what's the Oil-free bearings?

Oil-free lubrication bearings are divided into solid inlaid bearings, composite bearings, oil-containing bearings, and new single lubricating materials from the product structure:

Solid inlaid bearings
It is common to embed solid lubricating materials such as graphite (black lead), polytetrafluoroethylene (PTFE), molybdenum disulfide, etc., into alloy materials such as high-strength brass, tin bronze, aluminum bronze, cast iron, or GCr15 using an inlay process. It breaks through the limitations of general sliding bearings that rely on oil film lubrication. In the process of use, the solid lubrication and the shaft are rubbed by frictional heat, forming an excellent condition for the coexistence of oil and powder lubrication, which not only protects the shaft from wear, but also makes the solid lubrication properties eternal. The hardness of high-strength brass is twice as high as that of ordinary copper sleeves, the wear resistance is also twice as high, and the Bearing capacity is high.
Composite bearing
Common composite bearings are composed of two layers of steel plate and copper powder layer (bimetal), or composed of three layers of steel plate, copper powder layer and self-lubricating material (PTFE, PEEK, POM) + filler material. It uses a high-temperature sintering process to bond the self-lubricating material to the steel plate, which not only ensures the friction and wear performance of the working surface of the product, but also ensures the structural stability and load-carrying capacity of the bearing.
Oil bearing
Oil-impregnated bearings are made of metal materials. The bearings are lubricated during production and the lubricating oil is sealed in the bearings. No oil lubrication is required during use to achieve the "self-lubricating" effect. Because the bearing contains oil lubricating oil, it has good lubricity and avoids the work of oiling and maintenance.
New type single lubricating material bearing
New types of single lubricating material bearings commonly include resin, ceramic, tungsten carbide bearings, etc., and new materials are constantly being developed, but this type of bearing may have the characteristics of high cost and narrow application area, so it cannot be widely promoted. Replace rolling bearings.