A fluid control valve includes a housing defining a fluid inlet and a fluid outlet. A valve seat is coupled to the housing and is positioned between the inlet and the outlet. The valve seat includes an end surface, seating surface extending from the end surface toward the seat axis, and a groove surface extends from the seating surface and defines a groove extending around the seat axis. The valve seat further includes an inner surface defining a central bore extending along the seat axis. A spindle is disposed within the housing and is reciprocally moveable between closed and open positions within the central bore of the valve seat. The spindle defines a longitudinal axis and includes an outer surface and a plurality of flow passages formed in the outer surface to prescribed lengths and extending in generally parallel relation to the axis of the spindle.

A fluid control valve includes a housing defining a fluid inlet and a fluid outlet. A valve seat is coupled to the housing and is positioned between the inlet and the outlet. The valve seat includes an end surface, seating surface extending from the end surface toward the seat axis, and a groove surface extends from the seating surface and defines a groove extending around the seat axis. The valve seat further includes an inner surface defining a central bore extending along the seat axis. A spindle is disposed within the housing and is reciprocally moveable between closed and open positions within the central bore of the valve seat. The spindle defines a longitudinal axis and includes an outer surface and a plurality of flow passages formed in the outer surface to prescribed lengths and extending in generally parallel relation to the axis of the spindle.

In a steam valve of an embodiment, a valve element of a comprises: a first valve element part positioned in the closing direction, and including a first valve element part outer peripheral surface configured to surround the valve rod; and a second valve element part positioned in the opening direction, and including a second valve element part outer peripheral surface configured to surround the valve rod. The first valve element part outer peripheral surface is a curved surface formed to have a diameter increased toward the opening direction. A diameter of boundary position between the first valve element part outer peripheral surface and the second valve element part outer peripheral surface is the same as a seat diameter of valve seat at which the valve element is brought into contact with the valve seat when the steam valve is set to a fully-closed state.

In a steam valve of an embodiment, a valve element of a comprises: a first valve element part positioned in the closing direction, and including a first valve element part outer peripheral surface configured to surround the valve rod; and a second valve element part positioned in the opening direction, and including a second valve element part outer peripheral surface configured to surround the valve rod. The first valve element part outer peripheral surface is a curved surface formed to have a diameter increased toward the opening direction. A diameter of boundary position between the first valve element part outer peripheral surface and the second valve element part outer peripheral surface is the same as a seat diameter of valve seat at which the valve element is brought into contact with the valve seat when the steam valve is set to a fully-closed state.

Provided is a linear solenoid valve having at least one notch that opens on an end surface of the land of the spool on the drain chamber side and is formed on an outer peripheral surface of the land. In response to movement of the spool, a state is formed in which the end surface of the land on the drain chamber side is located inside the communication chamber and the output chamber and the drain chamber communicate with each other via the notch and the communication chamber, and a state is formed in which the end surface of the land on the drain chamber side is located inside the output chamber and the output chamber and the drain chamber communicate with each other via the communication chamber.

Provided is a linear solenoid valve having at least one notch that opens on an end surface of the land of the spool on the drain chamber side and is formed on an outer peripheral surface of the land. In response to movement of the spool, a state is formed in which the end surface of the land on the drain chamber side is located inside the communication chamber and the output chamber and the drain chamber communicate with each other via the notch and the communication chamber, and a state is formed in which the end surface of the land on the drain chamber side is located inside the output chamber and the output chamber and the drain chamber communicate with each other via the communication chamber.

An object of the present invention is to provide a rotary displacement compressor capable of determining whether a check valve has failed, and preventing the life of a compressor body from being reduced when a compression operation stops. In order to achieve the object, a rotary displacement compressor includes a compressor body that compresses a medium by reducing a volume of the medium using rotation; a discharge pipe through which a compressed medium, which is discharged through a discharge port of the compressor body, flows; a check valve that shuts off the compressed medium flowing backward to the compressor body; and a backflow control valve that allows a predetermined rate of the compressed medium to flow backward. The check valve and the backflow control valve are disposed in series via the discharge pipe.

An anti-cavitation valve assembly includes a seat positioned within a fluid pathway between a fluid inlet and outlet of a valve. Spaced apart elongated seat apertures are formed in a circumferential wall of the seat that have a varying opening width along a length thereof to direct fluid flow into an inner seat chamber of the seat. A disc guide is slidably movable relative to the seat and has a wall having spaced apart disc guide apertures formed therein. A tortuous fluid flow pathway is formed as fluid enters through the seat apertures, into the inner seat chamber, and exits through the disc guide apertures to minimize fluid cavitation.

An anti-cavitation valve assembly includes a seat positioned within a fluid pathway between a fluid inlet and outlet of a valve. Spaced apart elongated seat apertures are formed in a circumferential wall of the seat that have a varying opening width along a length thereof to direct fluid flow into an inner seat chamber of the seat. A disc guide is slidably movable relative to the seat and has a wall having spaced apart disc guide apertures formed therein. A tortuous fluid flow pathway is formed as fluid enters through the seat apertures, into the inner seat chamber, and exits through the disc guide apertures to minimize fluid cavitation.

Fluid flow control devices comprise a cylindrical body extending along a longitudinal axis and having a sidewall. The cylindrical body has a first channel extending longitudinally along the sidewall and a second channel extending longitudinally along the sidewall. At least a portion of one of the at least one first channel and the at least one second channel extends longitudinally at an oblique angle with respect to the longitudinal axis to form a pattern of channels for improving the flow characteristics of a fluid through the channels.