Matters related to tapered roller bearings

Jun 26, 2023

Tapered roller bearings have tapered inner and outer ring raceways with tapered rollers arranged in between. The projection lines of all conical surfaces meet at the same point on the bearing axis. This design makes tapered roller bearings particularly suitable for combined (radial and axial) loads. The axial load capacity of the bearing is mostly determined by the contact angle a; the larger the angle a, the higher the axial load capacity. The size of the angle is expressed by the calculation coefficient e; the larger the value of e, the larger the contact angle, and the greater the applicability of the bearing to bear the axial load.

Tapered roller bearings are usually separable, that is, the tapered inner ring consisting of a roller and cage assembly, can be installed separately from the tapered outer ring. According to the number of rows of rolling elements in the bearing, they are classified as single-row, double-row, and four-row tapered roller bearings.

Tapered roller bearings are widely used in automobiles, rolling mills, mining, metallurgy, plastic machinery, and other industries.

Installation of tapered roller bearings:

1. The installation of bearings must be carried out under dry and clean environmental conditions. Before installation, carefully check the processing quality of the mating surface of the shaft and the housing, the end face of the shoulder, the groove, and the connection surface. All mating connection surfaces must be carefully cleaned and deburred, and the unprocessed surface of the casting must be cleaned of molding sand.

2. Bearings should be cleaned with gasoline or kerosene before installation and used after drying with good lubrication. Bearings are generally lubricated with grease or oil. When using grease lubrication, grease with excellent properties such as no impurities, anti-oxidation, anti-rust, and extreme pressure properties should be considered. The amount of grease filling is 30%-60% of the volume of the bearing and bearing box, and should not be too much. The double-row tapered roller bearings and four-row tapered roller bearings with sealed structures have been filled with grease, which can be used directly by the user without further cleaning.

3. When the bearing is installed, it is necessary to apply equal pressure on the circumference of the end face of the ring to press the ring. It is not allowed to directly hit the end face of the bearing with a hammer or other tools to avoid damaging the bearing. In the case of small interference, the sleeve can be used to press the end face of the bearing ring at room temperature, and the sleeve can be hit with a hammer to press the ring evenly through the sleeve. If it is installed in large quantities, a hydraulic press can be used. When pressing in, it should be ensured that the end face of the outer ring and the shoulder end face of the shell, and the end face of the inner ring and the shoulder end face of the shaft, are pressed tightly, and no gap is allowed.

4. When the interference is large, the bearing can be installed by oil bath heating or induction heating. The heating temperature range is 80°C-100°C, and the maximum cannot exceed 120°C. At the same time, nuts or other appropriate methods should be used to fasten the bearing to prevent the bearing from shrinking in width after cooling, resulting in a gap between the ring and the shaft shoulder.

5. The clearance should be adjusted at the end of the installation of a single-row tapered roller bearing. The clearance value should be determined specifically according to different operating conditions and the size of the interference fit. When necessary, tests should be carried out to confirm. The clearance of double-row tapered roller bearings and four-row tapered roller bearings have been adjusted before leaving the factory, and no adjustment is required during installation.

6. After installation, a rotation test should be carried out. Above all, it is used for the rotating shaft or bearing box. If there is no abnormality, it will be powered for no-load and low-speed operation and then gradually increase the rotation speed and load according to the operation situation and detect noise, vibration and the temperature rises. If abnormalities are found, the operation should be stopped and checked. It can be delivered for use only after the running test is normal.

FV Metallurgical Bearings provides various types of tapered roller bearings to help customers solve problems.