Thermal insulation for rotatable coaxial tubes - protects rotational elements from fluid in tubes over wide temperature range

摘要

The radial thermal insulator is for a rotational element (1) between the ends of two coaxial tubes (2,3) for fluid transfer. It has a hollow cylinder (4) of insulating material, which fits into a housing (5) between the tubes and rotation elements. A stagnant vapour of the fluid provides extra insulation, when trapped in the space (6) between the cylinder and elements. Frontal insulation is provided by rings (7) of insulating material, clamped between the tubes and rotational elements. The insulation thermal balance could be improved by circulating nitrogen at ambient temperature inside the rotational elements.