Oil-free bearings with high carrying capacity, impact resistance, high temperature, self-lubricating ability and other characteristics, especially for heavy, low speed, reciprocating or swing difficult to lubricate and the formation of oil film occasions, not afraid of water and other acid Erosion and erosion. Due to the special requirements of the production process, some of the key equipment of industrial and mining enterprises in extremely harsh conditions to run. As the equipment heavy, high ambient temperature, dust or air containing acidic corrosive gases CO, SO2, etc., the equipment lubrication to bring a lot of problems, serious friction and wear.