These bearings stay cool while functioning as they consist two rows of balls which lower the friction on the common raceway in the outer ring that helps reduce the heat. These types are ball bearings when the alignment of the shaft and the housing are difficult and the shaft may flex.
Residing in an outer ring the bearing has a spherical raceway and its centre of curvature coincides with that of the bearing, therefore, the axis of the inner ring, balls and cage can deflect to some extent around the bearing center. The smaller contact angle lowers the axial load capacity.
