High-speed rail has become a dazzling business card for China to go abroad, from 0 to today's 4With 370,000 kilometers, China's high-speed rail has earned a good reputation for both quality and efficiency. And hidden behind all kinds of honors is the "unique stunt" on China's high-speed rail track, not only in China, but also far more than other countries for decades. What's going on here?
At present, China is operating more than 40,000 kilometers of high-speed rail, the most amazing of which is that China's high-speed rail rails can be hundreds of kilometers without seams.
So, are China's high-speed rail rails really as "seamless" as rumored? Why is it called the "unique skill" of China's high-speed rail track?
First of all, it needs to be made clear that it is impossible for an orbit with a distance of several hundred kilometers to be completely free of gaps, at least not with the existing technology. This is related to the production and installation of high-speed rail tracks, after all, it is too whimsical to produce hundreds of kilometers of steel rails at one time.
As a result, most of the rails are prefabricated in quantities of around 2 km, sent to the site and put together. The assembly method is usually welding, and even if there is a high level of skill, it is impossible to achieve a seamless level. So, seamless here means that the weld width is less than 1 mm. It is indeed difficult to see this gap with the naked eye, so Volkswagen has also left the traditional impression of seamless high-speed rail.
We all know that thermal expansion and contraction are natural laws in themselves, and it is impossible for us to act outside the law. Therefore, in the face of this problem, China's railway technicians have also contributed the "Chinese experience":
First of all, the rails are specially treated from the source production. When the blank material of the rail is sufficiently heated, it expands, and then stresses develop inside the machine after it is elongated. This stress is enough to counteract part of the effect of thermal expansion and contraction.
Secondly, during the construction process, the temperature and humidity of the site should be strictly controlled, and the effects of thermal expansion and contraction should be controlled within the range under specific conditions, so as to reduce the adverse effects of this natural law as much as possible.
Finally, after the construction is completed, the railway department will check and fill in the gaps. Every year, the railway department will dispatch and organize regular or random inspection modes to ensure the safety of track operation. In this process, the inspectors will screen the contents of thermal expansion and cold contraction, and repair the problem as soon as it is found, so as to play a role in ensuring quality and quantity.
Usually the normal service life of a rail is about 10-15 years, of course, this life is not a fixed number, if the operation intensity of some sections is extraordinarily large, the speed and weight of the vehicle are high, as well as local climatic conditions and other factors, will affect the service life of the rail.
Take one of the busiest routes in the country, the Beijing-Shanghai high-speed railway, as an example. The Beijing-Shanghai high-speed railway has a speed of 350 kilometers per hour, and the train frequency is very dense, and there is a train from the station in 4 minutes, which is one of the high-speed railways in the world. According to statistics, the average number of trains running on the route per day has reached an astonishing 560+, with a cumulative distance of 1.5+ billion kilometers. As a result, the railways here undergo major refurbishments every two years on average.
At the same time, it has to carry a certain amount of gravity and electricity, so it is very normal for the rail to be worn and deformed. At this time, it is time to declare the end of the rail, and the relevant technicians will also make repairs or replacement after a full inspection.
So the question is again, all these eliminated rails have gone to **?
Some friends may have seen a large number of high-speed rail waste rails will be piled up in the same open space, let them be exposed to the wind and sun, and naturally rot, as if no one has ever managed them. Some of them will be buried directly in situ near the track. The cost of steel rails is expensive, why do you choose to scrap it directly and not use it?
It's not that we don't want to choose the environmentally friendly treatment method of waste utilization, it's true that the scrapped rails have no value. We all know that the manufacture of steel rails uses "unique skills", and if you want to recast them, you need to use the best electrical equipment. In this way, it is necessary to pay a sum of electricity, transportation, manpower and other expenses, which is not cost-effective compared to refining a batch of turtles. Moreover, at present, the domestic secondary rail processing technology is not mature, and the effect of recasting is not as good as the first refining.
Of course, not all the eliminated rails are only directly scrapped, some of the fineness is okay, the quality of the rails will be reprocessed, replaced by ordinary train tracks, freight tracks can also be used. In this way, the degree of damage is larger, and it can be directly sent to the factory for processing and transformation into knives, tools, etc., and the purpose of recycling can also be achieved. Of course, if the damage is too severe, it is not impossible to bury it in situ.
If you have ever been on an ordinary train, you will be impressed by the rickety train journey that accompanies the sound. And the reason why there is such a sound is because there is a certain gap between the ordinary rails. When the train passes through the connection, it makes a different sound due to the size of the gap, which is normal.
WhileThe gaps between the seamless rails are smallerIn addition, the connection is reinforced with very special components, so that when the train passes through the connection again, the noise emitted is small.
If it is an ordinary steel rail, according to the speed of high-speed rail, the sound of the explosion must come and go. Therefore, when taking the high-speed train, although we will hear a certain sound, it is already much smaller compared to ordinary trains.
The second is saving. Compared to ordinary rails, seamless rails remove a large number of rail joints, and the impact on the joints is also reduced. The force is less, the damage to the rail is relatively small, and the loss of raw materials is also small. The annual cost of line maintenance can be reduced by more than 3 percent, and some can save 3 4.
Third, it can increase the comfort of passengers while increasing speed.
The speed of high-speed rail in our country is already at the leading level in the world, but there is still room for improvement. Behind the speed increase is the reliability of the track. Under the guarantee of the track, the high-speed rail can run faster and more stable. Online Literature Awards