High-speed rail is a successful example of independent innovation in mainland China, and it is also an important embodiment of new quality productivity. Since entering the "14th Five-Year Plan", the mainland high-speed railway has been leading the world while constantly developing new technologies and new products. The CR450 science and technology innovation project, led by China Railway Group, is currently in full swing, which is a key measure to aim at the future development of high-speed rail and strive to achieve higher-speed commercial operation of high-speed rail.
The CR450 scientific and technological innovation project mainly includes the CR450 EMU and the 400 km/h high-speed rail line, bridge, tunnel and other infrastructure technology innovation. At present, the CR450 EMU prototype is being intensified, when will the prototype be off the assembly line? What new technologies are needed to speed up the train? How to drive the development of related industries in the future? Let's walk into the front line of CR450 EMU prototype development↓↓↓
The reporter visited the CR450
Critical Systems Laboratory
Walking into the CR450 EMU key system laboratory, Zhao Hongwei, chief researcher of China Academy of Railway Sciences, first took reporters to see the digital model of the braking system. In her opinion, from 350 kilometers per hour to 400 kilometers per hour, the most critical technology is not whether you can run, but whether you can stop, stop steadily, and stop accurately.
Zhao Hongwei, chief researcher of China Academy of Railway Sciences: The most important thing is the braking system, which must be able to stop. Our technical indicators at the top level require that the braking distance should be consistent with the braking distance of the CR400 at a speed of 350 kilometers per hour, and it is also 6500 meters, so the braking capacity of the entire train must be improved.
The reporter then simulated the brakes, and the big screen showed that the brake cylinder data module had changed significantly, and these data came from hundreds of real test records.
The red-hot disc in the lens is the brake disc being tested, which gradually turns from black to red and then from red to black under simulated extreme working conditions, and the temperature difference can exceed 700°C. The data accumulated in the process of change will be stored in the "smart brain", build a digital model, and perform precise calculations on each link.
Zhao Hongwei, chief researcher of China Academy of Railway Sciences: Our original CR400 braking response time was about 2.3 seconds, this time we want to increase it to 1.7 seconds, and the response time can further compress the braking distance of the train.
Not just the braking system, but also each critical system, from traction power, network control to safety monitoring, has its own unique digital model. Through accurate calculations, they found the key to making the train run fast, stop steadily, and consume less energy, that is, to make it more "physical" and "lighter".
Zhao Hongwei, chief researcher of China Academy of Railway Sciences: If we want to reach a speed of 400 kilometers per hour, we still need to increase the power. The CR400 has a traction power of 9,600 kW, and on the CR450 it reaches 11,000 kW, and we have also reduced the weight of the train.
A number of technical breakthroughs
Make sure the CR450 reaches speeds of up to 400 kilometers per hour
According to the known test data, the weight of the CR450 body is about 10 tons, which is about 12% less than the existing CR400 Fuxing train, and the running resistance and energy consumption indicators are reduced by 20% respectively, and the braking performance and traction efficiency are increased by 20% and 3% respectively, so that the train can achieve an operating speed of 50 kilometers per hour and reach a speed of 400 kilometers per hour under the condition that the braking distance, noise and energy consumption indicators remain unchanged.
The CR450 EMU prototype will roll off the assembly line within the year
Since September 2017, the Fuxing China Standard EMU CR400 train has been put into operation on the Beijing-Shanghai high-speed railway, which has created a new benchmark for the world's high-speed rail operation speed with a speed of 350 kilometers per hour.
What new breakthroughs will be achieved in speed for the CR450 EMU under development, and when will it be rolled off the assembly line?
In the welding workshop of CRRC Changqing, rows of manipulators are welding CR450 bogies. The staff told reporters that the factory mainly uses manipulators to replace manual welding, and the production efficiency has been greatly improved.
Xie Yuanli, Chief Operator of CRRC Changke Co., Ltd.: The improvement of speed level has put forward higher requirements for our welding process. The manipulator welding completely follows the walking path edited by the program, which avoids the interference of human factors and can achieve no defects.
The development of the CR450 EMU is another technological breakthrough on the basis of the CR400 Chinese standard EMU of Fuxing, which rolled off the assembly line in 2017, and the running speed of the train will be increased from 350 kilometers to 400 kilometers.
Since the launch of the CR450 scientific and technological innovation project in 2021, it has successively completed the development of 17 prototypes of new technology components, carried out 57 scientific research tests on the CR400 comprehensive inspection train, and created a new record of 453 kilometers per hour for a single train on the open line of EMUs, 891 kilometers per hour for relative rendezvous and 840 kilometers per hour for tunnel rendezvous.
