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.

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 nozzle check valve comprises a valve body (10) and a nozzle (20) centrally arranged within the upstream end of valve body (10), a fluid channel (90) is defined by the outer face of the nozzle (20) and the inner face of the valve body (10). A guide bush (60) is mounted on a nozzle axial extension (26) and an annular disc (30) comprising a disc sealing ring (31) connected to a central barrel (32,33) by a plurality of webs (34) is mounted on the guide bush (60) for axial movement of the annular disc (30) relative to the valve body to open and close the fluid channel (90). A spacer (80) is arranged on the nozzle axial extension (26) downstream of the guide bush (60) and a diffuser (40) is arranged on the downstream side of the spacer (80). A spring (50) between the annular disc (30) and the diffuser (40) urges the disc towards the valve closed position. The stroke of the valve, the maximum movement of the annular disc (30) from the valve closed position to the valve open position where the annular disc (30) is in contact with the upstream face of the diffuser (40), is determined by the axial length of the spacer (80). The centre of mass of the annular disc (30) is located along the central axis of the disc (30) at an axial position where the barrel (32) is in sliding contact with the guide bush (60).

A nozzle check valve comprises a valve body (10) and a nozzle (20) centrally arranged within the upstream end of valve body (10), a fluid channel (90) is defined by the outer face of the nozzle (20) and the inner face of the valve body (10). A guide bush (60) is mounted on a nozzle axial extension (26) and an annular disc (30) comprising a disc sealing ring (31) connected to a central barrel (32,33) by a plurality of webs (34) is mounted on the guide bush (60) for axial movement of the annular disc (30) relative to the valve body to open and close the fluid channel (90). A spacer (80) is arranged on the nozzle axial extension (26) downstream of the guide bush (60) and a diffuser (40) is arranged on the downstream side of the spacer (80). A spring (50) between the annular disc (30) and the diffuser (40) urges the disc towards the valve closed position. The stroke of the valve, the maximum movement of the annular disc (30) from the valve closed position to the valve open position where the annular disc (30) is in contact with the upstream face of the diffuser (40), is determined by the axial length of the spacer (80). The centre of mass of the annular disc (30) is located along the central axis of the disc (30) at an axial position where the barrel (32) is in sliding contact with the guide bush (60).

An apparatus for controlling fluid flow from a first location to a second location includes a body, a valve, a shear seal, and a biasing member. The body has a fluid conduit and a chamber. The conduit has an inlet that communicates with the first location and an outlet that communicates with the second location. The valve is disposed in the chamber and has a seal separating the chamber into a pressure section and a flow section. The pressure section communicates with the outlet via an outlet fluid branch. The shear seal has a movable sealing element disposed on the valve and a stationary sealing element disposed in the body. The biasing member urges the valve to a closed position wherein the stationary sealing element sealingly engages the movable sealing element. Pressure communicated by the outlet fluid branch also urges the valve to the closed position.