Process for producing a multilayer pipe by expansion and multilayer pipe produced by said process

• Main Authors: ALVES PINHEIRO, Gustavo, SILVEIRA E SILVA, Julio Marcio, EBELING, Timo, DA SILVA PERDIGAO, Hezick, AMES, Jochen Peter, DA SILVA PENNA, Antonio Wagner, GRANHA GIORGINI, Danielle
• Format: Patent
• Language: English
• Published: 07.04.2022
• Subjects: AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKINGWITHOUT ESSENTIALLY REMOVING MATERIAL; BLASTING; COMBINED OPERATIONS; ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HEATING; JOINTS OR FITTINGS FOR PIPES; LIGHTING; MACHINE TOOLS; MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES,OTHERWISE THAN BY ROLLING; MEANS FOR THERMAL INSULATION IN GENERAL; MECHANICAL ENGINEERING; MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVINGMATERIAL; METAL-WORKING NOT OTHERWISE PROVIDED FOR; OTHER WORKING OF METAL; PERFORMING OPERATIONS; PIPES; PUNCHING METAL; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; THERMAL INSULATION IN GENERAL; TRANSPORTING; UNIVERSAL MACHINE TOOLS; WEAPONS

PROCESS FOR PRODUCING A MULTILAYER PIPE BY EXPANSION AND MULTILAYER PIPE PRODUCED BY SAID PROCESS A process for producing a multilayer pipe (1) by expansion, wherein the multilayer pipe (1) comprises at least one external layer made from an outer pipe (10) consisting of a carbon manganese steel alloy and an internal layer made from an inner pipe (20) consisting of a corrosion-resistant alloy, the inner pipe (20) having an elastic return smaller than the elastic return of the outer pipe (10) when both are deformed, and an and an external diameter smaller than the internal diameter of the outer pipe (10). The process for producing the multilayer pipe (1) comprises a mounting step (34) between the pipes (10, 20), wherein the inner pipe (20) is inserted inside the outer pipe (10), and at least one mechanical expansion step (36) of the inner pipe (20) and the outer pipe (10) together, comprising moving a mandrel (2) relative to the mounted pipes in the longitudinally direction, with the mandrel (2) being located internally in the inner pipe (20), wherein at least part of the mandrel (2) has a greater external diameter than the internal diameter of the inner pipe (20). Wherein in the expansion step, the mandrel (2) causes deformation on the wall thickness of the inner pipe (20), and the expansion of inner pipe (20) causes elastic deformation on the wall thickness of the outer pipe (10).