Maintenance-free bearings are used in the process without adding lubricants, as long as used properly, generally used to the end of life when the maintenance-free bearings are mainly characterized by: light weight high strength self-lubrication maintenance-free corrosion resistance dust resistance wear low friction coefficient lower than copper 8.3 times to replace stainless steel aluminum alloy copper products Maintenance-free bearings can also dry run, sealed forced lubrication bearings, into dry lubrication, it can greatly avoid the failure of the lubrication system, resulting in bearing damage, will not oil rise, can be used in oil-water mixing environment; Maintenance-free bearings significantly reduce the consumption of grease by optimizing the geometry and surface finish of the bearing channel, redesigning the reholder, combining the use of high-performance bearing steel with a unique heat treatment process, and improving the accuracy of the ball.