A gas pressure regulating device is provided which comprises an upper housing and a lower housing, a pressure regulation cavity is disposed between the upper housing and the lower housing, a diaphragm assembly is disposed in the pressure regulation cavity, a gas inlet and a valve port for communicating the gas inlet with the pressure regulation cavity are disposed at one end of the lower housing. The gas pressure regulating device provided in the present invention has a simpler structure and fewer parts and is capable of effectively lowering the risks of dangerous accidents such as product leakage resulting from part failure, thus effectively ensuring stable pressure regulation performance.

A relief valve has a valve body, a plunger assembly coupled to the valve body for selectively opening and closing the relief valve, and a support member secured to the valve body. A lockout lever is against the support member, forming a vertex. A spring rod is coupled to the lockout lever, and a spring is coupled to the spring rod, providing a bias force against the plunger assembly to normally close the relief valve. In a lockout position, the lockout lever is moved to pivot on the vertex against the support member to further compress the spring, which increases the bias force and, in turn, a cracking pressure of the relief valve.

A relief valve provides pressure relief when a fluid line exceeds a predetermined pressure. The valve includes a body which defines a cavity between inlet and outlet flowpaths. The valve includes a lever arm, which pivots around a pivot point as the valve changes between open and closed positions. A plunger assembly is disposed in the cavity and seals the cavity from the inlet and outlet flowpaths in the closed position. Fluid pressure from the inlet flow path causes the plunger assembly to contact the lever arm to urge the lever arm to rotate. The lever arm engages a spring at a further distance from the pivot point than the plunger assembly, the spring resisting pivoting of the lever arm and urging the valve to remain in the closed position unless a predetermined pressure is exceeded.

A pressure relief valve controller (PRVC) includes a housing having a spring, a spring seat connected to the spring, a piston, and a portion of which is disposed between the spring seat and the piston, wherein one or more grooves and/or protrusions are disposed on at least one of the spring seat or the piston. The diaphragm can conform to the one or more grooves of the spring seat thus preventing diaphragm rupture due to excess pressure without affecting calibrations of current PRVCs.

A fluid pressure reducing valve apparatus includes a pressure reducing valve. The valve has: a body containing a fluid-flow chamber, a liquid supply orifice into the chamber, a liquid outlet from the chamber, a regulation plate opposed to the orifice, a spring acting to urge the plate towards the orifice, and a diaphragm between the plate and the body to close the chamber between them. A controllable motor drive acts between the body and an end of the spring remote from the plate. A flow meter is positioned downstream of the outlet. A controller is arranged to receive flow data from the flow meter and to control the motor drive for withdrawal of the remote end of the spring in accordance with flow rate measured by the flow meter. For an increase in demand flow, the plate is partially withdrawn to maintain downstream pressure on such increase and vice versa.

A one-way valve to control the release of pressurized gas from within a sealed container through a venting aperture. The valve comprises a layer of flexible material having an upper and a lower surface with a portion of the upper surface adhered to a surface of the container and overlaying the venting aperture. A channel is defined by a portion of the container and an adjacent portion of the flexible material which has not been adhered to the container. The channel is in communication with the venting aperture and an exhaust gas aperture in the layer of flexible material. The channel is operable between a closed and an open configuration upon gas pressure within the container exceeding a predetermined limit. When open the channel permits gas to flow from said container into the exterior atmosphere. When closed the channel restricts the flow of gas between the venting aperture and exhaust gas aperture.

A backflow prevention device with reduced pressure zone to be installed in water systems is provided and comprises a body provided with inlet, outlet and exhaust openings, a check assembly with a stem, an elastic element, and a plate, a mobile diaphragm or membrane adapted to interrupt the fluid connection between the outlet opening and inlet opening and between said inlet opening and exhaust opening, wherein said stem of said check assembly is stabilized with respect to said body, and said plate is slidably disposed along the stem and is cooperatively placed with the mobile diaphragm or membrane in order to interrupt the fluid connection between said inlet opening and said outlet opening.

A check valve (1) for a through hole in a compartment wall (100) comprises an elastic membrane (20) covering an open end (16) of a flow passage (14), a base (11) to which the elastic membrane (20) is fixed, and a protector (30) covering at least a portion of the elastic membrane (20), wherein the elastic membrane is fixed to the base in a state where it is elastically stretched over and forced against a sealing surface (17) surrounding the open end (16) so as to seal the flow passage (14). The elastic membrane lifts from the sealing surface when the pressure in the flow passage is high. The elastic membrane may be air- or gas-permeable and, preferably, waterproof so as to impart a low pressure venting functionality to the check valve.

A relief valve provides pressure relief when a fluid line exceeds a predetermined pressure. The valve includes a body which defines a cavity between inlet and outlet flowpaths. The valve includes a lever arm, which pivots around a pivot point as the valve changes between open and closed positions. A plunger assembly is disposed in the cavity and seals the cavity from the inlet and outlet flowpaths in the closed position. Fluid pressure from the inlet flow path causes the plunger assembly to contact the lever arm to urge the lever arm to rotate. The lever arm engages a spring at a further distance from the pivot point than the plunger assembly, the spring resisting pivoting of the lever arm and urging the valve to remain in the closed position unless a predetermined pressure is exceeded.

Valve device based on a closing disc formed by disc parts which are movably arranged on activation bolts extending between two stop discs, and where movement of the activation bolts or disc parts in longitudinal direction of the valve device results in that the relative position between the disc parts are changed and the valve device opens or closes.