VERFAHREN ZUM HERSTELLEN VON ROHRVERBINDUNGEN UND WERKZEUG ZUM AUSFÜHREN DIESES VERFAHRENS

摘要

A method for establishing a connection between one end (8) of a pipe (1) made of a plastic material having memory properties and a flanged connector sleeve (3) of a pipe-connecting piece (2; 11), comprising expanding the pipe-end (8) to an inner diameter which exceeds the outer diameter of the flange, and inserting the flanged connector sleeve (3) into the expanded pipe-end. There is used to this end an expanding tool (15) which comprises a number of movable expander jaws (22) which have an essentially circular-arcuate shape in cross section and which include outer jaw surfaces (27) that are delimited by mutually opposing jaw edges (28) and present recesses, e.g. grooves (32, 33), in the region of the jaw edges (28). As the pipe is expanded, there are formed on the inner surface of the pipe-end (8) inwardly directed beads (30; 31) which interrupt the contact zones between the inner surface of the pipe-end and the outer jaw surfaces (27) in the region of the edges (28) of the expanded jaws (22). The connector sleeve (3) of the connecting piece (2; 11) has provided forwardly of the flange (6) an axially outer, tubular part (5) which has an outer diameter which is at least essentially equal to the inner diameter of the unexpanded plastic pipe (1) and which has a length which is at least equal to the inner diameter of the unexpanded plastic pipe.