Method of manufacturing a flexible pipe

The invention concerns a method for making a flexible conduit comprising a flexible metal frame (1) consisting of a helical winding spires with a clamping profile made from a stainless steel strip with a clamping profile; the method consists in a thermal treatment for temper-hardening the metal constituting the frame, carried out during or after winding the frame. The steel can be austenitic and cooling brings about hardening by martensitic transformation; alternatively the steel is austeno-ferritic and heating brings about hardening of the ferritic phase.