Abstract: A valve device, in particular a lifting valve device, includes a housing, a valve seat, and a movable closing body that can be brought into an open position in an opening movement and into a closed position in a closing movement. In the closed position, the closing body and the valve seat are in sealing contact. The valve device also includes a piston to which a pressure medium can be applied and that is received in a cylinder. To improve hygienic properties, it is proposed that the cylinder is part of the closing body.

Abstract: A valve device, in particular a lifting valve device, includes a housing, a valve seat, and a movable closing body that can be brought into an open position in an opening movement and into a closed position in a closing movement. In the closed position, the closing body and the valve seat are in sealing contact. The valve device also includes a piston to which a pressure medium can be applied and that is received in a cylinder. To improve hygienic properties, it is proposed that the cylinder is part of the closing body.

Abstract: A self-priming pump assembly comprises a series connection of a liquid ring pump functioning as a rotating displacement pump and a normally-priming centrifugal pump. The self-priming pump assembly improves the fluid mechanics conditions for the flow of fluids toward and into a return line through the inclusion of a first connection opening in the meridian plane of the centrifugal pump that possesses a bulge enclosing a sector of the longitudinal axis of the first connection opening, where the bulge is one-sided and oriented toward a rotary axis of the pump assembly, and the bulge continuously expands, directly or indirectly, the first connection opening toward the impeller plane. At its end section facing the impeller plane, a transitional surface of the bulge continuously transitions into the lateral boundary surface, or an inner peripheral wall of the ring channel adjoining the lateral boundary surface.

Abstract: A self-priming pump is described that has a housing, an inlet, and an outlet. A first impeller has a first pump section that is arranged in a first chamber, and a second impeller has a second pump section that is arranged in a second chamber. A shaft section is provided between the pump sections, and has a shaft end and penetrates an opening in a housing wall. To improve the net positive section head of the pump, the shaft section between a constriction and the shaft end is formed to taper from the shaft end toward the constriction, and the first impeller and shaft section between the constriction and first pump section has a smooth contour.

Abstract: A self-priming pump assembly comprises a series connection of a liquid ring pump functioning as a rotating displacement pump and a normally-priming centrifugal pump. The self-priming pump assembly improves the fluid mechanics conditions for the flow of fluids toward and into a return line through the inclusion of a first connection opening in the meridian plane of the centrifugal pump that possesses a bulge enclosing a sector of the longitudinal axis of the first connection opening, where the bulge is one-sided and oriented toward a rotary axis of the pump assembly, and the bulge continuously expands, directly or indirectly, the first connection opening toward the impeller plane. At its end section facing the impeller plane, a transitional surface of the bulge continuously transitions into the lateral boundary surface, or an inner peripheral wall of the ring channel adjoining the lateral boundary surface.

Abstract: A self-priming pump is described that has a housing, an inlet, and an outlet. A first impeller has a first pump section that is arranged in a first chamber, and a second impeller has a second pump section that is arranged in a second chamber. A shaft section is provided between the pump sections, and has a shaft end and penetrates an opening in a housing wall. To improve the net positive section head of the pump, the shaft section between a constriction and the shaft end is formed to taper from the shaft end toward the constriction, and the first impeller and shaft section between the constriction and first pump section has a smooth contour.