Care about Fengxian big and small things, pay attention to "Shanghai Fengxian" in one hand!
With the Beijing Winter Olympics approaching
The Olympic torch "flying" is becoming more and more familiar
In addition to the elegant and beautiful appearance
There are also a lot of "black technology" inside.
As a global first
The Olympic torch is made of carbon fiber composite material
The "flying" shell must not only be resistant to fire and high temperatures
It should also be able to be used in extremely cold weather
"If you touch it, the 'flying' feels good, the weather is so cold, but it doesn't feel cold when you hold it." Lin Shengbing, general manager of Sinopec Shanghai Petrochemical Innovation Research Institute, highlighted its distinctive shell material when showing "Feiyang", "The carbon fiber composite material used in the shell is only about a quarter of the quality of steel, but the strength is 7 to 9 times that of steel." ”
Shell: Carbon fiber "knit sweater" molded
Dating back to June 2020, Lin Shengbing suddenly received a notice from his superiors: at the request of the Winter Olympic Organizing Committee, a carbon fiber shell was developed for the torch to "fly".
"The 'Xiangyun' torch for the 2008 Beijing Olympics is a metal shell that is stable but cold to the touch." Lin Shengbing said that the Winter Olympic torch relay is the time of severe cold, the traditional metal material is not good, carbon fiber composite materials can avoid this problem, "carbon fiber quality is only about a quarter of steel, but the strength is 7 to 9 times that of steel." The light weight of carbon fiber and the characteristics of not breaking the solid, especially suitable for the production of torches. ”
It is understood that the Beijing Winter Olympic Organizing Committee for the whole society to open the collection of torch design, a total of 182 pieces of applied works were received, and finally after repeated selection and review by experts in design and combustion, a torch shape combining internal and external streamers was finally determined, named "Flying", becoming the torch design scheme for the 2022 Winter Olympic and Paralympic Winter Games. In accordance with the guiding ideology of the Beijing Winter Olympics Green Olympics and the Science and Technology Olympics, it is determined that hydrogen energy and carbon fiber will become the direction of efforts for the torch of the 2022 Winter Olympics.
Due to the industrial advantages of Shanghai Petrochemical's carbon fiber production base, Sinopec entrusted the manufacture of carbon fiber torches to Shanghai as a major mission. Huang Xiangyu, deputy general manager of Sinopec Shanghai Petrochemical Company, introduced that the torch adopted three-dimensional weaving technology, which is a technological breakthrough in carbon fiber molding, and each black tow contains 12,000 carbon fiber filaments. After three-dimensional weaving, it is finally woven into a torch shell like a "knitted sweater", and no seams and pores can be seen, and the whole shape is integrated.
△ Torch support team in the assembly of "flying"
The seemingly simple shell of the torch has a lot of fun on the inside. Lin Shengbing said that the torch is mainly divided into three parts: the outer streamer, the inner streamer and the hydrogen combustion device. The outermost layer is called the "outer streamer", which is composed of carbon fiber and a synthetic material of high-temperature flame retardant resin, and there is also an inner shell "inner streamer", which is made of aluminum alloy, and the combustion port is between the inner shell. Inside the flare, there is also a small hydrogen storage bottle and pressure reducing valve that can be easily disassembled for ventilation. "Pressure reducing valves and hydrogen storage cylinders are world problems, 'flying' use of hydrogen combustion, the need to reduce the pressure in the bottle from 420 kg force / square centimeter to close to the standard atmospheric pressure (about 1 kg force / square centimeter) at a distance of a tiger's mouth, and maintain a stable flow, the difficulty can be imagined."
Accident: Flames burst out when the torch shell is displayed
In contrast, the "innate inadequacy" of carbon fiber composite materials has plagued Lin Shengbing for a long time, and even almost gave up this "black technology".
It is understood that carbon fiber is like a layer of cloth, which requires "skeleton" support to be better shaped, but the general resin and carbon fiber composite materials can only withstand a temperature of about 200 degrees Celsius, and the flare burning port must withstand a high temperature of more than 800 degrees Celsius.
Where to find high-temperature resistant materials has become a top priority. They first approached a professor who studied ceramic materials, and suggested coating ceramics on carbon fibers. After several exchanges and arguments, Lin Shengbing and other team members believed that this was "neither feasible nor good-looking." Unexpectedly, a company in The "neighbor" of Shanghai Petrochemical, Jinshan Ergong District, finally found a solution.
Kubei Chemical (Shanghai) Co., Ltd. is a team of only 14 employees, they spent 5 years to develop the third generation of polysilazane resin, can withstand the high temperature of 1200 degrees Celsius, and the hydrogen combustion temperature is generally 800 degrees Celsius, fully up to meet the requirements of the torch shell material.
