According to reports, now Japan, Germany and other countries have already phased out 335MPa of low-grade steel,cast bronze with strength in the 500MPa, 600MPa grade steel bar above. However, there are low intensity use, poor performance and below 335MPa steel still two-thirds.
Many facts indicate that the strength of steel products in China is low, and poor performance problems to be solved to improve the quality of steel urgency of the situation.
In recent years,bronze bushing the rapid development of high-speed railway, the speed EMU reached the international advanced level, but the domestic requirements of the wheel speed can not keep up, so far all from Japan, Germany imports. China's development of "large aircraft"dry bushing design is very advanced, fuel-efficient 15%, attracted worldwide attention, has started to bulk orders, but the aircraft engines,plain bearing landing gear, hydraulic tubes and the various components involved in iron and steel materials, and now all imported. Many facts indicate that the strength of steel products in China is low,sleeve bushing and poor performance problems to be solved.
Reality: improve the quality of the situation urgent.
DU bushing Liu Haimin Metallurgical Industry of China Center for Economic Development Deputy Director, while his other capacity as members of the Group of China Metallurgical Chamber of Commerce. Are in the steel industry, long-term study of Chinese steel industry, tracking the pace of the world's iron and steel enterprises, so that Liu Haimin of China's bushing steel industry has a more clear understanding.
Central "second Five-Year" plan proposal, the future should focus on the development of advanced equipment manufacturing, adjust and optimize the raw material industries, and promote the manufacturing sector to grow stronger; brass bushing to foster the development of equipment manufacturing, including high-end strategic emerging industries, basically completed Quick railway and highway networks and so on.
Mould guide plate "The rapid industrial upgrading and development of the requirements of the steel industry is not the production or variety, plastic bushing but the quality and performance. Germany, Japan, the United States and other countries to become powerful and advanced equipment manufacturing power, the key is they have to produce quality steel products a solid foundation. In China, the quality of steel was the development of modern industrial system can not keep up. "Liu Haimin recently said of the author. He believes that improving the quality of steel is China's "second five" most important iron and steel industry.
In recent years, rapid development of high-speed railway, the speed of EMU has reached international advanced level, equivalent to the aircraft take-off speed, requiring the wheels must be free of defects, does not allow "accidental." But the wheel has not kept pace in China-made high-speed rail speed requirements, so far all from Japan, Germany imports.
According to reports, the current set of wheels of a moving vehicle over 300 kg, import prices as high as 60,000 yuan, according to tonnage of 20 million per ton, higher than 15 times made common wheels. EMU carriages of high strength, high toughness steel plate has not yet developed, the vehicle manufacturer can not wait, had to replace the aluminum alloy plate, the cost is very high.
China's development of "large aircraft" design is very advanced and optimized by dynamics models, saving 15%, attracted worldwide attention, has started to bulk orders. However, aircraft engines, landing gear, hydraulic tubes and the various components involved in iron and steel materials, and now all imported.
Wind turbine gears, bearings, although the speed is not high, not "high, fine, sharp" products, but they are in the desert, plateau, or 80 meters above the sea runs high altitude, difficult to repair, bad parts equal to the retirement of an entire small unit. Therefore, the wind power equipment required quality of steel must be absolutely stable and uniform to ensure that 20 years without maintenance. However, unstable quality of domestic steel, the user can not use, basically rely on imports.
China's gear steel, bearing steel, tool steel is low overall surplus of high-end imports, domestic steel manufactures life expectancy is only 1/2-1/3 of imported goods. According to the machinery industry statistics, annual consumption of imported luxury gear about 50 billion U.S. dollars, equivalent to one-third of industry sales of gear.
China has a large railway bridge span, light structure, corrosion resistance, long life direction, but the traditional low-alloy bridge board has not meet the requirements of modern bridge construction.
Reinforcing steel is the largest amount of variety. Use of low-grade steel in the event of an earthquake will cause the collapse of housing crushing. The last century 120 million people worldwide die by the earthquake, which killed 60 million people in China. The last two years of Wenchuan 8 earthquake killed 7 million people, Chile 8.8 earthquake killed 700 people, New Zealand 7.2 earthquake zero death. Liu Haimin that this is directly related with the quality of steel.