An improved insulated transmission line for the transfer of cryogenic media is disclosed comprising: a tubular heat shield, including at least three concentric, radially separated, corrugated metallic tubular members, that provides a first annular space between two of the tubular members wherein a multiple...http://www.google.es/patents/US4303105?utm_source=gb-gplus-sharePatente US4303105 - Insulated transmission line for cryogenic media
