Abstract: The apparatus makes it possible to change a desired sample volume—even during operation—in a simple manner without mechanical intervention, with any accumulation solids of a sample contained in a sample collecting vessel being avoided, so that a sample representative of the medium is obtained. The apparatus comprises a control unit which controls a pneumatic control gear and switches a pump by means of which the medium is drawn into a sample collecting vessel via a hose or tube used as a suction line. A detection unit incorporated in the suction line signals the presence of the medium to the control unit, which then controls the time period for taking the desired volume of the sample. The sample volume obtained is drained off into a sample container via a drain device.

Abstract: A metal plug with a plug screw in a casing for attachment of articles to penetrable material. The plug screw of the plug serves a dual function; fixing the plug in the material and also permitting the variation of the distance of the articles relative to the penetrable material. The plug screw has a plug-screw head at a back end, a constricted diameter portion designated as an intended breaking point, and a front end coupled to a spreading cone, a spreading head, and a fixing head. The plug is anchored in the penetrable material by means of the spreading head in the following way. First, by turning the plug screw by means of the plug-screw head, the spreading head with spreading jaws is pulled onto the spreading cone and the spreading jaws of the spreading head engage in the penetrable material.