Four-row tapered roller bearings are used successfully worldwide for rolling mill bearing arrangements where rolling speeds are slow to moderate. Because of their design they are able to take up those axial loads which occur in such applications in addition to radial loads and generally no separate thrust bearings are required in such arrangements. This means that the roll necks can be relatively short and the chocks at both sides of the roll can have the same design.

Spherical roller bearing can bear heavy load, it has two row rollers, one common spherical raceway in outer ring, two raceway in the inner ring which inclined to a certain angle relative to the center line of axis, the bearing can be automatically self-aligning. when the bearing bent by the force or its installation of different mind,the bearing can still be normal use. Such bearing can withstand both radial load and bi-directional axial load, the fight ability is better.

Generally, spherical roller bearing permit the work of low speed.