of an infrared heater 6 or cooled in some cases as a method providing a temperature difference. On the contrary, the part which is to heat may be heated with infrared rays/hot air 6. It is good that a far-infrared heater/ hot air furnace/plate heater placing an article between a top and bottom heating sheets are used as a heating device.
WATANABE KAZUO
TSUKASAKI HIDEYUKI
