Abstract: A smooth-bore plastic tubing with helical support bead is resistant to collapse and incorporates plural electrical conductors outside of the tubing bore and insulated from ambient, and from one another. The conductors may have a desired relatively high thermal conductivity to tidal air flow within the tubing, while also having a comparatively high thermal resistance to ambient. A method for making the tubing includes extruding a molten thermoplastic ribbon with an elevated plateau portion defining plural conductor-receiving grooves. The plastic ribbon is wrapped to form a tube and plural conductors are embedded in the grooves of the plateau portion. A molten thermoplastic bead is then applied atop the plateau portion providing a smooth-bore unitary flexible tubing structure with both inside and outside surfaces which are substantially free of crevices or recesses which could retain soil or bacteria.

Abstract: A smooth-bore plastic tubing with helical support bead is resistant to collapse and incorporates plural electrical conductors outside of the tubing bore and insulated from ambient, and from one another. The conductors may have a desired relatively high thermal conductivity to tidal air flow within the tubing, while also having a comparatively high thermal resistance to ambient. A method for making the tubing includes extruding a molten thermoplastic ribbon with an elevated plateau portion defining plural conductor-receiving grooves. The plastic ribbon is wrapped to form a tube and plural conductors are embedded in the grooves of the plateau portion. A molten thermoplastic bead is then applied atop the plateau portion providing a smooth-bore unitary flexible tubing structure with both inside and outside surfaces which are substantially free of crevices or recesses which could retain soil or bacteria.