Spherical roller bearings have two rows of spherical rollers, the outer ring has a common concave spherical raceway, the inner ring has two concave raceways that are inclined at an angle to the bearing axis, and the curvature center of the outer ring raceway is the same as the bearing center. Spherical roller bearings are self-aligning, not affected by shaft and bearing box misalignment or shaft deformation deflection, and can compensate for the resulting concentricity error. In addition to bearing radial load, this type of bearing can also withstand two-way axial load and its combined load, with a larger load capacity, while having a better anti-vibration, and anti-impact ability. Spherical roller bearings are mainly used in steel, mining, paper, ships, textile machinery, coal mills, electric power, and other industries in a variety of mechanical equipment, and are the most widely used in the machinery industry in a class of bearings.