How to check the pressure of a cryogenic storage tank

The structure of the cryogenic insulation container of the cryogenic storage tank is different from that of ordinary pressure vessels. Its structure adopts a unique vacuum jacketed structure, that is, according to different design requirements, different thermal insulation methods are used between the closed metal liner and the outer shell, so that the interlayer reaches a certain Degree of vacuum. The particularity of this type of cryogenic storage tank in terms of structure and use determines that this type of product is a technology-intensive product. Its manufacturing and production process involves comprehensive technologies such as cryogenic materials, cryogenic welding, and cryogenic adsorption. Therefore, its corresponding The inspection and testing technology requirements are different from ordinary pressure vessels.
 
Because its structure is a fully enclosed vacuum interlayer container and the medium is a cryogenic liquid, the inner liner cannot be directly inspected, which adds to the difficulty of inspection. In order to ensure the reliability of the inspection, it is necessary to carry out a systematic analysis of the factors that affect safety during the operation of the cryogenic storage tank, understand the internal laws of the cryogenic storage tank, and determine the content and method of the inspection of important links and key factors.

For liquid nitrogen tanks, when filling liquid nitrogen, it takes 48 hours to evaporate to return to the normal state. The time required for a high-quality liquid nitrogen tank to return to normal state can be shortened to twelve hours, and the evaporation loss can be reduced by 50%. First of all, someone must be responsible for management, use and maintenance. The storage room of the liquid nitrogen tank must be well ventilated. If the liquid nitrogen tank is stored in a closed room, the evaporated nitrogen will stay in the room, causing hypoxia and suffocating. The liquid nitrogen tank should be handled with care, and no other objects Collide.

Second, when filling liquid nitrogen for the first time, or when the inside of the liquid nitrogen tank is dry, check it first to see if there is a depression outside the tank, whether there is any foreign matter in the tank, and whether the base is exactly firm. Liquid nitrogen filling is a pressure injection method, which is to open the liquid valve from a large liquid nitrogen container and connect a hose to directly fill the liquid nitrogen. The other is to directly use the funnel pouring method, which requires the end of the funnel to be slightly separated from the neck tube, so that the liquid nitrogen vapor can escape from the gap between the funnel and the container, otherwise the liquid will overflow from the funnel, which will not only increase the liquid Nitrogen evaporates and frostbite can occur.