Structural comparison and analysis of vibrating screen bearing and common bearing

1 bearing design structure comparison of special vibration bearings: A. The diameter of the rolling body is increased, the length of the rolling body is increased.B. The cage is guided by the outer ring to reduce the force on the roller.C. Use an inner ring to guide the roller and improve the operation of the roller.

1. Comparison of bearing design structure

Special bearing for vibration:

A. The diameter and length of the rolling element are increased. B. The cage is guided by the outer ring to reduce the force on the roller.C. Use an inner ring to guide the roller and improve the operation of the roller.D. Cellular roller bearing cage adopts integral structure, which greatly improves its strength. E. The outer diameter of the self-aligning bearing is designed with oil grooves and oil holes for a good lubrication effect.

Common bearing:

A. The diameter of the roller body and length of the roller body is small. Bearing B. Cage with a roller or inner ring guide. C. The cylindrical roller bearing cage adopts a rivet structure, which is easy to lose and drop the cover.D. The outer diameter of the self-aligning bearing has no oil groove and oil hole, resulting in a poor lubrication effect.

2. Choose materials

Special bearing for vibration:

A. The inner and outer rings and rolling bodies are made of vacuum degassing bearing steel with good fatigue resistance. B. The cage is made of aluminum, iron, and manganese bronze material with high strength, good elasticity, and better wear resistance.

Common bearing:

A. Common bearing steel is used for inner and outer rings and rollers.B. The cage is made of zinc brass with low strength and poor elasticity.

3. Heat treatment mode

Bearing Special bearing for vibration of mining machinery bearing:

A. The inner and outer ring adopts Bayer-Ma mixed quenching or Marstench quenching + high-temperature tempering, with uniform hardness and small internal stress; Good toughness, shock, and vibration resistance.B. Good stability when working within 150C temperature.

Common bearing:

The inner and outer ring adopts ordinary quenching mode, which has poor toughness, poor impact resistance and vibration performance of vibrating screen bearing, and poor thermal stability.

4. Tolerance and manufacturing process

Special bearing for vibration:

A. Manufactured in strict accordance with the P6 precision standard, especially the tolerance of inner and outer diameter is very small.B. Size difference of rolling body ≤0.002.C. The cylindrical roller has a convex outer diameter to avoid stress concentration.D. Rolling surface superfine treatment, high finish.Common bearing:

A. General PO class precision tolerance (part of P6 standard) manufacturing.B. Roller grouping ≤0.005.C. Cylindrical roller without convex practice.D. Some raceways are only polished and have a low finish.

5. Internal clearance

Special bearing for vibration:

The clearance is produced according to the requirements of vibration machinery, and the range is controlled within a small range with good consistency.

Common bearing:

The clearance is generally produced according to the standard group or C3 group, and the clearance of mining machinery bearings is either small, or the range is large and the dispersion is large.

6. Usage effect

Special bearing for vibration:

Low noise, low-temperature rise, good stability, long service life, no early fatigue phenomenon.

Common bearing:

High noise, high-temperature rise, poor stability, short service life, early fatigue phenomenon.

What are the actual differences between domestic bearings and imported bearings?

The size deviation and rotational accuracy of domestic bearings are very close to those of imported bearings. However, there is still a certain gap in dispersion between bearings imported from Germany. Foreign countries have long started to study and use such fine rotation precision index as non-repeatable pulsation, but the research on this level is still blank in China. Two, in the rapid performance level of foreign brand products DMN value of 4 × 106 mm r/min, while the Chinese bearing is only 2 × 106 mm r/min.Three, in the vibration, abnormal sound, and abnormal sound level, Japan has launched silent and ultra-silent bearings, and the vibration extreme level of Chinese bearings is usually more than 10dB different from that of Japanese bearings. Four, in life and on the level in deep groove ball bearing, for example, foreign brand products usually accounting for the life of a life of more than 8 times, up to 30 times more 】 【 on sex for more than 98%, or pursue and host life 】 【 China bearing usually only for the life of a business accounting life of 3 to 5 times, on sex is approximately 96%.?At present, the bearing chemical industry in China has ranked third in the world in terms of the industrial economic scale, but there is still a considerable gap between China and the world's advanced level in terms of product accuracy and technical level. First, China's bearing industry manufacturing concentration is low. In the world's bearing sales of about $40 billion, the world's eight major multinational units account for 75%~80%. Two German units account for 90% of the country's total, five Japanese for 90%, and one American for 56%. And China's tile shaft and other 7 bearing enterprises with annual sales of more than 1 billion yuan, the sales volume only accounts for 28, 3% of the whole industry. China's bearing chemical production technology and process equipment technology development is slow, the CNC machining rate is low, the grinding automation level is low, the country only more than 200 automatic manufacturing lines. Most enterprises, especially the old state-owned enterprises as the main manufacturing force is still the old machinery. Advanced thermal treatment processes and equipment, which are critical to bearing life and reliability, such as adjusted vapor protection heating, double refining, bainite quenching, and other low coverage rates, have failed to make breakthroughs in many technical problems. The development of new kinds of bearing steel, the improvement of steel quality, the development of lubrication, cooling, cleaning, and abrasive tools, and other related technologies can not meet the needs of the improvement of the level and quality of bearing products. As a result, the process efficiency index is low, the homogeneity is poor, the product processing size dispersion is large, the product internal quality is not stable and affects the accuracy, performance, life, and reliability of the bearing. In recent years, the development of bearings in China has made continuous progress, slowly resulting in industrialization. At present, the world-bearing market in China is about 10%, and the sales volume occupies third place in the world. However, compared with the world's powerful countries in bearing chemical industry, there is still a certain gap between Chinese bearings. The primary manifestation is that the proportion of products with high technology, high precision, and high added value is low, and the stability of products needs to be further enhanced and improved.

Three, low efficiency of China's bearing industry development and innovation because most of the enterprises in the innovation system of the construction and operation, development and innovation of investment and talent development level is still low, and industry service-oriented scientific research institutes to the enterprise, the state has no support for research in the general technology and industry, which weakened the ability for industry development. As a result, the industry is weak in basic theoretical research, weak in participation in the formulation of international standards, and less in original technologies and patented products. Now, our design and production technology is basically simulation, decades of consistent system. The low efficiency of product development is shown in that although the matching rate of domestic main engines meets 80%, the matching and repairing bearings of key main engines such as rapid railway passenger cars, middle and high-grade cars, accounting machines, air conditioners, and high level rolling mills are basically imported.