A riveting system, for use in mechanically linking adjacent workpieces, including a rivet having a height greater than a sum of thicknesses, measured along a line of riveting, of the workpieces being linked, so that the rivet can pass fully through the workpieces. The system also includes a riveting die, which may be a separate product. The die includes a protrusion extending from a peak toward a transition point; and a trough having a trough surface. The trough surface includes a trough inner wall, extending from the transition point to a trough bottom, and a trough outer wall, extending from the trough bottom to a trough outer edge. The technology also includes computerized systems for comparing a load-displacement profile of riveting to a pre-set profile to determine whether the riveting was performed properly.

A joining method is a method of joining a plate set composed by a plurality of stacked plate members including a first plate member and a second plate member by using a tapping screw. When the tapping screw is advanced into the plate set while the tapping screw is rotated in a state of applying a pressure onto the plate set so as to form through-holes in the first plate member and the second plate member, a first pressure applied onto the tapping screw is reduced down to a second pressure at the time when the tapping screw penetrates the first plate member.

A joining method is a method of joining a plate set composed by a plurality of stacked plate members including a first plate member and a second plate member by using a tapping screw. When the tapping screw is advanced into the plate set while the tapping screw is rotated in a state of applying a pressure onto the plate set so as to form through-holes in the first plate member and the second plate member, a first pressure applied onto the tapping screw is reduced down to a second pressure at the time when the tapping screw penetrates the first plate member.

A joining method is a method of joining a plate set composed by a plurality of stacked plate members including a first plate member and a second plate member by using a tapping screw. When the tapping screw is advanced into the plate set while the tapping screw is rotated in a state of applying a pressure onto the plate set so as to form through-holes in the first plate member and the second plate member, a first pressure applied onto the tapping screw is reduced down to a second pressure at the time when the tapping screw penetrates the first plate member.

A riveting system, for use in mechanically linking adjacent workpieces, including a rivet having a height greater than a sum of thicknesses, measured along a line of riveting, of the workpieces being linked, so that the rivet can pass fully through the workpieces. The system also includes a riveting die, which may be a separate product. The die includes a protrusion extending from a peak toward a transition point; and a trough having a trough surface. The trough surface includes a trough inner wall, extending from the transition point to a trough bottom, and a trough outer wall, extending from the trough bottom to a trough outer edge. The technology also includes computerized systems for comparing a load-displacement profile of riveting to a pre-set profile to determine whether the riveting was performed properly.

In a joining method for joining a first plate material and a second plate material by screwing a self-tapping screw from one direction in a state where the first plate material and the second plate material are put on top of each other, a recessed portion is formed in at least one of the first plate material and the second plate material, and in a state where the first plate material and the second plate material are put on top of each other such that the recessed portion is opened in a contacting face between the first plate material and the second plate material, the self-tapping screw is screwed from the one direction. When the self-tapping screw penetrates through the first plate material due to the screwing of the self-tapping screw, an excess part generated from the first plate material flows into the recessed portion.

A riveting system, for use in mechanically linking adjacent workpieces, including a rivet having a height greater than a sum of thicknesses, measured along a line of riveting, of the workpieces being linked, so that the rivet can pass fully through the workpieces. The system also includes a riveting die, which may be a separate product. The die includes a protrusion extending from a peak toward a transition point; and a trough having a trough surface. The trough surface includes a trough inner wall, extending from the transition point to a trough bottom, and a trough outer wall, extending from the trough bottom to a trough outer edge. The technology also includes computerized systems for comparing a load-displacement profile of riveting to a pre-set profile to determine whether the riveting was performed properly.

In a joining method for joining a first plate material and a second plate material b screwing a self-tapping screw from one direction in a state where the first plate material and the second plate material are put on top of each other, a recessed portion is formed in at least one of the first plate material and the second plate material, and in a state where the first plate material and the second plate material are put on top of each other such that the recessed portion is opened in a contacting face between the first plate material and the second plate material, the self-tapping screw is screwed from the one direction. When the self -tapping screw penetrates through the first plate material due to the screwing of the self-tapping screw, an excess part generated from the first plate material flows into the recessed portion.

A joining method is a method of joining a plate set composed by a plurality of stacked plate members including a first plate member and a second plate member by using a tapping screw. When the tapping screw is advanced into the plate set while the tapping screw is rotated in a state of applying a pressure onto the plate set so as to form through-holes in the first plate member and the second plate member, a first pressure applied onto the tapping screw is reduced down to a second pressure at the time when the tapping screw penetrates the first plate member.

An assembly unit is produced according to the following method steps: an assembly part is provided which does not yet have a through bore. A disc-shaped welding element blank with a first end side, a second end side and a peripheral surface is stamped out of a sheet metal blank by a punch and a hole die so that the peripheral surface has a cylindrical longitudinal portion extending away from the first end side, and an adjoining cone portion which tapers towards the second end side and forms with this a cutting edge. The welding element blank is stamped with the cutting edge at the front into the assembly part to thereby form the through bore.