Abstract: In order to provide a piston device that is of simple construction and provides optimised sealing, it is proposed that the piston device should include the following: a housing that includes a piston receptacle; a piston that is arranged to be linearly displaceable in the piston receptacle; a main gasket element that separates a first medium space from a second medium space, and a supplementary gasket element, different from the main gasket element, for sealing in a region between the piston and the piston receptacle.

Abstract: In order to provide a sealing element which ensures a reliable seal and which can be produced easily and economically, it is proposed that a main body of the sealing element is preferably formed from a partially fluorinated or fully fluorinated thermoplastic material and has obtained at least part of its final outer shape or only part of its final outer shape in particular in a high-pressure process and/or in a high-temperature process.

Abstract: In the case of a heat exchanger element for equipping heat exchangers of flue gas cleaning systems of power stations, the heat exchanger element can be formed by a block shaped honeycomb body having four outer faces and two substantially parallel end faces and a sealing edge. The honeycomb body can be manufactured from a plastics material including a plurality of mutually parallel flow channels which are separated from each other by channel walls. The flow channels extend from the one to the other end face, and the sealing edge can be arranged in the region of one of the end faces and substantially parallel to this end face and extends away from the honeycomb body at the periphery of the honeycomb body.