Self-aligning roller bearings generally have two rows of rollers, and the performance characteristics are : low speed, impact resistance, vibration resistance; with automatics aligning function, namely it normally operates with larger inclination for the inner axis relative to outer axis(generally within 3 degree); mainly bear greater radial load as well as smaller axial load. Mainly being applied in metallurgical and mining machinery, engineering machinery, hoist-transport machinery, paper manufacturing machinery and textile machinery ,etc.