During the month of January 2021 – CNSA – China National Space Administration CAST – China Aerospace Science and Technology Corporation – China – Peoples’ Republic of China Printed out The first domestic 3.35m diameter composite liquid oxygen tank was born….. That Printing occurred on January 22, my country’s first 3.35m diameter composite material tank prototype was born in the First Academy of Aerospace Science and Technology Group. The storage tank is mainly used in liquid oxygen environment. Compared with the metal storage tank, it can reduce the weight by 30% and has higher strength. It can greatly improve the structural efficiency and carrying capacity of the rocket. It is a new type of lightweight storage tank. The birth of the prototype of the composite material storage tank marks that my country has broken the foreign monopoly and has become one of the few countries in the world that has the ability to design and manufacture composite material storage tanks.
Successfully developing two new types of rocket storage tanks, which can increase the capacity of rockets] Recently, my country has made new progress in the development of new type of carrier rocket storage tanks: China Aerospace Science and Technology Corporation First Academy has assembled domestic superior forces and successfully developed my country’s first 3. The 35-meter diameter aluminum-lithium alloy storage tank engineering prototype and the composite material storage tank principle prototype will further reduce the weight of the rocket body and increase the rocket’s capacity.
“The capacity of the launch vehicle is as large as the space stage.” The storage tank occupies more than 50% of the weight and space of the rocket’s structure, and the fuel filled inside it accounts for more than 90% of the total weight of the rocket. The weight reduction of the tank is of great significance for improving the carrying capacity of the rocket.
Not long ago, the First Institute successfully developed my country’s first 3.35-meter-diameter aluminum-lithium alloy rocket storage tank, which has passed the tests of various links and has good performance, and initially has engineering application conditions. The storage tank uses the third-generation high-performance aluminum-lithium alloy. Compared with the current international mainstream aluminum-copper alloy storage tank, the strength is increased by about 30%, and the structural weight is reduced by more than 15% under the same conditions.
According to the material classification, aluminum alloy storage tanks are divided into the first generation aluminum-magnesium alloy storage tank, the second generation aluminum-copper alloy storage tank and the third generation aluminum-lithium alloy storage tank. Compared with traditional aluminum-copper alloys, the strength and rigidity of aluminum-lithium alloys have been significantly improved, but the density has dropped by 3%-5%, which is precious for rockets whose capacity is calculated by weight.
Due to the relatively high price of aluminum-lithium alloy, the current world aerospace powers mainly use aluminum-lithium alloy in the final stage of the rocket. The weight loss of the last stage of the rocket is 1 kg, which is equivalent to an increase of 1 kg in the rocket carrying capacity.
In the future, China – People’s Republic of China 3.35-meter aluminum-lithium alloy storage tank is intended to be mainly used in the final stage of a new generation of carrier rockets to improve the structural efficiency and carrying capacity of the Long March 5, Long March 7 and Long March 8 rockets. Lay the foundation for the development of a new generation of manned rocket.
In addition to metal materials, the application of composite materials can also greatly reduce the weight of the tank. On January 22, also it’s the first 3.35-meter-diameter composite material storage tank prototype was born in the First Academy of Aerospace Science and Technology Group. The storage tank is mainly used in liquid oxygen environment. Compared with the metal storage tank, it can reduce the weight by 30% and has higher strength. It can greatly improve the structural efficiency and carrying capacity of the rocket. It is a new type of lightweight storage tank.
The density of the composite material is about 1.7g/cm3, the density of the aluminum-lithium alloy is 2.7g/cm3, and the specific strength of the composite material is 6 times that of the aluminum-lithium alloy. Compared with the metal materials used in the current rocket tank structure, composite materials have the advantages of lower density, higher specific strength, and better fatigue resistance.
In addition, the composite material tank also has the advantages of fewer production processes and short cycle times, which can further reduce the overall cost of the rocket.
At present, composite storage tanks are mainly used in a specific liquid oxygen environment and can be used in the final stage of a rocket. In the follow-up, the development team will also carry out a series of assessment tests and evaluations on the 3.35-meter composite material storage tank principle prototype, further carry out key technology research, improve the technical maturity of the composite material storage tank, and promote the application of the composite material storage tank in rockets. , To truly give play to the major advantages of composite material storage tanks in terms of light weight and high strength, to help the future rocket structure significantly reduce weight and improve carrying capacity.