Cryogenic butterfly valve is a common valve that works in low temperature medium. NEWLOTOKE solves the problem of thermal expansion and contraction of the valve in a low temperature environment by improving the process and sealing structure. The common low temperature medium includes: the temperature of liquefied ammonia is -269℃, The temperature of hydrogen is -254 ℃, the temperature of liquefied helium is -196 ℃, the temperature of liquid oxygen is -183 ℃, and the temperature of liquefied natural gas is -162 ℃. These media output liquid cryogenic media such as ethylene, liquid oxygen, liquid hydrogen, Liquefied natural gas, liquefied petroleum products, etc., are not only flammable and explosive, but also gasify when the temperature rises, and the volume expands hundreds of times during gasification