Abstract: A drive that is drivable by a pressure medium is described. The drive is used for a valve that can be used in hygienic applications. The drive includes a drive housing, in which a main piston is movable along a stroke direction by the action of the pressure medium and can be coupled to a rod, and a stop for limiting a movement of the main piston. To improve the drive, it is proposed that an additional piston is provided, which is movable by the action of the pressure medium. The stop can be carried along by the additional piston. The disclosure also describes a double-seat valve comprising such a drive and to a method for operating such a drive.

Abstract: A lifting valve includes a first and a second connection, a passage connecting the first and second connections and surrounded by a valve seat, a closing element that can be brought into sealing contact with the valve seat, and an actuator to bring about the sealing contact. The closing element includes a sealing arrangement comprising a first part, a second part releasably connected to the first part, a first groove formed in the first part, a second groove, and a clamping gap. The second groove and clamping gap are formed between the first and second parts, and a seal comprising a first leg, a second leg, and a third leg is received in the sealing arrangement. The first leg is received in the first groove, the second leg is received in the second groove, and the third leg is received in the clamping gap.

Abstract: The invention relates to an actuating device for a rotatable closure part of a valve, in particular a pneumatically or hydraulically actuatable rotary drive for a disk or throttle valve, with a housing, in which a drive piston that is sealed from a cylindrical housing casing is arranged and is suppliable on one side with a pressurizing medium, which preferably has a tubular piston skirt, with a drive shaft, which is guided on one side out of the housing and drives in a rotating manner the closure part indirectly or directly, wherein the drive piston executes either an axial shift movement against the effect of at least one return spring in the case of a one-sided supply with the pressurizing medium or a back and forth shift movement in the case of an alternating supply with a pressurizing medium, wherein the piston skirt experiences an axially oriented guidance in the housing via at least one axial groove formed in it, into which a straight-line guide cam permanently connected with the housing engages, and wh

Abstract: A method for cleaning the seat of a double seat valve, the double set valve having a deflection surface bordering the remaining area of a recess not delimiting a circumferential wall and opening out from the latter at a front and radially inside end of a second closing member facing a first closing member. The method rinses the seating when closing members are opened and generates a seat cleaning flow and urges a first cleaning flow through a deflection surface.

Abstract: A double-seat valve has a seat-cleaning function and ensures that the seat-cleaning flow is conducted into and out of the leakage hollow space with as little turbulence as possible. The valve reliably prevents a pressure-increasing direct action upon the seat regions, even in the event that the cross-sectional area of the drain bore is smaller than that of the largest pipeline that can be connected to the valve. This is achieved in that a region of extension of the deflection surface that faces away from the radially outer end of the deflection surface delimits the remaining region of the opening in its entirety and opens out from the second closing element at an end-face and radially inner end of the second closing element, facing the first closing element.

Abstract: A valve has a valve housing with a first port and a second port, and has a closing member movable along an axial direction. When in a closed position, the closing member interacts sealingly with a valve seat to block a fluid connection between the first and second ports. An fluid-impermeable diaphragm comprises a central opening through which a closing member arrangement including the closing member extends, and a clamping section that runs in a clamping gap. The diaphragm is held with sealing action between the closing member arrangement and a holding arrangement on the housing. The diaphragm has a first section and a second section adjoining the first section. The first section is held in the holding arrangement with a force fit, the second section is guided in the holding arrangement, and the first and second sections are arranged at an angle relative to one another. A form fit is generated by the first section, second section and holding arrangement.

Abstract: A double-seat valve has a seat-cleaning function and ensures that the seat-cleaning flow is conducted into and out of the leakage hollow space with as little turbulence as possible. The valve reliably prevents a pressure-increasing direct action upon the seat regions, even in the event that the cross-sectional area of the drain bore is smaller than that of the largest pipeline that can be connected to the valve. This is achieved in that a region of extension of the deflection surface that faces away from the radially outer end of the deflection surface delimits the remaining region of the opening in its entirety and opens out from the second closing element at an end-face and radially inner end of the second closing element, facing the first closing element.

