A tool for joining a coupling element, such as a flange to a pipe, wherein the coupling element surrounds the pipe and has grooves facing the pipe to receive a corresponding plurality of beads provided on the pipe. The tool has a plurality of axially separated, radially movable segments. Each segment has a plurality of circle sector formed ridges. The plurality of segments thereby provides circumferentially extending ridges that are capable of deforming a pipe wall by a first pressing action on the inside wall of the pipe to create on the outside of the pipe circumferential beads in the pipe wall and to cause these beads to extend into corresponding grooves in the coupling element. The segments also have circumferentially extending portions located adjacent and between the ridges. The extending portions in a second, subsequent passing action cause post-pressing of buckled-in areas that occur naturally in the pipe wall between and adjacent to the beads during the first pressing action, so that an outward tension is obtained in the pipe at the location of the coupling element.