Technological watch

[Problem] To provide a flame-retardant heat insulating tube and a tube joint with excellent flame retardance and heat insulating properties, good pliability, and no evaporative dispersal of condensed moisture. [Solution] A flame-retardant heat insulating tube H1 comprises: a tube body 1 formed from a pliant flexible tube; a foam layer 2 formed from an elastically deformable foam material in which a sheet-like material having an independent foam structure made by extruding and chemically or physically foaming a mixture containing a thermoplastic resin and a flame retardant is laminated so as to cover the outer side of the tube body 1; and a protective layer 3 formed from a protective film laminated so as to cover the outer side of the foam layer. The foam material has a tear strength of 15 N/cm or greater in the extrusion direction of the extrusion molding and a residual elongation of 10% or less after 100% tension in the extrusion direction, as measured in accordance with JIS-K-6767. The tube body 1 and the foam layer 2 are non-adhered and are laminated so as to move freely with respect to each other.