A check valve includes a housing defining an inlet, an outlet, a passage between the inlet and outlet, and a sealing surface along the passage. A piston member is disposed about a longitudinal axis and has a sealing face disposed perpendicular to the longitudinal axis and a circular groove defined therein extending inward from the sealing face. An O-ring is disposed in the groove. A biasing member exerts a biasing force on the piston and thus forces the O-ring into sealing engagement with the sealing surface of the housing. The piston member is moveable from a first position in which the O-ring is sealingly engaged with the sealing surface of the housing and thus the outlet is sealed from the inlet, and a second position in which the O-ring is spaced from the sealing surface of the housing and thus the outlet is not sealed from the inlet.

A device and method to improve accuracy of a water meter where a fluid is introduced into a valve assembly having an external casing. The fluid contacts a toggle stopper having a shaft, plate, and guides. A calibrated spring positioned around the shaft in contact with the plate assesses if the desired fluid meets a predetermined pressure. If yes, the calibrated spring compresses thereby toggling the plate within the chamber to allow desired fluid to enter the chamber. If no, the calibrated spring remains in an expanded state to seal the valve assembly. Upon such seal, there is an equalizing of both the desired and undesired fluids to the same pressure by decreasing the volume of the undesired fluid, causing the calibrated spring to compress and reopen.

A non-return valve (19) for a water supply system (1) or a pump (4) is integrated in a flow channel (14) of the water supply system (1). The non-return valve (19) includes a sealing body (21) which is mounted within the channel (14), blocks the channel (14) in a first position forming the closure position and releases the channel (14) in a second position forming the opened position. The sealing body (21) is movably arranged on a holder (31) which includes a closure body (15), with which the holder (31) is releasably fastened in a housing opening.

A one-way valve is provided. The one-way valve may be, for example, a check valve, a relief valve, or the like, which may be in the form of a poppet valve. The valve provides a housing with a through hole. The through hole has an upstream portion and a downstream portion. The upstream portion has a reduced diameter compared to the downstream portion. The housing contains a valve seat, which typically has a taper. A poppet, or valve member, moves within the through hole from a valve closed position and a valve open position. The poppet has a high pressure facing side and a low pressure facing side opposite the high pressure facing side. The low pressure facing side of the poppet engages an elastic member of a compression member that biases the poppet in the valve closed position. The high pressure facing side of the poppet engages a resilient metal seal in the form of an annular disc. The annular disc has a generally wavy or undulating shape. The outer ends of the resilient metal seal have a curve or arc shape and provide a seat interface that releasably engages the valve seat.

The present invention discloses a device for flow control of fluid in pipelines to various utility fluid outlets like water taps and the like by blocking fluid flow from pipeline to said utility fluid outlet when the flow exceeds a predetermined flow rate. In other word, the present invention discloses an automatic fluid flow controlling device for restricting and/or stopping flow of the fluid medium miming through the guiding means or the tubing system when fluid flow exceed a certain flow rate as well as stopping flow of the running fluid flow when fluid level in the vessel wherein the running fluid is being delivered reaches a certain height.

A system includes a flow control assembly having a first portion configured to be positioned within and coupled to a first passageway formed in a wellhead component and a second portion configured to be coupled to a second passageway formed in a body that is configured to be coupled to the wellhead component. An actuator of the second portion is configured to drive a valve member of the first portion into an open position to enable fluid flow across the flow control assembly.

A check valve having a valve that is movable by incoming water in the flow direction, from a closed position, where it bears against a first valve seat, against a restoring force into an open position, where it is raised from the first valve seat, and having a pressure relief valve with a closing member that is movable by pressure of the water flowing back against the flow direction, from a closed position, in which it bears against a second valve seat, against a restoring force into an open position where it is raised from the second valve seat. The restoring force acting on the closing member is greater than the restoring force acting on the valve body. The closing member has a closing member core made of a first material, and at least in the partial region thereof that abuts the second valve seat in the closed position, has a film or a layer made of a second relatively softer and/or elastic material.

A pressure actuated switching valve includes a first valve chamber including a first chamber portion. The first chamber portion has a first inner diameter, a second chamber portion having a second inner diameter that is greater than the first inner diameter, a third chamber portion having a third inner diameter that is greater than the first inner diameter, a fourth chamber portion having a fourth inner diameter that is greater than first inner diameter, and a valve member. The valve member includes a first section having a first outer diameter that is greater than the first inner diameter. A second section of the valve member has a second outer diameter that is closely matched to the third inner diameter. A third section of the valve member is arranged has a third outer diameter that is greater than the first outer diameter.

The present invention relates to a stop valve for installation in a pipeline, in particular in a pipeline of a nuclear facility, such as a nuclear power plant, or in a conventional chemical reactor and in a conventional power plant, to stop a fluid flow through the pipeline in the event of an operational failure. The valve comprises a valve housing including a flow channel passing through the valve housing, and a closure member arranged at least partially in the flow channel and reversibly transferable between an open position and a closed position such as to open or close the flow channel through the valve housing. The valve further comprises a non-electrically driven actuator mechanism operatively coupled to the closure member for transferring the closure member at least from the open position in the closed position. The actuator mechanism is configured to be activated by a fluid flow through the flow channel reaching or exceeding a switching temperature and/or switching flow rate during operation. In addition, the valve comprises at least one position indicator to indicate whether the closure member is in the open position or in the closed position. The position indicator comprises at least one indicator member movably arranged in or at the valve housing between a first position and a second position, wherein the indicator member is magnetically coupled to the closure member such that the indicator member is magnetically transferred into the first position when the closure member is transferred into the open position, and into the second position when the closure member is transferred into the closed position.

An oil pressure supply device supplies, to an oil chamber, an oil pressure generated by suctioning oil from an oil source with an oil pump. The oil pressure supply device includes a first oil passage connected to a suction side of the oil pump; a first check valve provided in the first oil passage and configured to close the first oil passage and prevent oil from moving to the oil source side when the oil pump is stopped; a second oil passage connected to a discharge side of the oil pump; and a second check valve provided in the second oil passage and configured to close the second oil passage and prevent oil from moving to the oil pump side when the oil pump is stopped. When the oil pump is stopped, the second check valve closes the second oil passage earlier than the first check valve closes the first oil passage.