Large aluminum extrusion technology needs to be broken

China's development and production of new high-speed trains, ships and large aircraft requires a large number of high-end materials as a support, in which the production of large aluminum profiles is undoubtedly an important part. Therefore, as soon as possible, we have developed and developed high-tech aluminum extrusion and tensile straightening equipment with high technology content in China, and accelerated the promotion of our own large-scale aluminum production advanced equipment, which is currently placed in a very urgent need in China's equipment manufacturing industry. task.
Modern industry urgently needs important materials such as large aluminum materials. The so-called large aluminum profiles mainly refer to aluminum profiles with a width of more than 800 mm and a circumscribed circle diameter of more than 250 mm and a delivery length of more than 12 meters. Large aluminum profiles with complex cross-sections and lengths of up to 60 meters are multi-functional assemblies that can achieve the same precision of general machined products and are used as critical structural materials for critical parts of machines. Since one large aluminum profile can replace the wide thin-walled aluminum structural member that was previously made up of two or more aluminum profiles, the structure of the mechanical component becomes more reasonable and a complete component surface is obtained. At the same time, the production of large aluminum profiles can increase extrusion productivity and save money. Therefore, the production of new high-speed trains, ships and large aircraft, if there is no large aluminum profiles for support, its so-called "Made in China" is empty talk.
More importantly, large-scale aluminum profiles are not only necessary for the production of new high-speed trains, ships, and large aircrafts, but also important materials that are urgently needed in various aspects of China's current rapid economic development. The manufacture of modern transportation equipment such as subways and light rails is also an important material for the development of modern weapons production and aerospace industries in national defense construction.
In recent years, due to the development of China's subway, high-speed trains, urban light rail, aerospace and other industries, it has been used in aircraft siding, high-speed train bodies, subway and urban light rail trains, maglev train bodies, containers, shipboard siding, etc. The demand for thin-walled, wide-width, high-precision, and complex sections of aluminum alloy profiles has grown rapidly. In the “Eleventh Five-Year Plan”, the state will invest 200 billion yuan in the construction of subways in major cities in China. The newly manufactured subway cars will all be made of extra large aluminum alloy profiles. According to relevant forecasts, in the next five years, the demand for China's extra large aluminum profiles and aluminum alloy profiles will be over 150,000 tons. If imported from abroad, the price will be around US$10,000 per ton.
Large-scale extrusion equipment has a huge market potential Although there are many kinds of extrusion machines, internationally, extruders with a size of more than 50 MN are generally called large-scale extruders, and extruders with a capacity of 80 MN or more are called heavy-duty extruders. At present, the total volume of large-scale extrusion presses produced at home and abroad exceeds 40 sets.
The equipment of large-scale extrusion presses abroad is basically produced before the 1970s. Most of them are hydraulic presses and the technology is backward. In recent years, four to five large extruders have been added to the United States, Germany, Japan, and South Korea. There are seven large-scale aluminum extrusion production lines currently in operation in China, and five large aluminum extrusion press production lines are under construction. In the past five years, China will also build more than 10 large-scale extrusion press production lines. Large extrusion presses in China have a potentially huge market, and they are also showing rising demand in foreign countries. For countries such as Southeast Asia and India, the development of large-scale extruders is still in its infancy, but it is estimated that there will be several large-scale extruder production lines within 10 years.
The research and development of large-scale aluminum profile extrusion equipment has always attached great importance to the developed countries. Many countries have successively established relevant technology research centers. Among them, the famous BCTiin extrusion technology center in Germany, the KENTCKY extrusion technology center in the United States, and the UK HYDRO extrusion technology research and engineering technology research center. China started late in the research and development of large aluminum extrusion technology and equipment. Not only did the research methods and methods lag behind foreign countries, but they also lag behind foreign countries in terms of human and financial resources. In the research and development of large-scale aluminum profile equipment, the China Heavy Machinery Research Institute (Xi'an Heavy Machinery Research Institute) and Taiyuan Heavy Industry Co., Ltd. are at the leading position in China.
From 1999, China Heavy Machinery Research Institute began to develop China's first hydraulic transmission 10,000 tons extrusion production equipment, put into production on July 1, 2002. In 2003, the institute began to develop the 125MN hydraulic double-acting aluminum profile extrusion production line, which has been installed and commissioned. This has made a major breakthrough in the development of large aluminum profile technology and the development of new products. So far, the institute has designed and developed more than 30 5MN to 125MN copper/aluminum extrusion machine production lines. For example, the 125MN double-acting aluminum extrusion press developed by the company is the world's largest direct-drive aluminum extrusion press, and the 40MN double-acting copper extrusion press production line is currently the largest copper extrusion production line in Asia. At the same time, the Institute also developed 55MN, 60MN, 100MN and 125MN aluminum extrusion production line rear processing equipment, and 150MN aluminum extrusion production line is under development.
The foundation of technology research and development and industrialization needs to be established. The large-scale aluminum profile isothermal extrusion technology process is the basis for the control of high-performance large-scale aluminum profiles. Our country has studied and established the calculation formulas of heating energy, heating power and air cooling capacity required for large-scale aluminum profile extrusion chambers; established a three-dimensional thermal coupling finite element analysis model for the extrusion process of large aluminum profiles, and solved the reasonable boundary conditions. The problem is dealt with; the isotherm extrusion speed curve for large wide plates and large profiled fin tubes is proposed; and the technical route for the isothermal extrusion process of large aluminum profiles based on temperature and speed control is proposed.