The importance of tapered roller bearings in mechanical products

2021-06-26 16:42

Tapered roller bearings are separable bearings. Both the inner and outer rings of the bearing have tapered raceways. This type of bearing is divided into single-row, double-row and four-row tapered roller bearings according to the number of rows installed. Single row tapered roller bearings can bear radial load and single direction axial load. When the bearing bears radial load, it will produce an axial component force, so another bearing that can bear the axial force in the opposite direction is needed to balance it.

Tapered roller bearings are mainly subjected to combined radial and axial loads based on the radial direction. The bearing capacity depends on the raceway angle of the outer ring, the larger the angle, the greater the bearing capacity. This type of bearing is a separable bearing, which is divided into single-row, double-row and four-row tapered roller bearings according to the number of rows of rolling elements in the bearing. The clearance of single-row tapered roller bearings needs to be adjusted by the user during installation; the clearances of double-row and four-row tapered roller bearings have been set at the factory according to user requirements and do not require user adjustment.

The tapered roller bearing has a tapered inner ring and an outer ring raceway, and the tapered rollers are arranged between the two. All the projection lines of the cone surface converge at the same point on the bearing axis. This design makes tapered roller bearings particularly suitable for bearing compound (radial and axial) loads. The axial load capacity of the bearing is mostly determined by the contact angle α; the larger the angle α, the higher the axial load capacity. The size of the angle is expressed by the calculation coefficient e; the greater the value of e, the greater the contact angle, and the greater the applicability of the bearing to bear the axial load.

Tapered roller bearings are usually separated, that is, the tapered inner ring assembly composed of the inner ring with roller and cage assembly can be installed separately from the tapered outer ring (outer ring).

The single row tapered roller bearing has an outer ring, its inner ring and a set of tapered rollers are enclosed by a basket-shaped cage to form an inner ring assembly. The outer ring can be separated from the inner ring assembly. According to the ISO tapered roller bearing outline dimension standard, the outer ring or inner ring assembly of any standard type of tapered roller bearing should be able to achieve internationality with the outer ring or inner ring assembly of the same model. exchange. That is to say, in addition to the external dimensions and tolerances of the outer ring of the same model, which must meet the requirements of ISO492 (GB307), the cone angle of the inner ring component and the diameter of the component cone must also comply with the relevant regulations for interchange.

Generally, the tapered angle of the outer ring raceway of a single-row tapered roller bearing is before 10°~19°, which can bear the combined action of axial load and radial load at the same time. The larger the cone angle, the greater the ability to withstand axial load. Bearings with large taper angles are coded with B in the rear, and the taper angle is between 25° and 29°, which can bear larger axial loads. In addition, single-row tapered roller bearings can adjust the size of the clearance during the installation process.

The outer ring (or inner ring) of a double-row tapered roller bearing is a whole. The small end faces of the two inner rings (or outer rings) are similar, and there is a spacer in the middle. The clearance is adjusted by the thickness of the spacer. The thickness of the spacer can also be used to adjust the pre-interference of the double-row tapered roller bearing.

Four-row tapered roller bearings. The performance of this type of bearing is basically the same as that of double-row tapered roller bearings, but it bears greater radial load than double-row tapered roller bearings and has a slightly lower limit speed. It is mainly used for heavy machinery, such as Rolling mills, etc.