China's 10000 ton aluminum profile extrusion press breaks German technology monopoly
The successful manufacture of 10000 ton hydraulic double acting aluminum profile extruder breaks the technical monopoly and blockade of Germany, and improves the production capacity of China's large-scale and complex cross-section thin-walled aluminum profiles.
High speed rail has become a business card of China on the international stage, and the localization of China's high-speed rail is inseparable from a key equipment domestic 10000 ton aluminum profile extrusion machine.
(the wall panel of China's high-speed railway carriage is a complex hollow structure with a length of 25m. The 10000 ton aluminum extruder can extrude this part into an integral structure at one time, with light weight, high strength and long fatigue life.)
Modern high-speed railway must meet the requirements of light weight and long structural strength and fatigue life at the same time in order to achieve energy saving and consumption reduction and meet the durability.
To achieve these two seemingly contradictory design goals, it is necessary to realize the large-scale and one-time forming of structural parts, which all depend on aluminum extrusion process.
What is the difficulty of R & D and manufacturing of 10000 ton aluminum extruder? What technological breakthroughs have China made in the localization of the equipment?
The first breakthrough lies in the design of extruder body mechanism and hydraulic system.
The hydraulic system of 30 MPa working pressure was used earlier in China, and the variable pump and proportional valve technology were used earlier in domestic large-scale hydraulic equipment. The old-fashioned hydraulic system uses quantitative pump, and the speed control relies on the speed regulating valve. The hydraulic pump has been running at high power, and a large amount of high-energy hydraulic oil directly flows back to the oil tank, resulting in high energy consumption and high heat output of the system. With the use of variable displacement pump, the open-loop speed regulation of variable displacement pump can meet the design requirements at high speed. At low speed, the energy consumption of variable pump combined with proportional valve is greatly reduced. The newly designed hydraulic system makes the ten thousand ton extruder adapt to various working conditions with low energy consumption and low cost.
The second technological breakthrough lies in the breakthrough of control technology and extrusion process.
The core of aluminum extrusion process is to ensure isothermal extrusion. The outlet temperature of the whole extrusion process must be maintained at 500 ℃ according to the aluminum alloy grades, and the temperature fluctuation shall not exceed plus or minus 5 degrees. If the temperature is too high, the aluminum material can not maintain the solid flow state, and even melt into liquid, resulting in process failure; if the temperature is too low, the aluminum material fluidity will be reduced, which will cause the extrusion process to be stuck or even damaged. At the same time, the temperature of aluminum material should not fluctuate too much, which will lead to the quality problems of extruded profiles, such as surface defects, strength reduction and so on.
（3） Aluminum extrusion press is not the bigger the better, 10000 tons can meet the needs of high-speed rail and large aircraft
After the successful localization of the 10000 ton aluminum extruder, China has manufactured a larger tonnage aluminum profile extruder, and soon broke through the 36000 ton seamless high alloy steel pipe vertical extruder technology, which can be said to drive the development and progress of China's extruder industry.
