Ordinary "220V Cooling Fan" is mainly used oil and ball bearings. Dual ball bearing high-end products, high-precision, high-quality, high prices, high product belonging to three. Oil-bearing meet a variety of working conditions, but he is also very long period of use, the price is relatively low, but the quality, relatively speaking, more general. "220V Cooling Fan" is generally dispersed in the radiator used above varieties: use of sliding friction sleeve bearings and ball bearings use rolling friction bearings as well as two forms of combining these three. Over the years many manufacturers introduced many new terms in bearing technology, such as magnetic bearing, water bearing, core bearing, to Fu bearings are also on top of the basic form of the bearing to be improved on, the operating principle remains unchanged. Principle party "220V Cooling Fan" and just work as AC fans.