This kind of bearings’ characteristic is: it has a common concave spherical raceway in the outer ring and double row raceways in the inner ring . this feature gives the bearings their self-aligning property and compensates a certain concentricity error resulting from shaft deflection or improper

Mounting. The linear contact of roller with the raceway can make the bearings, fit for relatively low-speed operation and withstand radial load as well as impulsive load from any direction.