A method of manufacturing self-pierce rivets from a length of wire comprises separating the length of wire to form a plurality of slugs, each slug defining a head end and a tail end. The method further comprises forging a plurality of rivets from the slugs, each rivet having a head formed from the head end of a slug and a tip formed from the tail end of that slug, the head and the tip of the rivet being separated by a shank which defines a longitudinal axis, the rivet having a bore which runs substantially longitudinally through the tip and at least part way along the shank. For each of the plurality of rivets, the method comprises performing a machining operation on the tip the rivet or on the tail end of the slug from which the rivet was forged.

A method of manufacturing self-pierce rivets from a length of wire comprises separating the length of wire to form a plurality of slugs, each slug defining a head end and a tail end. The method further comprises forging a plurality of rivets from the slugs, each rivet having a head formed from the head end of a slug and a tip formed from the tail end of that slug, the head and the tip of the rivet being separated by a shank which defines a longitudinal axis, the rivet having a bore which runs substantially longitudinally through the tip and at least part way along the shank. For each of the plurality of rivets, the method comprises performing a machining operation on the tip the rivet or on the tail end of the slug from which the rivet was forged.

Piece to be crimped on a support, comprising a bearing head and a shaft comprising a crimping section intended to be deformed when crimping the piece, the crimping section comprising a first hollow section adjacent to the bearing head and a second section adjacent the first section, the second section being configured to deform outside of the piece into a crimping flange for crimping the piece on the support, and the first section is configured to deform inside the hollow space of the shaft into a clearance flange in order to limit stresses on the support when crimping the piece.

Piece to be crimped on a support, comprising a bearing head and a shaft comprising a crimping section intended to be deformed when crimping the piece, the crimping section comprising a first hollow section adjacent to the bearing head and a second section adjacent the first section, the second section being configured to deform outside of the piece into a crimping flange for crimping the piece on the support, and the first section is configured to deform inside the hollow space of the shaft into a clearance flange in order to limit stresses on the support when crimping the piece.

A wire mesh rivet (13) is provided which is used to produce a wire mesh isolator (11) in a bore (9) of a substrate such as a heat shield (7) for a vehicle exhaust system. The rivet (13) comprises a unitary wire mesh structure (19) which has a collar (15) and a shank (17). The collar (15) has a higher density than the shank (17), e.g., the collar (15) has the density of the finished isolator (11). The rivet (13) is formed into the finished isolator (11) by compressing the shank (17) to form a second collar, while restraining the original collar (15) from substantially changing its shape. The rivet (13) can include a metal insert (23) which prevents the wire mesh of the finished isolator (11) from experiencing high levels of compression when the substrate is fastened to its supporting structure. The rivets (13) can be carried by a dispensing strip (31) and can be formed into the finished isolator (11) using forming equipment (39) whose dimensions are compatible with the limited space available with some substrates.

A method of forming a fastener includes inserting a blank precursor into a bore of a forming die having an enlarged bore portion, applying a first axial compression force to the blank precursor, and forming a cold-worked head section and an enlarged shank portion on the blank precursor corresponding to the enlarged bore portion. The enlarged shank portion has a nominal shank portion extending therefrom. The method additionally includes inserting the nominal shank portion into a bore of a final reduction die, applying a second axial compression force to the enlarged shank portion, and urging the enlarged shank portion into the bore of the final reduction die. The method includes reducing a cross-sectional area of the enlarged shank portion by approximately 2 to 5 percent to form a cold-worked shank section.

A method of forming a fastener includes inserting a blank precursor into a bore of a forming die having an enlarged bore portion, applying a first axial compression force to the blank precursor, and forming a cold-worked head section and an enlarged shank portion on the blank precursor corresponding to the enlarged bore portion. The enlarged shank portion has a nominal shank portion extending therefrom. The method additionally includes inserting the nominal shank portion into a bore of a final reduction die, applying a second axial compression force to the enlarged shank portion, and urging the enlarged shank portion into the bore of the final reduction die. The method includes reducing a cross-sectional area of the enlarged shank portion by approximately 2 to 5 percent to form a cold-worked shank section.

A wire mesh rivet (13) is provided which is used to produce a wire mesh isolator (11) in a bore (9) of a substrate such as a heat shield (7) for a vehicle exhaust system. The rivet (13) comprises a unitary wire mesh structure (19) which has a collar (15) and a shank (17). The collar (15) has a higher density than the shank (17), e.g., the collar (15) has the density of the finished isolator (11). The rivet (13) is formed into the finished isolator (11) by compressing the shank (17) to form a second collar, while restraining the original collar (15) from substantially changing its shape. The rivet (13) can include a metal insert (23) which prevents the wire mesh of the finished isolator (11) from experiencing high levels of compression when the substrate is fastened to its supporting structure. The rivets (13) can be carried by a dispensing strip (31) and can be formed into the finished isolator (11) using forming equipment (39) whose dimensions are compatible with the limited space available with some substrates.

A method of forming a fastener may include inserting a blank precursor into a bore of a forming die having an enlarged bore portion. The method may further include applying a first axial compression force to the blank precursor, and forming a cold-worked head section and an enlarged shank portion on the blank precursor corresponding to the enlarged bore portion. The enlarged shank portion may have a nominal shank portion extending therefrom. The method may additionally include inserting the nominal shank portion into a bore of a final reduction die, applying a second axial compression force to the enlarged shank portion, and urging the enlarged shank portion into the bore of the final reduction die. The method may also include reducing a cross-sectional area of the enlarged shank portion by approximately 2 to 5 percent to form a cold-worked shank section.

A method of forming a fastener may include inserting a blank precursor into a bore of a forming die having an enlarged bore portion. The method may further include applying a first axial compression force to the blank precursor, and forming a cold-worked head section and an enlarged shank portion on the blank precursor corresponding to the enlarged bore portion. The enlarged shank portion may have a nominal shank portion extending therefrom. The method may additionally include inserting the nominal shank portion into a bore of a final reduction die, applying a second axial compression force to the enlarged shank portion, and urging the enlarged shank portion into the bore of the final reduction die. The method may also include reducing a cross-sectional area of the enlarged shank portion by approximately 2 to 5 percent to form a cold-worked shank section.