Spherical roller bearings are double row ball, is characterized by an outer ring raceway spherical shape, rotation, tilt freely ball, cage, inner to the outer ring mandrel can do that with a certain degree of self-aligning performance can automatically adjust the shaft and housing due to processing, installation axis offset and shaft deflection occurs due to improper error, but the inner and outer rings relative inclination of not more than 3 degrees. Such bearings are mainly used to bear radial load, but also can bear radial load mainly withstand small axial load, but can not afford pure axial load. The basic design type has a cylindrical and tapered bore has two structures, conical taper bore 1:12. Its sealed bearings are 2RS contact with seals, bearing infill lithium grease for operating temperatures from -30 to 110 degrees, the use of permanently lubricated, non-heated before installation should not be cleaned. Cage made of steel sheet, synthetic resin, glass fiber reinforced nylon 66 cage as the standard cage, this material is a good process, light weight, self-lubricating properties, can adapt to the high speed of operation, the operating temperature of most Master of up to 120 degrees. Angular contact ball bearings can support radial and axial load, single row angular contact ball bearings can withstand axial load in one direction, so often adopted installed in pairs. When used in pairs to Cuba to adjust the pairing gap is most convenient angular contact ball bearings, cage made of brass, synthetic resins, etc., depending on the bearing form, and application conditions.