The inner and outer rings of tapered roller bearings are tapered raceways, and the rolling elements are also tapered, which are separable bearings. The main structural forms are classified according to the number of rolling rows: single-row tapered roller bearings, double-row tapered roller bearings, and four-row tapered roller bearings.

According to the size of the contact angle:

Small cone angle (9°＜a≤25°)
Large cone angle (> 25°) points.

The axial bearing capacity of tapered roller bearings depends on the contact angle a, that is, the raceway angle of the outer ring. The larger the contact angle a, the greater the axial bearing capacity. The size of the angle is expressed by the calculation coefficient e. The greater the value of e, the greater the contact angle.
Generally, it is not allowed to tilt the shaft relative to the shell hole. If there is a tilt, the maximum is not more than 2". If it is required as a roll bearing of a rolling mill due to production process requirements, it will inevitably be subjected to bending force and the axis tilt exceeds 2" , The rollers and raceways of the bearing will generate extra stress, which will increase the load of the bearing and shorten the service life of the bearing. Therefore, the DMD tapered roller bearing has a modified contact shape between the roller and the raceway, especially the four-row tapered roller bearing for rolling mills. In addition to the modified contact shape, the clearance of each row and the inner ring are in contact with the roll neck. The points are all specially designed, which can effectively solve the problem of shortening the life of the bearing caused by the bending force. Double-row tapered roller TDI structure (370000 series) 2 outer rings, integral inner ring, outer ring spacer, the clearance is adjusted by the thickness of the spacer ring, and the thickness of the spacer ring can also be used to adjust the double-row cone Pre-interference of roller bearings. Its performance is similar to the face-to-face installation performance of two single-row tapered roller bearings. Compared with the outward-facing double-row tapered roller bearing TDO structure (350000 series), it has a smaller installation space, but the rigidity is slightly lower. Insensitive to neutrality.