Bearings are important and key basic components in the equipment manufacturing industry, which directly determine the performance, quality and reliability of major equipment and host products, and are known as the "heart" components of equipment manufacturing. After years of development, my country's bearing industry has formed a considerable scale. The output value of the national bearing industry in 2010 was about 130 billion yuan, ranking third in the world. Although the development scale of my country's bearing industry has been very large, most of them are concentrated in the low-end, and in the field of high-end bearing manufacturing, there is still a considerable gap between my country and developed countries. Wang Quanqing, secretary general of China Bearing Industry Association, also made it clear that the development speed of China's high-end bearings has not kept up with the development speed of mainframes. For example, my country has mastered the high-speed EMU technology with independent intellectual property rights, but the supporting bearings still basically rely on imports. At present, most of the high-speed bearings produced by domestic bearing companies can only meet the needs of trains with a speed of 150 kilometers to 180 kilometers, while the high-speed bearings of European and American countries can meet the needs of trains with a speed of 350 kilometers to 400 kilometers per hour. The high-speed rail bearings basically rely on high-priced imports.