| 摘要 |
PURPOSE: To provide a hearth roll which substanitally prevents the occurrence of a temp. distribution in this roll and substantially prevents the occurrence of a thermal crown as well even if coming into contact with metallic strips of various temps. CONSTITUTION: This hearth roll consists of a carbon material having a coefft. of linear expansion of <=6×10<-6> [1/ deg.C] and thermal conductivity of >=100[W/mk] in the cylindrical part of the roll in contact with the metallic strip. The outer side of the carbon material has a coating layer of a metal, ceramic or cermet having a thickness of <=5mm. As the result, the temp. distribution hardly occurs in the roll and the thermal crown hardly occurs in the roll and, therefore, the occurrence of the heat buckle in the metallic strip is prevented. As the result, not only the product quality is improved but the damage of the roll occurring in the heat buckle is prevented as well. |