Abstract: The invention relates to an actuating device for a rotatable closure part of a valve, in particular a pneumatically or hydraulically actuatable rotary drive for a disk or throttle valve, with a housing, in which a drive piston that is sealed from a cylindrical housing casing is arranged and is suppliable on one side with a pressurizing medium, which preferably has a tubular piston skirt, with a drive shaft, which is guided on one side out of the housing and drives in a rotating manner the closure part indirectly or directly, wherein the drive piston executes either an axial shift movement against the effect of at least one return spring in the case of a one-sided supply with the pressurizing medium or a back and forth shift movement in the case of an alternating supply with a pressurizing medium, wherein the piston skirt experiences an axially oriented guidance in the housing via at least one axial groove formed in it, into which a straight-line guide cam permanently connected with the housing engages, and wh

Abstract: A valve has a valve housing with a first port and a second port, and has a closing member movable along an axial direction. When in a closed position, the closing member interacts sealingly with a valve seat to block a fluid connection between the first and second ports. An fluid-impermeable diaphragm comprises a central opening through which a closing member arrangement including the closing member extends, and a clamping section that runs in a clamping gap. The diaphragm is held with sealing action between the closing member arrangement and a holding arrangement on the housing. The diaphragm has a first section and a second section adjoining the first section. The first section is held in the holding arrangement with a force fit, the second section is guided in the holding arrangement, and the first and second sections are arranged at an angle relative to one another. A form fit is generated by the first section, second section and holding arrangement.

Abstract: A method for cleaning the seat of a double seat valve and the double set valve has a deflection surface bordering the remaining area of a recess not delimiting a circumferential wall and opens out from the latter at a front and radially insise end of a second closing member facing a first closing member.

Abstract: The invention relates to a double-seat valve including closing elements (3,4) which can be transferred independently of one another by a respective partial lift gap-wide into a seat cleaning position for purposes of flushing their coaxial seat surfaces (2a, 2b), the second closing element (4) by a second partial lift (T2) which acts in the same direction as the opening motion and the first closing element (3) by a first partial lift (T1) which acts in the direction opposite the opening motion travelling into its respective seat cleaning position. The second closing element (4) in its closed position has a stop face (4f) forming a second circumferential edge (U2). A deflection surface (4d) discharges in a front face (4e) of a recess (4b) which is oriented essentially perpendicular to the longitudinal axis of the second closing element (4). The deflection surface (4d) has a contour (K) which runs without bends.

Abstract: The invention relates to a double seat valve with cleanable seats, the valve including first and second closing elements (3, 4) and a leakage cavity (5). An intermediate seal (8) seals the closing elements (3, 4) in their opening and closing movements and in the open position against each other, is arranged in the second closing element (4). The second closing element (4) abuts in its closed position at a transition area (2e, 2e*) with a stop face (4e) arranged at a front face of a cylindrical lug (4*) and that directly adjacent to a first seat (2a, 2g), a central recess (4d) is provided in a front face of a second cylindrical lug (4*).

Abstract: A double seat valve in which a second closing element (4), in its closed position, rests with a stopping surface (4f) on a face of its cylindrical projection (4*) directly upon a first seat (2a) and, together with a peripheral wall (4c, 4h), forms a second wraparound edge (U2) upon an interface (2e, 2e*). The peripheral wall (4c), at its end facing away from a first closing element (3), merges into a rotationally symmetric reversing surface (4d) that leads to a face (4e) of a recess (4b) oriented essentially perpendicular to the longitudinal axis of the second closing element (4). In meridian section, the reversing surface (4b) has a contour (K) with a bend-free curve, a direction vector in the leading point of the reversing surface (4d) points into a discharge borehole (3d, 3d*) central in the first closing element (3) without colliding with the first closing element (3) in the vicinity of its areas bordering the leakage cavity (5) and forming dynamic pressure.

Abstract: The invention relates to a double-seat valve, the seats of which can be cleaned, which is improved compared to the prior art in that discharge of the seat cleaning flow into and out of the leakage cavity as much as possible without turbulence is ensured, and pressure-increasing direct action on the seat areas is reliably avoided.

Abstract: The invention relates to a double seat valve, which is capable of cleaning the seat and which is improved compared to that of the prior art, whereby a delivery as free from turbulence as possible of the seat cleaning flow into and out of the leakage cavity is ensured, and a pressure-increasing direct action upon the seat areas is reliably prevented.

Abstract: The invention relates to a double seat valve with cleanable seats, which is improved with regard to the prior art in that a discharge possibly free of turbulence of the seat cleaning flow into and out of the leakage cavity is ensured and a direct admission of the seat areas, which would increase pressure, is safely avoided.