(EN) Pipe or conduit (1) is produced by providing tubular preform made of thermoplastic material loaded or not loaded with fibers, arranging preform in open mold and insufflating expansion fluid under pressure into preform, closing the mold when the preform has reached a predetermined degree of radial expansion, extracting the unit from mold after solidification, and attaching or forming connecting and branching pieces at two opposing ends. Production of pipe or conduit comprises providing vibration attenuator in the form of a by-pass conduit portion opening at its two ends into pipe or conduit; providing tubular preform made of thermoplastic material loaded or not loaded with fibers; arranging preform in open mold and insufflating expansion fluid under pressure into the preform while its constituent material is still at a temperature close to its glass transition temperature or softening temperature; closing the mold when the preform has reached a predetermined degree of radial expansion to simultaneously form the walls (1', 2') of circulation pipe, by-pass conduit or pipe portion (2), and solid plate portions (3) connecting the pipe and the pipe portion to formed one piece with walls; extracting the unit (pipe/by-pass pipe portion) from the mold after solidification; and attaching or forming connecting and branching pieces at two opposing ends of the circulation pipe. An Independent claim is also included for a pipe or conduit for circulating gaseous fluid(s) comprising by-pass pipe portion(s) formed in one piece with the wall of circulation pipe and opening, and connecting piece at its two ends.
(FR) La présente invention a pour objet un procédé de fabrication d'un tuyau muni d'au moins un atténuateur de vibrations sous la forme d'une portion de conduit en dérivation.Procédé caractérisé en ce qu'il consiste à fournir une préforme à disposer ladite préforme dans un moule ouvert et à insuffler sous pression un fluide d'expansion dans cette préforme alors que sa matière constitutive est encore à une température proche de sa température de transition vitreuse, à fermer le moule, lorsque la préforme a atteint un degré d'expansion radiale prédéterminé, de manière à former simultanément les parois (1'et 2') dudit tuyau de circulation (1) et de la portion de conduit ou de tuyau en dérivation (2), ainsi que des portions de plaques pleines (3) reliant le tuyau (1) et la portion de tuyau (2), à extraire dudit moule l'ensemble [tuyau (1) / portion de tuyau en dérivation (2) ] après solidification et, enfin, à rapporter ou à former des embouts de connexion et de branchement aux deux extrémités opposées du tuyau de circulation (1).
