  One of the important stages in the creation of the scientific and technical
foundations for the calculation, design and manufacturing technology of the
lowest heat-conductivity thermal protection from screen-vacuum thermal
insulation (SVTI) is the development of a process for achieving the optimal
vacuum in the SVTI layers, since at this pressure, thermal conductivity through
the SVTI is carried out only due to the radiant and contact-conductive
components. It is proposed to obtain such a pressure in thermal insulation by
using cushioning material in it, which was previously degassed in a separate
vacuum chamber at 370-380 K for 12 hours in order to remove water molecules
from its structure and then replace them with dry nitrogen molecules. These
molecules have 3-4 times less heat of adsorption; therefore they are pumped out
faster. As a result, it becomes possible to accelerate (by 20 hours) to achieve
optimal vacuum in thermal insulation, as well as 11% lower effective thermal
conductivity. The analysis carried out (according to the developed methodology)
showed that the achieved optimal effective thermal conductivity of thermal
insulation in a cryocontainers is determined by 33% of radiant thermal
conductivity and 67% of the contact-conductive component.
