The vacuum hard pipe adopts the plug-in male and female joint connection method, and the connection has two forms: clamp locking and flange locking. The pipe interlayer adopts a high vacuum insulation structure, which greatly reduces the consumption of liquid nitrogen during the transportation process. High vacuum hard pipes are used for long-distance transportation of ultra-low temperature media. The pipes are metal in color and have beautiful appearance. They can be widely used for ultra-low temperature media (liquid nitrogen) in aerospace, machinery manufacturing, food processing, biomedical, animal husbandry, scientific research units and other industries. , liquid argon, liquid oxygen, LNG) transportation.