Composite electrically heated tubing product

Claim 1

An armored, deformable composite tubing product of generally uniform construction throughout its length which is adapted for use as a temperature-controlled, sampling tubing and which comprises: a. a flexible, heat conductive sampling line means which has a passageway through it for conveying a fluid whose temperature is to be controlled; b. at least two electrical heating lines helically wound around said sampling line means in engaged, heat transferring relation, said lines being in generally symmetrically disposed relation with respect to the outer peripheral surface of said sampling line means; c. continuous, flexible polymeric strand means wound around said sampling line means and said heating lines for maintaining said heating lines in their helically disposed, engaged, heat transferring relation with said sampling line means; d. a layer of fibrous filler material disposed in encompassing and contacting relation around said sampling line means and said heating lines along the length thereof; e. a layer of flexible tape helically wound around said layer of filler material in encompassing and contacting relation to provide a moisture impervious barrier around said filler layer; f. a flexible, polymeric layer encompassing and contacting said tape layer and providing a protective and moisture resistant barrier; g. a flexible, metallic protective layer comprised of corrugated metal armor disposed around and contacting said polymeric layer throughout its length; and h. a flexible, polymeric outer sheath encompassing and contacting said metallic layer with said outer sheath generally engaging the corrugations of the metal armor and mechanically interlocking with the corrugations.