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Why choose tapered roller bearings?
1. High speed and high precision;
2. High rigidity, impact resistance and vibration resistance;
3. Can bear large axial load;
4. High rolling contact fatigue strength;
5. With high hardness and high mechanical strength, the product has high wear resistance;
6. The product has high dimensional stability;
Classification of tapered roller bearings:
Single row tapered roller bearings have an outer ring, an inner ring assembly of which the inner ring and a set of tapered rollers are enclosed by a basket cage. The outer ring can be separated from the inner ring assembly. According to the ISO tapered roller bearing dimension standard, the outer ring or inner ring assembly of any standard type of tapered roller bearing should be able to achieve international performance with the same type of outer ring or inner ring assembly. exchange. That is to say, the outer ring of the same type must comply with the ISO492 (GB307) regulations in addition to the external dimensions and tolerances, and the cone angle of the inner ring component and the diameter of the component cone must also comply with the relevant regulations for interchangeability.
Generally, the taper angle of the outer ring raceway of a single-row tapered roller bearing is between 10° and 19°, which can bear the combined effect of axial load and radial load at the same time. The larger the cone angle, the greater the ability to bear the axial load. Bearings with large taper angle, post code plus B, taper angle between 25°~29°, it can bear large axial load. In addition, single row tapered roller bearings can adjust the size of the clearance during installation.
The outer ring (or inner ring) of a double row tapered roller bearing is a single piece. 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 bearing, the performance of this type of bearing is basically the same as that of double-row tapered roller bearing, but the radial load is larger than that of double-row tapered roller bearing, and the limit speed is slightly lower. It is mainly used for heavy machinery.
Multi-sealed double and four-row tapered roller bearings, Tradebearings provides long-life, multi-sealed double and four-row tapered roller bearings. Carry out a new personalized design for the bearing, change the traditional design method of the fully sealed bearing, and adopt a new type of sealing structure combining sealing and dustproof to improve the sealing effect and improve the sealing performance. Compared with the open structure bearing, the multi-sealed double-row and four-row tapered roller bearings have a 20% to 40% increase in service life and an 80% reduction in lubricant consumption.
Features and uses of tapered roller bearings:
Tapered roller bearings mainly bear the combined radial and axial loads mainly in the radial direction. The bearing capacity depends on the raceway angle of the outer ring, and 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 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 tapered inner and outer raceways with tapered rollers arranged in between. The projected 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 α; the larger the α angle, the higher the axial load capacity. The size of the angle is represented 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 assembly consisting of the inner ring with the roller and cage assembly can be installed separately from the tapered outer ring (outer ring).
Tapered roller bearings are widely used in automobiles, rolling mills, mining, metallurgy, plastic machinery and other industries.
Notes on the use of tapered roller bearings:
The main reasons for the occurrence of scars in the installation process of tapered roller bearings are: the inner ring and outer ring are skewed during the installation and assembly of the bearing; or it may be the occurrence of the charging load in the process of installation and assembly, which eventually causes the bearing to appear scars .
When installing the tapered roller bearing, it must be carried out according to the working specifications. Otherwise, there will be many problems, such as improper installation form or method, which will cause linear scars on the raceway surface and bone surface of the bearing. The device of the deep groove ball bearing indirectly reflects the precision, life and function of the bearing in use.
Although the quality of tapered roller bearings is relatively good, rolling bearings are precision parts, and their use must also be carried out with caution. No matter how high-performance bearings are used, if used incorrectly, the expected performance will not be obtained. The precautions for the use of bearings are as follows:
(1) Keep the tapered roller bearing and its surroundings clean.
Even small dust that is invisible to the eye can have a bad effect on the bearing. Therefore, keep the surrounding clean so that dust does not penetrate the bearing.
(2), use with caution.
When a tapered roller bearing is given a strong impact during use, scars and indentations will occur, which may cause accidents. In severe cases, cracks and fractures may occur, so care must be taken.
(3), use appropriate operating tools.
Avoid replacing existing tools, you must use the right tools.
(4) Pay attention to the corrosion of tapered roller bearings.
Sweat on your hands can be the cause of rust when handling bearings. Be careful to operate with clean hands, and it is best to wear gloves as much as possible.
It is a common method for tapered roller bearings to use hearing to identify irregular operation. For example, using an electronic stethoscope to detect abnormal noise of a part is used by experienced operators. If the bearing is in good operating condition, it will emit a low whine sound, and if it emits a sharp hissing sound, tapered roller bearing, squeaking sound and other irregular sounds, it usually indicates that the bearing is in poor operating condition.
1. Corrosion of tile surface: Spectral analysis found that the concentration of non-ferrous metal elements was abnormal; many sub-micron wear particles of non-ferrous metal components appeared in the ferrography; the moisture content of the lubricating oil exceeded the standard and the acid value exceeded the standard.
2. Strain on the journal surface: There are iron-based cutting abrasive particles or black oxide particles in the ferrography, and there is a tempered color on the metal surface.
3. Surface corrosion of the journal: Spectral analysis found that the iron element concentration was abnormal, there were many sub-micron particles of iron composition in the ferrography, and the moisture content of the lubricating oil exceeded the standard or the acid value exceeded the standard.
4. Surface strain: There are cutting abrasive particles found in the ferrography, and the abrasive particles are non-ferrous metals.
5. Fretting wear of tile back: Spectral analysis found that the iron concentration was abnormal, there were many sub-micron wear particles of iron composition in the ferrography, and the moisture and acid value of the lubricating oil were abnormal.
Under the condition of liquid lubrication, the sliding surfaces are separated by the lubricating oil without direct contact, which can greatly reduce friction loss and surface wear, and the oil film also has a certain ability to absorb vibration
High-pitched creaking noises can be caused by improper lubrication. Improper bearing clearance can also cause metallic noise. The dent on the outer ring track of the tapered roller bearing will cause vibration and cause a smooth and crisp sound. If it is due to the knocking scar caused by the installation, it will also generate noise.
The noise will vary with the speed of the bearing. If there is intermittent noise, it means that the rolling parts may be damaged. The sound of tapered roller bearings occurs when the damaged surface is rolled over. If there is contamination in the bearing, it will often cause hissing sound. Serious bearing damage will cause Irregular and loud noises are produced.
Bearing damage can be detected by hearing, but usually the bearing has to be replaced immediately. Therefore, the better method is to use, for example, electronic condition monitoring equipment, to pre-break the running condition of the tapered roller bearing.