"Traditional high-temperature resistant materials are generally inorganic, no adhesion can not form a coating, polysilica azide resin is an organic and inorganic composite material, both to ensure high temperature resistance, but also good adhesion." Liu Zhangyou, general manager of Kubei Chemical, said that the initial solution was to add polysilica nitrogen resin coating to ordinary resin and carbon fiber synthetic materials, due to heat conduction and other issues can only be pushed back and forth, and finally determined by the polysiliconazane resin directly with carbon fiber synthesis of new materials scheme.
However, when Lin Shengbing reported to the Organizing Committee of the Winter Olympics with a new material shell, he encountered an accident. After the torch was ignited, two flame points appeared in the shell, and a small flame burst out, and there was a phenomenon of foaming and cracking. In the face of this "rollover", their comprehensive judgment is that the shell molding temperature is not in place, and the speed is too fast to produce thermal expansion and contraction. After continuous debugging, Lin Shengbing's team has overcome the major problems of carbon fiber composites that are resistant to combustion and high temperatures, and the "flying" Olympic torch was also successfully born.
△ Lin Shengbing and "Flying"
Soon, a total process integrating torch shell, inner streamer, combustion system, tinder lamp, terminal inspection, and delivery of products was quickly established and operated in five major bases such as Shanghai, Beijing, Jiangsu, Guangdong and Hebei. In the face of tight time, heavy tasks and high requirements, Shanghai Petrochemical maintains close communication with the Beijing Winter Olympic Organizing Committee and the Sinopec Winter Olympic Office, from the shape, edges, corners, colors, and assembly of the components of the inner and outer streamers of the torch, to the hydrogen cylinder samples, hydrogen control valves, combustion effects, and then to the appearance of the tinder lamp, internal structure, ease of operation, etc., all of which have been improved in deepening the design and optimizing the process, while ensuring the progress of the torch mass production.
On September 22 last year, Shanghai Petrochemical officially delivered 115 propane torches, tinder lamps, ignition rods and other peripheral products to the Winter Olympics Organizing Committee, successfully completing the first batch of mass production tasks delivered by the Winter Olympics Organizing Committee.
The future: Torch technology can be used in cars
Within 3 months of the development of the torch shell, Shanghai Petrochemical and its cooperative team have overcome a number of technical problems one by one, forming a one-stop solution from carbon fiber production, composite material preparation to product terminal application, solving the two major problems of carbon fiber composite materials with high temperature resistance, combustion resistance, and the use of hydrogen as fuel, and forming three highlights of scientific and technological innovation: First, the production of torch shells with carbon fiber composite materials has become the world's first. Second, carbon fiber composite materials have achieved normal use in hydrogen combustion environments with combustion temperatures greater than 800 degrees Celsius. Third, the weight is more than 20% lighter than the aluminum alloy shell, showing the characteristics of "light, solid and beautiful".
According to reports, carbon fiber is a new material with excellent mechanical properties, known as "black gold", the king of new materials in the 21st century, with broad application fields and development prospects, but carbon fiber has strict technical barriers. Previously, it was only mastered by a few developed countries such as Japan and the United States, but after long-term research and development, Shanghai Petrochemical became the first enterprise in China and the fourth in the world to master the industrialization technology of carbon fiber large tow.
Shanghai Petrochemical began to carry out carbon fiber technology research in 2008, undertook to complete a number of national "863" and "973" plans and major projects of Sinopec, formed an innovative ability from the primary silk, pre-oxidation, carbon fiber to composite material industry chain, has independent intellectual property rights complete sets of technology, Sinopec has applied for 274 carbon fiber related patents, authorized 165, ranking first in China and third in the world. At present, Shanghai Petrochemical is fully promoting the construction of projects such as 24,000 tons/year raw silk, 12,000 tons/year 48K large-tow carbon fiber, and 100-ton high-performance carbon fiber, and accelerating the construction of carbon fiber and composite material industry clusters.
The development process of carbon fiber composite materials for the torch shell of the Winter Olympics is both a challenge and an opportunity. Huang Xiangyu said that whether it is aircraft, or photovoltaic heat field materials, as well as wind power blades of offshore wind power, there will be carbon fiber applications in the future. "With the lightweight of new energy vehicles, car shells can also be made of carbon fiber, and the development of carbon fiber and carbon fiber composite materials in the mainland is very fast, and in the future, we are still studying the torch, and this material can be used in other more useful places."
Source: Shanghai Regional Trend
Editor: Wu Yan
end