Self-aligning ball bearing is a double row ball bearing with spherical outer raceway and two deep groove raceway in inner raceway. It has self-aligning performance. It is mainly used for bearing radial load. While bearing radial load, it can also bear a small amount of axial load, but it generally cannot bear pure axial load, and its limit speed is lower than that of deep groove ball bearings. This kind of bearing is mainly used in the double support shaft which is easy to bend under the load, and in the parts where the double socket hole cannot guarantee strict coaxiality, but the relative inclination of the inner ring center line and the outer ring center line shall not exceed 3 degrees.Self-aligning ball bearings have cylindrical holes and conical holes two kinds of structure, cage material has steel plate, synthetic resin and so on. The raceway of the outer ring is spherical and has automatic centering, which can compensate the errors caused by different concentricity and shaft deflection, but the relative inclination of the inner and outer rings shall not exceed 3 degrees.The deep groove ball bearings with dust cover and sealing ring have been filled with proper amount of grease when they are assembled. They should not be heated or cleaned before installation, and they do not need to be lubricated during use. They can adapt to the operating temperature between -30℃ and +120℃.Suitable for precision instruments, low noise motors, automobiles, motorcycles and general machinery, etc., it is the most widely used kind of bearings in the machinery industry.