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Liquefied natural gas (LNG) is the hydrocarbon fuel with the fastest growing demand in the world today, which in turn leads to an increased need for additional facilities for its production and transportation. This requires the development of new technologies that are cost-effective, safe, and reliable. For transporting cryogenic products such as LNG, modern pipeline technology allows for the use of either flexible hoses or rigid pipes. The former is limited to short-distance loading and unloading due to high costs and insulation limitations, whereas rigid pipes can be used for longer distances. With the advent of modern low-temperature submarine pipeline designs, the effective transportation distance for LNG can reach 32 km. Currently, the design and construction methods for rigid cryogenic pipelines involve creating an insulating space around the pipeline to create a low-pressure and vacuum environment, which provides relatively good insulation effects; however, the operation and maintenance costs of such systems are high. In such cases, the pipeline must be submerged underwater or even laid beneath the seabed, which raises issues related to thermal expansion and contraction of the pipe, compression, and structural stability. Pipelines for transporting materials at low temperatures, especially frozen materials, require high mechanical stability as well as the desired thermal insulation properties; at the same time, they should have a simple structure to keep maintenance and installation costs relatively low. A new design for liquefied natural gas (LNG) pipelines embodies these desired characteristics. An air-inlet gel insulating layer is added inside the \"tube within a tube\", creating an annular space between the product pipe and the outer sleeve; this annular space is then partially filled with highly efficient fine porous or ultra-fine porous materials. In most cases, the pressure acting on the annular space comes from external environmental pressures; thus, this system serves a supporting function and provides thermal insulation, eliminating the need to use expensive alloys or expansion membranes to create and maintain a vacuum.