The primary reasons for bearing temperature rise in forward-curved double-inlet centrifugal fan units are as follows:

The primary reasons for bearing temperature rise in forward-curved double-inlet centrifugal fan units are as follows: 1. Severe vibration of the bearing housing. 2. Poor lubricant quality, aging, excessive impurities, or improper filling quantity. 3. Misalignment of the shaft and rolling bearings, resulting in non-coaxial front and rear bearings. 4. Rotation of the outer ring of the rolling bearing (friction against the bearing housing). 5. Rotation of the inner ring of the roller bearing relative to the main shaft (i.e., friction between inner ring and main shaft). 6. Damage to the rolling bearing or shaft deflection. 7. Insufficient or interrupted cooling water supply (for fans requiring water-cooled bearings).