1. Industry status

After more than 70 years of development, my country’s bearing industry has gone through the process of starting from nothing, from small to large, and is currently in a critical period of from weak to strong. In the bearings, the articulated bearings and self-lubricating bearings are highly specialized and also have a certain industrial scale; bearing products such as hydrodynamic and static oil film bearings, suspension bearings, rolling functional components (including mechatronics components) are in the primary stage of development. In the mid-term stage, the technological maturity is not high, and the standardization conditions are not mature enough. It will take time to realize specialized and industrialized manufacturing.

Bearing, as a key mechanical basic part, is an important guarantee for the performance, function and efficiency of the main engine. The bearing industry is a national basic strategic industry, which plays an important supporting role in national economic development and national defense construction. According to 2016 statistics, there are more than 1,700 enterprises above designated size in my country's bearing industry; the annual main business income of the bearing industry exceeds 200 billion yuan. Among them, 160 billion yuan of rolling bearings, 19 billion sets of output; 4.9 billion US dollars of foreign exchange earned by exporting bearings, 5.3 billion sets of exported bearings; 2 billion sets of imported bearings, US$3.4 billion in foreign exchange; It can produce various types of bearings with an inner diameter of 0.6mm and an outer diameter of 11m, with more than 90,000 varieties and specifications. The scale of the bearing industry ranks third in the world, with a market share of about 20% of the global market. The domestic independent supporting rate exceeds 80%. my country imports about 4 billion U.S. dollars of bearings each year, 70% of which are high-end civilian bearings. High-end bearings include four types of rolling bearings, sliding bearings, suspension bearings and bearing functional components. Among them, rolling bearings are the most widely used, standardized and industrialized. Internationally, high-end bearings are basically monopolized by the Swedish SKF company, the German SCHEFFELER company, the Japanese NSK company, NTN company, JTKE company, the United States TIMKEN and other multinational companies whose main products are bearings. Although these companies have set up manufacturing plants and Ru0026D centers in China, the Ru0026D and manufacturing of high-end bearings are located in their own countries, and they have strictly sealed the high-end bearing manufacturing technology.

Second, common problems

In recent years, my country’s bearing development has made continuous progress and gradually formed industrialization. However, compared with the world’s bearing industry powers, my country’s bearings still have a certain gap. The proportion of products with high precision and high added value is low, and the stability of the products needs to be further improved and improved. The common problems of my country's bearings are specifically manifested in:

⑴Insufficient basic theoretical research and common technology research and development.

Basic theoretical research and common technical problems are highlighted, such as the development of weak-supported bearing design and application theory from traditional mechanics and tribology to interface science and technology research, to meet the research of anti-fatigue manufacturing technology for long-life and high-reliability bearing manufacturing. In-depth systematic experimental research on the physical indicators of high-performance bearings, complex extreme conditions (such as load spectrum, coupled friction, heat and temperature rise, and life prediction); research on bearing materials such as bearing steel, ceramics, plastics, nylon, and composite materials, etc. Relatively lagging behind.

⑵The raw materials cannot keep up.

At present, the quality level of bearing steel in my country is relatively low, and its standard level, physical quality and variety are far behind the international advanced level and the needs of the development of the bearing industry. Long-term recurring serious defects in steel have occurred from time to time, and the production, sales and use of low-quality steel have not yet been eliminated. The research and development of new bearing steel grades and the improvement of steel quality are the main problems currently faced by bearing steels.

⑶The company's independent Ru0026D and host supporting capabilities are poor.

The bearing industry currently has a supporting rate of 80% for domestic mainframes, but the supporting and maintenance bearings for important mainframes such as high-speed railway passenger cars, mid-to-high-end cars, computers, air conditioners, and high-level rolling mills are basically imported. This is because most companies are still at a low level in terms of Ru0026D and innovation capital investment, talent development, etc. Research institutes serving the industry are becoming corporate, and the country has no investment in industry-specific technology research, which weakens the research institutes. Functions that are developed for the industry. As a result, basic theoretical research and international standard formulation are weak, and there are relatively few original technologies and patented products.

In addition, the supporting bearings account for a small proportion of the manufacturing cost of the main engine, and the use of lower-priced domestic bearings has little effect on reducing the manufacturing cost of the main engine. The host industry is more willing to avoid risks and choose imported bearings. The lack of pressure and motivation for bearing localization is reflected in the lack of power for bearing localization in the host industry, and it is difficult for the bearing industry to enter the host industry.

⑷The equipment level and process manufacturing technology are relatively low.

Although the precision and performance of bearing special equipment and instruments have reached or approached the international advanced level, there is a big gap between the precision retention and performance stability and the international advanced level. The CNC rate of car processing and the automation level of grinding processing in my country are not high, and there are only more than 200 automatic production lines in the country. Most enterprises, especially the old state-owned enterprises, still use traditional equipment as the main production force. Advanced heat treatment processes and equipment that are critical to bearing life and reliability, such as controlled atmosphere protection heating, double refinement, and bainite quenching, have low coverage.

The development of manufacturing technology in my country's bearing industry is slow. The research and development of processing, lubrication, cooling, cleaning and abrasives and other related technology cannot meet the requirements of improving the level and quality of bearing products. This results in low process capability index, poor consistency, large product processing size dispersion, and unstable product internal quality, which affects the accuracy, performance, life and reliability of the bearing.