Taper roller bearings have tapered cone and cup between which taper rollers are arranged. The extension lines of them intersect at one point of shaft axis; therefore, pure rolling on the raceway can be achieved. Taper roller bearings are separable. Bearing cone (including roller, cage and inner ring) and cup (outer ring) can be separated, therefore, it can be easily assembled on the bearing journal and bearing block. Taper roller bearings are able to accommodate radial loads, unidirectional axial loads and combined loads of radial and axial.