Thermally insulated hose and method for producing the same

摘要

A method for producing a thermally insulated hose comprises the steps of (A) forming a cylindrical inner layer from a soft resin; (B) winding a reinforcing member helically around the inner layer for uniting with each other to form the flexible inner tube comprising the inner layer and the reinforcing member, the reinforcing member comprising a hard resin and protruding from an outer periphery of the inner layer toward an outer surface of the hose; (C) winding a thermal insulating elastic strip around an outer side of the flexible inner tube for forming a thermal insulating layer; and (D) forming an outer layer on an outermost side of the thermal insulating layer for immobilizing or fixing the thermal insulating strip. In the step (C), the thermal insulating strip is helically wound around the outer side of the flexible inner tube with arranging a cross section of the strip substantially parallel to the axial direction of the hose, with opposing or facing adjacent lateral edges of the strip to each other, with forming a gap between an inner surface of the strip and an outer surface of the inner layer, and with compressing the strip in a thickness direction at a contact area in which the strip contacts with the reinforcing member. The thermally insulated hose suppresses the protrusion of the inner layer inside the hose and the increase of flow resistance of a fluid even when the hose is bent.