An automatic plate valve having a valve seat, a valve guard, a longitudinal axis (L) and a valve element arranged between the valve seat and the valve guard and movable along the longitudinal axis (L). The valve seat includes an end face having with valve seat openings oriented towards the valve guard, and a plurality of passages, which have a fluid-conducting connection to the valve seat openings. The valve element includes sealing element interacting with the valve seat openings. Wherein some of the passages have a different distance to the longitudinal axis in a radial direction (R). The end face of the valve seat including a plurality of grooved recesses, forming valve seat openings, with passages open into the same recess, the passages forming a fluid-conducting connection to the valve seat opening. Some of these passages connected to the valve seat opening have different distances to the longitudinal axis.

A disc pump valve for controlling the flow of fluid through a disc pump includes a first plate having first plate apertures and a second plate having second plate apertures both extending generally perpendicular through the first plate and the second plate, respectively. The second plate apertures are substantially offset from the first plate apertures. The disc pump valve also includes a sidewall disposed between the first plate and second plate. A valve flap is disposed and moveable between the first plate and second plate. The valve flap includes flap apertures substantially offset from the first plate apertures and substantially aligned with the second plate apertures, and low-mass areas. The low-mass areas are offset from the first plate apertures and second plate apertures. The valve flap moves between the first plate and second plate in response to a change in direction of differential pressure of the fluid outside the valve.

Disclosed are check valve assemblies operable to inject treatment fluids during stimulation operations. One check valve assembly includes a valve body defining an inlet, one or more discharge ports, and a cylindrical passageway that fluidly communicates the inlet with the one or more discharge ports, the valve body further providing a cylindrical section in which the one or more discharge ports are defined, a valve cap disposed about an exterior of the cylindrical section and defining an opening that fluidly communicates with the cylindrical passageway, and a spherical piston disposed within the passageway and movable between a closed configuration, where the spherical piston prevents fluid communication between the inlet and the one or more discharge ports, and an open configuration, where fluid communication is allowed between the inlet and the one or more discharge ports.

The present invention relates to a valve device characterized in that it comprises a valve component and a membrane component. The valve component comprises a bottom cover with one or more first apertures; a top cover with one or more second apertures, wherein the bottom cover and the top cover enclosing a venting chamber; a plate accommodated inside the venting chamber and being pressed by one or more projections attaching to the top cover against the one or more second apertures on the bottom cover; and wherein silicon oil is provided between the bottom cover and the plate; and wherein the plate has a diameter between 5 mm and 20 mm. The membrane component comprises a membrane made from hydrophobic material.

An automatic plate valve having a valve seat, a valve guard, a longitudinal axis (L) and a valve element arranged between the valve seat and the valve guard and movable along the longitudinal axis (L) The valve seat includes an end face having with valve seat openings oriented towards the valve guard, and a plurality of passages, which have a fluid-conducting connection to the valve seat openings. The valve element includes sealing element interacting with the valve seat openings. Wherein some of the passages have a different distance to the longitudinal axis in a radial direction (R). The end face of the valve seat including a plurality of grooved recesses, forming valve seat openings, with passages open into the same recess, the passages forming a fluid-conducting connection to the valve seat opening. Some of these passages connected to the valve seat opening have different distances to the longitudinal axis.

A valve includes a first plate, a side wall plate, a second plate, and a third plate. The first plate has a plurality of first vent holes. The second plate constitutes a valve chamber along with the first plate and the side wall plate. The second plate includes a second principal surface opposing a first principal surface of the first plate. The second plate has a plurality of second vent holes. The third plate has a plurality of third vent holes. The plurality of third vent holes overlaps with the plurality of first vent holes without overlapping with the plurality of second vent holes in a plan view in a direction in which the first plate and the second plate oppose each other. Both principal surfaces of the third plate oppose the first principal surface and the second principal surface. The third plate is disposed in the valve chamber.

A valve includes a first plate, a side wall plate, a second plate, and a third plate. The first plate has a plurality of first vent holes. The second plate constitutes a valve chamber along with the first plate and the side wall plate. The second plate includes a second principal surface opposing a first principal surface of the first plate. The second plate has a plurality of second vent holes. The third plate has a plurality of third vent holes. The plurality of third vent holes overlaps with the plurality of first vent holes without overlapping with the plurality of second vent holes in a plan view in a direction in which the first plate and the second plate oppose each other. Both principal surfaces of the third plate oppose the first principal surface and the second principal surface. The third plate is disposed in the valve chamber.