The liquid stored in the liquid nitrogen tank has the characteristics of lower boiling point, larger expansibility, stronger asphyxiation and strong oxidizing properties. When in contact with the human body, it can cause frostbite on the skin and eyes of humans. When a small amount of cryogenic liquid leaks or leaks inside the valve, the temperature at the point of absorption will absorb the heat in the surrounding environment, and the leak will quickly dew condensation and even freeze. If you receive high heat from the surrounding environment or absorb a large amount of ambient energy, the volume will expand due to rapid gasification, which can easily cause overpressure and explosion of the container or pipeline. Therefore, during use, you should always check if the tank is normal and maintain it regularly.