Spherical roller bearing has two columns roller, which mainly bear size a load, also can withstand the axial load in any direction. A high radial load capacity, especially suitable for overriden or vibration load work, but unable to bear pure axial load. Such bearing outer ring groove is spherical shape, so its self-aligning performance is good, can compensate the coaxial tolerance of error. Self-aligning roller bearings have two trains symmetric type spherical roller, outside a common spherical groove, inner circle have two and bearing axis tilt Angle of groove, has the good self-aligning performance, when bending or install different axial force heart bearings can still use normally, adjustable tendencies with bearing size series vary, generally allowed by self-aligning Angle for 1 ~ 2.5 degrees, this kinds of bearings ? the capacity of the larger