"Cooling Fan Manufacturer" bearing system generally recommend the best selection of ball bearings, fan heat fan because life often depends on the reliability of its bearings, ball bearing system has been shown to have the characteristics of high efficiency and low heat generation. "Cooling Fan Manufacturer" rolling friction ball bearing genera, rolling of metal beads, small contact surface, the friction coefficient is small; and oil-bearing for sliding friction, a large contact surface, after long-term use, the oil will be volatile, bearing easy to wear, friction coefficient late noisy, short life. "Cooling Fan Manufacturer" the use of oil-bearing copper-based sintered powder is made by using a lubricating oil bearings need to reduce the number of sliding friction, by lithium grease lubricating oil system Stuttgart modulation.