Abstract: A fluid-actuated diaphragm drive and a valve arrangement which is equipped therewith, wherein the diaphragm drive has a drive housing with two drive housing parts which are attached to one another axially. An insert body which preferably consists of plastic material and delimits at least one length section of an operating chamber which can be loaded with a fluid is inserted into each of the drive housing parts, wherein a drive diaphragm which is movement-coupled to an output member is clamped in between the two insert bodies. A seal structure which is active between at least one of the insert bodies and the drive housing is capable of preventing an axial flow around the two insert bodies in the region which lies radially between them and the drive housing.

Abstract: An operating unit for a fluid-operated diaphragm actuator, the unit consisting of a drive diaphragm, two retaining elements flanking the drive diaphragm on opposite sides and an output rod extending through these components. The drive diaphragm is mounted on the output rod by being clamped between the two retaining elements with a predetermined clamping force, wherein each of the two retaining elements is fixed on the output rod by means of a welded connection. A method that is particularly suitable for producing such an operating unit and to a fluid-operated diaphragm actuator equipped with such an operating unit.

Abstract: A pneumatic actuator for controlling a valve, having a working piston which is movably accommodated in a cylinder housing along a movement axis and delimits a working space of variable size with the cylinder housing and which is connected to a piston rod which extends along the movement axis, the cylinder housing including a first outer body with a sleeve-shaped first piston rod guide and a second outer body with a sleeve-shaped second piston rod guide, wherein the two piston rod guides are arranged spaced apart from one another along the axis of movement, the working space being bounded by the first outer body and by the second outer body, and the piston rod passing through the end of the cylinder housing, wherein the piston rod is provided with a sealing in order to form a sealing connection with the associated piston rod guide.

Abstract: An operating unit for a fluid-operated diaphragm actuator, the unit consisting of a drive diaphragm, two retaining elements flanking the drive diaphragm on opposite sides and an output rod extending through these components. The drive diaphragm is mounted on the output rod by being clamped between the two retaining elements with a predetermined clamping force, wherein each of the two retaining elements is fixed on the output rod by means of a welded connection. A method that is particularly suitable for producing such an operating unit and to a fluid-operated diaphragm actuator equipped with such an operating unit.

Abstract: A fluid-actuated diaphragm drive and a valve arrangement which is equipped therewith, wherein the diaphragm drive has a drive housing with two drive housing parts which are attached to one another axially. An insert body which preferably consists of plastic material and delimits at least one length section of an operating chamber which can be loaded with a fluid is inserted into each of the drive housing parts, wherein a drive diaphragm which is movement-coupled to an output member is clamped in between the two insert bodies. A seal structure which is active between at least one of the insert bodies and the drive housing is capable of preventing an axial flow around the two insert bodies in the region which lies radially between them and the drive housing.