The roll used in a heat treating furnace is called hearth roll, which has been changed very frequently. This is because high temperate of a furnace induces wear on the roll surface in short period. This paper deals with a new roller structure consisting of ceramics sleeve connected to two steel shafts by shrink fitting because the ceramics has high temperature resistance and high corrosion resistance. However, attention should be paid for the risk of fracture due to the thermal expansion difference between ceramics and steel. In this study the finite element method is applied to calculate the stress appearing at connecting parts with varying the geometries of the shaft. To design the structure safety, it is found that tapered shaft with smaller thickness is most designable for the ceramic hearth roll.
