A new bright spot for the application of aluminum in medium and low speed maglev trains

Maglev trains are the crown jewels of rail passenger vehicles. They can be divided into two types according to the speed of operation. They are high-speed and medium-low speed, the speed of the former is ≥400km/h, and the speed of the latter is ≤160km/h. Beijing's first low-speed magnetic levitation S1 line began operations at the end of 2016; China's first medium- and low-speed maglev train started production on November 23, 2015 in Changsha, Hunan Province, and is expected to be put into operation in the first half of 2016. This magnetic suspension train line is part of Changsha’s maglev engineering project. It starts from Changsha High Speed ​​Rail South Station in the west and Huanghua Airport in the east. It is an elevated line with a total length of approximately 18.5km. It was started construction in June 2015 and was completed at the end of the year.

The advantages of medium and low speed maglev trains

After the concept of magnetic levitation train was put forward in the 1920s, scientists have devoted themselves to solving the problem of high-speed train operation by means of magnetic levitation in the past 100 years. In recent years, it has been quiet, zero-pollution, high-capacity, low-cost and a series of The advantages and disadvantages of the development of medium- and low-speed maglev trains have been highly sought after. At present, only a very few countries in the world such as China, Germany, and Japan have mastered this technology. China National University of Defense Science, Zhuzhou Electric Locomotive Co., Ltd., Zhuzhou Electric Locomotive Co., Ltd., Maglev Transportation System Center, Southwest Jiaotong University, and China Railway No. 2 Institute have done a lot of pioneering work in the research and development of medium and low speed maglev trains, making China’s overall technical level in this area the world’s Leading.

No noise, no obvious vibration

Because the maglev train is not in contact with the track and is floating, it will fly in the "air" of 10mm away from the track without friction. Therefore, there will be no obvious vibration and it will be stable and stable. It can meet the needs of standing, without noise and without disturbing people. Like a bird flies past, breeze blowing.

No electromagnetic radiation pollution, harmless to human body

The principle of operation of the magnetic levitation train is to use electromagnetic force to counteract the gravity of the earth. Through the automatic control system, the distance between the body and the track is always maintained at about 10 mm. The magnetic force is concentrated in this 10mm space. Once out of this space, the magnetic force will return to a level approximately equal to that of the earth's magnetic field and will not cause any damage to the passengers and the surrounding residents. The Institute of Electrical Engineering of the Chinese Academy of Sciences conducted six-and-ten-round third-party tests on the electromagnetic radiation of Beijing Maglev train. The test results showed that the DC magnetic field strength was less than normal when watching TV. The AC magnetic field intensity was less than that of using electric shaving. The effect of the knife on the human body.

China's chief maglev technologist and Professor Chang Wensen of the National University of Defense Technology stated in February 2011 that “Beijing S1 magnetic levitation line will be installed and the visual electromagnetic radiation measurement equipment will be installed in the carriage. Passengers can intuitively 'see' magnetic field strength. Therefore, people are assured of the safety of the maglev train."

The cost is lower than that of the subway and can be entered into the residential area

The construction cost of medium and low speed maglev trains is not only lower than that of subways, but also lower than that of subways. It can be entered into residential communities and can be revolved around the building. It can pass through the bottom or middle of high-rise buildings, and there will be no soot emissions after operation. Wheels and rails rub and it is very quiet to run. At the same time, adopting a special "hooking track" design can ensure that the train does not derail or roll over. The overall cost of construction is 1/3 and 1/4 lower than that of the railway and the medium-traffic light rail. The minimum turning radius is only 50m and the climbing ability is very strong. It can run freely around buildings or mountains.

Wide application prospects

The medium and low speed magnetic levitation trains take into consideration the environmental protection, economy and safety, and have a broad application prospect in the densely populated cities for the environmentally friendly landscape resorts. There are many companies in China that can manufacture medium and low speed magnetic suspension trains, and two cities are building medium and low speed maglev train lines.

