The invention relates to construction and can be used when applying heat insulating on metal pipes. The task of said invention is to provide removal of moisture between insulation and pipe for reducing pipe corrosion and increasing its life time wherein preserving all functional heat insulating properties. The task is solved using a convection cavity designed in the form of separate toroidal ducts closed in their upper part linked in the pipeline bottom part by a longitudinal channel with an aperture filled with steam supply heat insulation. Using such invention provides for automatic moisture removal between the insulation and the pipe during 0.5-1 day. It leads to increase of pipeline life time preserving its all functional heat insulating properties.
