PURPOSE: To provide the manufacturing technology for a wid-flange shape steel with a thin web by preventing a defective shape after cooling, and by which both of web wave and flange warp do not occur.
CONSTITUTION: In a method for manufacturing a wide-flange shape steel with a thin web by cooling forcedly the outside surface of the flange of the H-shape steel by a cooling means installed on the inlet side of a hot finish rolling mill, it is necessary to respectively find previously the limit value of a difference between the average temperature of a web and that of a flange at the time of a hot finish rolling and the limit value of a difference between the inside surface temperature of the flange and the outside surface temperature of the flange at the time of the hot finish rolling. Next, by finding a difference between the average temperature of the web and that of the flange and a difference between the inside surface temperature of the flange and the outside surface temperature of the flange from the surface temperatures of the web and the flange of the wide-flange shape steel on the inlet side of the cooling means, the water quantity density of a cooling band is adjusted so that these differences in temperature become the limit values of respective differences in temperature or below. Also, the adjustment of the water quantity density of the cooling band is realized by the individual adjustment of the cooling band divided into the line direction.
YOSHIDA HIROSHI
TAKEUCHI TORU
