These bearings have barrel-shaped rollers between the inner ring, which has two raceways and the outer ring which has one spherical raceway Since the center of curvature of the outer ring raceway surface coincides with the bearing axis hey are self-aligning in a manner similar to that of self-aligning ball bearings Therefore, if three is deflection of the shaft or housing or misalignment of their axes it is automatically corrected so excessive force is not applied to the bearings. Spherical roller bearings can take, not only heavy radial loads, but also some axial loads in either direction. They have excellent radial load carrying capacity and are suitable for use where there are heavy or impact loads Some bearings have tapered bores and may be mounted directly an tapered shafts or cylindrical shafts using adapters or withdrawal sleeves. Pressed-steel, molded polymide and machined brass cages are used