The first Chinese magnetic levitation train manufactured by Zhuzhou Electric Locomotive Co., Ltd.'s magnetic levitation transportation system center quietly drove off the production line on January 20th, 2012. The three sections were grouped with a sleek body and decorated with a “Chinese Red” waistline. Soft seats, floor-to-ceiling windows, dark stainless steel handrails. The warm colors are so large that the interior of the cabin is like the cabin of a large civil aviation passenger plane. This medium and low speed maglev train has a maximum design speed of 100km/h and a maximum capacity of about 600 passengers. On November 23, 2015, a medium- and low-speed maglev train debuted in Changsha and began to be commissioned. It is planned to put into operation in the first half of 2016 on the Changsha Maglev line, which will be the first line officially operated in China.

Beijing Beikong Group has already determined that the fourth-generation medium and low-speed magnetic levitation trains developed by its subsidiary Beijing maglev will be the leading products as early as 2012, and will enter the future urban rail transit market in China. Beijing S1 low-speed magnetic levitation line can be put into operation in late 2016, with six cars in a group. The maximum speed of Beijing's medium and low speed maglev trains is 160km/h, but for safety reasons, the actual speed is controlled at 40km/h~60km/h, and each carriage contains about 100 passengers, and the distance between the stations is 1.5km~2km.

Mid-low speed maglev train aluminum application emerging market

In 2016, Beijing and Changsha in China each have a medium and low-speed maglev train. The first phase of the Beijing S1 line is 10.236km, and the Changsha line is about 18.5km. It requires a total of about 200 cars, and the quality of aluminum procurement for each car is 10t. About 2000t aluminum consumption. The width of the S1 line cabin is 3m and it is 15m long. It is wider and shorter than the average subway train. As the medium and low speed magnetic levitation trains have a series of advantages, they are the best solutions for the most cost-effective environmental protection and excellent urban rail transit construction. Therefore, after the Changsha line and the Beijing S1 line are put into operation, China may be in the country for the next 15 years. The city set off a wave of construction of low-speed magnetic levitation passenger lines, which became a new bright spot for aluminum applications. China has completely mastered the design, manufacture and management of all aspects of medium and low speed maglev trains. The high-speed rail has become China's gold business card on the international market, and the medium-low speed magnetic levitation will soon become the second gold business card of China’s vertical and horizontal international market.

The structure of the low- and medium-speed maglev train can be made of aluminum alloy, steel, stainless steel or composite materials. However, the friction stir welding of extruded aluminum profiles has the highest cost-effectiveness and investment efficiency. The large extruded section and the high-speed railcar body are used. In the same way, there are more than a dozen companies in China that can produce in batches. The used plate alloys are 5005, 5052, 5083, 6061, and the profile alloys are 5083, 6061, 6N01, 6063, 6082, 7N01, 7003, etc. The amount of each car is less than 500kg, mainly ZL101 and EN-Al10Si8 alloys.

In 2003, China's high-speed maglev trains with the introduction of German equipment and technology began operations in Shanghai's Pudong. They not only operate safely until now, but also fully grasp, digest and absorb the introduced technologies, and have innovatively possessed high-speed, medium-low speed and low-speed intellectual property rights. Maglev train production and control technology.

The Chinese magnetic levitation train is driven by a strong magnetic field and suspension generated by permanent magnets at its bottom. This type of permanent magnet is made of a ferromagnetic material Nd-Fe-B (Nd-Fe-B) alloy, which is a rare earth metal, and China is a rare earth. The hometown, which accounts for more than 80% of the world's total reserves, provides a strong resource support for the development of Nd-Fe-B alloys.

At present, there are three types of magnetic levitation in the world: the German conductive type, the Japanese superconducting type, and the permanent magnet type in China. The first two types require the use of electricity to generate maglev power. The permanent magnet suspension in China uses special permanent magnetic materials and does not require any other power support. In any case, the body and the rails do not touch each other, while the German and Japanese technologies do not have electricity, the body Contact with groove track. However, no matter what kind of technology is used for magnetic levitation, permanent magnets are indispensable, but only in number, how long the rails are, and how long permanent magnets are.