Apparatus for cold joining a coupling element to a pipe

An apparatus for joining a coupling element to a pipe comprising;

• a) a coupling element connectable to a pipe separate and apart from any other pipe, the coupling element having an annular portion with an annular inner surface and a flange portion that extends radially from the annular portion,
• b) the annular portion being sized to surround an outside surface of a pipe at an end region of the pipe that includes a pipe opening,
• c) the annular inner surface being formed with an annular recess at a foremost portion of the coupling element for alignment with an open end of a pipe, the annular recess having a predetermined diameter greater than the outer diameter of a pipe at an open end to permit an open end of a pipe to flare outwardly into the annular recess,
• d) the annular inner surface also being formed with a plurality of axially spaced annular grooves to permit portions of a pipe wall to deform into the annular grooves as circumferential heads that project into the annular grooves to join the coupling element to a pipe,
• e) an expansion tool having a longitudinal axis, a first plurality of axially separated, radially movable segments, each said segment having axially spaced circular sector-formed ridges that provide the tool with a plurality of circumferentially extending ridges that respectively align with respective said annular grooves in the coupling element, to form circumferential beads in a pipe wall that project into the annular grooves, said segments further including a sector-formed projection that provides the tool with a circumferential extending projection that aligns with the annular recess at the foremost portion of the coupling element, to form a flared end of a pipe to extend radially outwardly into the annular recess,
• and wherein the axially spaced annular grooves in the coupling element have a first axial width and the corresponding circumferentially extending ridges in the expansion tool have a second axial width, the first axial width being substantially greater than the second axial width,
• and wherein the segments have circumferential curved portions parallel to the longitudinal axis of the expansion tool and located adjacent and between the circumferentially extending ridges, for a post-pressing of any buckled-in areas of a pipe that occur in a pipe wall between and adjacent the circumferential beads that are formed in a pipe wall during a first pressing action, such post-pressing of any buckled-in areas of a pipe producing a radially outward tension in a pipe at the location of the coupling element.