Zhang Dayong, Director of the Science and Technology and Information Technology Department of China Railway Group: At present, important progress has been made in the technological innovation of railway infrastructure with a speed of 400 kilometers per hour and the construction of a comprehensive test section at a higher speed. The CR450 EMU has completed the formulation of top-level indicators and overall schemes, and has entered the stage of construction design and prototype development, and the prototype will be rolled off the assembly line within the year, and a series of tests will be carried out.
Lightweight new materials are widely used
Leverage the high-speed rail market
In the interview, the reporter learned that according to the design requirements, the CR450 EMU will increase its speed by 50 kilometers per hour, and the environmental protection indicators such as noise and energy consumption will not exceed the CR400 Fuxing train. This is due to the application of lightweight and efficient new materials and technologies, and at the same time, these new materials and technologies have also driven the continuous upgrading of the high-speed rail industry chain.
The permanent magnet motor of the CR450 traction system is the first time that it has been applied to a high-speed rail train in commercial operation in mainland China. In the working state, it is charged at more than 2,000 volts, the number of revolutions per second is 100 revolutions, and the power is increased by 14.5%.
Not only permanent magnet materials containing rare metals, CR450 EMUs use a large number of carbon fiber composite materials, which are lower than traditional materials, and have a series of technical index advantages such as light weight, high strength, high temperature resistance, fatigue resistance, etc., which provide an optimal solution for the lightweight of high-speed trains, which is conducive to vehicle weight reduction, speed increase and energy consumption.
Nie Ying, senior chief designer of high-speed EMUs of CRRC Sifang Co., Ltd.: I am holding a carbon fiber gasket in my hand, like CR450, and carbon fiber materials are used in the equipment compartment and obstacle remover, which can reduce the weight by 30% compared with traditional materials, so that the body is lighter and the energy consumption is lower.
From 300 kilometers per hour, 350 kilometers to 400 kilometers per hour, high-speed rail trains are running faster and faster, not only for the materials to be replaced more and more new, but also to drive the continuous upgrading of the entire high-speed rail industry chain. At present, the mainland has built characteristic industrial clusters closely related to high-speed rail in Changchun, Jilin, Qingdao, Shandong, and Zhuzhou, Hunan.
Zhao Hongwei, chief researcher of China Academy of Railway Sciences: Like some host companies, they have a lot of supporting suppliers around them, forming an industrial scale of 100 billion yuan. The development of high-speed rail still has a very big role in driving the entire industrial transformation and upgrading.
Data Insights:
"Number" refers to high-speed rail scientific and technological innovation
The CR450 EMU, which will be rolled off the assembly line within the year, will promote the technological innovation of high-speed railway EMUs and infrastructure systems in mainland China, and fill the gap in the technical standard system of high-speed rail with a speed of 400 kilometers per hour. The relevant scientific research results obtained by the CR450 scientific and technological innovation project will be widely used in the field of railway construction and operation, further enhance the self-reliance and self-improvement ability of railway science and technology, and consolidate and expand the world's leading advantage of mainland high-speed rail technology.
Scientific and technological innovation makes high-speed rail run faster and faster. Relying on independent innovation, China's high-speed rail has continuously improved the level of infrastructure and mobile equipment, step by step, and has experienced a speed of 200 kilometers per hour, 250 kilometers per hour, 300 kilometers per hour, and 350 kilometers per hour, and will open a new era of 400 kilometers per hour in the future. Today, China's high-speed rail has formed the world's largest operating network, with a domestic mileage of more than 45,000 kilometers, and the Fuxing has reached 31 provinces, autonomous regions and municipalities, and more than 2.2 billion people have traveled on the Fuxing.
Scientific and technological innovation has brought the distance closer and closer. From 350 kilometers per hour to 400 kilometers per hour, the speed is 50 kilometers per hour, which is not only a number, but also a reconstruction of the distance between time and space. Studies have shown that the best travel distance is within 800 kilometers for EMUs with a speed of more than 200 kilometers per hour, about 1,200 kilometers for high-speed trains with a speed of 300 kilometers per hour, and 1,600 kilometers for high-speed trains with a speed of 400 kilometers per hour.
Scientific and technological innovation makes the industry bigger and bigger. A Fuxing EMU is composed of more than 500,000 parts, covering many technical fields such as machinery, metallurgy, materials, power electronics, chemical industry, information control, computers, precision instruments and so on. China Railway Group has taken the lead in establishing a railway science and technology innovation alliance covering key enterprises, universities and scientific research units inside and outside the railway industry to achieve deep integration of production, education and research. From R&D, manufacturing, to the coordinated development of the whole chain of operation and maintenance services, 260 independent technical systems have been formed, and more than 100 core enterprises and more than 2,100 affiliated enterprises have designed and produced EMU parts, covering more than 20 provinces, autonomous regions and municipalities in China.
(Reporter Zheng Liankai, Wang Chaopeng, Wang Wei, Wu Gang, Zhejiang Station)
Source: CCTV news client