What are the factors causing the temperature rise of deep groove ball bearings?

What factors cause the internal temperature rise of deep groove ball bearings? When the temperature of deep groove ball bearings is not significantly higher than the temperature of deep groove ball base, the overall heat of deep groove ball bearings is not the main component of deep groove ball heat, and the temperature distribution at this time conforms to the normal temperature distribution. Therefore, from the perspective of temperature distribution, the possibility of judging that the bearing is faulty can be roughly reduced. When the temperature of deep groove ball bearings is significantly higher than the temperature of the surrounding deep groove ball end cover and base, the bearing, as a major heating element of the whole, significantly affects the overall temperature distribution of the deep groove ball.
The main factors causing deep groove ball bearings to heat up include the following points
1. Load of deep groove ball bearings
2. Speed of deep groove ball bearings
3. Lubrication of deep groove ball bearings
4. Sealing of deep groove ball bearings
5. Related pollution in the bearing
6. Damage inside the bearing