Selection of liquid nitrogen pipeline materials

304, combined with foam insulation for safety and low cost, is the best choice. Care must be taken with the safety of vacuum tubes, as a leak can lead to a physical explosion. Moreover, it has a high cost and requires regular vacuum pumping checks.

So what are the advantages of vacuum insulation tubes?

In other words, its insulating effect is the best available today, allowing for a reduction in the vaporization rate of liquid nitrogen.

This post was last edited by AZHPB on 2018-3-25 at 19:56. Price: If high-performance insulation materials such as the Italian Furless or German Ales flexible insulation materials are used for the external insulation of 304 bare tubes, the cost per meter is approximately half lower than that of vacuum tubes； Construction difficulty: Although both 304 bare tubes and insulation materials are installed on-site, the construction difficulty is still lower than that of vacuum tubes. This is because 304 bare tubes only require piping to be arranged on-site before welding; the flexible insulation materials from Italian firms such as Fulus or German firms like Ales make on-site installation much easier compared to traditional PIR insulation. While vacuum tubes go through processes such as welding, insulation paper wrapping, and heating for vacuuming at the manufacturing plant, no changes can be made once they have been prefabricated. The joints at both ends of these tubes (which still require separate insulation material) usually have only about 150 mm of expansion allowance, and this amount is often not sufficient for on-site use. To ensure reliability, responsible vacuum tube manufacturers typically send people to the site for testing before prefabrication. Even so, it is generally difficult to ensure that all vacuum tubes in a project can be welded successfully, as this involves many factors such as design drawings, errors in civil engineering work, and inaccuracies in equipment positioning. Maintenance and operation after deployment: When flexible insulation materials such as those from Italian company Fullex or German company Alus are used, and if construction is carried out in strict accordance with the manufacturer’s guidelines, the product can remain in use for over 10 years; in the absence of external damage, virtually no maintenance is required ； Although, in theory, vacuum tubes offer the best insulating performance among all existing insulation systems, the issue of static evaporation rate means that after several years of operation, as this rate increases, the insulating effect gradually deteriorates. The direct consequence of this is frequent overpressure releases by the pipeline’s safety valves. Usually, it becomes necessary to re-evacuate the space inside the tubes after a few years of use; however, even after such re-evacuation, it is difficult to restore the insulating effect to its original level. After all, the need to re-evacuate the space indicates that the insulating material inside the jacket has become damp. I hope the above experience will be helpful to you.

The liquid nitrogen pipelines in chemical plants are generally made of austenitic stainless steel, while the liquid nitrogen storage tanks are jacketed pressure vessels.

:Lol, I have 304 pipes