Corrosion-resistant steel pipe for underground heat transport - is wrapped in aluminium foil bonded and coated with polymer resistant to heat and hydrolysis

摘要

Steel pipe for underground heat transport has a multilayer corrosion protection coating, at least one layer of which consists of Al foil, wraped around and bonded firmly to the outer surface of the pipe by an adhesive of temp. and hydrolysis-resistant polymer and coated with a temp.- and hydrolysis-resistant polymer. Both the adhesive and coating can consist of poly(amide)imide or polysulphone, whilst the coating can also consist of polyethyersulphone. The coating prevents diffusion.