1) Oil-retaining bearing low precision
;
the service life of 20000 hours, total: 834 days, 2. 3 years;
line contact bearings and shaft relative motion;
running friction;
mining vacuum storage in the immersion in the bearing inner surface oil hole, the running friction hot forming oil film lubrication;
the fan to use fixed better adopt vertical way.
2) A single ball bearing
accuracy is poorer;
the service life of 30000 hours, total: 1250 days, 3. 4 years;
line, point contact are;
running friction times;
use method has both the characteristics of oil bearing/double ball bearing operating load mainly fall in front of ball, and then the copper is to provide protection effect, and heart degrees of adjustment according to the ball's position effect;
fan fixed vertical direction using the better.
3) Double ball bearing
the highest accuracy;
the service life of 50000 hours, total: 2084 days, 5. Seven years;
bearing and shaft relative motion of point contact;
movement friction is smaller;
mining internal ball bearings with grease under retainer positioning rotary motion;
fixed fan in any direction.