Method and apparatus for cold joining flanges and coupling elements to pipes

A tool for joining a coupling element, e.g. a joining flange means, to a pipe, said coupling element intended to surround the pipe and having grooves facing the pipe and intended to receive a corresponding plurality of beads provided on the pipe, characterised in

• that the tool has plurality of axially separated, radially movable segments (10), each segment having a plurality of circle sector formed ridges, said plurality of segments thereby providing circumferentially extending ridges (11) capable of deforming the pipe wall by a first pressing action on the inside wall of the pipe to create on the outside of the pipe circumferential beads (5;
• 6) in the pipe wall and cause said beads (5;
• 6) to extend into corresponding ones of said grooves (3;
• 4) in the coupling element, and
• that the segments have circumferentially extending portions (13) located adjacent and between the ridges, said portions (13) in a second, subsequent passing action to cause post-pressing of buckled-in areas that occur naturally in the pipe wall between and adjacent the beads during the first pressing action, so that an outward tension is obtained in the pipe at the location of the coupling element.