METHOD AND ASSEMBLY FOR CONNECTING A PIPE TO A COUPLING ELEMENT

摘要

The invention can be used for welding a pipe to a coupling element, in particular a thin-walled pipe with a wall thickness within the range of 1.5-3.0 mm and an outside diameter of 16 or 20 mm, manufactured from polyethylene of increased thermal stability or low-pressure polyethylene or polypropylene. A sleeve (5) is mounted into the weldable end of the pipe (1) until a bead (6) rests against the end plane of the pipe. A section of the outside surface of the pipe (1) and a section of the inside surface of the coupling element (2) are heated simultaneously using welding attachments, which are fixed on a heater, until the surfaces of the above-mentioned sections melt. The pipe (1) and the coupling element (2) are removed from the welding attachments and the end of the pipe (1) is inserted into the cavity of the coupling element (2) with the melted surfaces being joined. A final curing of the connection takes place until the melted thermoplastics material hardens, forming a diffusion welding zone (8). The assembly for connecting the pipe (1) to the coupling element (2) by diffusion welding comprises a sleeve (5) in the form of a length of thin-walled pipe with an outwardly bent bead (6) on one of the end planes, the height of which bead does not exceed the thickness of the pipe (1). The length of the sleeve (5) is greater than the length of the welding zone (8). A high degree of uniformity and homogeneity of the diffusion welding zone is achieved.