| 摘要 |
PURPOSE:To heat the edge part of a steel material in excellent thermal efficiency with a simple installation by providing a heat-transmission accelerating body capable of freely advancing and retreating to the furnace inside of a burner provided to the side wall of a heating furnace used for heating the steel material to be heated and moving the body in accordance with the width of material to maintain the constant distance between it and the end part of material. CONSTITUTION:In hot rolling a steel sheet 2, as the edge part is cooled more than the central part to a lower temp., the sheet 2 is not rolled after heating its edge part in a heating furnace 1 to prevent the edge part from generating defects such as an edge crack or a waviness. In this case, through-holes 4 are provided to both side walls of the furnace 1 to be used, and burners 6 are attached to their insides, and ceramic cylinders 8 equipped with heat-transmission accelerating bodies 10 which are enabled to advance or retreat by motor-driven cylinders 11 are also attached to the insides. The body 10 is formed by using a porous body of heat-resisting material such as a metal or ceramics, which radiates radiation heat when heated to high temp. by the bunrner 6 to heat the edge part of sheet 2. When the width of sheet 2 is change, the body 8 is advanced or retreated to make the distace from the edge part of sheet 2 constant, thereby heating the edge part in excellent thermal efficiency. |
