Abstract: A method and a device for connecting a plastic line part in a plastic socket. A head end (9) of the line part (6) is heated contactlessly all the way round until the end curls over to a diameter that is greater than the inside diameter of the socket (5). The line part is then pushed into the socket without using a mandrel or insert, so that the head end (9) forms a liquid-tight fused connection of high tensile strength with molten wall material of the socket (5).

Abstract: An assembly of a tapping keg with neck and a connecting device for placement on said neck, wherein in the neck at least one valve is provided and wherein the connecting device is provided with prssure means for pressing the at least one valve open, wherein the neck is provided with an outwardly reaching flange with a top surface and a bottom surface, wherein the bottom surface is inclined with respect to the top surface and has at least a substantially planar central part, wherein the connecting device has a substantially horse shoe-shaped connecting element, provided with a slot by way of which the connecting element is slidable over the flange, wherein the side of the slot facing the bottom surface during use comprises a surface which is inclined at an angle which is at least virtually equal to the angle of inclination of the bottom surface and, in coupled condition, abuts at least against the planar central part of the bottom surface.