The ice surface precision of the national snowmobile sled center track reaches millimeter class, making ice and repairing ice is completely “manual work”.
Xinhua News Agency, Beijing, May 22: more than two years of hard work in the “war epidemic”-China’s first snowmobile sled track ice making Records
Xinhua News Agency reporter Zhang Xiaoxiao
more than two months ago, the national snowmobile sled center in Yanqing division of Beijing Winter Olympic Games achieved the first one-time success of ice making at the track during the tight stage of epidemic prevention and control in China. For more than two years, there has been a lot of accumulation and a lot of success in the “war epidemic”, which has become a special experience in the construction of Beijing Winter Olympics project.
Unremitting preparation
The national snowmobile sled center has built China’s first snowmobile sled track. The track is 1975 meters long, with 16 corners in total, the 11th of which is the unique 360-degree swing bend in the world. The players accelerate from the departure area to slide into the track. The ice speed exceeds 130 kilometers per hour. Every surface and angle of the track are related to the performance of the game and even the safety of the players.
Beijing-controlled Beijing Olympic company undertakes the construction task of “dream interpretation” of the national snowmobile sled center. After more than two years to overcome difficulties, the “dragon” lying on the small Haituo Mountain realized “building bones and veins” before the Spring Festival this year-the keel of the track was successfully closed, the main concrete structure of the track was sprayed, the refrigeration piping system of about 120000 meters track has been installed. With the completion of the hoisting of the largest ammonia separator in similar projects in the world, the “heart of Dragon Tour” is successfully put in place, and the construction of the track ushered in the core node-“Dragon vein congestion”.
Lin Jianfeng, project manager of Shanghai Baoye, construction party of national snowmobile sled center, introduced that “congestion” means injecting liquid Ammonia refrigerant into ammonia liquid separator through technical means to prepare for ammonia refrigeration in the next stage. The national snowmobile sled center adopts a natural working medium ammonia direct evaporation refrigeration system with high refrigeration efficiency and environmental protection, which can safely and stably transport refrigerant liquid ammonia to the whole track pipe system, using the highly efficient evaporation and heat absorption characteristics of liquid ammonia, the track temperature is continuously reduced to reach the pre-condition of ice making.
The ammonia refrigeration system of the national snowmobile sled center is extremely difficult to design and construct, and the ammonia charging capacity of the track of similar international projects is about 40 tons to 70 tons at a time, the national snowmobile sled center is filled with about 80 tons of ammonia at a time, which shows the difficulty of refrigeration.
Promote the construction of
national snowmobile sled center in “anti-epidemic” to fill many technical gaps in China. The venue construction takes a “small step” forward, and behind it, it may take a “big step” to cultivate independent ability “.
“The core content of how to integrate and set parameters after foreign equipment is bought is very complicated.” Li Changzhou, deputy general manager of Beijing control Beijing Olympic Company, introduced that the national snowmobile sled center has 54 independent refrigeration sections with complicated pipeline connections. After the system is installed, it takes experienced refrigeration engineers at least 6 months of repeated monitoring and debugging to adjust the new track refrigeration system to the best state. The Chinese team participating in the debugging for the first time is still in the exploratory stage.
In order to ensure the success of ice making and repairing in the national snowmobile sled center, the German team cooperated with the Chinese team to debug the equipment on site since September 2019. Due to the approaching of the official pre-certification time of the track, the national snowmobile sled center has become the only non-stop project of the Beijing Winter Olympics project this Spring Festival, and hundreds of builders stick to their posts. However, the sudden epidemic disrupted the construction plan. German commissioning personnel left on January 30, and the commissioning work of refrigeration automatic control system and main equipment suddenly fell into a deadlock. In order not to affect the progress of the project, the Chinese team tried every means.
