When the bearing model is used at high temperature, the material structure will change, the hardness will be reduced, and the basic dynamic load rating will be lower than when used at room temperature. Once the material structure changes, it will not recover even if the temperature returns to normal temperature. Therefore, when used at high temperatures, the basic dynamic load rating of the bearing use table must be multiplied by the temperature coefficient in Table 4 for trimming. Table 4: Temperature Coefficient of Bearing Working Temperature Temperature Coefficient (fT) 125 150 175 200 250 1 1 0.95 0.90 0.75 When the bearing is used for a long time at a working temperature above 120℃, the bearing size after general heat treatment changes greatly, so it must be dimensioned Stable processing. The dimensional stability treatment code and operating temperature range are shown in Table 5. However, the hardness of the dimensionally stabilized bearing is reduced, and sometimes the basic dynamic load rating will be reduced. Dimensional stability treatment code. Operating temperature range S0 exceeds 100°C to 150°C, S1 exceeds 150°C to 200°C, and S2 exceeds 200°C to 250°C