Double-row tapered Roller Bearings can replace two single-row tapered roller bearings mounted back-to-back or face-to-face when the required capacity exceeds that of single-row tapered roller bearings. If the tapered roller bearing contact lines converge away from the bearing axis, the bearing is more tolerant to misalignment.
If they converge toward the axis, the tapered roller bearing has higher resistance to moment loading, but lower tolerance for misalignment.