Abstract: A method and a device for connecting parts of an exhaust gas system which comprises at least one metal tube formed from a bellows and optionally further parts disposed coaxially within and/or outside of the bellows and at least one further system part to be connected to the metal tube, are characterized in that one end of a short connecting tube is inserted positively in an end of the metal tube and the other end is inserted positively in the system part to be connected to the metal tube, and the system part is moved to the end of the metal tube facing the system part, thereby leaving a gap, and the system part, the connecting tube and the metal tube being connected from the outside in one working step.

Abstract: Connecting ends on a tube piece comprising several metal layers, in particular a wound metal tube piece, are produced by fixing the overlapping metal layers of a tube of larger length or of an endless tube in the region of the point of separation through welding and subsequently cutting off the tube piece from the longer tube or the endless tube. For simple and inexpensive fixing of the metal layers in the region of the point of separation, the invention proposes effecting a welding seam which extends through at least part of the periphery of the tube or about its entire periphery, using seam welding. The tube piece can subsequently be separated along the welding seam obtained in this manner, e.g. along its central line, thereby ensuring permanent and reliable fixing of the metal layers in the region of the connecting end. The invention also concerns a tube piece having a connecting end produced in this manner.

Abstract: The invention concerns a flexible pipe element, in particular for exhaust pipes of combustion engines of motor vehicles, with a helically threaded or ring-corrugated bellows, at least one strip wound hose which is coaxially adjacent to the bellows and which is helically wound or comprises several annular segments, at least one spacer which is disposed locally between the bellows and the strip wound hose and a knitted tube disposed on the outside, wherein the pipe element has an overall maximum rigidity of 5 N/mm.

Abstract: A method and a device for connecting parts of an exhaust gas system which comprises at least one metal tube formed from a bellows and optionally further parts disposed coaxially within and/or outside of the bellows and at least one further system part to be connected to the metal tube, are characterized in that one end of a short connecting tube is inserted positively in an end of the metal tube and the other end is inserted positively in the system part to be connected to the metal tube, and the system part is moved to the end of the metal tube facing the system part, thereby leaving a gap, and the system part, the connecting tube and the metal tube being connected from the outside in one working step.

Abstract: A device for assembly of a flexible conduit element consisting essentially of a flexible ring-corrugated or helical-shaped bellows body which is displaced over an inner arbor in order to introduce a jacket into the corrugations of the bellows body, has an the inner arbor comprising actuating elements for engagement into the corrugations of the bellows body at an inner side thereof. The inner arbor has an axial length which can be adjusted.

Abstract: A bending metal pipe element for bending pipe sections, in particular for return pipes in combustion engines of automobiles, comprising undulations which are disposed one behind the other in the longitudinal direction of the pipe element, is characterized in that the undulations have different outer diameters and undulations having the same outer diameter are disposed in alternating pairs.