Function and application of tapered roller bearing

Tapered roller bearings mainly bear radial and axial combined loads. The bearing capacity depends on the raceway angle of the outer ring. The greater the angle, the greater the bearing capacity. This kind of bearing is a separate 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 bearing needs to be adjusted by the user during installation; The clearance of double row and four row tapered roller bearings has been given according to the user's requirements when the product leaves the factory and does not need to be adjusted by the user.

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

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

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

The main reasons for the scratches of tapered roller bearing in the process of installation are: the inner ring and outer ring of the bearing are skewed during installation and assembly; or it may be the emerging charge load in the process of installation and assembly, and finally form the scar of bearing.

When installing tapered roller bearing, it shall be stopped according to the working specifications, and many achievements will not be formed. If the form or method of the device is not appropriate, linear scars will be formed on the raceway surface and bone surface of the bearing. The device of deep groove ball bearing indirectly reflects the precision, service life and function of the bearing.

Although the quality of tapered roller bearings is relatively good, rolling bearings are precision parts, and their use must be carried out with corresponding caution. No matter how high-performance bearings are used, if they are not used properly, the expected high performance will not be obtained. There are the following precautions for the use of bearings:

(1) Keep tapered roller bearings and their surroundings clean.

Even small dust that cannot be seen by the eyes will have a bad impact on the bearing. Therefore, keep the surrounding clean so that dust will not invade the bearing.

(2) Use with care.

When the tapered roller bearing is strongly impacted in use, it will produce scars and indentation, which will become the cause of the accident. In serious cases, it will crack and fracture, so we must pay attention to it.

(3) Use proper operation tools.

Avoid replacing with existing tools, and appropriate tools must be used.

(4) Pay attention to the corrosion of tapered roller bearings.

When operating the bearing, the sweat on the hand will become the cause of rust. Pay attention to operate with clean hands, and it is best to wear gloves as much as possible.

It is a very common method for tapered roller bearings to use hearing to identify irregular operation. For example, it is used by experienced operators to detect the abnormal noise of a part with the help of electronic stethoscope. If the bearing is in good operation condition, it will make a low whine. If it makes a sharp hiss, tapered roller bearing, squeak and other irregular sounds, it usually indicates that the bearing is in poor operation condition.

1. Tile surface corrosion: abnormal concentration of non-ferrous metal elements is found by spectral analysis; Submicron wear particles with many nonferrous metal components appear in ferrography; The water content and acid value of lubricating oil exceed the standard.

2. Journal surface strain: there are ferrous cutting abrasive particles or black oxide particles in the ferrogram, and there is tempering color on the metal surface.

3. Journal surface corrosion: abnormal iron concentration is found by spectral analysis. There are many submicron particles of iron in the ferrogram, and the moisture or acid value of lubricating oil exceeds the standard.

4. Surface strain: cutting abrasive particles are found in ferrography, and the abrasive particles are composed of non-ferrous metals.

5. Fretting wear of pad back: abnormal iron concentration is found by spectral analysis. There are many iron components, submicron wear particles, abnormal moisture and acid value of lubricating oil in the ferrogram.

Under the condition of liquid lubrication, the sliding surface is separated by the lubricating oil without direct contact, which can also greatly reduce the friction loss and surface wear, and the oil film also has a certain vibration absorption ability

Sharp squeaking noises may be caused by improper lubrication. Improper bearing clearance can also cause metal sound. The dent on the outer race track of tapered roller bearing will cause vibration and cause smooth and crisp sound. If it is due to the knocking scar caused during installation, it will also produce noise, which will vary with the bearing speed. If there is intermittent noise, it means that the rolling parts may be damaged. The sound of tapered roller bearing occurs when the damaged surface is rolled out. If there are pollutants in the bearing, it will often cause hiss, and serious bearing damage will produce irregular and huge noise.

Bearing damage can be detected by hearing, but usually it has arrived at this time and the bearing must be replaced immediately. Therefore, a better method, such as using electronic condition monitoring instruments, is to pre break the operation of tapered roller bearings.