Self-aligning roller bearing has two rows of spherical rollers, the outer race is provided with a common concave spherical raceway, while the inner race is provided with two concave spherical raceways that form an angle with the bearing axis. The curvature center of the outer raceway is consistent with the bearing center.

The self-aligning roller bearing is self-adjusted, and it is not affected by non-centering or shaft deformation flexure of shaft and bearing block, so it can compensate the concentricity error caused by these reasons. Except being subject to radial load, this type of bearing can also be subject to bidirectional axial load and their combination load. The load capacity is large, and the bearing is provided with preferable shock resistant capacity. Self-aligning roller bearings are mainly applied on mechanical equipments of steel, mine, paper making, shipping, textile machinery, coal mill and electric power industries. It is one of the bearings most widely used in mechanical industry.