With the support of Beijing Winter Olympic organizing committee and Beijing Major Project Office, Beijing control Beijing Olympic company quickly set up a network communication platform. The German team agreed to use remote connection, telephone communication, video conferences and other methods guide Chinese operations, and the cooperation process lasts for one month. Luo Jin, general manager of Beijing control Beijing Olympic Company, introduced that due to the time difference between China and Germany, the two sides held several late-night meetings until 4 a.m. Beijing time. “The track has a large amount of ammonia filling, and the management and control are difficult. The German team initially thought that remote debugging is difficult to achieve. We communicated repeatedly, coupled with the trust from the previous running-in, the German team finally monitored the progress in real time through the large screen of the headquarters, and opened the modules in the automatic control system to us one by one.”
From February 10, the Chinese team spent 18 days injecting 4 batches of about 80 tons of liquid ammonia into the refrigeration system. Since February 25, ammonia pump will inject liquid ammonia into the track for continuous cooling and cooling, which initially appeared sherbet. Wu Wei, chief designer of the German side of the national snowmobile sled Center track, specially recorded a video to congratulate: “This is the most smooth debugging I have ever seen. The most remarkable thing is that it was realized through remote control when the epidemic was raging.”
The new team appeared
When the outside world focused on the track covered with sherbet, it was rarely known that, behind the appearance of “Ice Dragon”, the efforts of a group of ice and snow “sweeping monks” are still indispensable. The ice surface precision of the national snowmobile sled center track reaches millimeter class, making ice and repairing ice is completely “manual work”. According to the construction needs, the project specially established China’s first snowmobile sled track ice-making and repairing team. On March 1st, the team officially started the ice making and repairing operation, which was the hero who achieved the success of the track ice making in 10 days.
Wu Qiang, ice-making Director of National snowmobile sled center, introduced that ice-making and ice-repairing on the track not only requires the physical fitness, height and strength of personnel, but also requires excellent construction finishing technology. This project was screened from 200 people layer by layer, and 10 outstanding talents were sent to Pyeongchang, South Korea for training in last November. During the spring festival this year, the project further hired a foreign ice maker to carry out ice making and repairing exercises with the chinese ice maker team before the formal ammonia refrigeration by using yanqing natural temperature in 3 shifts and nights, lay the foundation for formal operations.
Li Kaishun, the captain of the ice-making and ice-repairing team of the national snowmobile sled center, introduced that his work was mainly divided into four items: track ice-making, ice-repairing, and daily cleaning. Ice making uses a special ice-making water pipe nozzle to spray thousands of water mist in each refrigeration unit to ensure the whole ice-making forming of the track; Ice making is to fill the ice-water mixture with scraper to the racing car into the bend, key positions such as the exit bend and the ice is easy to fall off. After the ice is frozen, it is slowly sprayed with water to protect it, forming a whole with the surrounding ice surface; Repairing ice means holding a special repair of skates weighing 20 Jin, keep repairing the formed sliding surface on the track with even force; Daily cleaning means strengthening the maintenance and inspection of the ice surface and cleaning the ice mass and snow Frost of the track.
Li kaishun introduced that the ice temperature of the snowmobile sled track is controlled at about minus 10 to 16 degrees celsius. The team members need to step on the “crampons” and wear thick down jacket homework to check the thickness of the ice layer, the face is almost stuck on the ice. Due to the high labor intensity, the body sweats a lot, and the experience of “two days of Ice and Fire” makes people very uncomfortable.
In this case, the ice-making and ice-repairing team made 7000 square meters of ice in 10 days, and mastered the judgment of ice-making conditions from the frost form of the track, by controlling the temperature to realize a series of ice making techniques such as “micro-finishing” on the ice surface, the ice making technology becomes more and more skillful.
Li Shuping, chairman of Beijing Olympic control company, introduced that although the pre-certification of the national snowmobile sled track originally planned for middle March this year was postponed due to the epidemic, Beijing Winter Olympic builders still completed the ice-making task of the track as originally planned, this special test will add infinite confidence to the subsequent construction of the venue.