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Gear is an important basic component of industrial equipment, most of the mechanical transmission of complete sets of equipment are relying on gear. The gear industry is basically composed of three parts: vehicle gear, industrial gear and gear equipment. Vehicle gear products include vehicle gears and vehicle transmission assemblies. The application fields include all kinds of automobiles, motorcycles, construction machinery, agricultural machinery and military vehicles, among which traditional automobiles are the main ones, accounting for about 50% of the total vehicle gears. Industrial gear products include industrial general, special, heavy-duty gear transmission products, application collars. Areas include marine, mining, metallurgy, aviation, power and so on; gear equipment manufacturing industry includes gear machine tools, cutting tools, measuring tools, test equipment, gear lubrication and sealing, etc., in the gear industry as a whole accounted for a lower 7. At present, there are more than 1000 gear manufacturing enterprises in China, and more than 300 backbone gear manufacturers. The output and sales of key enterprises account for more than 75% of the whole industry, with a large number of enterprises with output value of more than 100 million yuan, and full market competition. As far as market demand and scale of production are concerned, China has become a world gear manufacturing country worthy of the name. China's gear industry continued to grow in production scale from 2010 to 2014, the total industrial output increased from 682,000 tons to 3,019,000 tons. In 2015, affected by the economic downturn, the output of China's gear industry fell back to 2,740,000 tons in 2016. The total industrial output value of China's gear industry increased from 145 billion yuan in 2010 to 224.5 billion yuan in 2014, with a cumulative growth of 54.83% and an average annual growth of 13.71%. There was a slight decline in 2015, with a total output value of 220 billion yuan and a total output value of 230 billion yuan in 2016, ranking first in the world, an increase of 4.5% over the same period last year. Domestic gear market concentration is low, single enterprise occupies a small share of the overall market. Each enterprise focuses on different application areas. At present, the comprehensive technical level of product quality, product design, process development, manufacturing equipment and testing in domestic gear industry is backward. On the one hand, the middle and low-end product overcapacity, homogenization of vicious competition; on the other hand, high-end product capacity is insufficient, automotive, construction machinery, high-speed rail, coal machine and robot reducer and other high-end gear transmission devices still need to rely heavily on imports 9. But at the same time, the innovation and R&D capabilities of domestic enterprises are constantly improving, and the substitution effect of high-end products is becoming more and more obvious.