Spherical roller bearings are used to bear radial load, but also can withstand a certain amount of axial load, but generally can not bear the pure axial load. Kind of spherical roller bearing outer ring, thus it has a self-aligning properties, when the axial force to bend or tilt relative to the centerline of leaving the inner slope does not exceed 0.5 ° -2 °, the bearing can still work. Principles and characteristics of its structure and the self-aligning ball bearing the same, the only difference is that the rolling body is a spherical roller, due to the different rolling, so it's a larger carrying capacity, widely used in mining and heavy machinery. Bearing such limit axial displacement of shaft or housing of the axial clearance in the bearing range. Spherical roller bearings and aligning ball equipment, in line with capacity and speed limit permit may be another alternative.